Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

68 files changed, 13628 insertions, 0 deletions

diff --git a/netwerk/test/httpserver/README b/netwerk/test/httpserver/README
new file mode 100644
index 0000000000..97624789ca
--- /dev/null
+++ b/netwerk/test/httpserver/README
@@ -0,0 +1,101 @@
+httpd.js README
+===============
+
+httpd.js is a small cross-platform implementation of an HTTP/1.1 server in
+JavaScript for the Mozilla platform.
+
+httpd.js may be used as an XPCOM component, as an inline script in a document
+with XPCOM privileges, or from the XPCOM shell (xpcshell).  Currently, its most-
+supported method of use is from the XPCOM shell, where you can get all the
+dynamicity of JS in adding request handlers and the like, but component-based
+equivalent functionality is planned.
+
+
+Using httpd.js as an XPCOM Component
+------------------------------------
+
+First, create an XPT file for nsIHttpServer.idl, using the xpidl tool included
+in the Mozilla SDK for the environment in which you wish to run httpd.js.  See
+<http://developer.mozilla.org/en/docs/XPIDL:xpidl> for further details on how to
+do this.
+
+Next, register httpd.js and nsIHttpServer.xpt in your Mozilla application.  In
+Firefox, these simply need to be added to the /components directory of your XPI.
+Other applications may require use of regxpcom or other techniques; consult the
+applicable documentation for further details.
+
+Finally, load httpd.js into the current file, and create an instance of the
+server using the following command:
+
+  var server = new nsHttpServer();
+
+At this point you'll want to initialize the server, since by default it doesn't
+serve many useful paths.  For more information on this, see the IDL docs for the
+nsIHttpServer interface in nsIHttpServer.idl, particularly for
+registerDirectory (useful for mapping the contents of directories onto request
+paths), registerPathHandler (for setting a custom handler for a specific path on
+the server, such as CGI functionality), and registerFile (for mapping a file to
+a specific path).
+
+Finally, you'll want to start (and later stop) the server.  Here's some example
+code which does this:
+
+  server.start(8080);  // port on which server will operate
+
+  // ...server now runs and serves requests...
+
+  server.stop();
+
+This server will only respond to requests on 127.0.0.1:8080 or localhost:8080.
+If you want it to respond to requests at different hosts (say via a proxy
+mechanism), you must use server.identity.add() or server.identity.setPrimary()
+to add it.
+
+
+Using httpd.js as an Inline Script or from xpcshell
+---------------------------------------------------
+
+Using httpd.js as a script or from xpcshell isn't very different from using it
+as a component; the only real difference lies in how you create an instance of
+the server.  To create an instance, do the following:
+
+  var server = new nsHttpServer();
+
+You now can use |server| exactly as you would when |server| was created as an
+XPCOM component.  Note, however, that doing so will trample over the global
+namespace, and global values defined in httpd.js will leak into your script.
+This may typically be benign, but since some of the global values defined are
+constants (specifically, Cc/Ci/Cr as abbreviations for the classes, interfaces,
+and results properties of Components), it's possible this trampling could
+break your script.  In general you should use httpd.js as an XPCOM component
+whenever possible.
+
+
+Known Issues
+------------
+
+httpd.js makes no effort to time out requests, beyond any the socket itself
+might or might not provide.  I don't believe it provides any by default, but
+I haven't verified this.
+
+Every incoming request is processed by the corresponding request handler
+synchronously.  In other words, once the first CRLFCRLF of a request is
+received, the entire response is created before any new incoming requests can be
+served.  I anticipate adding asynchronous handler functionality in bug 396226,
+but it may be some time before that happens.
+
+There is no way to access the body of an incoming request.  This problem is
+merely a symptom of the previous one, and they will probably both be addressed
+at the same time.
+
+
+Other Goodies
+-------------
+
+A special testing function, |server|, is provided for use in xpcshell for quick
+testing of the server; see the source code for details on its use.  You don't
+want to use this in a script, however, because doing so will block until the
+server is shut down.  It's also a good example of how to use the basic
+functionality of httpd.js, if you need one.
+
+Have fun!
diff --git a/netwerk/test/httpserver/TODO b/netwerk/test/httpserver/TODO
new file mode 100644
index 0000000000..3a95466117
--- /dev/null
+++ b/netwerk/test/httpserver/TODO
@@ -0,0 +1,17 @@
+Bugs to fix:
+- make content-length generation not rely on .available() returning the entire
+  size of the body stream's contents -- some sort of wrapper (but how does that
+  work for the unscriptable method WriteSegments, which is good to support from
+  a performance standpoint?)
+
+Ideas for future improvements:
+- add API to disable response buffering which, when called, causes errors when
+  you try to do anything other than write to the body stream (i.e., modify
+  headers or status line) once you've written anything to it -- useful when
+  storing the entire response in memory is unfeasible (e.g., you're testing
+  >4GB download characteristics)
+- add an API which performs asynchronous response processing (instead of
+  nsIHttpRequestHandler.handle, which must construct the response before control
+  returns; |void asyncHandle(request, response)|) -- useful, and can it be done
+  in JS?
+- other awesomeness?
diff --git a/netwerk/test/httpserver/httpd.sys.mjs b/netwerk/test/httpserver/httpd.sys.mjs
new file mode 100644
index 0000000000..569e4d1489
--- /dev/null
+++ b/netwerk/test/httpserver/httpd.sys.mjs
@@ -0,0 +1,5576 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * An implementation of an HTTP server both as a loadable script and as an XPCOM
+ * component.  See the accompanying README file for user documentation on
+ * httpd.js.
+ */
+
+const CC = Components.Constructor;
+
+const PR_UINT32_MAX = Math.pow(2, 32) - 1;
+
+/** True if debugging output is enabled, false otherwise. */
+var DEBUG = false; // non-const *only* so tweakable in server tests
+
+/** True if debugging output should be timestamped. */
+var DEBUG_TIMESTAMP = false; // non-const so tweakable in server tests
+
+/**
+ * Sets the debugging status, intended for tweaking in server tests.
+ *
+ * @param {boolean} debug
+ *   Enables debugging output
+ * @param {boolean} debugTimestamp
+ *   Enables timestamping of the debugging output.
+ */
+export function setDebuggingStatus(debug, debugTimestamp) {
+  DEBUG = debug;
+  DEBUG_TIMESTAMP = debugTimestamp;
+}
+
+import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
+
+/**
+ * Asserts that the given condition holds.  If it doesn't, the given message is
+ * dumped, a stack trace is printed, and an exception is thrown to attempt to
+ * stop execution (which unfortunately must rely upon the exception not being
+ * accidentally swallowed by the code that uses it).
+ */
+function NS_ASSERT(cond, msg) {
+  if (DEBUG && !cond) {
+    dumpn("###!!!");
+    dumpn("###!!! ASSERTION" + (msg ? ": " + msg : "!"));
+    dumpn("###!!! Stack follows:");
+
+    var stack = new Error().stack.split(/\n/);
+    dumpn(
+      stack
+        .map(function (val) {
+          return "###!!!   " + val;
+        })
+        .join("\n")
+    );
+
+    throw Components.Exception("", Cr.NS_ERROR_ABORT);
+  }
+}
+
+/** Constructs an HTTP error object. */
+export function HttpError(code, description) {
+  this.code = code;
+  this.description = description;
+}
+
+HttpError.prototype = {
+  toString() {
+    return this.code + " " + this.description;
+  },
+};
+
+/**
+ * Errors thrown to trigger specific HTTP server responses.
+ */
+export var HTTP_400 = new HttpError(400, "Bad Request");
+
+export var HTTP_401 = new HttpError(401, "Unauthorized");
+export var HTTP_402 = new HttpError(402, "Payment Required");
+export var HTTP_403 = new HttpError(403, "Forbidden");
+export var HTTP_404 = new HttpError(404, "Not Found");
+export var HTTP_405 = new HttpError(405, "Method Not Allowed");
+export var HTTP_406 = new HttpError(406, "Not Acceptable");
+export var HTTP_407 = new HttpError(407, "Proxy Authentication Required");
+export var HTTP_408 = new HttpError(408, "Request Timeout");
+export var HTTP_409 = new HttpError(409, "Conflict");
+export var HTTP_410 = new HttpError(410, "Gone");
+export var HTTP_411 = new HttpError(411, "Length Required");
+export var HTTP_412 = new HttpError(412, "Precondition Failed");
+export var HTTP_413 = new HttpError(413, "Request Entity Too Large");
+export var HTTP_414 = new HttpError(414, "Request-URI Too Long");
+export var HTTP_415 = new HttpError(415, "Unsupported Media Type");
+export var HTTP_417 = new HttpError(417, "Expectation Failed");
+export var HTTP_500 = new HttpError(500, "Internal Server Error");
+export var HTTP_501 = new HttpError(501, "Not Implemented");
+export var HTTP_502 = new HttpError(502, "Bad Gateway");
+export var HTTP_503 = new HttpError(503, "Service Unavailable");
+export var HTTP_504 = new HttpError(504, "Gateway Timeout");
+export var HTTP_505 = new HttpError(505, "HTTP Version Not Supported");
+
+/** Creates a hash with fields corresponding to the values in arr. */
+function array2obj(arr) {
+  var obj = {};
+  for (var i = 0; i < arr.length; i++) {
+    obj[arr[i]] = arr[i];
+  }
+  return obj;
+}
+
+/** Returns an array of the integers x through y, inclusive. */
+function range(x, y) {
+  var arr = [];
+  for (var i = x; i <= y; i++) {
+    arr.push(i);
+  }
+  return arr;
+}
+
+/** An object (hash) whose fields are the numbers of all HTTP error codes. */
+const HTTP_ERROR_CODES = array2obj(range(400, 417).concat(range(500, 505)));
+
+/**
+ * The character used to distinguish hidden files from non-hidden files, a la
+ * the leading dot in Apache.  Since that mechanism also hides files from
+ * easy display in LXR, ls output, etc. however, we choose instead to use a
+ * suffix character.  If a requested file ends with it, we append another
+ * when getting the file on the server.  If it doesn't, we just look up that
+ * file.  Therefore, any file whose name ends with exactly one of the character
+ * is "hidden" and available for use by the server.
+ */
+const HIDDEN_CHAR = "^";
+
+/**
+ * The file name suffix indicating the file containing overridden headers for
+ * a requested file.
+ */
+const HEADERS_SUFFIX = HIDDEN_CHAR + "headers" + HIDDEN_CHAR;
+const INFORMATIONAL_RESPONSE_SUFFIX =
+  HIDDEN_CHAR + "informationalResponse" + HIDDEN_CHAR;
+
+/** Type used to denote SJS scripts for CGI-like functionality. */
+const SJS_TYPE = "sjs";
+
+/** Base for relative timestamps produced by dumpn(). */
+var firstStamp = 0;
+
+/** dump(str) with a trailing "\n" -- only outputs if DEBUG. */
+export function dumpn(str) {
+  if (DEBUG) {
+    var prefix = "HTTPD-INFO | ";
+    if (DEBUG_TIMESTAMP) {
+      if (firstStamp === 0) {
+        firstStamp = Date.now();
+      }
+
+      var elapsed = Date.now() - firstStamp; // milliseconds
+      var min = Math.floor(elapsed / 60000);
+      var sec = (elapsed % 60000) / 1000;
+
+      if (sec < 10) {
+        prefix += min + ":0" + sec.toFixed(3) + " | ";
+      } else {
+        prefix += min + ":" + sec.toFixed(3) + " | ";
+      }
+    }
+
+    dump(prefix + str + "\n");
+  }
+}
+
+/** Dumps the current JS stack if DEBUG. */
+function dumpStack() {
+  // peel off the frames for dumpStack() and Error()
+  var stack = new Error().stack.split(/\n/).slice(2);
+  stack.forEach(dumpn);
+}
+
+/**
+ * JavaScript constructors for commonly-used classes; precreating these is a
+ * speedup over doing the same from base principles.  See the docs at
+ * http://developer.mozilla.org/en/docs/Components.Constructor for details.
+ */
+const ServerSocket = CC(
+  "@mozilla.org/network/server-socket;1",
+  "nsIServerSocket",
+  "init"
+);
+const ServerSocketIPv6 = CC(
+  "@mozilla.org/network/server-socket;1",
+  "nsIServerSocket",
+  "initIPv6"
+);
+const ServerSocketDualStack = CC(
+  "@mozilla.org/network/server-socket;1",
+  "nsIServerSocket",
+  "initDualStack"
+);
+const ScriptableInputStream = CC(
+  "@mozilla.org/scriptableinputstream;1",
+  "nsIScriptableInputStream",
+  "init"
+);
+const Pipe = CC("@mozilla.org/pipe;1", "nsIPipe", "init");
+const FileInputStream = CC(
+  "@mozilla.org/network/file-input-stream;1",
+  "nsIFileInputStream",
+  "init"
+);
+const ConverterInputStream = CC(
+  "@mozilla.org/intl/converter-input-stream;1",
+  "nsIConverterInputStream",
+  "init"
+);
+const WritablePropertyBag = CC(
+  "@mozilla.org/hash-property-bag;1",
+  "nsIWritablePropertyBag2"
+);
+const SupportsString = CC(
+  "@mozilla.org/supports-string;1",
+  "nsISupportsString"
+);
+
+/* These two are non-const only so a test can overwrite them. */
+var BinaryInputStream = CC(
+  "@mozilla.org/binaryinputstream;1",
+  "nsIBinaryInputStream",
+  "setInputStream"
+);
+var BinaryOutputStream = CC(
+  "@mozilla.org/binaryoutputstream;1",
+  "nsIBinaryOutputStream",
+  "setOutputStream"
+);
+
+export function overrideBinaryStreamsForTests(
+  inputStream,
+  outputStream,
+  responseSegmentSize
+) {
+  BinaryInputStream = inputStream;
+  BinaryOutputStream = outputStream;
+  Response.SEGMENT_SIZE = responseSegmentSize;
+}
+
+/**
+ * Returns the RFC 822/1123 representation of a date.
+ *
+ * @param date : Number
+ *   the date, in milliseconds from midnight (00:00:00), January 1, 1970 GMT
+ * @returns string
+ *   the representation of the given date
+ */
+function toDateString(date) {
+  //
+  // rfc1123-date = wkday "," SP date1 SP time SP "GMT"
+  // date1        = 2DIGIT SP month SP 4DIGIT
+  //                ; day month year (e.g., 02 Jun 1982)
+  // time         = 2DIGIT ":" 2DIGIT ":" 2DIGIT
+  //                ; 00:00:00 - 23:59:59
+  // wkday        = "Mon" | "Tue" | "Wed"
+  //              | "Thu" | "Fri" | "Sat" | "Sun"
+  // month        = "Jan" | "Feb" | "Mar" | "Apr"
+  //              | "May" | "Jun" | "Jul" | "Aug"
+  //              | "Sep" | "Oct" | "Nov" | "Dec"
+  //
+
+  const wkdayStrings = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"];
+  const monthStrings = [
+    "Jan",
+    "Feb",
+    "Mar",
+    "Apr",
+    "May",
+    "Jun",
+    "Jul",
+    "Aug",
+    "Sep",
+    "Oct",
+    "Nov",
+    "Dec",
+  ];
+
+  /**
+   * Processes a date and returns the encoded UTC time as a string according to
+   * the format specified in RFC 2616.
+   *
+   * @param date : Date
+   *   the date to process
+   * @returns string
+   *   a string of the form "HH:MM:SS", ranging from "00:00:00" to "23:59:59"
+   */
+  function toTime(date) {
+    var hrs = date.getUTCHours();
+    var rv = hrs < 10 ? "0" + hrs : hrs;
+
+    var mins = date.getUTCMinutes();
+    rv += ":";
+    rv += mins < 10 ? "0" + mins : mins;
+
+    var secs = date.getUTCSeconds();
+    rv += ":";
+    rv += secs < 10 ? "0" + secs : secs;
+
+    return rv;
+  }
+
+  /**
+   * Processes a date and returns the encoded UTC date as a string according to
+   * the date1 format specified in RFC 2616.
+   *
+   * @param date : Date
+   *   the date to process
+   * @returns string
+   *   a string of the form "HH:MM:SS", ranging from "00:00:00" to "23:59:59"
+   */
+  function toDate1(date) {
+    var day = date.getUTCDate();
+    var month = date.getUTCMonth();
+    var year = date.getUTCFullYear();
+
+    var rv = day < 10 ? "0" + day : day;
+    rv += " " + monthStrings[month];
+    rv += " " + year;
+
+    return rv;
+  }
+
+  date = new Date(date);
+
+  const fmtString = "%wkday%, %date1% %time% GMT";
+  var rv = fmtString.replace("%wkday%", wkdayStrings[date.getUTCDay()]);
+  rv = rv.replace("%time%", toTime(date));
+  return rv.replace("%date1%", toDate1(date));
+}
+
+/**
+ * Instantiates a new HTTP server.
+ */
+export function nsHttpServer() {
+  /** The port on which this server listens. */
+  this._port = undefined;
+
+  /** The socket associated with this. */
+  this._socket = null;
+
+  /** The handler used to process requests to this server. */
+  this._handler = new ServerHandler(this);
+
+  /** Naming information for this server. */
+  this._identity = new ServerIdentity();
+
+  /**
+   * Indicates when the server is to be shut down at the end of the request.
+   */
+  this._doQuit = false;
+
+  /**
+   * True if the socket in this is closed (and closure notifications have been
+   * sent and processed if the socket was ever opened), false otherwise.
+   */
+  this._socketClosed = true;
+
+  /**
+   * Used for tracking existing connections and ensuring that all connections
+   * are properly cleaned up before server shutdown; increases by 1 for every
+   * new incoming connection.
+   */
+  this._connectionGen = 0;
+
+  /**
+   * Hash of all open connections, indexed by connection number at time of
+   * creation.
+   */
+  this._connections = {};
+}
+
+nsHttpServer.prototype = {
+  // NSISERVERSOCKETLISTENER
+
+  /**
+   * Processes an incoming request coming in on the given socket and contained
+   * in the given transport.
+   *
+   * @param socket : nsIServerSocket
+   *   the socket through which the request was served
+   * @param trans : nsISocketTransport
+   *   the transport for the request/response
+   * @see nsIServerSocketListener.onSocketAccepted
+   */
+  onSocketAccepted(socket, trans) {
+    dumpn("*** onSocketAccepted(socket=" + socket + ", trans=" + trans + ")");
+
+    dumpn(">>> new connection on " + trans.host + ":" + trans.port);
+
+    const SEGMENT_SIZE = 8192;
+    const SEGMENT_COUNT = 1024;
+    try {
+      var input = trans
+        .openInputStream(0, SEGMENT_SIZE, SEGMENT_COUNT)
+        .QueryInterface(Ci.nsIAsyncInputStream);
+      var output = trans.openOutputStream(0, 0, 0);
+    } catch (e) {
+      dumpn("*** error opening transport streams: " + e);
+      trans.close(Cr.NS_BINDING_ABORTED);
+      return;
+    }
+
+    var connectionNumber = ++this._connectionGen;
+
+    try {
+      var conn = new Connection(
+        input,
+        output,
+        this,
+        socket.port,
+        trans.port,
+        connectionNumber,
+        trans
+      );
+      var reader = new RequestReader(conn);
+
+      // XXX add request timeout functionality here!
+
+      // Note: must use main thread here, or we might get a GC that will cause
+      //       threadsafety assertions.  We really need to fix XPConnect so that
+      //       you can actually do things in multi-threaded JS.  :-(
+      input.asyncWait(reader, 0, 0, Services.tm.mainThread);
+    } catch (e) {
+      // Assume this connection can't be salvaged and bail on it completely;
+      // don't attempt to close it so that we can assert that any connection
+      // being closed is in this._connections.
+      dumpn("*** error in initial request-processing stages: " + e);
+      trans.close(Cr.NS_BINDING_ABORTED);
+      return;
+    }
+
+    this._connections[connectionNumber] = conn;
+    dumpn("*** starting connection " + connectionNumber);
+  },
+
+  /**
+   * Called when the socket associated with this is closed.
+   *
+   * @param socket : nsIServerSocket
+   *   the socket being closed
+   * @param status : nsresult
+   *   the reason the socket stopped listening (NS_BINDING_ABORTED if the server
+   *   was stopped using nsIHttpServer.stop)
+   * @see nsIServerSocketListener.onStopListening
+   */
+  onStopListening(socket, status) {
+    dumpn(">>> shutting down server on port " + socket.port);
+    for (var n in this._connections) {
+      if (!this._connections[n]._requestStarted) {
+        this._connections[n].close();
+      }
+    }
+    this._socketClosed = true;
+    if (this._hasOpenConnections()) {
+      dumpn("*** open connections!!!");
+    }
+    if (!this._hasOpenConnections()) {
+      dumpn("*** no open connections, notifying async from onStopListening");
+
+      // Notify asynchronously so that any pending teardown in stop() has a
+      // chance to run first.
+      var self = this;
+      var stopEvent = {
+        run() {
+          dumpn("*** _notifyStopped async callback");
+          self._notifyStopped();
+        },
+      };
+      Services.tm.currentThread.dispatch(
+        stopEvent,
+        Ci.nsIThread.DISPATCH_NORMAL
+      );
+    }
+  },
+
+  // NSIHTTPSERVER
+
+  //
+  // see nsIHttpServer.start
+  //
+  start(port) {
+    this._start(port, "localhost");
+  },
+
+  //
+  // see nsIHttpServer.start_ipv6
+  //
+  start_ipv6(port) {
+    this._start(port, "[::1]");
+  },
+
+  start_dualStack(port) {
+    this._start(port, "[::1]", true);
+  },
+
+  _start(port, host, dualStack) {
+    if (this._socket) {
+      throw Components.Exception("", Cr.NS_ERROR_ALREADY_INITIALIZED);
+    }
+
+    this._port = port;
+    this._doQuit = this._socketClosed = false;
+
+    this._host = host;
+
+    // The listen queue needs to be long enough to handle
+    // network.http.max-persistent-connections-per-server or
+    // network.http.max-persistent-connections-per-proxy concurrent
+    // connections, plus a safety margin in case some other process is
+    // talking to the server as well.
+    var maxConnections =
+      5 +
+      Math.max(
+        Services.prefs.getIntPref(
+          "network.http.max-persistent-connections-per-server"
+        ),
+        Services.prefs.getIntPref(
+          "network.http.max-persistent-connections-per-proxy"
+        )
+      );
+
+    try {
+      var loopback = true;
+      if (
+        this._host != "127.0.0.1" &&
+        this._host != "localhost" &&
+        this._host != "[::1]"
+      ) {
+        loopback = false;
+      }
+
+      // When automatically selecting a port, sometimes the chosen port is
+      // "blocked" from clients. We don't want to use these ports because
+      // tests will intermittently fail. So, we simply keep trying to to
+      // get a server socket until a valid port is obtained. We limit
+      // ourselves to finite attempts just so we don't loop forever.
+      var socket;
+      for (var i = 100; i; i--) {
+        var temp = null;
+        if (dualStack) {
+          temp = new ServerSocketDualStack(this._port, maxConnections);
+        } else if (this._host.includes(":")) {
+          temp = new ServerSocketIPv6(
+            this._port,
+            loopback, // true = localhost, false = everybody
+            maxConnections
+          );
+        } else {
+          temp = new ServerSocket(
+            this._port,
+            loopback, // true = localhost, false = everybody
+            maxConnections
+          );
+        }
+
+        var allowed = Services.io.allowPort(temp.port, "http");
+        if (!allowed) {
+          dumpn(
+            ">>>Warning: obtained ServerSocket listens on a blocked " +
+              "port: " +
+              temp.port
+          );
+        }
+
+        if (!allowed && this._port == -1) {
+          dumpn(">>>Throwing away ServerSocket with bad port.");
+          temp.close();
+          continue;
+        }
+
+        socket = temp;
+        break;
+      }
+
+      if (!socket) {
+        throw new Error(
+          "No socket server available. Are there no available ports?"
+        );
+      }
+
+      socket.asyncListen(this);
+      this._port = socket.port;
+      this._identity._initialize(socket.port, host, true, dualStack);
+      this._socket = socket;
+      dumpn(
+        ">>> listening on port " +
+          socket.port +
+          ", " +
+          maxConnections +
+          " pending connections"
+      );
+    } catch (e) {
+      dump("\n!!! could not start server on port " + port + ": " + e + "\n\n");
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+  },
+
+  //
+  // see nsIHttpServer.stop
+  //
+  stop(callback) {
+    if (!this._socket) {
+      throw Components.Exception("", Cr.NS_ERROR_UNEXPECTED);
+    }
+
+    // If no argument was provided to stop, return a promise.
+    let returnValue = undefined;
+    if (!callback) {
+      returnValue = new Promise(resolve => {
+        callback = resolve;
+      });
+    }
+
+    this._stopCallback =
+      typeof callback === "function"
+        ? callback
+        : function () {
+            callback.onStopped();
+          };
+
+    dumpn(">>> stopping listening on port " + this._socket.port);
+    this._socket.close();
+    this._socket = null;
+
+    // We can't have this identity any more, and the port on which we're running
+    // this server now could be meaningless the next time around.
+    this._identity._teardown();
+
+    this._doQuit = false;
+
+    // socket-close notification and pending request completion happen async
+
+    return returnValue;
+  },
+
+  //
+  // see nsIHttpServer.registerFile
+  //
+  registerFile(path, file, handler) {
+    if (file && (!file.exists() || file.isDirectory())) {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    this._handler.registerFile(path, file, handler);
+  },
+
+  //
+  // see nsIHttpServer.registerDirectory
+  //
+  registerDirectory(path, directory) {
+    // XXX true path validation!
+    if (
+      path.charAt(0) != "/" ||
+      path.charAt(path.length - 1) != "/" ||
+      (directory && (!directory.exists() || !directory.isDirectory()))
+    ) {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    // XXX determine behavior of nonexistent /foo/bar when a /foo/bar/ mapping
+    //     exists!
+
+    this._handler.registerDirectory(path, directory);
+  },
+
+  //
+  // see nsIHttpServer.registerPathHandler
+  //
+  registerPathHandler(path, handler) {
+    this._handler.registerPathHandler(path, handler);
+  },
+
+  //
+  // see nsIHttpServer.registerPrefixHandler
+  //
+  registerPrefixHandler(prefix, handler) {
+    this._handler.registerPrefixHandler(prefix, handler);
+  },
+
+  //
+  // see nsIHttpServer.registerErrorHandler
+  //
+  registerErrorHandler(code, handler) {
+    this._handler.registerErrorHandler(code, handler);
+  },
+
+  //
+  // see nsIHttpServer.setIndexHandler
+  //
+  setIndexHandler(handler) {
+    this._handler.setIndexHandler(handler);
+  },
+
+  //
+  // see nsIHttpServer.registerContentType
+  //
+  registerContentType(ext, type) {
+    this._handler.registerContentType(ext, type);
+  },
+
+  get connectionNumber() {
+    return this._connectionGen;
+  },
+
+  //
+  // see nsIHttpServer.serverIdentity
+  //
+  get identity() {
+    return this._identity;
+  },
+
+  //
+  // see nsIHttpServer.getState
+  //
+  getState(path, k) {
+    return this._handler._getState(path, k);
+  },
+
+  //
+  // see nsIHttpServer.setState
+  //
+  setState(path, k, v) {
+    return this._handler._setState(path, k, v);
+  },
+
+  //
+  // see nsIHttpServer.getSharedState
+  //
+  getSharedState(k) {
+    return this._handler._getSharedState(k);
+  },
+
+  //
+  // see nsIHttpServer.setSharedState
+  //
+  setSharedState(k, v) {
+    return this._handler._setSharedState(k, v);
+  },
+
+  //
+  // see nsIHttpServer.getObjectState
+  //
+  getObjectState(k) {
+    return this._handler._getObjectState(k);
+  },
+
+  //
+  // see nsIHttpServer.setObjectState
+  //
+  setObjectState(k, v) {
+    return this._handler._setObjectState(k, v);
+  },
+
+  get wrappedJSObject() {
+    return this;
+  },
+
+  // NSISUPPORTS
+
+  //
+  // see nsISupports.QueryInterface
+  //
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIHttpServer",
+    "nsIServerSocketListener",
+  ]),
+
+  // NON-XPCOM PUBLIC API
+
+  /**
+   * Returns true iff this server is not running (and is not in the process of
+   * serving any requests still to be processed when the server was last
+   * stopped after being run).
+   */
+  isStopped() {
+    return this._socketClosed && !this._hasOpenConnections();
+  },
+
+  // PRIVATE IMPLEMENTATION
+
+  /** True if this server has any open connections to it, false otherwise. */
+  _hasOpenConnections() {
+    //
+    // If we have any open connections, they're tracked as numeric properties on
+    // |this._connections|.  The non-standard __count__ property could be used
+    // to check whether there are any properties, but standard-wise, even
+    // looking forward to ES5, there's no less ugly yet still O(1) way to do
+    // this.
+    //
+    for (var n in this._connections) {
+      return true;
+    }
+    return false;
+  },
+
+  /** Calls the server-stopped callback provided when stop() was called. */
+  _notifyStopped() {
+    NS_ASSERT(this._stopCallback !== null, "double-notifying?");
+    NS_ASSERT(!this._hasOpenConnections(), "should be done serving by now");
+
+    //
+    // NB: We have to grab this now, null out the member, *then* call the
+    //     callback here, or otherwise the callback could (indirectly) futz with
+    //     this._stopCallback by starting and immediately stopping this, at
+    //     which point we'd be nulling out a field we no longer have a right to
+    //     modify.
+    //
+    var callback = this._stopCallback;
+    this._stopCallback = null;
+    try {
+      callback();
+    } catch (e) {
+      // not throwing because this is specified as being usually (but not
+      // always) asynchronous
+      dump("!!! error running onStopped callback: " + e + "\n");
+    }
+  },
+
+  /**
+   * Notifies this server that the given connection has been closed.
+   *
+   * @param connection : Connection
+   *   the connection that was closed
+   */
+  _connectionClosed(connection) {
+    NS_ASSERT(
+      connection.number in this._connections,
+      "closing a connection " +
+        this +
+        " that we never added to the " +
+        "set of open connections?"
+    );
+    NS_ASSERT(
+      this._connections[connection.number] === connection,
+      "connection number mismatch?  " + this._connections[connection.number]
+    );
+    delete this._connections[connection.number];
+
+    // Fire a pending server-stopped notification if it's our responsibility.
+    if (!this._hasOpenConnections() && this._socketClosed) {
+      this._notifyStopped();
+    }
+  },
+
+  /**
+   * Requests that the server be shut down when possible.
+   */
+  _requestQuit() {
+    dumpn(">>> requesting a quit");
+    dumpStack();
+    this._doQuit = true;
+  },
+};
+
+export var HttpServer = nsHttpServer;
+
+export class NodeServer {
+  // Executes command in the context of a node server.
+  // See handler in moz-http2.js
+  //
+  // Example use:
+  // let id = NodeServer.fork(); // id is a random string
+  // await NodeServer.execute(id, `"hello"`)
+  // > "hello"
+  // await NodeServer.execute(id, `(() => "hello")()`)
+  // > "hello"
+  // await NodeServer.execute(id, `(() => var_defined_on_server)()`)
+  // > "0"
+  // await NodeServer.execute(id, `var_defined_on_server`)
+  // > "0"
+  // function f(param) { if (param) return param; return "bla"; }
+  // await NodeServer.execute(id, f); // Defines the function on the server
+  // await NodeServer.execute(id, `f()`) // executes defined function
+  // > "bla"
+  // let result = await NodeServer.execute(id, `f("test")`);
+  // > "test"
+  // await NodeServer.kill(id); // shuts down the server
+
+  // Forks a new node server using moz-http2-child.js as a starting point
+  static fork() {
+    return this.sendCommand("", "/fork");
+  }
+  // Executes command in the context of the node server indicated by `id`
+  static execute(id, command) {
+    return this.sendCommand(command, `/execute/${id}`);
+  }
+  // Shuts down the server
+  static kill(id) {
+    return this.sendCommand("", `/kill/${id}`);
+  }
+
+  // Issues a request to the node server (handler defined in moz-http2.js)
+  // This method should not be called directly.
+  static sendCommand(command, path) {
+    let h2Port = Services.env.get("MOZNODE_EXEC_PORT");
+    if (!h2Port) {
+      throw new Error("Could not find MOZNODE_EXEC_PORT");
+    }
+
+    let req = new XMLHttpRequest();
+    const serverIP =
+      AppConstants.platform == "android" ? "10.0.2.2" : "127.0.0.1";
+    req.open("POST", `http://${serverIP}:${h2Port}${path}`);
+    req.channel.QueryInterface(Ci.nsIHttpChannelInternal).bypassProxy = true;
+
+    // Passing a function to NodeServer.execute will define that function
+    // in node. It can be called in a later execute command.
+    let isFunction = function (obj) {
+      return !!(obj && obj.constructor && obj.call && obj.apply);
+    };
+    let payload = command;
+    if (isFunction(command)) {
+      payload = `${command.name} = ${command.toString()};`;
+    }
+
+    return new Promise((resolve, reject) => {
+      req.onload = () => {
+        let x = null;
+
+        if (req.statusText != "OK") {
+          reject(`XHR request failed: ${req.statusText}`);
+          return;
+        }
+
+        try {
+          x = JSON.parse(req.responseText);
+        } catch (e) {
+          reject(`Failed to parse ${req.responseText} - ${e}`);
+          return;
+        }
+
+        if (x.error) {
+          let e = new Error(x.error, "", 0);
+          e.stack = x.errorStack;
+          reject(e);
+          return;
+        }
+        resolve(x.result);
+      };
+      req.onerror = e => {
+        reject(e);
+      };
+
+      req.send(payload.toString());
+    });
+  }
+}
+
+//
+// RFC 2396 section 3.2.2:
+//
+// host        = hostname | IPv4address
+// hostname    = *( domainlabel "." ) toplabel [ "." ]
+// domainlabel = alphanum | alphanum *( alphanum | "-" ) alphanum
+// toplabel    = alpha | alpha *( alphanum | "-" ) alphanum
+// IPv4address = 1*digit "." 1*digit "." 1*digit "." 1*digit
+//
+// IPv6 addresses are notably lacking in the above definition of 'host'.
+// RFC 2732 section 3 extends the host definition:
+// host          = hostname | IPv4address | IPv6reference
+// ipv6reference = "[" IPv6address "]"
+//
+// RFC 3986 supersedes RFC 2732 and offers a more precise definition of a IPv6
+// address. For simplicity, the regexp below captures all canonical IPv6
+// addresses (e.g. [::1]), but may also match valid non-canonical IPv6 addresses
+// (e.g. [::127.0.0.1]) and even invalid bracketed addresses ([::], [99999::]).
+
+const HOST_REGEX = new RegExp(
+  "^(?:" +
+    // *( domainlabel "." )
+    "(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)*" +
+    // toplabel [ "." ]
+    "[a-z](?:[a-z0-9-]*[a-z0-9])?\\.?" +
+    "|" +
+    // IPv4 address
+    "\\d+\\.\\d+\\.\\d+\\.\\d+" +
+    "|" +
+    // IPv6 addresses (e.g. [::1])
+    "\\[[:0-9a-f]+\\]" +
+    ")$",
+  "i"
+);
+
+/**
+ * Represents the identity of a server.  An identity consists of a set of
+ * (scheme, host, port) tuples denoted as locations (allowing a single server to
+ * serve multiple sites or to be used behind both HTTP and HTTPS proxies for any
+ * host/port).  Any incoming request must be to one of these locations, or it
+ * will be rejected with an HTTP 400 error.  One location, denoted as the
+ * primary location, is the location assigned in contexts where a location
+ * cannot otherwise be endogenously derived, such as for HTTP/1.0 requests.
+ *
+ * A single identity may contain at most one location per unique host/port pair;
+ * other than that, no restrictions are placed upon what locations may
+ * constitute an identity.
+ */
+function ServerIdentity() {
+  /** The scheme of the primary location. */
+  this._primaryScheme = "http";
+
+  /** The hostname of the primary location. */
+  this._primaryHost = "127.0.0.1";
+
+  /** The port number of the primary location. */
+  this._primaryPort = -1;
+
+  /**
+   * The current port number for the corresponding server, stored so that a new
+   * primary location can always be set if the current one is removed.
+   */
+  this._defaultPort = -1;
+
+  /**
+   * Maps hosts to maps of ports to schemes, e.g. the following would represent
+   * https://example.com:789/ and http://example.org/:
+   *
+   *   {
+   *     "xexample.com": { 789: "https" },
+   *     "xexample.org": { 80: "http" }
+   *   }
+   *
+   * Note the "x" prefix on hostnames, which prevents collisions with special
+   * JS names like "prototype".
+   */
+  this._locations = { xlocalhost: {} };
+}
+ServerIdentity.prototype = {
+  // NSIHTTPSERVERIDENTITY
+
+  //
+  // see nsIHttpServerIdentity.primaryScheme
+  //
+  get primaryScheme() {
+    if (this._primaryPort === -1) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_INITIALIZED);
+    }
+    return this._primaryScheme;
+  },
+
+  //
+  // see nsIHttpServerIdentity.primaryHost
+  //
+  get primaryHost() {
+    if (this._primaryPort === -1) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_INITIALIZED);
+    }
+    return this._primaryHost;
+  },
+
+  //
+  // see nsIHttpServerIdentity.primaryPort
+  //
+  get primaryPort() {
+    if (this._primaryPort === -1) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_INITIALIZED);
+    }
+    return this._primaryPort;
+  },
+
+  //
+  // see nsIHttpServerIdentity.add
+  //
+  add(scheme, host, port) {
+    this._validate(scheme, host, port);
+
+    var entry = this._locations["x" + host];
+    if (!entry) {
+      this._locations["x" + host] = entry = {};
+    }
+
+    entry[port] = scheme;
+  },
+
+  //
+  // see nsIHttpServerIdentity.remove
+  //
+  remove(scheme, host, port) {
+    this._validate(scheme, host, port);
+
+    var entry = this._locations["x" + host];
+    if (!entry) {
+      return false;
+    }
+
+    var present = port in entry;
+    delete entry[port];
+
+    if (
+      this._primaryScheme == scheme &&
+      this._primaryHost == host &&
+      this._primaryPort == port &&
+      this._defaultPort !== -1
+    ) {
+      // Always keep at least one identity in existence at any time, unless
+      // we're in the process of shutting down (the last condition above).
+      this._primaryPort = -1;
+      this._initialize(this._defaultPort, host, false);
+    }
+
+    return present;
+  },
+
+  //
+  // see nsIHttpServerIdentity.has
+  //
+  has(scheme, host, port) {
+    this._validate(scheme, host, port);
+
+    return (
+      "x" + host in this._locations &&
+      scheme === this._locations["x" + host][port]
+    );
+  },
+
+  //
+  // see nsIHttpServerIdentity.has
+  //
+  getScheme(host, port) {
+    this._validate("http", host, port);
+
+    var entry = this._locations["x" + host];
+    if (!entry) {
+      return "";
+    }
+
+    return entry[port] || "";
+  },
+
+  //
+  // see nsIHttpServerIdentity.setPrimary
+  //
+  setPrimary(scheme, host, port) {
+    this._validate(scheme, host, port);
+
+    this.add(scheme, host, port);
+
+    this._primaryScheme = scheme;
+    this._primaryHost = host;
+    this._primaryPort = port;
+  },
+
+  // NSISUPPORTS
+
+  //
+  // see nsISupports.QueryInterface
+  //
+  QueryInterface: ChromeUtils.generateQI(["nsIHttpServerIdentity"]),
+
+  // PRIVATE IMPLEMENTATION
+
+  /**
+   * Initializes the primary name for the corresponding server, based on the
+   * provided port number.
+   */
+  _initialize(port, host, addSecondaryDefault, dualStack) {
+    this._host = host;
+    if (this._primaryPort !== -1) {
+      this.add("http", host, port);
+    } else {
+      this.setPrimary("http", "localhost", port);
+    }
+    this._defaultPort = port;
+
+    // Only add this if we're being called at server startup
+    if (addSecondaryDefault && host != "127.0.0.1") {
+      if (host.includes(":")) {
+        this.add("http", "[::1]", port);
+        if (dualStack) {
+          this.add("http", "127.0.0.1", port);
+        }
+      } else {
+        this.add("http", "127.0.0.1", port);
+      }
+    }
+  },
+
+  /**
+   * Called at server shutdown time, unsets the primary location only if it was
+   * the default-assigned location and removes the default location from the
+   * set of locations used.
+   */
+  _teardown() {
+    if (this._host != "127.0.0.1") {
+      // Not the default primary location, nothing special to do here
+      this.remove("http", "127.0.0.1", this._defaultPort);
+    }
+
+    // This is a *very* tricky bit of reasoning here; make absolutely sure the
+    // tests for this code pass before you commit changes to it.
+    if (
+      this._primaryScheme == "http" &&
+      this._primaryHost == this._host &&
+      this._primaryPort == this._defaultPort
+    ) {
+      // Make sure we don't trigger the readding logic in .remove(), then remove
+      // the default location.
+      var port = this._defaultPort;
+      this._defaultPort = -1;
+      this.remove("http", this._host, port);
+
+      // Ensure a server start triggers the setPrimary() path in ._initialize()
+      this._primaryPort = -1;
+    } else {
+      // No reason not to remove directly as it's not our primary location
+      this.remove("http", this._host, this._defaultPort);
+    }
+  },
+
+  /**
+   * Ensures scheme, host, and port are all valid with respect to RFC 2396.
+   *
+   * @throws NS_ERROR_ILLEGAL_VALUE
+   *   if any argument doesn't match the corresponding production
+   */
+  _validate(scheme, host, port) {
+    if (scheme !== "http" && scheme !== "https") {
+      dumpn("*** server only supports http/https schemes: '" + scheme + "'");
+      dumpStack();
+      throw Components.Exception("", Cr.NS_ERROR_ILLEGAL_VALUE);
+    }
+    if (!HOST_REGEX.test(host)) {
+      dumpn("*** unexpected host: '" + host + "'");
+      throw Components.Exception("", Cr.NS_ERROR_ILLEGAL_VALUE);
+    }
+    if (port < 0 || port > 65535) {
+      dumpn("*** unexpected port: '" + port + "'");
+      throw Components.Exception("", Cr.NS_ERROR_ILLEGAL_VALUE);
+    }
+  },
+};
+
+/**
+ * Represents a connection to the server (and possibly in the future the thread
+ * on which the connection is processed).
+ *
+ * @param input : nsIInputStream
+ *   stream from which incoming data on the connection is read
+ * @param output : nsIOutputStream
+ *   stream to write data out the connection
+ * @param server : nsHttpServer
+ *   the server handling the connection
+ * @param port : int
+ *   the port on which the server is running
+ * @param outgoingPort : int
+ *   the outgoing port used by this connection
+ * @param number : uint
+ *   a serial number used to uniquely identify this connection
+ */
+function Connection(
+  input,
+  output,
+  server,
+  port,
+  outgoingPort,
+  number,
+  transport
+) {
+  dumpn("*** opening new connection " + number + " on port " + outgoingPort);
+
+  /** Stream of incoming data. */
+  this.input = input;
+
+  /** Stream for outgoing data. */
+  this.output = output;
+
+  /** The server associated with this request. */
+  this.server = server;
+
+  /** The port on which the server is running. */
+  this.port = port;
+
+  /** The outgoing poort used by this connection. */
+  this._outgoingPort = outgoingPort;
+
+  /** The serial number of this connection. */
+  this.number = number;
+
+  /** Reference to the underlying transport. */
+  this.transport = transport;
+
+  /**
+   * The request for which a response is being generated, null if the
+   * incoming request has not been fully received or if it had errors.
+   */
+  this.request = null;
+
+  /** This allows a connection to disambiguate between a peer initiating a
+   *  close and the socket being forced closed on shutdown.
+   */
+  this._closed = false;
+
+  /** State variable for debugging. */
+  this._processed = false;
+
+  /** whether or not 1st line of request has been received */
+  this._requestStarted = false;
+}
+Connection.prototype = {
+  /** Closes this connection's input/output streams. */
+  close() {
+    if (this._closed) {
+      return;
+    }
+
+    dumpn(
+      "*** closing connection " + this.number + " on port " + this._outgoingPort
+    );
+
+    this.input.close();
+    this.output.close();
+    this._closed = true;
+
+    var server = this.server;
+    server._connectionClosed(this);
+
+    // If an error triggered a server shutdown, act on it now
+    if (server._doQuit) {
+      server.stop(function () {
+        /* not like we can do anything better */
+      });
+    }
+  },
+
+  /**
+   * Initiates processing of this connection, using the data in the given
+   * request.
+   *
+   * @param request : Request
+   *   the request which should be processed
+   */
+  process(request) {
+    NS_ASSERT(!this._closed && !this._processed);
+
+    this._processed = true;
+
+    this.request = request;
+    this.server._handler.handleResponse(this);
+  },
+
+  /**
+   * Initiates processing of this connection, generating a response with the
+   * given HTTP error code.
+   *
+   * @param code : uint
+   *   an HTTP code, so in the range [0, 1000)
+   * @param request : Request
+   *   incomplete data about the incoming request (since there were errors
+   *   during its processing
+   */
+  processError(code, request) {
+    NS_ASSERT(!this._closed && !this._processed);
+
+    this._processed = true;
+    this.request = request;
+    this.server._handler.handleError(code, this);
+  },
+
+  /** Converts this to a string for debugging purposes. */
+  toString() {
+    return (
+      "<Connection(" +
+      this.number +
+      (this.request ? ", " + this.request.path : "") +
+      "): " +
+      (this._closed ? "closed" : "open") +
+      ">"
+    );
+  },
+
+  requestStarted() {
+    this._requestStarted = true;
+  },
+};
+
+/** Returns an array of count bytes from the given input stream. */
+function readBytes(inputStream, count) {
+  return new BinaryInputStream(inputStream).readByteArray(count);
+}
+
+/** Request reader processing states; see RequestReader for details. */
+const READER_IN_REQUEST_LINE = 0;
+const READER_IN_HEADERS = 1;
+const READER_IN_BODY = 2;
+const READER_FINISHED = 3;
+
+/**
+ * Reads incoming request data asynchronously, does any necessary preprocessing,
+ * and forwards it to the request handler.  Processing occurs in three states:
+ *
+ *   READER_IN_REQUEST_LINE     Reading the request's status line
+ *   READER_IN_HEADERS          Reading headers in the request
+ *   READER_IN_BODY             Reading the body of the request
+ *   READER_FINISHED            Entire request has been read and processed
+ *
+ * During the first two stages, initial metadata about the request is gathered
+ * into a Request object.  Once the status line and headers have been processed,
+ * we start processing the body of the request into the Request.  Finally, when
+ * the entire body has been read, we create a Response and hand it off to the
+ * ServerHandler to be given to the appropriate request handler.
+ *
+ * @param connection : Connection
+ *   the connection for the request being read
+ */
+function RequestReader(connection) {
+  /** Connection metadata for this request. */
+  this._connection = connection;
+
+  /**
+   * A container providing line-by-line access to the raw bytes that make up the
+   * data which has been read from the connection but has not yet been acted
+   * upon (by passing it to the request handler or by extracting request
+   * metadata from it).
+   */
+  this._data = new LineData();
+
+  /**
+   * The amount of data remaining to be read from the body of this request.
+   * After all headers in the request have been read this is the value in the
+   * Content-Length header, but as the body is read its value decreases to zero.
+   */
+  this._contentLength = 0;
+
+  /** The current state of parsing the incoming request. */
+  this._state = READER_IN_REQUEST_LINE;
+
+  /** Metadata constructed from the incoming request for the request handler. */
+  this._metadata = new Request(connection.port);
+
+  /**
+   * Used to preserve state if we run out of line data midway through a
+   * multi-line header.  _lastHeaderName stores the name of the header, while
+   * _lastHeaderValue stores the value we've seen so far for the header.
+   *
+   * These fields are always either both undefined or both strings.
+   */
+  this._lastHeaderName = this._lastHeaderValue = undefined;
+}
+RequestReader.prototype = {
+  // NSIINPUTSTREAMCALLBACK
+
+  /**
+   * Called when more data from the incoming request is available.  This method
+   * then reads the available data from input and deals with that data as
+   * necessary, depending upon the syntax of already-downloaded data.
+   *
+   * @param input : nsIAsyncInputStream
+   *   the stream of incoming data from the connection
+   */
+  onInputStreamReady(input) {
+    dumpn(
+      "*** onInputStreamReady(input=" +
+        input +
+        ") on thread " +
+        Services.tm.currentThread +
+        " (main is " +
+        Services.tm.mainThread +
+        ")"
+    );
+    dumpn("*** this._state == " + this._state);
+
+    // Handle cases where we get more data after a request error has been
+    // discovered but *before* we can close the connection.
+    var data = this._data;
+    if (!data) {
+      return;
+    }
+
+    try {
+      data.appendBytes(readBytes(input, input.available()));
+    } catch (e) {
+      if (streamClosed(e)) {
+        dumpn(
+          "*** WARNING: unexpected error when reading from socket; will " +
+            "be treated as if the input stream had been closed"
+        );
+        dumpn("*** WARNING: actual error was: " + e);
+      }
+
+      // We've lost a race -- input has been closed, but we're still expecting
+      // to read more data.  available() will throw in this case, and since
+      // we're dead in the water now, destroy the connection.
+      dumpn(
+        "*** onInputStreamReady called on a closed input, destroying " +
+          "connection"
+      );
+      this._connection.close();
+      return;
+    }
+
+    switch (this._state) {
+      default:
+        NS_ASSERT(false, "invalid state: " + this._state);
+        break;
+
+      case READER_IN_REQUEST_LINE:
+        if (!this._processRequestLine()) {
+          break;
+        }
+      /* fall through */
+
+      case READER_IN_HEADERS:
+        if (!this._processHeaders()) {
+          break;
+        }
+      /* fall through */
+
+      case READER_IN_BODY:
+        this._processBody();
+    }
+
+    if (this._state != READER_FINISHED) {
+      input.asyncWait(this, 0, 0, Services.tm.currentThread);
+    }
+  },
+
+  //
+  // see nsISupports.QueryInterface
+  //
+  QueryInterface: ChromeUtils.generateQI(["nsIInputStreamCallback"]),
+
+  // PRIVATE API
+
+  /**
+   * Processes unprocessed, downloaded data as a request line.
+   *
+   * @returns boolean
+   *   true iff the request line has been fully processed
+   */
+  _processRequestLine() {
+    NS_ASSERT(this._state == READER_IN_REQUEST_LINE);
+
+    // Servers SHOULD ignore any empty line(s) received where a Request-Line
+    // is expected (section 4.1).
+    var data = this._data;
+    var line = {};
+    var readSuccess;
+    while ((readSuccess = data.readLine(line)) && line.value == "") {
+      dumpn("*** ignoring beginning blank line...");
+    }
+
+    // if we don't have a full line, wait until we do
+    if (!readSuccess) {
+      return false;
+    }
+
+    // we have the first non-blank line
+    try {
+      this._parseRequestLine(line.value);
+      this._state = READER_IN_HEADERS;
+      this._connection.requestStarted();
+      return true;
+    } catch (e) {
+      this._handleError(e);
+      return false;
+    }
+  },
+
+  /**
+   * Processes stored data, assuming it is either at the beginning or in
+   * the middle of processing request headers.
+   *
+   * @returns boolean
+   *   true iff header data in the request has been fully processed
+   */
+  _processHeaders() {
+    NS_ASSERT(this._state == READER_IN_HEADERS);
+
+    // XXX things to fix here:
+    //
+    // - need to support RFC 2047-encoded non-US-ASCII characters
+
+    try {
+      var done = this._parseHeaders();
+      if (done) {
+        var request = this._metadata;
+
+        // XXX this is wrong for requests with transfer-encodings applied to
+        //     them, particularly chunked (which by its nature can have no
+        //     meaningful Content-Length header)!
+        this._contentLength = request.hasHeader("Content-Length")
+          ? parseInt(request.getHeader("Content-Length"), 10)
+          : 0;
+        dumpn("_processHeaders, Content-length=" + this._contentLength);
+
+        this._state = READER_IN_BODY;
+      }
+      return done;
+    } catch (e) {
+      this._handleError(e);
+      return false;
+    }
+  },
+
+  /**
+   * Processes stored data, assuming it is either at the beginning or in
+   * the middle of processing the request body.
+   *
+   * @returns boolean
+   *   true iff the request body has been fully processed
+   */
+  _processBody() {
+    NS_ASSERT(this._state == READER_IN_BODY);
+
+    // XXX handle chunked transfer-coding request bodies!
+
+    try {
+      if (this._contentLength > 0) {
+        var data = this._data.purge();
+        var count = Math.min(data.length, this._contentLength);
+        dumpn(
+          "*** loading data=" +
+            data +
+            " len=" +
+            data.length +
+            " excess=" +
+            (data.length - count)
+        );
+        data.length = count;
+
+        var bos = new BinaryOutputStream(this._metadata._bodyOutputStream);
+        bos.writeByteArray(data);
+        this._contentLength -= count;
+      }
+
+      dumpn("*** remaining body data len=" + this._contentLength);
+      if (this._contentLength == 0) {
+        this._validateRequest();
+        this._state = READER_FINISHED;
+        this._handleResponse();
+        return true;
+      }
+
+      return false;
+    } catch (e) {
+      this._handleError(e);
+      return false;
+    }
+  },
+
+  /**
+   * Does various post-header checks on the data in this request.
+   *
+   * @throws : HttpError
+   *   if the request was malformed in some way
+   */
+  _validateRequest() {
+    NS_ASSERT(this._state == READER_IN_BODY);
+
+    dumpn("*** _validateRequest");
+
+    var metadata = this._metadata;
+    var headers = metadata._headers;
+
+    // 19.6.1.1 -- servers MUST report 400 to HTTP/1.1 requests w/o Host header
+    var identity = this._connection.server.identity;
+    if (metadata._httpVersion.atLeast(nsHttpVersion.HTTP_1_1)) {
+      if (!headers.hasHeader("Host")) {
+        dumpn("*** malformed HTTP/1.1 or greater request with no Host header!");
+        throw HTTP_400;
+      }
+
+      // If the Request-URI wasn't absolute, then we need to determine our host.
+      // We have to determine what scheme was used to access us based on the
+      // server identity data at this point, because the request just doesn't
+      // contain enough data on its own to do this, sadly.
+      if (!metadata._host) {
+        var host, port;
+        var hostPort = headers.getHeader("Host");
+        var colon = hostPort.lastIndexOf(":");
+        if (hostPort.lastIndexOf("]") > colon) {
+          colon = -1;
+        }
+        if (colon < 0) {
+          host = hostPort;
+          port = "";
+        } else {
+          host = hostPort.substring(0, colon);
+          port = hostPort.substring(colon + 1);
+        }
+
+        // NB: We allow an empty port here because, oddly, a colon may be
+        //     present even without a port number, e.g. "example.com:"; in this
+        //     case the default port applies.
+        if (!HOST_REGEX.test(host) || !/^\d*$/.test(port)) {
+          dumpn(
+            "*** malformed hostname (" +
+              hostPort +
+              ") in Host " +
+              "header, 400 time"
+          );
+          throw HTTP_400;
+        }
+
+        // If we're not given a port, we're stuck, because we don't know what
+        // scheme to use to look up the correct port here, in general.  Since
+        // the HTTPS case requires a tunnel/proxy and thus requires that the
+        // requested URI be absolute (and thus contain the necessary
+        // information), let's assume HTTP will prevail and use that.
+        port = +port || 80;
+
+        var scheme = identity.getScheme(host, port);
+        if (!scheme) {
+          dumpn(
+            "*** unrecognized hostname (" +
+              hostPort +
+              ") in Host " +
+              "header, 400 time"
+          );
+          throw HTTP_400;
+        }
+
+        metadata._scheme = scheme;
+        metadata._host = host;
+        metadata._port = port;
+      }
+    } else {
+      NS_ASSERT(
+        metadata._host === undefined,
+        "HTTP/1.0 doesn't allow absolute paths in the request line!"
+      );
+
+      metadata._scheme = identity.primaryScheme;
+      metadata._host = identity.primaryHost;
+      metadata._port = identity.primaryPort;
+    }
+
+    NS_ASSERT(
+      identity.has(metadata._scheme, metadata._host, metadata._port),
+      "must have a location we recognize by now!"
+    );
+  },
+
+  /**
+   * Handles responses in case of error, either in the server or in the request.
+   *
+   * @param e
+   *   the specific error encountered, which is an HttpError in the case where
+   *   the request is in some way invalid or cannot be fulfilled; if this isn't
+   *   an HttpError we're going to be paranoid and shut down, because that
+   *   shouldn't happen, ever
+   */
+  _handleError(e) {
+    // Don't fall back into normal processing!
+    this._state = READER_FINISHED;
+
+    var server = this._connection.server;
+    if (e instanceof HttpError) {
+      var code = e.code;
+    } else {
+      dumpn(
+        "!!! UNEXPECTED ERROR: " +
+          e +
+          (e.lineNumber ? ", line " + e.lineNumber : "")
+      );
+
+      // no idea what happened -- be paranoid and shut down
+      code = 500;
+      server._requestQuit();
+    }
+
+    // make attempted reuse of data an error
+    this._data = null;
+
+    this._connection.processError(code, this._metadata);
+  },
+
+  /**
+   * Now that we've read the request line and headers, we can actually hand off
+   * the request to be handled.
+   *
+   * This method is called once per request, after the request line and all
+   * headers and the body, if any, have been received.
+   */
+  _handleResponse() {
+    NS_ASSERT(this._state == READER_FINISHED);
+
+    // We don't need the line-based data any more, so make attempted reuse an
+    // error.
+    this._data = null;
+
+    this._connection.process(this._metadata);
+  },
+
+  // PARSING
+
+  /**
+   * Parses the request line for the HTTP request associated with this.
+   *
+   * @param line : string
+   *   the request line
+   */
+  _parseRequestLine(line) {
+    NS_ASSERT(this._state == READER_IN_REQUEST_LINE);
+
+    dumpn("*** _parseRequestLine('" + line + "')");
+
+    var metadata = this._metadata;
+
+    // clients and servers SHOULD accept any amount of SP or HT characters
+    // between fields, even though only a single SP is required (section 19.3)
+    var request = line.split(/[ \t]+/);
+    if (!request || request.length != 3) {
+      dumpn("*** No request in line");
+      throw HTTP_400;
+    }
+
+    metadata._method = request[0];
+
+    // get the HTTP version
+    var ver = request[2];
+    var match = ver.match(/^HTTP\/(\d+\.\d+)$/);
+    if (!match) {
+      dumpn("*** No HTTP version in line");
+      throw HTTP_400;
+    }
+
+    // determine HTTP version
+    try {
+      metadata._httpVersion = new nsHttpVersion(match[1]);
+      if (!metadata._httpVersion.atLeast(nsHttpVersion.HTTP_1_0)) {
+        throw new Error("unsupported HTTP version");
+      }
+    } catch (e) {
+      // we support HTTP/1.0 and HTTP/1.1 only
+      throw HTTP_501;
+    }
+
+    var fullPath = request[1];
+
+    if (metadata._method == "CONNECT") {
+      metadata._path = "CONNECT";
+      metadata._scheme = "https";
+      [metadata._host, metadata._port] = fullPath.split(":");
+      return;
+    }
+
+    var serverIdentity = this._connection.server.identity;
+    var scheme, host, port;
+
+    if (fullPath.charAt(0) != "/") {
+      // No absolute paths in the request line in HTTP prior to 1.1
+      if (!metadata._httpVersion.atLeast(nsHttpVersion.HTTP_1_1)) {
+        dumpn("*** Metadata version too low");
+        throw HTTP_400;
+      }
+
+      try {
+        var uri = Services.io.newURI(fullPath);
+        fullPath = uri.pathQueryRef;
+        scheme = uri.scheme;
+        host = uri.asciiHost;
+        if (host.includes(":")) {
+          // If the host still contains a ":", then it is an IPv6 address.
+          // IPv6 addresses-as-host are registered with brackets, so we need to
+          // wrap the host in brackets because nsIURI's host lacks them.
+          // This inconsistency in nsStandardURL is tracked at bug 1195459.
+          host = `[${host}]`;
+        }
+        metadata._host = host;
+        port = uri.port;
+        if (port === -1) {
+          if (scheme === "http") {
+            port = 80;
+          } else if (scheme === "https") {
+            port = 443;
+          } else {
+            dumpn("*** Unknown scheme: " + scheme);
+            throw HTTP_400;
+          }
+        }
+      } catch (e) {
+        // If the host is not a valid host on the server, the response MUST be a
+        // 400 (Bad Request) error message (section 5.2).  Alternately, the URI
+        // is malformed.
+        dumpn("*** Threw when dealing with URI: " + e);
+        throw HTTP_400;
+      }
+
+      if (
+        !serverIdentity.has(scheme, host, port) ||
+        fullPath.charAt(0) != "/"
+      ) {
+        dumpn("*** serverIdentity unknown or path does not start with '/'");
+        throw HTTP_400;
+      }
+    }
+
+    var splitter = fullPath.indexOf("?");
+    if (splitter < 0) {
+      // _queryString already set in ctor
+      metadata._path = fullPath;
+    } else {
+      metadata._path = fullPath.substring(0, splitter);
+      metadata._queryString = fullPath.substring(splitter + 1);
+    }
+
+    metadata._scheme = scheme;
+    metadata._host = host;
+    metadata._port = port;
+  },
+
+  /**
+   * Parses all available HTTP headers in this until the header-ending CRLFCRLF,
+   * adding them to the store of headers in the request.
+   *
+   * @throws
+   *   HTTP_400 if the headers are malformed
+   * @returns boolean
+   *   true if all headers have now been processed, false otherwise
+   */
+  _parseHeaders() {
+    NS_ASSERT(this._state == READER_IN_HEADERS);
+
+    dumpn("*** _parseHeaders");
+
+    var data = this._data;
+
+    var headers = this._metadata._headers;
+    var lastName = this._lastHeaderName;
+    var lastVal = this._lastHeaderValue;
+
+    var line = {};
+    while (true) {
+      dumpn("*** Last name: '" + lastName + "'");
+      dumpn("*** Last val: '" + lastVal + "'");
+      NS_ASSERT(
+        !((lastVal === undefined) ^ (lastName === undefined)),
+        lastName === undefined
+          ? "lastVal without lastName?  lastVal: '" + lastVal + "'"
+          : "lastName without lastVal?  lastName: '" + lastName + "'"
+      );
+
+      if (!data.readLine(line)) {
+        // save any data we have from the header we might still be processing
+        this._lastHeaderName = lastName;
+        this._lastHeaderValue = lastVal;
+        return false;
+      }
+
+      var lineText = line.value;
+      dumpn("*** Line text: '" + lineText + "'");
+      var firstChar = lineText.charAt(0);
+
+      // blank line means end of headers
+      if (lineText == "") {
+        // we're finished with the previous header
+        if (lastName) {
+          try {
+            headers.setHeader(lastName, lastVal, true);
+          } catch (e) {
+            dumpn("*** setHeader threw on last header, e == " + e);
+            throw HTTP_400;
+          }
+        } else {
+          // no headers in request -- valid for HTTP/1.0 requests
+        }
+
+        // either way, we're done processing headers
+        this._state = READER_IN_BODY;
+        return true;
+      } else if (firstChar == " " || firstChar == "\t") {
+        // multi-line header if we've already seen a header line
+        if (!lastName) {
+          dumpn("We don't have a header to continue!");
+          throw HTTP_400;
+        }
+
+        // append this line's text to the value; starts with SP/HT, so no need
+        // for separating whitespace
+        lastVal += lineText;
+      } else {
+        // we have a new header, so set the old one (if one existed)
+        if (lastName) {
+          try {
+            headers.setHeader(lastName, lastVal, true);
+          } catch (e) {
+            dumpn("*** setHeader threw on a header, e == " + e);
+            throw HTTP_400;
+          }
+        }
+
+        var colon = lineText.indexOf(":"); // first colon must be splitter
+        if (colon < 1) {
+          dumpn("*** No colon or missing header field-name");
+          throw HTTP_400;
+        }
+
+        // set header name, value (to be set in the next loop, usually)
+        lastName = lineText.substring(0, colon);
+        lastVal = lineText.substring(colon + 1);
+      } // empty, continuation, start of header
+    } // while (true)
+  },
+};
+
+/** The character codes for CR and LF. */
+const CR = 0x0d,
+  LF = 0x0a;
+
+/**
+ * Calculates the number of characters before the first CRLF pair in array, or
+ * -1 if the array contains no CRLF pair.
+ *
+ * @param array : Array
+ *   an array of numbers in the range [0, 256), each representing a single
+ *   character; the first CRLF is the lowest index i where
+ *   |array[i] == "\r".charCodeAt(0)| and |array[i+1] == "\n".charCodeAt(0)|,
+ *   if such an |i| exists, and -1 otherwise
+ * @param start : uint
+ *   start index from which to begin searching in array
+ * @returns int
+ *   the index of the first CRLF if any were present, -1 otherwise
+ */
+function findCRLF(array, start) {
+  for (var i = array.indexOf(CR, start); i >= 0; i = array.indexOf(CR, i + 1)) {
+    if (array[i + 1] == LF) {
+      return i;
+    }
+  }
+  return -1;
+}
+
+/**
+ * A container which provides line-by-line access to the arrays of bytes with
+ * which it is seeded.
+ */
+export function LineData() {
+  /** An array of queued bytes from which to get line-based characters. */
+  this._data = [];
+
+  /** Start index from which to search for CRLF. */
+  this._start = 0;
+}
+LineData.prototype = {
+  /**
+   * Appends the bytes in the given array to the internal data cache maintained
+   * by this.
+   */
+  appendBytes(bytes) {
+    var count = bytes.length;
+    var quantum = 262144; // just above half SpiderMonkey's argument-count limit
+    if (count < quantum) {
+      Array.prototype.push.apply(this._data, bytes);
+      return;
+    }
+
+    // Large numbers of bytes may cause Array.prototype.push to be called with
+    // more arguments than the JavaScript engine supports.  In that case append
+    // bytes in fixed-size amounts until all bytes are appended.
+    for (var start = 0; start < count; start += quantum) {
+      var slice = bytes.slice(start, Math.min(start + quantum, count));
+      Array.prototype.push.apply(this._data, slice);
+    }
+  },
+
+  /**
+   * Removes and returns a line of data, delimited by CRLF, from this.
+   *
+   * @param out
+   *   an object whose "value" property will be set to the first line of text
+   *   present in this, sans CRLF, if this contains a full CRLF-delimited line
+   *   of text; if this doesn't contain enough data, the value of the property
+   *   is undefined
+   * @returns boolean
+   *   true if a full line of data could be read from the data in this, false
+   *   otherwise
+   */
+  readLine(out) {
+    var data = this._data;
+    var length = findCRLF(data, this._start);
+    if (length < 0) {
+      this._start = data.length;
+
+      // But if our data ends in a CR, we have to back up one, because
+      // the first byte in the next packet might be an LF and if we
+      // start looking at data.length we won't find it.
+      if (data.length && data[data.length - 1] === CR) {
+        --this._start;
+      }
+
+      return false;
+    }
+
+    // Reset for future lines.
+    this._start = 0;
+
+    //
+    // We have the index of the CR, so remove all the characters, including
+    // CRLF, from the array with splice, and convert the removed array
+    // (excluding the trailing CRLF characters) into the corresponding string.
+    //
+    var leading = data.splice(0, length + 2);
+    var quantum = 262144;
+    var line = "";
+    for (var start = 0; start < length; start += quantum) {
+      var slice = leading.slice(start, Math.min(start + quantum, length));
+      line += String.fromCharCode.apply(null, slice);
+    }
+
+    out.value = line;
+    return true;
+  },
+
+  /**
+   * Removes the bytes currently within this and returns them in an array.
+   *
+   * @returns Array
+   *   the bytes within this when this method is called
+   */
+  purge() {
+    var data = this._data;
+    this._data = [];
+    return data;
+  },
+};
+
+/**
+ * Creates a request-handling function for an nsIHttpRequestHandler object.
+ */
+function createHandlerFunc(handler) {
+  return function (metadata, response) {
+    handler.handle(metadata, response);
+  };
+}
+
+/**
+ * The default handler for directories; writes an HTML response containing a
+ * slightly-formatted directory listing.
+ */
+function defaultIndexHandler(metadata, response) {
+  response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+  var path = htmlEscape(decodeURI(metadata.path));
+
+  //
+  // Just do a very basic bit of directory listings -- no need for too much
+  // fanciness, especially since we don't have a style sheet in which we can
+  // stick rules (don't want to pollute the default path-space).
+  //
+
+  var body =
+    "<html>\
+                <head>\
+                  <title>" +
+    path +
+    "</title>\
+                </head>\
+                <body>\
+                  <h1>" +
+    path +
+    '</h1>\
+                  <ol style="list-style-type: none">';
+
+  var directory = metadata.getProperty("directory");
+  NS_ASSERT(directory && directory.isDirectory());
+
+  var fileList = [];
+  var files = directory.directoryEntries;
+  while (files.hasMoreElements()) {
+    var f = files.nextFile;
+    let name = f.leafName;
+    if (
+      !f.isHidden() &&
+      (name.charAt(name.length - 1) != HIDDEN_CHAR ||
+        name.charAt(name.length - 2) == HIDDEN_CHAR)
+    ) {
+      fileList.push(f);
+    }
+  }
+
+  fileList.sort(fileSort);
+
+  for (var i = 0; i < fileList.length; i++) {
+    var file = fileList[i];
+    try {
+      let name = file.leafName;
+      if (name.charAt(name.length - 1) == HIDDEN_CHAR) {
+        name = name.substring(0, name.length - 1);
+      }
+      var sep = file.isDirectory() ? "/" : "";
+
+      // Note: using " to delimit the attribute here because encodeURIComponent
+      //       passes through '.
+      var item =
+        '<li><a href="' +
+        encodeURIComponent(name) +
+        sep +
+        '">' +
+        htmlEscape(name) +
+        sep +
+        "</a></li>";
+
+      body += item;
+    } catch (e) {
+      /* some file system error, ignore the file */
+    }
+  }
+
+  body +=
+    "    </ol>\
+                </body>\
+              </html>";
+
+  response.bodyOutputStream.write(body, body.length);
+}
+
+/**
+ * Sorts a and b (nsIFile objects) into an aesthetically pleasing order.
+ */
+function fileSort(a, b) {
+  var dira = a.isDirectory(),
+    dirb = b.isDirectory();
+
+  if (dira && !dirb) {
+    return -1;
+  }
+  if (dirb && !dira) {
+    return 1;
+  }
+
+  var namea = a.leafName.toLowerCase(),
+    nameb = b.leafName.toLowerCase();
+  return nameb > namea ? -1 : 1;
+}
+
+/**
+ * Converts an externally-provided path into an internal path for use in
+ * determining file mappings.
+ *
+ * @param path
+ *   the path to convert
+ * @param encoded
+ *   true if the given path should be passed through decodeURI prior to
+ *   conversion
+ * @throws URIError
+ *   if path is incorrectly encoded
+ */
+function toInternalPath(path, encoded) {
+  if (encoded) {
+    path = decodeURI(path);
+  }
+
+  var comps = path.split("/");
+  for (var i = 0, sz = comps.length; i < sz; i++) {
+    var comp = comps[i];
+    if (comp.charAt(comp.length - 1) == HIDDEN_CHAR) {
+      comps[i] = comp + HIDDEN_CHAR;
+    }
+  }
+  return comps.join("/");
+}
+
+const PERMS_READONLY = (4 << 6) | (4 << 3) | 4;
+
+/**
+ * Adds custom-specified headers for the given file to the given response, if
+ * any such headers are specified.
+ *
+ * @param file
+ *   the file on the disk which is to be written
+ * @param metadata
+ *   metadata about the incoming request
+ * @param response
+ *   the Response to which any specified headers/data should be written
+ * @throws HTTP_500
+ *   if an error occurred while processing custom-specified headers
+ */
+function maybeAddHeadersInternal(
+  file,
+  metadata,
+  response,
+  informationalResponse
+) {
+  var name = file.leafName;
+  if (name.charAt(name.length - 1) == HIDDEN_CHAR) {
+    name = name.substring(0, name.length - 1);
+  }
+
+  var headerFile = file.parent;
+  if (!informationalResponse) {
+    headerFile.append(name + HEADERS_SUFFIX);
+  } else {
+    headerFile.append(name + INFORMATIONAL_RESPONSE_SUFFIX);
+  }
+
+  if (!headerFile.exists()) {
+    return;
+  }
+
+  const PR_RDONLY = 0x01;
+  var fis = new FileInputStream(
+    headerFile,
+    PR_RDONLY,
+    PERMS_READONLY,
+    Ci.nsIFileInputStream.CLOSE_ON_EOF
+  );
+
+  try {
+    var lis = new ConverterInputStream(fis, "UTF-8", 1024, 0x0);
+    lis.QueryInterface(Ci.nsIUnicharLineInputStream);
+
+    var line = { value: "" };
+    var more = lis.readLine(line);
+
+    if (!more && line.value == "") {
+      return;
+    }
+
+    // request line
+
+    var status = line.value;
+    if (status.indexOf("HTTP ") == 0) {
+      status = status.substring(5);
+      var space = status.indexOf(" ");
+      var code, description;
+      if (space < 0) {
+        code = status;
+        description = "";
+      } else {
+        code = status.substring(0, space);
+        description = status.substring(space + 1, status.length);
+      }
+
+      if (!informationalResponse) {
+        response.setStatusLine(
+          metadata.httpVersion,
+          parseInt(code, 10),
+          description
+        );
+      } else {
+        response.setInformationalResponseStatusLine(
+          metadata.httpVersion,
+          parseInt(code, 10),
+          description
+        );
+      }
+
+      line.value = "";
+      more = lis.readLine(line);
+    } else if (informationalResponse) {
+      // An informational response must have a status line.
+      return;
+    }
+
+    // headers
+    while (more || line.value != "") {
+      var header = line.value;
+      var colon = header.indexOf(":");
+
+      if (!informationalResponse) {
+        response.setHeader(
+          header.substring(0, colon),
+          header.substring(colon + 1, header.length),
+          false
+        ); // allow overriding server-set headers
+      } else {
+        response.setInformationalResponseHeader(
+          header.substring(0, colon),
+          header.substring(colon + 1, header.length),
+          false
+        ); // allow overriding server-set headers
+      }
+
+      line.value = "";
+      more = lis.readLine(line);
+    }
+  } catch (e) {
+    dumpn("WARNING: error in headers for " + metadata.path + ": " + e);
+    throw HTTP_500;
+  } finally {
+    fis.close();
+  }
+}
+
+function maybeAddHeaders(file, metadata, response) {
+  maybeAddHeadersInternal(file, metadata, response, false);
+}
+
+function maybeAddInformationalResponse(file, metadata, response) {
+  maybeAddHeadersInternal(file, metadata, response, true);
+}
+
+/**
+ * An object which handles requests for a server, executing default and
+ * overridden behaviors as instructed by the code which uses and manipulates it.
+ * Default behavior includes the paths / and /trace (diagnostics), with some
+ * support for HTTP error pages for various codes and fallback to HTTP 500 if
+ * those codes fail for any reason.
+ *
+ * @param server : nsHttpServer
+ *   the server in which this handler is being used
+ */
+function ServerHandler(server) {
+  // FIELDS
+
+  /**
+   * The nsHttpServer instance associated with this handler.
+   */
+  this._server = server;
+
+  /**
+   * A FileMap object containing the set of path->nsIFile mappings for
+   * all directory mappings set in the server (e.g., "/" for /var/www/html/,
+   * "/foo/bar/" for /local/path/, and "/foo/bar/baz/" for /local/path2).
+   *
+   * Note carefully: the leading and trailing "/" in each path (not file) are
+   * removed before insertion to simplify the code which uses this.  You have
+   * been warned!
+   */
+  this._pathDirectoryMap = new FileMap();
+
+  /**
+   * Custom request handlers for the server in which this resides.  Path-handler
+   * pairs are stored as property-value pairs in this property.
+   *
+   * @see ServerHandler.prototype._defaultPaths
+   */
+  this._overridePaths = {};
+
+  /**
+   * Custom request handlers for the path prefixes on the server in which this
+   * resides.  Path-handler pairs are stored as property-value pairs in this
+   * property.
+   *
+   * @see ServerHandler.prototype._defaultPaths
+   */
+  this._overridePrefixes = {};
+
+  /**
+   * Custom request handlers for the error handlers in the server in which this
+   * resides.  Path-handler pairs are stored as property-value pairs in this
+   * property.
+   *
+   * @see ServerHandler.prototype._defaultErrors
+   */
+  this._overrideErrors = {};
+
+  /**
+   * Maps file extensions to their MIME types in the server, overriding any
+   * mapping that might or might not exist in the MIME service.
+   */
+  this._mimeMappings = {};
+
+  /**
+   * The default handler for requests for directories, used to serve directories
+   * when no index file is present.
+   */
+  this._indexHandler = defaultIndexHandler;
+
+  /** Per-path state storage for the server. */
+  this._state = {};
+
+  /** Entire-server state storage. */
+  this._sharedState = {};
+
+  /** Entire-server state storage for nsISupports values. */
+  this._objectState = {};
+}
+ServerHandler.prototype = {
+  // PUBLIC API
+
+  /**
+   * Handles a request to this server, responding to the request appropriately
+   * and initiating server shutdown if necessary.
+   *
+   * This method never throws an exception.
+   *
+   * @param connection : Connection
+   *   the connection for this request
+   */
+  handleResponse(connection) {
+    var request = connection.request;
+    var response = new Response(connection);
+
+    var path = request.path;
+    dumpn("*** path == " + path);
+
+    try {
+      try {
+        if (path in this._overridePaths) {
+          // explicit paths first, then files based on existing directory mappings,
+          // then (if the file doesn't exist) built-in server default paths
+          dumpn("calling override for " + path);
+          this._overridePaths[path](request, response);
+        } else {
+          var longestPrefix = "";
+          for (let prefix in this._overridePrefixes) {
+            if (
+              prefix.length > longestPrefix.length &&
+              path.substr(0, prefix.length) == prefix
+            ) {
+              longestPrefix = prefix;
+            }
+          }
+          if (longestPrefix.length) {
+            dumpn("calling prefix override for " + longestPrefix);
+            this._overridePrefixes[longestPrefix](request, response);
+          } else {
+            this._handleDefault(request, response);
+          }
+        }
+      } catch (e) {
+        if (response.partiallySent()) {
+          response.abort(e);
+          return;
+        }
+
+        if (!(e instanceof HttpError)) {
+          dumpn("*** unexpected error: e == " + e);
+          throw HTTP_500;
+        }
+        if (e.code !== 404) {
+          throw e;
+        }
+
+        dumpn("*** default: " + (path in this._defaultPaths));
+
+        response = new Response(connection);
+        if (path in this._defaultPaths) {
+          this._defaultPaths[path](request, response);
+        } else {
+          throw HTTP_404;
+        }
+      }
+    } catch (e) {
+      if (response.partiallySent()) {
+        response.abort(e);
+        return;
+      }
+
+      var errorCode = "internal";
+
+      try {
+        if (!(e instanceof HttpError)) {
+          throw e;
+        }
+
+        errorCode = e.code;
+        dumpn("*** errorCode == " + errorCode);
+
+        response = new Response(connection);
+        if (e.customErrorHandling) {
+          e.customErrorHandling(response);
+        }
+        this._handleError(errorCode, request, response);
+        return;
+      } catch (e2) {
+        dumpn(
+          "*** error handling " +
+            errorCode +
+            " error: " +
+            "e2 == " +
+            e2 +
+            ", shutting down server"
+        );
+
+        connection.server._requestQuit();
+        response.abort(e2);
+        return;
+      }
+    }
+
+    response.complete();
+  },
+
+  //
+  // see nsIHttpServer.registerFile
+  //
+  registerFile(path, file, handler) {
+    if (!file) {
+      dumpn("*** unregistering '" + path + "' mapping");
+      delete this._overridePaths[path];
+      return;
+    }
+
+    dumpn("*** registering '" + path + "' as mapping to " + file.path);
+    file = file.clone();
+
+    var self = this;
+    this._overridePaths[path] = function (request, response) {
+      if (!file.exists()) {
+        throw HTTP_404;
+      }
+
+      dumpn("*** responding '" + path + "' as mapping to " + file.path);
+
+      response.setStatusLine(request.httpVersion, 200, "OK");
+      if (typeof handler === "function") {
+        handler(request, response);
+      }
+      self._writeFileResponse(request, file, response, 0, file.fileSize);
+    };
+  },
+
+  //
+  // see nsIHttpServer.registerPathHandler
+  //
+  registerPathHandler(path, handler) {
+    if (!path.length) {
+      throw Components.Exception(
+        "Handler path cannot be empty",
+        Cr.NS_ERROR_INVALID_ARG
+      );
+    }
+
+    // XXX true path validation!
+    if (path.charAt(0) != "/" && path != "CONNECT") {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    this._handlerToField(handler, this._overridePaths, path);
+  },
+
+  //
+  // see nsIHttpServer.registerPrefixHandler
+  //
+  registerPrefixHandler(path, handler) {
+    // XXX true path validation!
+    if (path.charAt(0) != "/" || path.charAt(path.length - 1) != "/") {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    this._handlerToField(handler, this._overridePrefixes, path);
+  },
+
+  //
+  // see nsIHttpServer.registerDirectory
+  //
+  registerDirectory(path, directory) {
+    // strip off leading and trailing '/' so that we can use lastIndexOf when
+    // determining exactly how a path maps onto a mapped directory --
+    // conditional is required here to deal with "/".substring(1, 0) being
+    // converted to "/".substring(0, 1) per the JS specification
+    var key = path.length == 1 ? "" : path.substring(1, path.length - 1);
+
+    // the path-to-directory mapping code requires that the first character not
+    // be "/", or it will go into an infinite loop
+    if (key.charAt(0) == "/") {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    key = toInternalPath(key, false);
+
+    if (directory) {
+      dumpn("*** mapping '" + path + "' to the location " + directory.path);
+      this._pathDirectoryMap.put(key, directory);
+    } else {
+      dumpn("*** removing mapping for '" + path + "'");
+      this._pathDirectoryMap.put(key, null);
+    }
+  },
+
+  //
+  // see nsIHttpServer.registerErrorHandler
+  //
+  registerErrorHandler(err, handler) {
+    if (!(err in HTTP_ERROR_CODES)) {
+      dumpn(
+        "*** WARNING: registering non-HTTP/1.1 error code " +
+          "(" +
+          err +
+          ") handler -- was this intentional?"
+      );
+    }
+
+    this._handlerToField(handler, this._overrideErrors, err);
+  },
+
+  //
+  // see nsIHttpServer.setIndexHandler
+  //
+  setIndexHandler(handler) {
+    if (!handler) {
+      handler = defaultIndexHandler;
+    } else if (typeof handler != "function") {
+      handler = createHandlerFunc(handler);
+    }
+
+    this._indexHandler = handler;
+  },
+
+  //
+  // see nsIHttpServer.registerContentType
+  //
+  registerContentType(ext, type) {
+    if (!type) {
+      delete this._mimeMappings[ext];
+    } else {
+      this._mimeMappings[ext] = headerUtils.normalizeFieldValue(type);
+    }
+  },
+
+  // PRIVATE API
+
+  /**
+   * Sets or remove (if handler is null) a handler in an object with a key.
+   *
+   * @param handler
+   *   a handler, either function or an nsIHttpRequestHandler
+   * @param dict
+   *   The object to attach the handler to.
+   * @param key
+   *   The field name of the handler.
+   */
+  _handlerToField(handler, dict, key) {
+    // for convenience, handler can be a function if this is run from xpcshell
+    if (typeof handler == "function") {
+      dict[key] = handler;
+    } else if (handler) {
+      dict[key] = createHandlerFunc(handler);
+    } else {
+      delete dict[key];
+    }
+  },
+
+  /**
+   * Handles a request which maps to a file in the local filesystem (if a base
+   * path has already been set; otherwise the 404 error is thrown).
+   *
+   * @param metadata : Request
+   *   metadata for the incoming request
+   * @param response : Response
+   *   an uninitialized Response to the given request, to be initialized by a
+   *   request handler
+   * @throws HTTP_###
+   *   if an HTTP error occurred (usually HTTP_404); note that in this case the
+   *   calling code must handle post-processing of the response
+   */
+  _handleDefault(metadata, response) {
+    dumpn("*** _handleDefault()");
+
+    response.setStatusLine(metadata.httpVersion, 200, "OK");
+
+    var path = metadata.path;
+    NS_ASSERT(path.charAt(0) == "/", "invalid path: <" + path + ">");
+
+    // determine the actual on-disk file; this requires finding the deepest
+    // path-to-directory mapping in the requested URL
+    var file = this._getFileForPath(path);
+
+    // the "file" might be a directory, in which case we either serve the
+    // contained index.html or make the index handler write the response
+    if (file.exists() && file.isDirectory()) {
+      file.append("index.html"); // make configurable?
+      if (!file.exists() || file.isDirectory()) {
+        metadata._ensurePropertyBag();
+        metadata._bag.setPropertyAsInterface("directory", file.parent);
+        this._indexHandler(metadata, response);
+        return;
+      }
+    }
+
+    // alternately, the file might not exist
+    if (!file.exists()) {
+      throw HTTP_404;
+    }
+
+    var start, end;
+    if (
+      metadata._httpVersion.atLeast(nsHttpVersion.HTTP_1_1) &&
+      metadata.hasHeader("Range") &&
+      this._getTypeFromFile(file) !== SJS_TYPE
+    ) {
+      var rangeMatch = metadata
+        .getHeader("Range")
+        .match(/^bytes=(\d+)?-(\d+)?$/);
+      if (!rangeMatch) {
+        dumpn(
+          "*** Range header bogosity: '" + metadata.getHeader("Range") + "'"
+        );
+        throw HTTP_400;
+      }
+
+      if (rangeMatch[1] !== undefined) {
+        start = parseInt(rangeMatch[1], 10);
+      }
+
+      if (rangeMatch[2] !== undefined) {
+        end = parseInt(rangeMatch[2], 10);
+      }
+
+      if (start === undefined && end === undefined) {
+        dumpn(
+          "*** More Range header bogosity: '" +
+            metadata.getHeader("Range") +
+            "'"
+        );
+        throw HTTP_400;
+      }
+
+      // No start given, so the end is really the count of bytes from the
+      // end of the file.
+      if (start === undefined) {
+        start = Math.max(0, file.fileSize - end);
+        end = file.fileSize - 1;
+      }
+
+      // start and end are inclusive
+      if (end === undefined || end >= file.fileSize) {
+        end = file.fileSize - 1;
+      }
+
+      if (start !== undefined && start >= file.fileSize) {
+        var HTTP_416 = new HttpError(416, "Requested Range Not Satisfiable");
+        HTTP_416.customErrorHandling = function (errorResponse) {
+          maybeAddHeaders(file, metadata, errorResponse);
+        };
+        throw HTTP_416;
+      }
+
+      if (end < start) {
+        response.setStatusLine(metadata.httpVersion, 200, "OK");
+        start = 0;
+        end = file.fileSize - 1;
+      } else {
+        response.setStatusLine(metadata.httpVersion, 206, "Partial Content");
+        var contentRange = "bytes " + start + "-" + end + "/" + file.fileSize;
+        response.setHeader("Content-Range", contentRange);
+      }
+    } else {
+      start = 0;
+      end = file.fileSize - 1;
+    }
+
+    // finally...
+    dumpn(
+      "*** handling '" +
+        path +
+        "' as mapping to " +
+        file.path +
+        " from " +
+        start +
+        " to " +
+        end +
+        " inclusive"
+    );
+    this._writeFileResponse(metadata, file, response, start, end - start + 1);
+  },
+
+  /**
+   * Writes an HTTP response for the given file, including setting headers for
+   * file metadata.
+   *
+   * @param metadata : Request
+   *   the Request for which a response is being generated
+   * @param file : nsIFile
+   *   the file which is to be sent in the response
+   * @param response : Response
+   *   the response to which the file should be written
+   * @param offset: uint
+   *   the byte offset to skip to when writing
+   * @param count: uint
+   *   the number of bytes to write
+   */
+  _writeFileResponse(metadata, file, response, offset, count) {
+    const PR_RDONLY = 0x01;
+
+    var type = this._getTypeFromFile(file);
+    if (type === SJS_TYPE) {
+      let fis = new FileInputStream(
+        file,
+        PR_RDONLY,
+        PERMS_READONLY,
+        Ci.nsIFileInputStream.CLOSE_ON_EOF
+      );
+
+      try {
+        // If you update the list of imports, please update the list in
+        // tools/lint/eslint/eslint-plugin-mozilla/lib/environments/sjs.js
+        // as well.
+        var s = Cu.Sandbox(Cu.getGlobalForObject({}), {
+          wantGlobalProperties: [
+            "atob",
+            "btoa",
+            "ChromeUtils",
+            "IOUtils",
+            "PathUtils",
+            "TextDecoder",
+            "TextEncoder",
+            "URLSearchParams",
+            "URL",
+          ],
+        });
+        s.importFunction(dump, "dump");
+        s.importFunction(Services, "Services");
+
+        // Define a basic key-value state-preservation API across requests, with
+        // keys initially corresponding to the empty string.
+        var self = this;
+        var path = metadata.path;
+        s.importFunction(function getState(k) {
+          return self._getState(path, k);
+        });
+        s.importFunction(function setState(k, v) {
+          self._setState(path, k, v);
+        });
+        s.importFunction(function getSharedState(k) {
+          return self._getSharedState(k);
+        });
+        s.importFunction(function setSharedState(k, v) {
+          self._setSharedState(k, v);
+        });
+        s.importFunction(function getObjectState(k, callback) {
+          callback(self._getObjectState(k));
+        });
+        s.importFunction(function setObjectState(k, v) {
+          self._setObjectState(k, v);
+        });
+        s.importFunction(function registerPathHandler(p, h) {
+          self.registerPathHandler(p, h);
+        });
+
+        // Make it possible for sjs files to access their location
+        this._setState(path, "__LOCATION__", file.path);
+
+        try {
+          // Alas, the line number in errors dumped to console when calling the
+          // request handler is simply an offset from where we load the SJS file.
+          // Work around this in a reasonably non-fragile way by dynamically
+          // getting the line number where we evaluate the SJS file.  Don't
+          // separate these two lines!
+          var line = new Error().lineNumber;
+          let uri = Services.io.newFileURI(file);
+          Services.scriptloader.loadSubScript(uri.spec, s);
+        } catch (e) {
+          dumpn("*** syntax error in SJS at " + file.path + ": " + e);
+          throw HTTP_500;
+        }
+
+        try {
+          s.handleRequest(metadata, response);
+        } catch (e) {
+          dump(
+            "*** error running SJS at " +
+              file.path +
+              ": " +
+              e +
+              " on line " +
+              (e instanceof Error
+                ? e.lineNumber + " in httpd.js"
+                : e.lineNumber - line) +
+              "\n"
+          );
+          throw HTTP_500;
+        }
+      } finally {
+        fis.close();
+      }
+    } else {
+      try {
+        response.setHeader(
+          "Last-Modified",
+          toDateString(file.lastModifiedTime),
+          false
+        );
+      } catch (e) {
+        /* lastModifiedTime threw, ignore */
+      }
+
+      response.setHeader("Content-Type", type, false);
+      maybeAddInformationalResponse(file, metadata, response);
+      maybeAddHeaders(file, metadata, response);
+      // Allow overriding Content-Length
+      try {
+        response.getHeader("Content-Length");
+      } catch (e) {
+        response.setHeader("Content-Length", "" + count, false);
+      }
+
+      let fis = new FileInputStream(
+        file,
+        PR_RDONLY,
+        PERMS_READONLY,
+        Ci.nsIFileInputStream.CLOSE_ON_EOF
+      );
+
+      offset = offset || 0;
+      count = count || file.fileSize;
+      NS_ASSERT(offset === 0 || offset < file.fileSize, "bad offset");
+      NS_ASSERT(count >= 0, "bad count");
+      NS_ASSERT(offset + count <= file.fileSize, "bad total data size");
+
+      try {
+        if (offset !== 0) {
+          // Seek (or read, if seeking isn't supported) to the correct offset so
+          // the data sent to the client matches the requested range.
+          if (fis instanceof Ci.nsISeekableStream) {
+            fis.seek(Ci.nsISeekableStream.NS_SEEK_SET, offset);
+          } else {
+            new ScriptableInputStream(fis).read(offset);
+          }
+        }
+      } catch (e) {
+        fis.close();
+        throw e;
+      }
+
+      let writeMore = function () {
+        Services.tm.currentThread.dispatch(
+          writeData,
+          Ci.nsIThread.DISPATCH_NORMAL
+        );
+      };
+
+      var input = new BinaryInputStream(fis);
+      var output = new BinaryOutputStream(response.bodyOutputStream);
+      var writeData = {
+        run() {
+          var chunkSize = Math.min(65536, count);
+          count -= chunkSize;
+          NS_ASSERT(count >= 0, "underflow");
+
+          try {
+            var data = input.readByteArray(chunkSize);
+            NS_ASSERT(
+              data.length === chunkSize,
+              "incorrect data returned?  got " +
+                data.length +
+                ", expected " +
+                chunkSize
+            );
+            output.writeByteArray(data);
+            if (count === 0) {
+              fis.close();
+              response.finish();
+            } else {
+              writeMore();
+            }
+          } catch (e) {
+            try {
+              fis.close();
+            } finally {
+              response.finish();
+            }
+            throw e;
+          }
+        },
+      };
+
+      writeMore();
+
+      // Now that we know copying will start, flag the response as async.
+      response.processAsync();
+    }
+  },
+
+  /**
+   * Get the value corresponding to a given key for the given path for SJS state
+   * preservation across requests.
+   *
+   * @param path : string
+   *   the path from which the given state is to be retrieved
+   * @param k : string
+   *   the key whose corresponding value is to be returned
+   * @returns string
+   *   the corresponding value, which is initially the empty string
+   */
+  _getState(path, k) {
+    var state = this._state;
+    if (path in state && k in state[path]) {
+      return state[path][k];
+    }
+    return "";
+  },
+
+  /**
+   * Set the value corresponding to a given key for the given path for SJS state
+   * preservation across requests.
+   *
+   * @param path : string
+   *   the path from which the given state is to be retrieved
+   * @param k : string
+   *   the key whose corresponding value is to be set
+   * @param v : string
+   *   the value to be set
+   */
+  _setState(path, k, v) {
+    if (typeof v !== "string") {
+      throw new Error("non-string value passed");
+    }
+    var state = this._state;
+    if (!(path in state)) {
+      state[path] = {};
+    }
+    state[path][k] = v;
+  },
+
+  /**
+   * Get the value corresponding to a given key for SJS state preservation
+   * across requests.
+   *
+   * @param k : string
+   *   the key whose corresponding value is to be returned
+   * @returns string
+   *   the corresponding value, which is initially the empty string
+   */
+  _getSharedState(k) {
+    var state = this._sharedState;
+    if (k in state) {
+      return state[k];
+    }
+    return "";
+  },
+
+  /**
+   * Set the value corresponding to a given key for SJS state preservation
+   * across requests.
+   *
+   * @param k : string
+   *   the key whose corresponding value is to be set
+   * @param v : string
+   *   the value to be set
+   */
+  _setSharedState(k, v) {
+    if (typeof v !== "string") {
+      throw new Error("non-string value passed");
+    }
+    this._sharedState[k] = v;
+  },
+
+  /**
+   * Returns the object associated with the given key in the server for SJS
+   * state preservation across requests.
+   *
+   * @param k : string
+   *  the key whose corresponding object is to be returned
+   * @returns nsISupports
+   *  the corresponding object, or null if none was present
+   */
+  _getObjectState(k) {
+    if (typeof k !== "string") {
+      throw new Error("non-string key passed");
+    }
+    return this._objectState[k] || null;
+  },
+
+  /**
+   * Sets the object associated with the given key in the server for SJS
+   * state preservation across requests.
+   *
+   * @param k : string
+   *  the key whose corresponding object is to be set
+   * @param v : nsISupports
+   *  the object to be associated with the given key; may be null
+   */
+  _setObjectState(k, v) {
+    if (typeof k !== "string") {
+      throw new Error("non-string key passed");
+    }
+    if (typeof v !== "object") {
+      throw new Error("non-object value passed");
+    }
+    if (v && !("QueryInterface" in v)) {
+      throw new Error(
+        "must pass an nsISupports; use wrappedJSObject to ease " +
+          "pain when using the server from JS"
+      );
+    }
+
+    this._objectState[k] = v;
+  },
+
+  /**
+   * Gets a content-type for the given file, first by checking for any custom
+   * MIME-types registered with this handler for the file's extension, second by
+   * asking the global MIME service for a content-type, and finally by failing
+   * over to application/octet-stream.
+   *
+   * @param file : nsIFile
+   *   the nsIFile for which to get a file type
+   * @returns string
+   *   the best content-type which can be determined for the file
+   */
+  _getTypeFromFile(file) {
+    try {
+      var name = file.leafName;
+      var dot = name.lastIndexOf(".");
+      if (dot > 0) {
+        var ext = name.slice(dot + 1);
+        if (ext in this._mimeMappings) {
+          return this._mimeMappings[ext];
+        }
+      }
+      return Cc["@mozilla.org/mime;1"]
+        .getService(Ci.nsIMIMEService)
+        .getTypeFromFile(file);
+    } catch (e) {
+      return "application/octet-stream";
+    }
+  },
+
+  /**
+   * Returns the nsIFile which corresponds to the path, as determined using
+   * all registered path->directory mappings and any paths which are explicitly
+   * overridden.
+   *
+   * @param path : string
+   *   the server path for which a file should be retrieved, e.g. "/foo/bar"
+   * @throws HttpError
+   *   when the correct action is the corresponding HTTP error (i.e., because no
+   *   mapping was found for a directory in path, the referenced file doesn't
+   *   exist, etc.)
+   * @returns nsIFile
+   *   the file to be sent as the response to a request for the path
+   */
+  _getFileForPath(path) {
+    // decode and add underscores as necessary
+    try {
+      path = toInternalPath(path, true);
+    } catch (e) {
+      dumpn("*** toInternalPath threw " + e);
+      throw HTTP_400; // malformed path
+    }
+
+    // next, get the directory which contains this path
+    var pathMap = this._pathDirectoryMap;
+
+    // An example progression of tmp for a path "/foo/bar/baz/" might be:
+    // "foo/bar/baz/", "foo/bar/baz", "foo/bar", "foo", ""
+    var tmp = path.substring(1);
+    while (true) {
+      // do we have a match for current head of the path?
+      var file = pathMap.get(tmp);
+      if (file) {
+        // XXX hack; basically disable showing mapping for /foo/bar/ when the
+        //     requested path was /foo/bar, because relative links on the page
+        //     will all be incorrect -- we really need the ability to easily
+        //     redirect here instead
+        if (
+          tmp == path.substring(1) &&
+          !!tmp.length &&
+          tmp.charAt(tmp.length - 1) != "/"
+        ) {
+          file = null;
+        } else {
+          break;
+        }
+      }
+
+      // if we've finished trying all prefixes, exit
+      if (tmp == "") {
+        break;
+      }
+
+      tmp = tmp.substring(0, tmp.lastIndexOf("/"));
+    }
+
+    // no mapping applies, so 404
+    if (!file) {
+      throw HTTP_404;
+    }
+
+    // last, get the file for the path within the determined directory
+    var parentFolder = file.parent;
+    var dirIsRoot = parentFolder == null;
+
+    // Strategy here is to append components individually, making sure we
+    // never move above the given directory; this allows paths such as
+    // "<file>/foo/../bar" but prevents paths such as "<file>/../base-sibling";
+    // this component-wise approach also means the code works even on platforms
+    // which don't use "/" as the directory separator, such as Windows
+    var leafPath = path.substring(tmp.length + 1);
+    var comps = leafPath.split("/");
+    for (var i = 0, sz = comps.length; i < sz; i++) {
+      var comp = comps[i];
+
+      if (comp == "..") {
+        file = file.parent;
+      } else if (comp == "." || comp == "") {
+        continue;
+      } else {
+        file.append(comp);
+      }
+
+      if (!dirIsRoot && file.equals(parentFolder)) {
+        throw HTTP_403;
+      }
+    }
+
+    return file;
+  },
+
+  /**
+   * Writes the error page for the given HTTP error code over the given
+   * connection.
+   *
+   * @param errorCode : uint
+   *   the HTTP error code to be used
+   * @param connection : Connection
+   *   the connection on which the error occurred
+   */
+  handleError(errorCode, connection) {
+    var response = new Response(connection);
+
+    dumpn("*** error in request: " + errorCode);
+
+    this._handleError(errorCode, new Request(connection.port), response);
+  },
+
+  /**
+   * Handles a request which generates the given error code, using the
+   * user-defined error handler if one has been set, gracefully falling back to
+   * the x00 status code if the code has no handler, and failing to status code
+   * 500 if all else fails.
+   *
+   * @param errorCode : uint
+   *   the HTTP error which is to be returned
+   * @param metadata : Request
+   *   metadata for the request, which will often be incomplete since this is an
+   *   error
+   * @param response : Response
+   *   an uninitialized Response should be initialized when this method
+   *   completes with information which represents the desired error code in the
+   *   ideal case or a fallback code in abnormal circumstances (i.e., 500 is a
+   *   fallback for 505, per HTTP specs)
+   */
+  _handleError(errorCode, metadata, response) {
+    if (!metadata) {
+      throw Components.Exception("", Cr.NS_ERROR_NULL_POINTER);
+    }
+
+    var errorX00 = errorCode - (errorCode % 100);
+
+    try {
+      if (!(errorCode in HTTP_ERROR_CODES)) {
+        dumpn("*** WARNING: requested invalid error: " + errorCode);
+      }
+
+      // RFC 2616 says that we should try to handle an error by its class if we
+      // can't otherwise handle it -- if that fails, we revert to handling it as
+      // a 500 internal server error, and if that fails we throw and shut down
+      // the server
+
+      // actually handle the error
+      try {
+        if (errorCode in this._overrideErrors) {
+          this._overrideErrors[errorCode](metadata, response);
+        } else {
+          this._defaultErrors[errorCode](metadata, response);
+        }
+      } catch (e) {
+        if (response.partiallySent()) {
+          response.abort(e);
+          return;
+        }
+
+        // don't retry the handler that threw
+        if (errorX00 == errorCode) {
+          throw HTTP_500;
+        }
+
+        dumpn(
+          "*** error in handling for error code " +
+            errorCode +
+            ", " +
+            "falling back to " +
+            errorX00 +
+            "..."
+        );
+        response = new Response(response._connection);
+        if (errorX00 in this._overrideErrors) {
+          this._overrideErrors[errorX00](metadata, response);
+        } else if (errorX00 in this._defaultErrors) {
+          this._defaultErrors[errorX00](metadata, response);
+        } else {
+          throw HTTP_500;
+        }
+      }
+    } catch (e) {
+      if (response.partiallySent()) {
+        response.abort();
+        return;
+      }
+
+      // we've tried everything possible for a meaningful error -- now try 500
+      dumpn(
+        "*** error in handling for error code " +
+          errorX00 +
+          ", falling " +
+          "back to 500..."
+      );
+
+      try {
+        response = new Response(response._connection);
+        if (500 in this._overrideErrors) {
+          this._overrideErrors[500](metadata, response);
+        } else {
+          this._defaultErrors[500](metadata, response);
+        }
+      } catch (e2) {
+        dumpn("*** multiple errors in default error handlers!");
+        dumpn("*** e == " + e + ", e2 == " + e2);
+        response.abort(e2);
+        return;
+      }
+    }
+
+    response.complete();
+  },
+
+  // FIELDS
+
+  /**
+   * This object contains the default handlers for the various HTTP error codes.
+   */
+  _defaultErrors: {
+    400(metadata, response) {
+      // none of the data in metadata is reliable, so hard-code everything here
+      response.setStatusLine("1.1", 400, "Bad Request");
+      response.setHeader("Content-Type", "text/plain;charset=utf-8", false);
+
+      var body = "Bad request\n";
+      response.bodyOutputStream.write(body, body.length);
+    },
+    403(metadata, response) {
+      response.setStatusLine(metadata.httpVersion, 403, "Forbidden");
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                    <head><title>403 Forbidden</title></head>\
+                    <body>\
+                      <h1>403 Forbidden</h1>\
+                    </body>\
+                  </html>";
+      response.bodyOutputStream.write(body, body.length);
+    },
+    404(metadata, response) {
+      response.setStatusLine(metadata.httpVersion, 404, "Not Found");
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                    <head><title>404 Not Found</title></head>\
+                    <body>\
+                      <h1>404 Not Found</h1>\
+                      <p>\
+                        <span style='font-family: monospace;'>" +
+        htmlEscape(metadata.path) +
+        "</span> was not found.\
+                      </p>\
+                    </body>\
+                  </html>";
+      response.bodyOutputStream.write(body, body.length);
+    },
+    416(metadata, response) {
+      response.setStatusLine(
+        metadata.httpVersion,
+        416,
+        "Requested Range Not Satisfiable"
+      );
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                   <head>\
+                    <title>416 Requested Range Not Satisfiable</title></head>\
+                    <body>\
+                     <h1>416 Requested Range Not Satisfiable</h1>\
+                     <p>The byte range was not valid for the\
+                        requested resource.\
+                     </p>\
+                    </body>\
+                  </html>";
+      response.bodyOutputStream.write(body, body.length);
+    },
+    500(metadata, response) {
+      response.setStatusLine(
+        metadata.httpVersion,
+        500,
+        "Internal Server Error"
+      );
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                    <head><title>500 Internal Server Error</title></head>\
+                    <body>\
+                      <h1>500 Internal Server Error</h1>\
+                      <p>Something's broken in this server and\
+                        needs to be fixed.</p>\
+                    </body>\
+                  </html>";
+      response.bodyOutputStream.write(body, body.length);
+    },
+    501(metadata, response) {
+      response.setStatusLine(metadata.httpVersion, 501, "Not Implemented");
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                    <head><title>501 Not Implemented</title></head>\
+                    <body>\
+                      <h1>501 Not Implemented</h1>\
+                      <p>This server is not (yet) Apache.</p>\
+                    </body>\
+                  </html>";
+      response.bodyOutputStream.write(body, body.length);
+    },
+    505(metadata, response) {
+      response.setStatusLine("1.1", 505, "HTTP Version Not Supported");
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                    <head><title>505 HTTP Version Not Supported</title></head>\
+                    <body>\
+                      <h1>505 HTTP Version Not Supported</h1>\
+                      <p>This server only supports HTTP/1.0 and HTTP/1.1\
+                        connections.</p>\
+                    </body>\
+                  </html>";
+      response.bodyOutputStream.write(body, body.length);
+    },
+  },
+
+  /**
+   * Contains handlers for the default set of URIs contained in this server.
+   */
+  _defaultPaths: {
+    "/": function (metadata, response) {
+      response.setStatusLine(metadata.httpVersion, 200, "OK");
+      response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+
+      var body =
+        "<html>\
+                    <head><title>httpd.js</title></head>\
+                    <body>\
+                      <h1>httpd.js</h1>\
+                      <p>If you're seeing this page, httpd.js is up and\
+                        serving requests!  Now set a base path and serve some\
+                        files!</p>\
+                    </body>\
+                  </html>";
+
+      response.bodyOutputStream.write(body, body.length);
+    },
+
+    "/trace": function (metadata, response) {
+      response.setStatusLine(metadata.httpVersion, 200, "OK");
+      response.setHeader("Content-Type", "text/plain;charset=utf-8", false);
+
+      var body =
+        "Request-URI: " +
+        metadata.scheme +
+        "://" +
+        metadata.host +
+        ":" +
+        metadata.port +
+        metadata.path +
+        "\n\n";
+      body += "Request (semantically equivalent, slightly reformatted):\n\n";
+      body += metadata.method + " " + metadata.path;
+
+      if (metadata.queryString) {
+        body += "?" + metadata.queryString;
+      }
+
+      body += " HTTP/" + metadata.httpVersion + "\r\n";
+
+      var headEnum = metadata.headers;
+      while (headEnum.hasMoreElements()) {
+        var fieldName = headEnum
+          .getNext()
+          .QueryInterface(Ci.nsISupportsString).data;
+        body += fieldName + ": " + metadata.getHeader(fieldName) + "\r\n";
+      }
+
+      response.bodyOutputStream.write(body, body.length);
+    },
+  },
+};
+
+/**
+ * Maps absolute paths to files on the local file system (as nsILocalFiles).
+ */
+function FileMap() {
+  /** Hash which will map paths to nsILocalFiles. */
+  this._map = {};
+}
+FileMap.prototype = {
+  // PUBLIC API
+
+  /**
+   * Maps key to a clone of the nsIFile value if value is non-null;
+   * otherwise, removes any extant mapping for key.
+   *
+   * @param key : string
+   *   string to which a clone of value is mapped
+   * @param value : nsIFile
+   *   the file to map to key, or null to remove a mapping
+   */
+  put(key, value) {
+    if (value) {
+      this._map[key] = value.clone();
+    } else {
+      delete this._map[key];
+    }
+  },
+
+  /**
+   * Returns a clone of the nsIFile mapped to key, or null if no such
+   * mapping exists.
+   *
+   * @param key : string
+   *   key to which the returned file maps
+   * @returns nsIFile
+   *   a clone of the mapped file, or null if no mapping exists
+   */
+  get(key) {
+    var val = this._map[key];
+    return val ? val.clone() : null;
+  },
+};
+
+// Response CONSTANTS
+
+// token       = *<any CHAR except CTLs or separators>
+// CHAR        = <any US-ASCII character (0-127)>
+// CTL         = <any US-ASCII control character (0-31) and DEL (127)>
+// separators  = "(" | ")" | "<" | ">" | "@"
+//             | "," | ";" | ":" | "\" | <">
+//             | "/" | "[" | "]" | "?" | "="
+//             | "{" | "}" | SP  | HT
+const IS_TOKEN_ARRAY = [
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0, //   0
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0, //   8
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0, //  16
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0, //  24
+
+  0,
+  1,
+  0,
+  1,
+  1,
+  1,
+  1,
+  1, //  32
+  0,
+  0,
+  1,
+  1,
+  0,
+  1,
+  1,
+  0, //  40
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, //  48
+  1,
+  1,
+  0,
+  0,
+  0,
+  0,
+  0,
+  0, //  56
+
+  0,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, //  64
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, //  72
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, //  80
+  1,
+  1,
+  1,
+  0,
+  0,
+  0,
+  1,
+  1, //  88
+
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, //  96
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, // 104
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1,
+  1, // 112
+  1,
+  1,
+  1,
+  0,
+  1,
+  0,
+  1,
+]; // 120
+
+/**
+ * Determines whether the given character code is a CTL.
+ *
+ * @param code : uint
+ *   the character code
+ * @returns boolean
+ *   true if code is a CTL, false otherwise
+ */
+function isCTL(code) {
+  return (code >= 0 && code <= 31) || code == 127;
+}
+
+/**
+ * Represents a response to an HTTP request, encapsulating all details of that
+ * response.  This includes all headers, the HTTP version, status code and
+ * explanation, and the entity itself.
+ *
+ * @param connection : Connection
+ *   the connection over which this response is to be written
+ */
+function Response(connection) {
+  /** The connection over which this response will be written. */
+  this._connection = connection;
+
+  /**
+   * The HTTP version of this response; defaults to 1.1 if not set by the
+   * handler.
+   */
+  this._httpVersion = nsHttpVersion.HTTP_1_1;
+
+  /**
+   * The HTTP code of this response; defaults to 200.
+   */
+  this._httpCode = 200;
+
+  /**
+   * The description of the HTTP code in this response; defaults to "OK".
+   */
+  this._httpDescription = "OK";
+
+  /**
+   * An nsIHttpHeaders object in which the headers in this response should be
+   * stored.  This property is null after the status line and headers have been
+   * written to the network, and it may be modified up until it is cleared,
+   * except if this._finished is set first (in which case headers are written
+   * asynchronously in response to a finish() call not preceded by
+   * flushHeaders()).
+   */
+  this._headers = new nsHttpHeaders();
+
+  /**
+   * Informational response:
+   * For example 103 Early Hint
+   **/
+  this._informationalResponseHttpVersion = nsHttpVersion.HTTP_1_1;
+  this._informationalResponseHttpCode = 0;
+  this._informationalResponseHttpDescription = "";
+  this._informationalResponseHeaders = new nsHttpHeaders();
+  this._informationalResponseSet = false;
+
+  /**
+   * Set to true when this response is ended (completely constructed if possible
+   * and the connection closed); further actions on this will then fail.
+   */
+  this._ended = false;
+
+  /**
+   * A stream used to hold data written to the body of this response.
+   */
+  this._bodyOutputStream = null;
+
+  /**
+   * A stream containing all data that has been written to the body of this
+   * response so far.  (Async handlers make the data contained in this
+   * unreliable as a way of determining content length in general, but auxiliary
+   * saved information can sometimes be used to guarantee reliability.)
+   */
+  this._bodyInputStream = null;
+
+  /**
+   * A stream copier which copies data to the network.  It is initially null
+   * until replaced with a copier for response headers; when headers have been
+   * fully sent it is replaced with a copier for the response body, remaining
+   * so for the duration of response processing.
+   */
+  this._asyncCopier = null;
+
+  /**
+   * True if this response has been designated as being processed
+   * asynchronously rather than for the duration of a single call to
+   * nsIHttpRequestHandler.handle.
+   */
+  this._processAsync = false;
+
+  /**
+   * True iff finish() has been called on this, signaling that no more changes
+   * to this may be made.
+   */
+  this._finished = false;
+
+  /**
+   * True iff powerSeized() has been called on this, signaling that this
+   * response is to be handled manually by the response handler (which may then
+   * send arbitrary data in response, even non-HTTP responses).
+   */
+  this._powerSeized = false;
+}
+Response.prototype = {
+  // PUBLIC CONSTRUCTION API
+
+  //
+  // see nsIHttpResponse.bodyOutputStream
+  //
+  get bodyOutputStream() {
+    if (this._finished) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+
+    if (!this._bodyOutputStream) {
+      var pipe = new Pipe(
+        true,
+        false,
+        Response.SEGMENT_SIZE,
+        PR_UINT32_MAX,
+        null
+      );
+      this._bodyOutputStream = pipe.outputStream;
+      this._bodyInputStream = pipe.inputStream;
+      if (this._processAsync || this._powerSeized) {
+        this._startAsyncProcessor();
+      }
+    }
+
+    return this._bodyOutputStream;
+  },
+
+  //
+  // see nsIHttpResponse.write
+  //
+  write(data) {
+    if (this._finished) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+
+    var dataAsString = String(data);
+    this.bodyOutputStream.write(dataAsString, dataAsString.length);
+  },
+
+  //
+  // see nsIHttpResponse.setStatusLine
+  //
+  setStatusLineInternal(httpVersion, code, description, informationalResponse) {
+    if (this._finished || this._powerSeized) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+
+    if (!informationalResponse) {
+      if (!this._headers) {
+        throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+      }
+    } else if (!this._informationalResponseHeaders) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    this._ensureAlive();
+
+    if (!(code >= 0 && code < 1000)) {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    try {
+      var httpVer;
+      // avoid version construction for the most common cases
+      if (!httpVersion || httpVersion == "1.1") {
+        httpVer = nsHttpVersion.HTTP_1_1;
+      } else if (httpVersion == "1.0") {
+        httpVer = nsHttpVersion.HTTP_1_0;
+      } else {
+        httpVer = new nsHttpVersion(httpVersion);
+      }
+    } catch (e) {
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    // Reason-Phrase = *<TEXT, excluding CR, LF>
+    // TEXT          = <any OCTET except CTLs, but including LWS>
+    //
+    // XXX this ends up disallowing octets which aren't Unicode, I think -- not
+    //     much to do if description is IDL'd as string
+    if (!description) {
+      description = "";
+    }
+    for (var i = 0; i < description.length; i++) {
+      if (isCTL(description.charCodeAt(i)) && description.charAt(i) != "\t") {
+        throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+      }
+    }
+
+    // set the values only after validation to preserve atomicity
+    if (!informationalResponse) {
+      this._httpDescription = description;
+      this._httpCode = code;
+      this._httpVersion = httpVer;
+    } else {
+      this._informationalResponseSet = true;
+      this._informationalResponseHttpDescription = description;
+      this._informationalResponseHttpCode = code;
+      this._informationalResponseHttpVersion = httpVer;
+    }
+  },
+
+  //
+  // see nsIHttpResponse.setStatusLine
+  //
+  setStatusLine(httpVersion, code, description) {
+    this.setStatusLineInternal(httpVersion, code, description, false);
+  },
+
+  setInformationalResponseStatusLine(httpVersion, code, description) {
+    this.setStatusLineInternal(httpVersion, code, description, true);
+  },
+
+  //
+  // see nsIHttpResponse.setHeader
+  //
+  setHeader(name, value, merge) {
+    if (!this._headers || this._finished || this._powerSeized) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    this._ensureAlive();
+
+    this._headers.setHeader(name, value, merge);
+  },
+
+  setInformationalResponseHeader(name, value, merge) {
+    if (
+      !this._informationalResponseHeaders ||
+      this._finished ||
+      this._powerSeized
+    ) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    this._ensureAlive();
+
+    this._informationalResponseHeaders.setHeader(name, value, merge);
+  },
+
+  setHeaderNoCheck(name, value) {
+    if (!this._headers || this._finished || this._powerSeized) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    this._ensureAlive();
+
+    this._headers.setHeaderNoCheck(name, value);
+  },
+
+  setInformationalHeaderNoCheck(name, value) {
+    if (!this._headers || this._finished || this._powerSeized) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    this._ensureAlive();
+
+    this._informationalResponseHeaders.setHeaderNoCheck(name, value);
+  },
+
+  //
+  // see nsIHttpResponse.processAsync
+  //
+  processAsync() {
+    if (this._finished) {
+      throw Components.Exception("", Cr.NS_ERROR_UNEXPECTED);
+    }
+    if (this._powerSeized) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    if (this._processAsync) {
+      return;
+    }
+    this._ensureAlive();
+
+    dumpn("*** processing connection " + this._connection.number + " async");
+    this._processAsync = true;
+
+    /*
+     * Either the bodyOutputStream getter or this method is responsible for
+     * starting the asynchronous processor and catching writes of data to the
+     * response body of async responses as they happen, for the purpose of
+     * forwarding those writes to the actual connection's output stream.
+     * If bodyOutputStream is accessed first, calling this method will create
+     * the processor (when it first is clear that body data is to be written
+     * immediately, not buffered).  If this method is called first, accessing
+     * bodyOutputStream will create the processor.  If only this method is
+     * called, we'll write nothing, neither headers nor the nonexistent body,
+     * until finish() is called.  Since that delay is easily avoided by simply
+     * getting bodyOutputStream or calling write(""), we don't worry about it.
+     */
+    if (this._bodyOutputStream && !this._asyncCopier) {
+      this._startAsyncProcessor();
+    }
+  },
+
+  //
+  // see nsIHttpResponse.seizePower
+  //
+  seizePower() {
+    if (this._processAsync) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+    if (this._finished) {
+      throw Components.Exception("", Cr.NS_ERROR_UNEXPECTED);
+    }
+    if (this._powerSeized) {
+      return;
+    }
+    this._ensureAlive();
+
+    dumpn(
+      "*** forcefully seizing power over connection " +
+        this._connection.number +
+        "..."
+    );
+
+    // Purge any already-written data without sending it.  We could as easily
+    // swap out the streams entirely, but that makes it possible to acquire and
+    // unknowingly use a stale reference, so we require there only be one of
+    // each stream ever for any response to avoid this complication.
+    if (this._asyncCopier) {
+      this._asyncCopier.cancel(Cr.NS_BINDING_ABORTED);
+    }
+    this._asyncCopier = null;
+    if (this._bodyOutputStream) {
+      var input = new BinaryInputStream(this._bodyInputStream);
+      var avail;
+      while ((avail = input.available()) > 0) {
+        input.readByteArray(avail);
+      }
+    }
+
+    this._powerSeized = true;
+    if (this._bodyOutputStream) {
+      this._startAsyncProcessor();
+    }
+  },
+
+  //
+  // see nsIHttpResponse.finish
+  //
+  finish() {
+    if (!this._processAsync && !this._powerSeized) {
+      throw Components.Exception("", Cr.NS_ERROR_UNEXPECTED);
+    }
+    if (this._finished) {
+      return;
+    }
+
+    dumpn("*** finishing connection " + this._connection.number);
+    this._startAsyncProcessor(); // in case bodyOutputStream was never accessed
+    if (this._bodyOutputStream) {
+      this._bodyOutputStream.close();
+    }
+    this._finished = true;
+  },
+
+  // NSISUPPORTS
+
+  //
+  // see nsISupports.QueryInterface
+  //
+  QueryInterface: ChromeUtils.generateQI(["nsIHttpResponse"]),
+
+  // POST-CONSTRUCTION API (not exposed externally)
+
+  /**
+   * The HTTP version number of this, as a string (e.g. "1.1").
+   */
+  get httpVersion() {
+    this._ensureAlive();
+    return this._httpVersion.toString();
+  },
+
+  /**
+   * The HTTP status code of this response, as a string of three characters per
+   * RFC 2616.
+   */
+  get httpCode() {
+    this._ensureAlive();
+
+    var codeString =
+      (this._httpCode < 10 ? "0" : "") +
+      (this._httpCode < 100 ? "0" : "") +
+      this._httpCode;
+    return codeString;
+  },
+
+  /**
+   * The description of the HTTP status code of this response, or "" if none is
+   * set.
+   */
+  get httpDescription() {
+    this._ensureAlive();
+
+    return this._httpDescription;
+  },
+
+  /**
+   * The headers in this response, as an nsHttpHeaders object.
+   */
+  get headers() {
+    this._ensureAlive();
+
+    return this._headers;
+  },
+
+  //
+  // see nsHttpHeaders.getHeader
+  //
+  getHeader(name) {
+    this._ensureAlive();
+
+    return this._headers.getHeader(name);
+  },
+
+  /**
+   * Determines whether this response may be abandoned in favor of a newly
+   * constructed response.  A response may be abandoned only if it is not being
+   * sent asynchronously and if raw control over it has not been taken from the
+   * server.
+   *
+   * @returns boolean
+   *   true iff no data has been written to the network
+   */
+  partiallySent() {
+    dumpn("*** partiallySent()");
+    return this._processAsync || this._powerSeized;
+  },
+
+  /**
+   * If necessary, kicks off the remaining request processing needed to be done
+   * after a request handler performs its initial work upon this response.
+   */
+  complete() {
+    dumpn("*** complete()");
+    if (this._processAsync || this._powerSeized) {
+      NS_ASSERT(
+        this._processAsync ^ this._powerSeized,
+        "can't both send async and relinquish power"
+      );
+      return;
+    }
+
+    NS_ASSERT(!this.partiallySent(), "completing a partially-sent response?");
+
+    this._startAsyncProcessor();
+
+    // Now make sure we finish processing this request!
+    if (this._bodyOutputStream) {
+      this._bodyOutputStream.close();
+    }
+  },
+
+  /**
+   * Abruptly ends processing of this response, usually due to an error in an
+   * incoming request but potentially due to a bad error handler.  Since we
+   * cannot handle the error in the usual way (giving an HTTP error page in
+   * response) because data may already have been sent (or because the response
+   * might be expected to have been generated asynchronously or completely from
+   * scratch by the handler), we stop processing this response and abruptly
+   * close the connection.
+   *
+   * @param e : Error
+   *   the exception which precipitated this abort, or null if no such exception
+   *   was generated
+   * @param truncateConnection : Boolean
+   *   ensures that we truncate the connection using an RST packet, so the
+   *   client testing code is aware that an error occurred, otherwise it may
+   *   consider the response as valid.
+   */
+  abort(e, truncateConnection = false) {
+    dumpn("*** abort(<" + e + ">)");
+
+    if (truncateConnection) {
+      dumpn("*** truncate connection");
+      this._connection.transport.setLinger(true, 0);
+    }
+
+    // This response will be ended by the processor if one was created.
+    var copier = this._asyncCopier;
+    if (copier) {
+      // We dispatch asynchronously here so that any pending writes of data to
+      // the connection will be deterministically written.  This makes it easier
+      // to specify exact behavior, and it makes observable behavior more
+      // predictable for clients.  Note that the correctness of this depends on
+      // callbacks in response to _waitToReadData in WriteThroughCopier
+      // happening asynchronously with respect to the actual writing of data to
+      // bodyOutputStream, as they currently do; if they happened synchronously,
+      // an event which ran before this one could write more data to the
+      // response body before we get around to canceling the copier.  We have
+      // tests for this in test_seizepower.js, however, and I can't think of a
+      // way to handle both cases without removing bodyOutputStream access and
+      // moving its effective write(data, length) method onto Response, which
+      // would be slower and require more code than this anyway.
+      Services.tm.currentThread.dispatch(
+        {
+          run() {
+            dumpn("*** canceling copy asynchronously...");
+            copier.cancel(Cr.NS_ERROR_UNEXPECTED);
+          },
+        },
+        Ci.nsIThread.DISPATCH_NORMAL
+      );
+    } else {
+      this.end();
+    }
+  },
+
+  /**
+   * Closes this response's network connection, marks the response as finished,
+   * and notifies the server handler that the request is done being processed.
+   */
+  end() {
+    NS_ASSERT(!this._ended, "ending this response twice?!?!");
+
+    this._connection.close();
+    if (this._bodyOutputStream) {
+      this._bodyOutputStream.close();
+    }
+
+    this._finished = true;
+    this._ended = true;
+  },
+
+  // PRIVATE IMPLEMENTATION
+
+  /**
+   * Sends the status line and headers of this response if they haven't been
+   * sent and initiates the process of copying data written to this response's
+   * body to the network.
+   */
+  _startAsyncProcessor() {
+    dumpn("*** _startAsyncProcessor()");
+
+    // Handle cases where we're being called a second time.  The former case
+    // happens when this is triggered both by complete() and by processAsync(),
+    // while the latter happens when processAsync() in conjunction with sent
+    // data causes abort() to be called.
+    if (this._asyncCopier || this._ended) {
+      dumpn("*** ignoring second call to _startAsyncProcessor");
+      return;
+    }
+
+    // Send headers if they haven't been sent already and should be sent, then
+    // asynchronously continue to send the body.
+    if (this._headers && !this._powerSeized) {
+      this._sendHeaders();
+      return;
+    }
+
+    this._headers = null;
+    this._sendBody();
+  },
+
+  /**
+   * Signals that all modifications to the response status line and headers are
+   * complete and then sends that data over the network to the client.  Once
+   * this method completes, a different response to the request that resulted
+   * in this response cannot be sent -- the only possible action in case of
+   * error is to abort the response and close the connection.
+   */
+  _sendHeaders() {
+    dumpn("*** _sendHeaders()");
+
+    NS_ASSERT(this._headers);
+    NS_ASSERT(this._informationalResponseHeaders);
+    NS_ASSERT(!this._powerSeized);
+
+    var preambleData = [];
+
+    // Informational response, e.g. 103
+    if (this._informationalResponseSet) {
+      // request-line
+      let statusLine =
+        "HTTP/" +
+        this._informationalResponseHttpVersion +
+        " " +
+        this._informationalResponseHttpCode +
+        " " +
+        this._informationalResponseHttpDescription +
+        "\r\n";
+      preambleData.push(statusLine);
+
+      // headers
+      let headEnum = this._informationalResponseHeaders.enumerator;
+      while (headEnum.hasMoreElements()) {
+        let fieldName = headEnum
+          .getNext()
+          .QueryInterface(Ci.nsISupportsString).data;
+        let values =
+          this._informationalResponseHeaders.getHeaderValues(fieldName);
+        for (let i = 0, sz = values.length; i < sz; i++) {
+          preambleData.push(fieldName + ": " + values[i] + "\r\n");
+        }
+      }
+      // end request-line/headers
+      preambleData.push("\r\n");
+    }
+
+    // request-line
+    var statusLine =
+      "HTTP/" +
+      this.httpVersion +
+      " " +
+      this.httpCode +
+      " " +
+      this.httpDescription +
+      "\r\n";
+
+    // header post-processing
+
+    var headers = this._headers;
+    headers.setHeader("Connection", "close", false);
+    headers.setHeader("Server", "httpd.js", false);
+    if (!headers.hasHeader("Date")) {
+      headers.setHeader("Date", toDateString(Date.now()), false);
+    }
+
+    // Any response not being processed asynchronously must have an associated
+    // Content-Length header for reasons of backwards compatibility with the
+    // initial server, which fully buffered every response before sending it.
+    // Beyond that, however, it's good to do this anyway because otherwise it's
+    // impossible to test behaviors that depend on the presence or absence of a
+    // Content-Length header.
+    if (!this._processAsync) {
+      dumpn("*** non-async response, set Content-Length");
+
+      var bodyStream = this._bodyInputStream;
+      var avail = bodyStream ? bodyStream.available() : 0;
+
+      // XXX assumes stream will always report the full amount of data available
+      headers.setHeader("Content-Length", "" + avail, false);
+    }
+
+    // construct and send response
+    dumpn("*** header post-processing completed, sending response head...");
+
+    // request-line
+    preambleData.push(statusLine);
+
+    // headers
+    var headEnum = headers.enumerator;
+    while (headEnum.hasMoreElements()) {
+      var fieldName = headEnum
+        .getNext()
+        .QueryInterface(Ci.nsISupportsString).data;
+      var values = headers.getHeaderValues(fieldName);
+      for (var i = 0, sz = values.length; i < sz; i++) {
+        preambleData.push(fieldName + ": " + values[i] + "\r\n");
+      }
+    }
+
+    // end request-line/headers
+    preambleData.push("\r\n");
+
+    var preamble = preambleData.join("");
+
+    var responseHeadPipe = new Pipe(true, false, 0, PR_UINT32_MAX, null);
+    responseHeadPipe.outputStream.write(preamble, preamble.length);
+
+    var response = this;
+    var copyObserver = {
+      onStartRequest(request) {
+        dumpn("*** preamble copying started");
+      },
+
+      onStopRequest(request, statusCode) {
+        dumpn(
+          "*** preamble copying complete " +
+            "[status=0x" +
+            statusCode.toString(16) +
+            "]"
+        );
+
+        if (!Components.isSuccessCode(statusCode)) {
+          dumpn(
+            "!!! header copying problems: non-success statusCode, " +
+              "ending response"
+          );
+
+          response.end();
+        } else {
+          response._sendBody();
+        }
+      },
+
+      QueryInterface: ChromeUtils.generateQI(["nsIRequestObserver"]),
+    };
+
+    this._asyncCopier = new WriteThroughCopier(
+      responseHeadPipe.inputStream,
+      this._connection.output,
+      copyObserver,
+      null
+    );
+
+    responseHeadPipe.outputStream.close();
+
+    // Forbid setting any more headers or modifying the request line.
+    this._headers = null;
+  },
+
+  /**
+   * Asynchronously writes the body of the response (or the entire response, if
+   * seizePower() has been called) to the network.
+   */
+  _sendBody() {
+    dumpn("*** _sendBody");
+
+    NS_ASSERT(!this._headers, "still have headers around but sending body?");
+
+    // If no body data was written, we're done
+    if (!this._bodyInputStream) {
+      dumpn("*** empty body, response finished");
+      this.end();
+      return;
+    }
+
+    var response = this;
+    var copyObserver = {
+      onStartRequest(request) {
+        dumpn("*** onStartRequest");
+      },
+
+      onStopRequest(request, statusCode) {
+        dumpn("*** onStopRequest [status=0x" + statusCode.toString(16) + "]");
+
+        if (statusCode === Cr.NS_BINDING_ABORTED) {
+          dumpn("*** terminating copy observer without ending the response");
+        } else {
+          if (!Components.isSuccessCode(statusCode)) {
+            dumpn("*** WARNING: non-success statusCode in onStopRequest");
+          }
+
+          response.end();
+        }
+      },
+
+      QueryInterface: ChromeUtils.generateQI(["nsIRequestObserver"]),
+    };
+
+    dumpn("*** starting async copier of body data...");
+    this._asyncCopier = new WriteThroughCopier(
+      this._bodyInputStream,
+      this._connection.output,
+      copyObserver,
+      null
+    );
+  },
+
+  /** Ensures that this hasn't been ended. */
+  _ensureAlive() {
+    NS_ASSERT(!this._ended, "not handling response lifetime correctly");
+  },
+};
+
+/**
+ * Size of the segments in the buffer used in storing response data and writing
+ * it to the socket.
+ */
+Response.SEGMENT_SIZE = 8192;
+
+/** Serves double duty in WriteThroughCopier implementation. */
+function notImplemented() {
+  throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+}
+
+/** Returns true iff the given exception represents stream closure. */
+function streamClosed(e) {
+  return (
+    e === Cr.NS_BASE_STREAM_CLOSED ||
+    (typeof e === "object" && e.result === Cr.NS_BASE_STREAM_CLOSED)
+  );
+}
+
+/** Returns true iff the given exception represents a blocked stream. */
+function wouldBlock(e) {
+  return (
+    e === Cr.NS_BASE_STREAM_WOULD_BLOCK ||
+    (typeof e === "object" && e.result === Cr.NS_BASE_STREAM_WOULD_BLOCK)
+  );
+}
+
+/**
+ * Copies data from source to sink as it becomes available, when that data can
+ * be written to sink without blocking.
+ *
+ * @param source : nsIAsyncInputStream
+ *   the stream from which data is to be read
+ * @param sink : nsIAsyncOutputStream
+ *   the stream to which data is to be copied
+ * @param observer : nsIRequestObserver
+ *   an observer which will be notified when the copy starts and finishes
+ * @param context : nsISupports
+ *   context passed to observer when notified of start/stop
+ * @throws NS_ERROR_NULL_POINTER
+ *   if source, sink, or observer are null
+ */
+export function WriteThroughCopier(source, sink, observer, context) {
+  if (!source || !sink || !observer) {
+    throw Components.Exception("", Cr.NS_ERROR_NULL_POINTER);
+  }
+
+  /** Stream from which data is being read. */
+  this._source = source;
+
+  /** Stream to which data is being written. */
+  this._sink = sink;
+
+  /** Observer watching this copy. */
+  this._observer = observer;
+
+  /** Context for the observer watching this. */
+  this._context = context;
+
+  /**
+   * True iff this is currently being canceled (cancel has been called, the
+   * callback may not yet have been made).
+   */
+  this._canceled = false;
+
+  /**
+   * False until all data has been read from input and written to output, at
+   * which point this copy is completed and cancel() is asynchronously called.
+   */
+  this._completed = false;
+
+  /** Required by nsIRequest, meaningless. */
+  this.loadFlags = 0;
+  /** Required by nsIRequest, meaningless. */
+  this.loadGroup = null;
+  /** Required by nsIRequest, meaningless. */
+  this.name = "response-body-copy";
+
+  /** Status of this request. */
+  this.status = Cr.NS_OK;
+
+  /** Arrays of byte strings waiting to be written to output. */
+  this._pendingData = [];
+
+  // start copying
+  try {
+    observer.onStartRequest(this);
+    this._waitToReadData();
+    this._waitForSinkClosure();
+  } catch (e) {
+    dumpn(
+      "!!! error starting copy: " +
+        e +
+        ("lineNumber" in e ? ", line " + e.lineNumber : "")
+    );
+    dumpn(e.stack);
+    this.cancel(Cr.NS_ERROR_UNEXPECTED);
+  }
+}
+WriteThroughCopier.prototype = {
+  /* nsISupports implementation */
+
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIInputStreamCallback",
+    "nsIOutputStreamCallback",
+    "nsIRequest",
+  ]),
+
+  // NSIINPUTSTREAMCALLBACK
+
+  /**
+   * Receives a more-data-in-input notification and writes the corresponding
+   * data to the output.
+   *
+   * @param input : nsIAsyncInputStream
+   *   the input stream on whose data we have been waiting
+   */
+  onInputStreamReady(input) {
+    if (this._source === null) {
+      return;
+    }
+
+    dumpn("*** onInputStreamReady");
+
+    //
+    // Ordinarily we'll read a non-zero amount of data from input, queue it up
+    // to be written and then wait for further callbacks.  The complications in
+    // this method are the cases where we deviate from that behavior when errors
+    // occur or when copying is drawing to a finish.
+    //
+    // The edge cases when reading data are:
+    //
+    //   Zero data is read
+    //     If zero data was read, we're at the end of available data, so we can
+    //     should stop reading and move on to writing out what we have (or, if
+    //     we've already done that, onto notifying of completion).
+    //   A stream-closed exception is thrown
+    //     This is effectively a less kind version of zero data being read; the
+    //     only difference is that we notify of completion with that result
+    //     rather than with NS_OK.
+    //   Some other exception is thrown
+    //     This is the least kind result.  We don't know what happened, so we
+    //     act as though the stream closed except that we notify of completion
+    //     with the result NS_ERROR_UNEXPECTED.
+    //
+
+    var bytesWanted = 0,
+      bytesConsumed = -1;
+    try {
+      input = new BinaryInputStream(input);
+
+      bytesWanted = Math.min(input.available(), Response.SEGMENT_SIZE);
+      dumpn("*** input wanted: " + bytesWanted);
+
+      if (bytesWanted > 0) {
+        var data = input.readByteArray(bytesWanted);
+        bytesConsumed = data.length;
+        this._pendingData.push(String.fromCharCode.apply(String, data));
+      }
+
+      dumpn("*** " + bytesConsumed + " bytes read");
+
+      // Handle the zero-data edge case in the same place as all other edge
+      // cases are handled.
+      if (bytesWanted === 0) {
+        throw Components.Exception("", Cr.NS_BASE_STREAM_CLOSED);
+      }
+    } catch (e) {
+      let rv;
+      if (streamClosed(e)) {
+        dumpn("*** input stream closed");
+        rv = bytesWanted === 0 ? Cr.NS_OK : Cr.NS_ERROR_UNEXPECTED;
+      } else {
+        dumpn("!!! unexpected error reading from input, canceling: " + e);
+        rv = Cr.NS_ERROR_UNEXPECTED;
+      }
+
+      this._doneReadingSource(rv);
+      return;
+    }
+
+    var pendingData = this._pendingData;
+
+    NS_ASSERT(bytesConsumed > 0);
+    NS_ASSERT(!!pendingData.length, "no pending data somehow?");
+    NS_ASSERT(
+      !!pendingData[pendingData.length - 1].length,
+      "buffered zero bytes of data?"
+    );
+
+    NS_ASSERT(this._source !== null);
+
+    // Reading has gone great, and we've gotten data to write now.  What if we
+    // don't have a place to write that data, because output went away just
+    // before this read?  Drop everything on the floor, including new data, and
+    // cancel at this point.
+    if (this._sink === null) {
+      pendingData.length = 0;
+      this._doneReadingSource(Cr.NS_ERROR_UNEXPECTED);
+      return;
+    }
+
+    // Okay, we've read the data, and we know we have a place to write it.  We
+    // need to queue up the data to be written, but *only* if none is queued
+    // already -- if data's already queued, the code that actually writes the
+    // data will make sure to wait on unconsumed pending data.
+    try {
+      if (pendingData.length === 1) {
+        this._waitToWriteData();
+      }
+    } catch (e) {
+      dumpn(
+        "!!! error waiting to write data just read, swallowing and " +
+          "writing only what we already have: " +
+          e
+      );
+      this._doneWritingToSink(Cr.NS_ERROR_UNEXPECTED);
+      return;
+    }
+
+    // Whee!  We successfully read some data, and it's successfully queued up to
+    // be written.  All that remains now is to wait for more data to read.
+    try {
+      this._waitToReadData();
+    } catch (e) {
+      dumpn("!!! error waiting to read more data: " + e);
+      this._doneReadingSource(Cr.NS_ERROR_UNEXPECTED);
+    }
+  },
+
+  // NSIOUTPUTSTREAMCALLBACK
+
+  /**
+   * Callback when data may be written to the output stream without blocking, or
+   * when the output stream has been closed.
+   *
+   * @param output : nsIAsyncOutputStream
+   *   the output stream on whose writability we've been waiting, also known as
+   *   this._sink
+   */
+  onOutputStreamReady(output) {
+    if (this._sink === null) {
+      return;
+    }
+
+    dumpn("*** onOutputStreamReady");
+
+    var pendingData = this._pendingData;
+    if (pendingData.length === 0) {
+      // There's no pending data to write.  The only way this can happen is if
+      // we're waiting on the output stream's closure, so we can respond to a
+      // copying failure as quickly as possible (rather than waiting for data to
+      // be available to read and then fail to be copied).  Therefore, we must
+      // be done now -- don't bother to attempt to write anything and wrap
+      // things up.
+      dumpn("!!! output stream closed prematurely, ending copy");
+
+      this._doneWritingToSink(Cr.NS_ERROR_UNEXPECTED);
+      return;
+    }
+
+    NS_ASSERT(!!pendingData[0].length, "queued up an empty quantum?");
+
+    //
+    // Write out the first pending quantum of data.  The possible errors here
+    // are:
+    //
+    //   The write might fail because we can't write that much data
+    //     Okay, we've written what we can now, so re-queue what's left and
+    //     finish writing it out later.
+    //   The write failed because the stream was closed
+    //     Discard pending data that we can no longer write, stop reading, and
+    //     signal that copying finished.
+    //   Some other error occurred.
+    //     Same as if the stream were closed, but notify with the status
+    //     NS_ERROR_UNEXPECTED so the observer knows something was wonky.
+    //
+
+    try {
+      var quantum = pendingData[0];
+
+      // XXX |quantum| isn't guaranteed to be ASCII, so we're relying on
+      //     undefined behavior!  We're only using this because writeByteArray
+      //     is unusably broken for asynchronous output streams; see bug 532834
+      //     for details.
+      var bytesWritten = output.write(quantum, quantum.length);
+      if (bytesWritten === quantum.length) {
+        pendingData.shift();
+      } else {
+        pendingData[0] = quantum.substring(bytesWritten);
+      }
+
+      dumpn("*** wrote " + bytesWritten + " bytes of data");
+    } catch (e) {
+      if (wouldBlock(e)) {
+        NS_ASSERT(
+          !!pendingData.length,
+          "stream-blocking exception with no data to write?"
+        );
+        NS_ASSERT(
+          !!pendingData[0].length,
+          "stream-blocking exception with empty quantum?"
+        );
+        this._waitToWriteData();
+        return;
+      }
+
+      if (streamClosed(e)) {
+        dumpn("!!! output stream prematurely closed, signaling error...");
+      } else {
+        dumpn("!!! unknown error: " + e + ", quantum=" + quantum);
+      }
+
+      this._doneWritingToSink(Cr.NS_ERROR_UNEXPECTED);
+      return;
+    }
+
+    // The day is ours!  Quantum written, now let's see if we have more data
+    // still to write.
+    try {
+      if (pendingData.length) {
+        this._waitToWriteData();
+        return;
+      }
+    } catch (e) {
+      dumpn("!!! unexpected error waiting to write pending data: " + e);
+      this._doneWritingToSink(Cr.NS_ERROR_UNEXPECTED);
+      return;
+    }
+
+    // Okay, we have no more pending data to write -- but might we get more in
+    // the future?
+    if (this._source !== null) {
+      /*
+       * If we might, then wait for the output stream to be closed.  (We wait
+       * only for closure because we have no data to write -- and if we waited
+       * for a specific amount of data, we would get repeatedly notified for no
+       * reason if over time the output stream permitted more and more data to
+       * be written to it without blocking.)
+       */
+      this._waitForSinkClosure();
+    } else {
+      /*
+       * On the other hand, if we can't have more data because the input
+       * stream's gone away, then it's time to notify of copy completion.
+       * Victory!
+       */
+      this._sink = null;
+      this._cancelOrDispatchCancelCallback(Cr.NS_OK);
+    }
+  },
+
+  // NSIREQUEST
+
+  /** Returns true if the cancel observer hasn't been notified yet. */
+  isPending() {
+    return !this._completed;
+  },
+
+  /** Not implemented, don't use! */
+  suspend: notImplemented,
+  /** Not implemented, don't use! */
+  resume: notImplemented,
+
+  /**
+   * Cancels data reading from input, asynchronously writes out any pending
+   * data, and causes the observer to be notified with the given error code when
+   * all writing has finished.
+   *
+   * @param status : nsresult
+   *   the status to pass to the observer when data copying has been canceled
+   */
+  cancel(status) {
+    dumpn("*** cancel(" + status.toString(16) + ")");
+
+    if (this._canceled) {
+      dumpn("*** suppressing a late cancel");
+      return;
+    }
+
+    this._canceled = true;
+    this.status = status;
+
+    // We could be in the middle of absolutely anything at this point.  Both
+    // input and output might still be around, we might have pending data to
+    // write, and in general we know nothing about the state of the world.  We
+    // therefore must assume everything's in progress and take everything to its
+    // final steady state (or so far as it can go before we need to finish
+    // writing out remaining data).
+
+    this._doneReadingSource(status);
+  },
+
+  // PRIVATE IMPLEMENTATION
+
+  /**
+   * Stop reading input if we haven't already done so, passing e as the status
+   * when closing the stream, and kick off a copy-completion notice if no more
+   * data remains to be written.
+   *
+   * @param e : nsresult
+   *   the status to be used when closing the input stream
+   */
+  _doneReadingSource(e) {
+    dumpn("*** _doneReadingSource(0x" + e.toString(16) + ")");
+
+    this._finishSource(e);
+    if (this._pendingData.length === 0) {
+      this._sink = null;
+    } else {
+      NS_ASSERT(this._sink !== null, "null output?");
+    }
+
+    // If we've written out all data read up to this point, then it's time to
+    // signal completion.
+    if (this._sink === null) {
+      NS_ASSERT(this._pendingData.length === 0, "pending data still?");
+      this._cancelOrDispatchCancelCallback(e);
+    }
+  },
+
+  /**
+   * Stop writing output if we haven't already done so, discard any data that
+   * remained to be sent, close off input if it wasn't already closed, and kick
+   * off a copy-completion notice.
+   *
+   * @param e : nsresult
+   *   the status to be used when closing input if it wasn't already closed
+   */
+  _doneWritingToSink(e) {
+    dumpn("*** _doneWritingToSink(0x" + e.toString(16) + ")");
+
+    this._pendingData.length = 0;
+    this._sink = null;
+    this._doneReadingSource(e);
+  },
+
+  /**
+   * Completes processing of this copy: either by canceling the copy if it
+   * hasn't already been canceled using the provided status, or by dispatching
+   * the cancel callback event (with the originally provided status, of course)
+   * if it already has been canceled.
+   *
+   * @param status : nsresult
+   *   the status code to use to cancel this, if this hasn't already been
+   *   canceled
+   */
+  _cancelOrDispatchCancelCallback(status) {
+    dumpn("*** _cancelOrDispatchCancelCallback(" + status + ")");
+
+    NS_ASSERT(this._source === null, "should have finished input");
+    NS_ASSERT(this._sink === null, "should have finished output");
+    NS_ASSERT(this._pendingData.length === 0, "should have no pending data");
+
+    if (!this._canceled) {
+      this.cancel(status);
+      return;
+    }
+
+    var self = this;
+    var event = {
+      run() {
+        dumpn("*** onStopRequest async callback");
+
+        self._completed = true;
+        try {
+          self._observer.onStopRequest(self, self.status);
+        } catch (e) {
+          NS_ASSERT(
+            false,
+            "how are we throwing an exception here?  we control " +
+              "all the callers!  " +
+              e
+          );
+        }
+      },
+    };
+
+    Services.tm.currentThread.dispatch(event, Ci.nsIThread.DISPATCH_NORMAL);
+  },
+
+  /**
+   * Kicks off another wait for more data to be available from the input stream.
+   */
+  _waitToReadData() {
+    dumpn("*** _waitToReadData");
+    this._source.asyncWait(
+      this,
+      0,
+      Response.SEGMENT_SIZE,
+      Services.tm.mainThread
+    );
+  },
+
+  /**
+   * Kicks off another wait until data can be written to the output stream.
+   */
+  _waitToWriteData() {
+    dumpn("*** _waitToWriteData");
+
+    var pendingData = this._pendingData;
+    NS_ASSERT(!!pendingData.length, "no pending data to write?");
+    NS_ASSERT(!!pendingData[0].length, "buffered an empty write?");
+
+    this._sink.asyncWait(
+      this,
+      0,
+      pendingData[0].length,
+      Services.tm.mainThread
+    );
+  },
+
+  /**
+   * Kicks off a wait for the sink to which data is being copied to be closed.
+   * We wait for stream closure when we don't have any data to be copied, rather
+   * than waiting to write a specific amount of data.  We can't wait to write
+   * data because the sink might be infinitely writable, and if no data appears
+   * in the source for a long time we might have to spin quite a bit waiting to
+   * write, waiting to write again, &c.  Waiting on stream closure instead means
+   * we'll get just one notification if the sink dies.  Note that when data
+   * starts arriving from the sink we'll resume waiting for data to be written,
+   * dropping this closure-only callback entirely.
+   */
+  _waitForSinkClosure() {
+    dumpn("*** _waitForSinkClosure");
+
+    this._sink.asyncWait(
+      this,
+      Ci.nsIAsyncOutputStream.WAIT_CLOSURE_ONLY,
+      0,
+      Services.tm.mainThread
+    );
+  },
+
+  /**
+   * Closes input with the given status, if it hasn't already been closed;
+   * otherwise a no-op.
+   *
+   * @param status : nsresult
+   *   status code use to close the source stream if necessary
+   */
+  _finishSource(status) {
+    dumpn("*** _finishSource(" + status.toString(16) + ")");
+
+    if (this._source !== null) {
+      this._source.closeWithStatus(status);
+      this._source = null;
+    }
+  },
+};
+
+/**
+ * A container for utility functions used with HTTP headers.
+ */
+const headerUtils = {
+  /**
+   * Normalizes fieldName (by converting it to lowercase) and ensures it is a
+   * valid header field name (although not necessarily one specified in RFC
+   * 2616).
+   *
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldName does not match the field-name production in RFC 2616
+   * @returns string
+   *   fieldName converted to lowercase if it is a valid header, for characters
+   *   where case conversion is possible
+   */
+  normalizeFieldName(fieldName) {
+    if (fieldName == "") {
+      dumpn("*** Empty fieldName");
+      throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+    }
+
+    for (var i = 0, sz = fieldName.length; i < sz; i++) {
+      if (!IS_TOKEN_ARRAY[fieldName.charCodeAt(i)]) {
+        dumpn(fieldName + " is not a valid header field name!");
+        throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+      }
+    }
+
+    return fieldName.toLowerCase();
+  },
+
+  /**
+   * Ensures that fieldValue is a valid header field value (although not
+   * necessarily as specified in RFC 2616 if the corresponding field name is
+   * part of the HTTP protocol), normalizes the value if it is, and
+   * returns the normalized value.
+   *
+   * @param fieldValue : string
+   *   a value to be normalized as an HTTP header field value
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldValue does not match the field-value production in RFC 2616
+   * @returns string
+   *   fieldValue as a normalized HTTP header field value
+   */
+  normalizeFieldValue(fieldValue) {
+    // field-value    = *( field-content | LWS )
+    // field-content  = <the OCTETs making up the field-value
+    //                  and consisting of either *TEXT or combinations
+    //                  of token, separators, and quoted-string>
+    // TEXT           = <any OCTET except CTLs,
+    //                  but including LWS>
+    // LWS            = [CRLF] 1*( SP | HT )
+    //
+    // quoted-string  = ( <"> *(qdtext | quoted-pair ) <"> )
+    // qdtext         = <any TEXT except <">>
+    // quoted-pair    = "\" CHAR
+    // CHAR           = <any US-ASCII character (octets 0 - 127)>
+
+    // Any LWS that occurs between field-content MAY be replaced with a single
+    // SP before interpreting the field value or forwarding the message
+    // downstream (section 4.2); we replace 1*LWS with a single SP
+    var val = fieldValue.replace(/(?:(?:\r\n)?[ \t]+)+/g, " ");
+
+    // remove leading/trailing LWS (which has been converted to SP)
+    val = val.replace(/^ +/, "").replace(/ +$/, "");
+
+    // that should have taken care of all CTLs, so val should contain no CTLs
+    dumpn("*** Normalized value: '" + val + "'");
+    for (var i = 0, len = val.length; i < len; i++) {
+      if (isCTL(val.charCodeAt(i))) {
+        dump("*** Char " + i + " has charcode " + val.charCodeAt(i));
+        throw Components.Exception("", Cr.NS_ERROR_INVALID_ARG);
+      }
+    }
+
+    // XXX disallows quoted-pair where CHAR is a CTL -- will not invalidly
+    //     normalize, however, so this can be construed as a tightening of the
+    //     spec and not entirely as a bug
+    return val;
+  },
+};
+
+/**
+ * Converts the given string into a string which is safe for use in an HTML
+ * context.
+ *
+ * @param str : string
+ *   the string to make HTML-safe
+ * @returns string
+ *   an HTML-safe version of str
+ */
+function htmlEscape(str) {
+  // this is naive, but it'll work
+  var s = "";
+  for (var i = 0; i < str.length; i++) {
+    s += "&#" + str.charCodeAt(i) + ";";
+  }
+  return s;
+}
+
+/**
+ * Constructs an object representing an HTTP version (see section 3.1).
+ *
+ * @param versionString
+ *   a string of the form "#.#", where # is an non-negative decimal integer with
+ *   or without leading zeros
+ * @throws
+ *   if versionString does not specify a valid HTTP version number
+ */
+function nsHttpVersion(versionString) {
+  var matches = /^(\d+)\.(\d+)$/.exec(versionString);
+  if (!matches) {
+    throw new Error("Not a valid HTTP version!");
+  }
+
+  /** The major version number of this, as a number. */
+  this.major = parseInt(matches[1], 10);
+
+  /** The minor version number of this, as a number. */
+  this.minor = parseInt(matches[2], 10);
+
+  if (
+    isNaN(this.major) ||
+    isNaN(this.minor) ||
+    this.major < 0 ||
+    this.minor < 0
+  ) {
+    throw new Error("Not a valid HTTP version!");
+  }
+}
+nsHttpVersion.prototype = {
+  /**
+   * Returns the standard string representation of the HTTP version represented
+   * by this (e.g., "1.1").
+   */
+  toString() {
+    return this.major + "." + this.minor;
+  },
+
+  /**
+   * Returns true if this represents the same HTTP version as otherVersion,
+   * false otherwise.
+   *
+   * @param otherVersion : nsHttpVersion
+   *   the version to compare against this
+   */
+  equals(otherVersion) {
+    return this.major == otherVersion.major && this.minor == otherVersion.minor;
+  },
+
+  /** True if this >= otherVersion, false otherwise. */
+  atLeast(otherVersion) {
+    return (
+      this.major > otherVersion.major ||
+      (this.major == otherVersion.major && this.minor >= otherVersion.minor)
+    );
+  },
+};
+
+nsHttpVersion.HTTP_1_0 = new nsHttpVersion("1.0");
+nsHttpVersion.HTTP_1_1 = new nsHttpVersion("1.1");
+
+/**
+ * An object which stores HTTP headers for a request or response.
+ *
+ * Note that since headers are case-insensitive, this object converts headers to
+ * lowercase before storing them.  This allows the getHeader and hasHeader
+ * methods to work correctly for any case of a header, but it means that the
+ * values returned by .enumerator may not be equal case-sensitively to the
+ * values passed to setHeader when adding headers to this.
+ */
+export function nsHttpHeaders() {
+  /**
+   * A hash of headers, with header field names as the keys and header field
+   * values as the values.  Header field names are case-insensitive, but upon
+   * insertion here they are converted to lowercase.  Header field values are
+   * normalized upon insertion to contain no leading or trailing whitespace.
+   *
+   * Note also that per RFC 2616, section 4.2, two headers with the same name in
+   * a message may be treated as one header with the same field name and a field
+   * value consisting of the separate field values joined together with a "," in
+   * their original order.  This hash stores multiple headers with the same name
+   * in this manner.
+   */
+  this._headers = {};
+}
+nsHttpHeaders.prototype = {
+  /**
+   * Sets the header represented by name and value in this.
+   *
+   * @param name : string
+   *   the header name
+   * @param value : string
+   *   the header value
+   * @throws NS_ERROR_INVALID_ARG
+   *   if name or value is not a valid header component
+   */
+  setHeader(fieldName, fieldValue, merge) {
+    var name = headerUtils.normalizeFieldName(fieldName);
+    var value = headerUtils.normalizeFieldValue(fieldValue);
+
+    // The following three headers are stored as arrays because their real-world
+    // syntax prevents joining individual headers into a single header using
+    // ",".  See also <https://hg.mozilla.org/mozilla-central/diff/9b2a99adc05e/netwerk/protocol/http/src/nsHttpHeaderArray.cpp#l77>
+    if (merge && name in this._headers) {
+      if (
+        name === "www-authenticate" ||
+        name === "proxy-authenticate" ||
+        name === "set-cookie"
+      ) {
+        this._headers[name].push(value);
+      } else {
+        this._headers[name][0] += "," + value;
+        NS_ASSERT(
+          this._headers[name].length === 1,
+          "how'd a non-special header have multiple values?"
+        );
+      }
+    } else {
+      this._headers[name] = [value];
+    }
+  },
+
+  setHeaderNoCheck(fieldName, fieldValue) {
+    var name = headerUtils.normalizeFieldName(fieldName);
+    var value = headerUtils.normalizeFieldValue(fieldValue);
+    if (name in this._headers) {
+      this._headers[name].push(value);
+    } else {
+      this._headers[name] = [value];
+    }
+  },
+
+  /**
+   * Returns the value for the header specified by this.
+   *
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldName does not constitute a valid header field name
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if the given header does not exist in this
+   * @returns string
+   *   the field value for the given header, possibly with non-semantic changes
+   *   (i.e., leading/trailing whitespace stripped, whitespace runs replaced
+   *   with spaces, etc.) at the option of the implementation; multiple
+   *   instances of the header will be combined with a comma, except for
+   *   the three headers noted in the description of getHeaderValues
+   */
+  getHeader(fieldName) {
+    return this.getHeaderValues(fieldName).join("\n");
+  },
+
+  /**
+   * Returns the value for the header specified by fieldName as an array.
+   *
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldName does not constitute a valid header field name
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if the given header does not exist in this
+   * @returns [string]
+   *   an array of all the header values in this for the given
+   *   header name.  Header values will generally be collapsed
+   *   into a single header by joining all header values together
+   *   with commas, but certain headers (Proxy-Authenticate,
+   *   WWW-Authenticate, and Set-Cookie) violate the HTTP spec
+   *   and cannot be collapsed in this manner.  For these headers
+   *   only, the returned array may contain multiple elements if
+   *   that header has been added more than once.
+   */
+  getHeaderValues(fieldName) {
+    var name = headerUtils.normalizeFieldName(fieldName);
+
+    if (name in this._headers) {
+      return this._headers[name];
+    }
+    throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+  },
+
+  /**
+   * Returns true if a header with the given field name exists in this, false
+   * otherwise.
+   *
+   * @param fieldName : string
+   *   the field name whose existence is to be determined in this
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldName does not constitute a valid header field name
+   * @returns boolean
+   *   true if the header's present, false otherwise
+   */
+  hasHeader(fieldName) {
+    var name = headerUtils.normalizeFieldName(fieldName);
+    return name in this._headers;
+  },
+
+  /**
+   * Returns a new enumerator over the field names of the headers in this, as
+   * nsISupportsStrings.  The names returned will be in lowercase, regardless of
+   * how they were input using setHeader (header names are case-insensitive per
+   * RFC 2616).
+   */
+  get enumerator() {
+    var headers = [];
+    for (var i in this._headers) {
+      var supports = new SupportsString();
+      supports.data = i;
+      headers.push(supports);
+    }
+
+    return new nsSimpleEnumerator(headers);
+  },
+};
+
+/**
+ * Constructs an nsISimpleEnumerator for the given array of items.
+ *
+ * @param items : Array
+ *   the items, which must all implement nsISupports
+ */
+function nsSimpleEnumerator(items) {
+  this._items = items;
+  this._nextIndex = 0;
+}
+nsSimpleEnumerator.prototype = {
+  hasMoreElements() {
+    return this._nextIndex < this._items.length;
+  },
+  getNext() {
+    if (!this.hasMoreElements()) {
+      throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+
+    return this._items[this._nextIndex++];
+  },
+  [Symbol.iterator]() {
+    return this._items.values();
+  },
+  QueryInterface: ChromeUtils.generateQI(["nsISimpleEnumerator"]),
+};
+
+/**
+ * A representation of the data in an HTTP request.
+ *
+ * @param port : uint
+ *   the port on which the server receiving this request runs
+ */
+function Request(port) {
+  /** Method of this request, e.g. GET or POST. */
+  this._method = "";
+
+  /** Path of the requested resource; empty paths are converted to '/'. */
+  this._path = "";
+
+  /** Query string, if any, associated with this request (not including '?'). */
+  this._queryString = "";
+
+  /** Scheme of requested resource, usually http, always lowercase. */
+  this._scheme = "http";
+
+  /** Hostname on which the requested resource resides. */
+  this._host = undefined;
+
+  /** Port number over which the request was received. */
+  this._port = port;
+
+  var bodyPipe = new Pipe(false, false, 0, PR_UINT32_MAX, null);
+
+  /** Stream from which data in this request's body may be read. */
+  this._bodyInputStream = bodyPipe.inputStream;
+
+  /** Stream to which data in this request's body is written. */
+  this._bodyOutputStream = bodyPipe.outputStream;
+
+  /**
+   * The headers in this request.
+   */
+  this._headers = new nsHttpHeaders();
+
+  /**
+   * For the addition of ad-hoc properties and new functionality without having
+   * to change nsIHttpRequest every time; currently lazily created, as its only
+   * use is in directory listings.
+   */
+  this._bag = null;
+}
+Request.prototype = {
+  // SERVER METADATA
+
+  //
+  // see nsIHttpRequest.scheme
+  //
+  get scheme() {
+    return this._scheme;
+  },
+
+  //
+  // see nsIHttpRequest.host
+  //
+  get host() {
+    return this._host;
+  },
+
+  //
+  // see nsIHttpRequest.port
+  //
+  get port() {
+    return this._port;
+  },
+
+  // REQUEST LINE
+
+  //
+  // see nsIHttpRequest.method
+  //
+  get method() {
+    return this._method;
+  },
+
+  //
+  // see nsIHttpRequest.httpVersion
+  //
+  get httpVersion() {
+    return this._httpVersion.toString();
+  },
+
+  //
+  // see nsIHttpRequest.path
+  //
+  get path() {
+    return this._path;
+  },
+
+  //
+  // see nsIHttpRequest.queryString
+  //
+  get queryString() {
+    return this._queryString;
+  },
+
+  // HEADERS
+
+  //
+  // see nsIHttpRequest.getHeader
+  //
+  getHeader(name) {
+    return this._headers.getHeader(name);
+  },
+
+  //
+  // see nsIHttpRequest.hasHeader
+  //
+  hasHeader(name) {
+    return this._headers.hasHeader(name);
+  },
+
+  //
+  // see nsIHttpRequest.headers
+  //
+  get headers() {
+    return this._headers.enumerator;
+  },
+
+  //
+  // see nsIPropertyBag.enumerator
+  //
+  get enumerator() {
+    this._ensurePropertyBag();
+    return this._bag.enumerator;
+  },
+
+  //
+  // see nsIHttpRequest.headers
+  //
+  get bodyInputStream() {
+    return this._bodyInputStream;
+  },
+
+  //
+  // see nsIPropertyBag.getProperty
+  //
+  getProperty(name) {
+    this._ensurePropertyBag();
+    return this._bag.getProperty(name);
+  },
+
+  // NSISUPPORTS
+
+  //
+  // see nsISupports.QueryInterface
+  //
+  QueryInterface: ChromeUtils.generateQI(["nsIHttpRequest"]),
+
+  // PRIVATE IMPLEMENTATION
+
+  /** Ensures a property bag has been created for ad-hoc behaviors. */
+  _ensurePropertyBag() {
+    if (!this._bag) {
+      this._bag = new WritablePropertyBag();
+    }
+  },
+};
diff --git a/netwerk/test/httpserver/moz.build b/netwerk/test/httpserver/moz.build
new file mode 100644
index 0000000000..f4c978b160
--- /dev/null
+++ b/netwerk/test/httpserver/moz.build
@@ -0,0 +1,21 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+XPIDL_SOURCES += [
+    "nsIHttpServer.idl",
+]
+
+XPIDL_MODULE = "test_necko"
+
+XPCSHELL_TESTS_MANIFESTS += ["test/xpcshell.toml"]
+
+EXTRA_COMPONENTS += [
+    "httpd.sys.mjs",
+]
+
+TESTING_JS_MODULES += [
+    "httpd.sys.mjs",
+]
diff --git a/netwerk/test/httpserver/nsIHttpServer.idl b/netwerk/test/httpserver/nsIHttpServer.idl
new file mode 100644
index 0000000000..83614dbdb0
--- /dev/null
+++ b/netwerk/test/httpserver/nsIHttpServer.idl
@@ -0,0 +1,649 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIInputStream;
+interface nsIFile;
+interface nsIOutputStream;
+interface nsISimpleEnumerator;
+
+interface nsIHttpServer;
+interface nsIHttpServerStoppedCallback;
+interface nsIHttpRequestHandler;
+interface nsIHttpRequest;
+interface nsIHttpResponse;
+interface nsIHttpServerIdentity;
+
+/**
+ * An interface which represents an HTTP server.
+ */
+[scriptable, uuid(cea8812e-faa6-4013-9396-f9936cbb74ec)]
+interface nsIHttpServer : nsISupports
+{
+  /**
+   * Starts up this server, listening upon the given port.
+   *
+   * @param port
+   *   the port upon which listening should happen, or -1 if no specific port is
+   *   desired
+   * @throws NS_ERROR_ALREADY_INITIALIZED
+   *   if this server is already started
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if the server is not started and cannot be started on the desired port
+   *   (perhaps because the port is already in use or because the process does
+   *   not have privileges to do so)
+   * @note
+   *   Behavior is undefined if this method is called after stop() has been
+   *   called on this but before the provided callback function has been
+   *   called.
+   */
+  void start(in long port);
+
+  /**
+   * Starts up this server, listening upon the given port on a ipv6 adddress.
+   *
+   * @param port
+   *   the port upon which listening should happen, or -1 if no specific port is
+   *   desired
+   * @throws NS_ERROR_ALREADY_INITIALIZED
+   *   if this server is already started
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if the server is not started and cannot be started on the desired port
+   *   (perhaps because the port is already in use or because the process does
+   *   not have privileges to do so)
+   * @note
+   *   Behavior is undefined if this method is called after stop() has been
+   *   called on this but before the provided callback function has been
+   *   called.
+   */
+  void start_ipv6(in long port);
+
+  /**
+   * Like the two functions above, but this server supports both IPv6 and
+   * IPv4 addresses.
+   */
+  void start_dualStack(in long port);
+
+  /**
+   * Shuts down this server if it is running (including the period of time after
+   * stop() has been called but before the provided callback has been called).
+   *
+   * @param callback
+   *   an asynchronous callback used to notify the user when this server is
+   *   stopped and all pending requests have been fully served
+   * @throws NS_ERROR_NULL_POINTER
+   *   if callback is null
+   * @throws NS_ERROR_UNEXPECTED
+   *   if this server is not running
+   */
+  void stop(in nsIHttpServerStoppedCallback callback);
+
+  /**
+   * Associates the local file represented by the string file with all requests
+   * which match request.
+   *
+   * @param path
+   *   the path which is to be mapped to the given file; must begin with "/" and
+   *   be a valid URI path (i.e., no query string, hash reference, etc.)
+   * @param file
+   *   the file to serve for the given path, or null to remove any mapping that
+   *   might exist; this file must exist for the lifetime of the server
+   * @param handler
+   *   an optional object which can be used to handle any further changes.
+   */
+  void registerFile(in string path,
+                    in nsIFile file,
+                    [optional] in nsIHttpRequestHandler handler);
+
+  /**
+   * Registers a custom path handler.
+   *
+   * @param path
+   *   the path on the server (beginning with a "/") which is to be handled by
+   *   handler; this path must not include a query string or hash component; it
+   *   also should usually be canonicalized, since most browsers will do so
+   *   before sending otherwise-matching requests
+   * @param handler
+   *   an object which will handle any requests for the given path, or null to
+   *   remove any existing handler; if while the server is running the handler
+   *   throws an exception while responding to a request, an HTTP 500 response
+   *   will be returned
+   * @throws NS_ERROR_INVALID_ARG
+   *   if path does not begin with a "/"
+   */
+  void registerPathHandler(in string path, in nsIHttpRequestHandler handler);
+
+  /**
+   * Registers a custom prefix handler.
+   *
+   * @param prefix
+   *   the path on the server (beginning and ending with "/") which is to be
+   *   handled by handler; this path must not include a query string or hash
+   *   component. All requests that start with this prefix will be directed to
+   *   the given handler.
+   * @param handler
+   *   an object which will handle any requests for the given path, or null to
+   *   remove any existing handler; if while the server is running the handler
+   *   throws an exception while responding to a request, an HTTP 500 response
+   *   will be returned
+   * @throws NS_ERROR_INVALID_ARG
+   *   if path does not begin with a "/" or does not end with a "/"
+   */
+  void registerPrefixHandler(in string prefix, in nsIHttpRequestHandler handler);
+
+  /**
+   * Registers a custom error page handler.
+   *
+   * @param code
+   *   the error code which is to be handled by handler
+   * @param handler
+   *   an object which will handle any requests which generate the given status
+   *   code, or null to remove any existing handler.  If the handler throws an
+   *   exception during server operation, fallback is to the genericized error
+   *   handler (the x00 version), then to 500, using a user-defined error
+   *   handler if one exists or the server default handler otherwise.  Fallback
+   *   will never occur from a user-provided handler that throws to the same
+   *   handler as provided by the server, e.g. a throwing user 404 falls back to
+   *   400, not a server-provided 404 that might not throw.
+   * @note
+   *   If the error handler handles HTTP 500 and throws, behavior is undefined.
+   */
+  void registerErrorHandler(in unsigned long code, in nsIHttpRequestHandler handler);
+
+  /**
+   * Maps all requests to paths beneath path to the corresponding file beneath
+   * dir.
+   *
+   * @param path
+   *   the absolute path on the server against which requests will be served
+   *   from dir (e.g., "/", "/foo/", etc.); must begin and end with a forward
+   *   slash
+   * @param dir
+   *   the directory to be used to serve all requests for paths underneath path
+   *   (except those further overridden by another, deeper path registered with
+   *   another directory); if null, any current mapping for the given path is
+   *   removed
+   * @throws NS_ERROR_INVALID_ARG
+   *   if dir is non-null and does not exist or is not a directory, or if path
+   *   does not begin with and end with a forward slash
+   */
+  void registerDirectory(in string path, in nsIFile dir);
+
+  /**
+   * Associates files with the given extension with the given Content-Type when
+   * served by this server, in the absence of any file-specific information
+   * about the desired Content-Type.  If type is empty, removes any extant
+   * mapping, if one is present.
+   *
+   * @throws NS_ERROR_INVALID_ARG
+   *   if the given type is not a valid header field value, i.e. if it doesn't
+   *   match the field-value production in RFC 2616
+   * @note
+   *   No syntax checking is done of the given type, beyond ensuring that it is
+   *   a valid header field value.  Behavior when not given a string matching
+   *   the media-type production in RFC 2616 section 3.7 is undefined.
+   *   Implementations may choose to define specific behavior for types which do
+   *   not match the production, such as for CGI functionality.
+   * @note
+   *   Implementations MAY treat type as a trusted argument; users who fail to
+   *   generate this string from trusted data risk security vulnerabilities.
+   */
+  void registerContentType(in string extension, in string type);
+
+  /**
+   * Sets the handler used to display the contents of a directory if
+   * the directory contains no index page.
+   *
+   * @param handler
+   *   an object which will handle any requests for directories which
+   *   do not contain index pages, or null to reset to the default
+   *   index handler; if while the server is running the handler
+   *   throws an exception while responding to a request, an HTTP 500
+   *   response will be returned.  An nsIFile corresponding to the
+   *   directory is available from the metadata object passed to the
+   *   handler, under the key "directory".
+   */
+  void setIndexHandler(in nsIHttpRequestHandler handler);
+
+  /** Represents the locations at which this server is reachable. */
+  readonly attribute nsIHttpServerIdentity identity;
+
+  /**
+   * Retrieves the string associated with the given key in this, for the given
+   * path's saved state.  All keys are initially associated with the empty
+   * string.
+   */
+  AString getState(in AString path, in AString key);
+
+  /**
+   * Sets the string associated with the given key in this, for the given path's
+   * saved state.
+   */
+  void setState(in AString path, in AString key, in AString value);
+
+  /**
+   * Retrieves the string associated with the given key in this, in
+   * entire-server saved state.  All keys are initially associated with the
+   * empty string.
+   */
+  AString getSharedState(in AString key);
+
+  /**
+   * Sets the string associated with the given key in this, in entire-server
+   * saved state.
+   */
+  void setSharedState(in AString key, in AString value);
+
+  /**
+   * Retrieves the object associated with the given key in this in
+   * object-valued saved state.  All keys are initially associated with null.
+   */
+  nsISupports getObjectState(in AString key);
+
+  /**
+   * Sets the object associated with the given key in this in object-valued
+   * saved state.  The value may be null.
+   */
+  void setObjectState(in AString key, in nsISupports value);
+};
+
+/**
+ * An interface through which a notification of the complete stopping (socket
+ * closure, in-flight requests all fully served and responded to) of an HTTP
+ * server may be received.
+ */
+[scriptable, function, uuid(925a6d33-9937-4c63-abe1-a1c56a986455)]
+interface nsIHttpServerStoppedCallback : nsISupports
+{
+  /** Called when the corresponding server has been fully stopped. */
+  void onStopped();
+};
+
+/**
+ * Represents a set of names for a server, one of which is the primary name for
+ * the server and the rest of which are secondary.  By default every server will
+ * contain ("http", "localhost", port) and ("http", "127.0.0.1", port) as names,
+ * where port is what was provided to the corresponding server when started;
+ * however, except for their being removed when the corresponding server stops
+ * they have no special importance.
+ */
+[scriptable, uuid(a89de175-ae8e-4c46-91a5-0dba99bbd284)]
+interface nsIHttpServerIdentity : nsISupports
+{
+  /**
+   * The primary scheme at which the corresponding server is located, defaulting
+   * to 'http'.  This name will be the value of nsIHttpRequest.scheme for
+   * HTTP/1.0 requests.
+   *
+   * This value is always set when the corresponding server is running.  If the
+   * server is not running, this value is set only if it has been set to a
+   * non-default name using setPrimary.  In this case reading this value will
+   * throw NS_ERROR_NOT_INITIALIZED.
+   */
+  readonly attribute string primaryScheme;
+
+  /**
+   * The primary name by which the corresponding server is known, defaulting to
+   * 'localhost'.  This name will be the value of nsIHttpRequest.host for
+   * HTTP/1.0 requests.
+   *
+   * This value is always set when the corresponding server is running.  If the
+   * server is not running, this value is set only if it has been set to a
+   * non-default name using setPrimary.  In this case reading this value will
+   * throw NS_ERROR_NOT_INITIALIZED.
+   */
+  readonly attribute string primaryHost;
+
+  /**
+   * The primary port on which the corresponding server runs, defaulting to the
+   * associated server's port.  This name will be the value of
+   * nsIHttpRequest.port for HTTP/1.0 requests.
+   *
+   * This value is always set when the corresponding server is running.  If the
+   * server is not running, this value is set only if it has been set to a
+   * non-default name using setPrimary.  In this case reading this value will
+   * throw NS_ERROR_NOT_INITIALIZED.
+   */
+  readonly attribute long primaryPort;
+
+  /**
+   * Adds a location at which this server may be accessed.
+   *
+   * @throws NS_ERROR_ILLEGAL_VALUE
+   *   if scheme or host do not match the scheme or host productions imported
+   *   into RFC 2616 from RFC 2396, or if port is not a valid port number
+   */
+  void add(in string scheme, in string host, in long port);
+
+  /**
+   * Removes this name from the list of names by which the corresponding server
+   * is known.  If name is also the primary name for the server, the primary
+   * name reverts to 'http://127.0.0.1' with the associated server's port.
+   *
+   * @throws NS_ERROR_ILLEGAL_VALUE
+   *   if scheme or host do not match the scheme or host productions imported
+   *   into RFC 2616 from RFC 2396, or if port is not a valid port number
+   * @returns
+   *   true if the given name was a name for this server, false otherwise
+   */
+  boolean remove(in string scheme, in string host, in long port);
+
+  /**
+   * Returns true if the given name is in this, false otherwise.
+   *
+   * @throws NS_ERROR_ILLEGAL_VALUE
+   *   if scheme or host do not match the scheme or host productions imported
+   *   into RFC 2616 from RFC 2396, or if port is not a valid port number
+   */
+  boolean has(in string scheme, in string host, in long port);
+
+  /**
+   * Returns the scheme for the name with the given host and port, if one is
+   * present; otherwise returns the empty string.
+   *
+   * @throws NS_ERROR_ILLEGAL_VALUE
+   *   if host does not match the host production imported into RFC 2616 from
+   *   RFC 2396, or if port is not a valid port number
+   */
+  string getScheme(in string host, in long port);
+
+  /**
+   * Designates the given name as the primary name in this and adds it to this
+   * if it is not already present.
+   *
+   * @throws NS_ERROR_ILLEGAL_VALUE
+   *   if scheme or host do not match the scheme or host productions imported
+   *   into RFC 2616 from RFC 2396, or if port is not a valid port number
+   */
+  void setPrimary(in string scheme, in string host, in long port);
+};
+
+/**
+ * A representation of a handler for HTTP requests.  The handler is used by
+ * calling its .handle method with data for an incoming request; it is the
+ * handler's job to use that data as it sees fit to make the desired response.
+ *
+ * @note
+ *   This interface uses the [function] attribute, so you can pass a
+ *   script-defined function with the functionality of handle() to any
+ *   method which has a nsIHttpRequestHandler parameter, instead of wrapping
+ *   it in an otherwise empty object.
+ */
+[scriptable, function, uuid(2bbb4db7-d285-42b3-a3ce-142b8cc7e139)]
+interface nsIHttpRequestHandler : nsISupports
+{
+  /**
+   * Processes an HTTP request and initializes the passed-in response to reflect
+   * the correct HTTP response.
+   *
+   * If this method throws an exception, externally observable behavior depends
+   * upon whether is being processed asynchronously.  If such is the case, the
+   * output is some prefix (perhaps all, perhaps none, perhaps only some) of the
+   * data which would have been sent if, instead, the response had been finished
+   * at that point.  If no data has been written, the response has not had
+   * seizePower() called on it, and it is not being asynchronously created, an
+   * error handler will be invoked (usually 500 unless otherwise specified).
+   *
+   * Some uses of nsIHttpRequestHandler may require this method to never throw
+   * an exception; in the general case, however, this method may throw an
+   * exception (causing an HTTP 500 response to occur, if the above conditions
+   * are met).
+   *
+   * @param request
+   *   data representing an HTTP request
+   * @param response
+   *   an initially-empty response which must be modified to reflect the data
+   *   which should be sent as the response to the request described by metadata
+   */
+  void handle(in nsIHttpRequest request, in nsIHttpResponse response);
+};
+
+
+/**
+ * A representation of the data included in an HTTP request.
+ */
+[scriptable, uuid(978cf30e-ad73-42ee-8f22-fe0aaf1bf5d2)]
+interface nsIHttpRequest : nsISupports
+{
+  /**
+   * The request type for this request (see RFC 2616, section 5.1.1).
+   */
+  readonly attribute string method;
+
+  /**
+   * The scheme of the requested path, usually 'http' but might possibly be
+   * 'https' if some form of SSL tunneling is in use.  Note that this value
+   * cannot be accurately determined unless the incoming request used the
+   * absolute-path form of the request line; it defaults to 'http', so only
+   * if it is something else can you be entirely certain it's correct.
+   */
+  readonly attribute string scheme;
+
+  /**
+   * The host of the data being requested (e.g. "localhost" for the
+   * http://localhost:8080/file resource).  Note that the relevant port on the
+   * host is specified in this.port.  This value is in the ASCII character
+   * encoding.
+   */
+  readonly attribute string host;
+
+  /**
+   * The port on the server on which the request was received.
+   */
+  readonly attribute unsigned long port;
+
+  /**
+   * The requested path, without any query string (e.g. "/dir/file.txt").  It is
+   * guaranteed to begin with a "/".  The individual components in this string
+   * are URL-encoded.
+   */
+  readonly attribute string path;
+
+  /**
+   * The URL-encoded query string associated with this request, not including
+   * the initial "?", or "" if no query string was present.
+   */
+  readonly attribute string queryString;
+
+  /**
+   * A string containing the HTTP version of the request (i.e., "1.1").  Leading
+   * zeros for either component of the version will be omitted.  (In other
+   * words, if the request contains the version "1.01", this attribute will be
+   * "1.1"; see RFC 2616, section 3.1.)
+   */
+  readonly attribute string httpVersion;
+
+  /**
+   * Returns the value for the header in this request specified by fieldName.
+   *
+   * @param fieldName
+   *   the name of the field whose value is to be gotten; note that since HTTP
+   *   header field names are case-insensitive, this method produces equivalent
+   *   results for "HeAdER" and "hEADer" as fieldName
+   * @returns
+   *   The result is a string containing the individual values of the header,
+   *   usually separated with a comma.  The headers WWW-Authenticate,
+   *   Proxy-Authenticate, and Set-Cookie violate the HTTP specification,
+   *   however, and for these headers only the separator string is '\n'.
+   *
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldName does not constitute a valid header field name
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if the given header does not exist in this
+   */
+  string getHeader(in string fieldName);
+
+  /**
+   * Returns true if a header with the given field name exists in this, false
+   * otherwise.
+   *
+   * @param fieldName
+   *   the field name whose existence is to be determined in this; note that
+   *   since HTTP header field names are case-insensitive, this method produces
+   *   equivalent results for "HeAdER" and "hEADer" as fieldName
+   * @throws NS_ERROR_INVALID_ARG
+   *   if fieldName does not constitute a valid header field name
+   */
+  boolean hasHeader(in string fieldName);
+
+  /**
+   * An nsISimpleEnumerator of nsISupportsStrings over the names of the headers
+   * in this request.  The header field names in the enumerator may not
+   * necessarily have the same case as they do in the request itself.
+   */
+  readonly attribute nsISimpleEnumerator headers;
+
+  /**
+   * A stream from which data appearing in the body of this request can be read.
+   */
+  readonly attribute nsIInputStream bodyInputStream;
+};
+
+
+/**
+ * Represents an HTTP response, as described in RFC 2616, section 6.
+ */
+[scriptable, uuid(1acd16c2-dc59-42fa-9160-4f26c43c1c21)]
+interface nsIHttpResponse : nsISupports
+{
+  /**
+   * Sets the status line for this.  If this method is never called on this, the
+   * status line defaults to "HTTP/", followed by the server's default HTTP
+   * version (e.g. "1.1"), followed by " 200 OK".
+   *
+   * @param httpVersion
+   *   the HTTP version of this, as a string (e.g. "1.1"); if null, the server
+   *   default is used
+   * @param code
+   *   the numeric HTTP status code for this
+   * @param description
+   *   a human-readable description of code; may be null if no description is
+   *   desired
+   * @throws NS_ERROR_INVALID_ARG
+   *   if httpVersion is not a valid HTTP version string, statusCode is greater
+   *   than 999, or description contains invalid characters
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if this response is being processed asynchronously and data has been
+   *   written to this response's body, or if seizePower() has been called on
+   *   this
+   */
+  void setStatusLine(in string httpVersion,
+                     in unsigned short statusCode,
+                     in string description);
+
+  /**
+   * Sets the specified header in this.
+   *
+   * @param name
+   *   the name of the header; must match the field-name production per RFC 2616
+   * @param value
+   *   the value of the header; must match the field-value production per RFC
+   *   2616
+   * @param merge
+   *   when true, if the given header already exists in this, the values passed
+   *   to this function will be merged into the existing header, per RFC 2616
+   *   header semantics (except for the Set-Cookie, WWW-Authenticate, and
+   *   Proxy-Authenticate headers, which will treat each such merged header as
+   *   an additional instance of the header, for real-world compatibility
+   *   reasons); when false, replaces any existing header of the given name (if
+   *   any exists) with a new header with the specified value
+   * @throws NS_ERROR_INVALID_ARG
+   *   if name or value is not a valid header component
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if this response is being processed asynchronously and data has been
+   *   written to this response's body, or if seizePower() has been called on
+   *   this
+   */
+  void setHeader(in string name, in string value, in boolean merge);
+
+  /**
+   * This is used for testing our header handling, so header will be sent out
+   * without transformation. There can be multiple headers.
+   */
+  void setHeaderNoCheck(in string name, in string value);
+
+  /**
+   * A stream to which data appearing in the body of this response (or in the
+   * totality of the response if seizePower() is called) should be written.
+   * After this response has been designated as being processed asynchronously,
+   * or after seizePower() has been called on this, subsequent writes will no
+   * longer be buffered and will be written to the underlying transport without
+   * delaying until the entire response is constructed.  Write-through may or
+   * may not be synchronous in the implementation, and in any case particular
+   * behavior may not be observable to the HTTP client as intermediate buffers
+   * both in the server socket and in the client may delay written data; be
+   * prepared for delays at any time.
+   *
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if accessed after this response is fully constructed
+   */
+  readonly attribute nsIOutputStream bodyOutputStream;
+
+  /**
+   * Writes a string to the response's output stream.  This method is merely a
+   * convenient shorthand for writing the same data to bodyOutputStream
+   * directly.
+   *
+   * @note
+   *   This method is only guaranteed to work with ASCII data.
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if called after this response has been fully constructed
+   */
+  void write(in string data);
+
+  /**
+   * Signals that this response is being constructed asynchronously.  Requests
+   * are typically completely constructed during nsIHttpRequestHandler.handle;
+   * however, responses which require significant resources (time, memory,
+   * processing) to construct can be created and sent incrementally by calling
+   * this method during the call to nsIHttpRequestHandler.handle.  This method
+   * only has this effect when called during nsIHttpRequestHandler.handle;
+   * behavior is undefined if it is called at a later time.  It may be called
+   * multiple times with no ill effect, so long as each call occurs before
+   * finish() is called.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   if not initially called within a nsIHttpRequestHandler.handle call or if
+   *   called after this response has been finished
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if seizePower() has been called on this
+   */
+  void processAsync();
+
+  /**
+   * Seizes complete control of this response (and its connection) from the
+   * server, allowing raw and unfettered access to data being sent in the HTTP
+   * response.  Once this method has been called the only property which may be
+   * accessed without an exception being thrown is bodyOutputStream, and the
+   * only methods which may be accessed without an exception being thrown are
+   * write(), finish(), and seizePower() (which may be called multiple times
+   * without ill effect so long as all calls are otherwise allowed).
+   *
+   * After a successful call, all data subsequently written to the body of this
+   * response is written directly to the corresponding connection.  (Previously-
+   * written data is silently discarded.)  No status line or headers are sent
+   * before doing so; if the response handler wishes to write such data, it must
+   * do so manually.  Data generation completes only when finish() is called; it
+   * is not enough to simply call close() on bodyOutputStream.
+   *
+   * @throws NS_ERROR_NOT_AVAILABLE
+   *   if processAsync() has been called on this
+   * @throws NS_ERROR_UNEXPECTED
+   *   if finish() has been called on this
+   */
+  void seizePower();
+
+  /**
+   * Signals that construction of this response is complete and that it may be
+   * sent over the network to the client, or if seizePower() has been called
+   * signals that all data has been written and that the underlying connection
+   * may be closed.  This method may only be called after processAsync() or
+   * seizePower() has been called.  This method is idempotent.
+   *
+   * @throws NS_ERROR_UNEXPECTED
+   *   if processAsync() or seizePower() has not already been properly called
+   */
+  void finish();
+};
diff --git a/netwerk/test/httpserver/test/data/cern_meta/caret_test.txt^^ b/netwerk/test/httpserver/test/data/cern_meta/caret_test.txt^^
new file mode 100644
index 0000000000..b005a65fd2
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/caret_test.txt^^
@@ -0,0 +1 @@
+If this has goofy headers on it, it's a success.
diff --git a/netwerk/test/httpserver/test/data/cern_meta/caret_test.txt^^headers^ b/netwerk/test/httpserver/test/data/cern_meta/caret_test.txt^^headers^
new file mode 100644
index 0000000000..66e1522317
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/caret_test.txt^^headers^
@@ -0,0 +1,3 @@
+HTTP 500 This Isn't A Server Error
+Foo-RFC: 3092
+Shaving-Cream-Atom: Illudium Phosdex
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_both.html b/netwerk/test/httpserver/test/data/cern_meta/test_both.html
new file mode 100644
index 0000000000..db18ea5d7a
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_both.html
@@ -0,0 +1,2 @@
+This page is a text file served with status 501.  (That's really a lie, tho,
+because this is definitely Implemented.)
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_both.html^headers^ b/netwerk/test/httpserver/test/data/cern_meta/test_both.html^headers^
new file mode 100644
index 0000000000..bb3c16a2e2
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_both.html^headers^
@@ -0,0 +1,2 @@
+HTTP 501 Unimplemented
+Content-Type: text/plain
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_ctype_override.txt b/netwerk/test/httpserver/test/data/cern_meta/test_ctype_override.txt
new file mode 100644
index 0000000000..7235fa32a5
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_ctype_override.txt
@@ -0,0 +1,9 @@
+<html>
+<head>
+  <title>This is really HTML, not text</title>
+</head>
+<body>
+<p>This file is really HTML; the test_ctype_override.txt^headers^ file sets a
+  new header that overwrites the default text/plain header.</p>
+</body>
+</html>
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_ctype_override.txt^headers^ b/netwerk/test/httpserver/test/data/cern_meta/test_ctype_override.txt^headers^
new file mode 100644
index 0000000000..156209f9c8
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_ctype_override.txt^headers^
@@ -0,0 +1 @@
+Content-Type: text/html
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_status_override.html b/netwerk/test/httpserver/test/data/cern_meta/test_status_override.html
new file mode 100644
index 0000000000..fd243c640e
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_status_override.html
@@ -0,0 +1,9 @@
+<html>
+<head>
+  <title>This is a 404 page</title>
+</head>
+<body>
+<p>This page has a 404 HTTP status associated with it, via
+  <code>test_status_override.html^headers^</code>.</p>
+</body>
+</html>
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_status_override.html^headers^ b/netwerk/test/httpserver/test/data/cern_meta/test_status_override.html^headers^
new file mode 100644
index 0000000000..f438a05746
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_status_override.html^headers^
@@ -0,0 +1 @@
+HTTP 404 Can't Find This
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_status_override_nodesc.txt b/netwerk/test/httpserver/test/data/cern_meta/test_status_override_nodesc.txt
new file mode 100644
index 0000000000..4718ec282f
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_status_override_nodesc.txt
@@ -0,0 +1 @@
+This page has an HTTP status override without a description (it defaults to "").
diff --git a/netwerk/test/httpserver/test/data/cern_meta/test_status_override_nodesc.txt^headers^ b/netwerk/test/httpserver/test/data/cern_meta/test_status_override_nodesc.txt^headers^
new file mode 100644
index 0000000000..32da7632f9
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/cern_meta/test_status_override_nodesc.txt^headers^
@@ -0,0 +1 @@
+HTTP 732
diff --git a/netwerk/test/httpserver/test/data/name-scheme/bar.html^^ b/netwerk/test/httpserver/test/data/name-scheme/bar.html^^
new file mode 100644
index 0000000000..bed1f34c9f
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/bar.html^^
@@ -0,0 +1,10 @@
+<html>
+<head>
+  <title>Welcome to bar.html^</title>
+</head>
+<body>
+<p>This file is named with two trailing carets, so the last is stripped
+  away, producing bar.html^ as the final name.</p>
+</body>
+</html>
+
diff --git a/netwerk/test/httpserver/test/data/name-scheme/bar.html^^headers^ b/netwerk/test/httpserver/test/data/name-scheme/bar.html^^headers^
new file mode 100644
index 0000000000..04fbaa08fe
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/bar.html^^headers^
@@ -0,0 +1,2 @@
+HTTP 200 OK
+Content-Type: text/html
diff --git a/netwerk/test/httpserver/test/data/name-scheme/folder^^/ERROR_IF_SEE_THIS.txt^ b/netwerk/test/httpserver/test/data/name-scheme/folder^^/ERROR_IF_SEE_THIS.txt^
new file mode 100644
index 0000000000..dccee48e34
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/folder^^/ERROR_IF_SEE_THIS.txt^
@@ -0,0 +1 @@
+This file shouldn't be shown in directory listings.
diff --git a/netwerk/test/httpserver/test/data/name-scheme/folder^^/SHOULD_SEE_THIS.txt^^ b/netwerk/test/httpserver/test/data/name-scheme/folder^^/SHOULD_SEE_THIS.txt^^
new file mode 100644
index 0000000000..a8ee35a3b6
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/folder^^/SHOULD_SEE_THIS.txt^^
@@ -0,0 +1 @@
+This file should show up in directory listings as SHOULD_SEE_THIS.txt^.
diff --git a/netwerk/test/httpserver/test/data/name-scheme/folder^^/file.txt b/netwerk/test/httpserver/test/data/name-scheme/folder^^/file.txt
new file mode 100644
index 0000000000..2ceca8ca9e
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/folder^^/file.txt
@@ -0,0 +1,2 @@
+File in a directory named with a trailing caret (in the virtual FS; on disk it
+actually ends with two carets).
diff --git a/netwerk/test/httpserver/test/data/name-scheme/foo.html^ b/netwerk/test/httpserver/test/data/name-scheme/foo.html^
new file mode 100644
index 0000000000..a3efe8b5c3
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/foo.html^
@@ -0,0 +1,9 @@
+<html>
+<head>
+  <title>ERROR</title>
+</head>
+<body>
+<p>This file should never be served by the web server because its name ends
+  with a caret not followed by another caret.</p>
+</body>
+</html>
diff --git a/netwerk/test/httpserver/test/data/name-scheme/normal-file.txt b/netwerk/test/httpserver/test/data/name-scheme/normal-file.txt
new file mode 100644
index 0000000000..ab71eabaf0
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/name-scheme/normal-file.txt
@@ -0,0 +1 @@
+This should be seen.
diff --git a/netwerk/test/httpserver/test/data/ranges/empty.txt b/netwerk/test/httpserver/test/data/ranges/empty.txt
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/ranges/empty.txt
diff --git a/netwerk/test/httpserver/test/data/ranges/headers.txt b/netwerk/test/httpserver/test/data/ranges/headers.txt
new file mode 100644
index 0000000000..6cf83528c8
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/ranges/headers.txt
@@ -0,0 +1 @@
+Hello Kitty
diff --git a/netwerk/test/httpserver/test/data/ranges/headers.txt^headers^ b/netwerk/test/httpserver/test/data/ranges/headers.txt^headers^
new file mode 100644
index 0000000000..d0a633f042
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/ranges/headers.txt^headers^
@@ -0,0 +1 @@
+X-SJS-Header: customized
diff --git a/netwerk/test/httpserver/test/data/ranges/range.txt b/netwerk/test/httpserver/test/data/ranges/range.txt
new file mode 100644
index 0000000000..ab71eabaf0
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/ranges/range.txt
@@ -0,0 +1 @@
+This should be seen.
diff --git a/netwerk/test/httpserver/test/data/sjs/cgi.sjs b/netwerk/test/httpserver/test/data/sjs/cgi.sjs
new file mode 100644
index 0000000000..a6b987a8b7
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/cgi.sjs
@@ -0,0 +1,8 @@
+function handleRequest(request, response) {
+  if (request.queryString == "throw") {
+    throw new Error("monkey wrench!");
+  }
+
+  response.setHeader("Content-Type", "text/plain", false);
+  response.write("PASS");
+}
diff --git a/netwerk/test/httpserver/test/data/sjs/cgi.sjs^headers^ b/netwerk/test/httpserver/test/data/sjs/cgi.sjs^headers^
new file mode 100644
index 0000000000..a83ff774ab
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/cgi.sjs^headers^
@@ -0,0 +1,2 @@
+HTTP 500 Error
+This-Header: SHOULD NOT APPEAR IN CGI.JSC RESPONSES!
diff --git a/netwerk/test/httpserver/test/data/sjs/object-state.sjs b/netwerk/test/httpserver/test/data/sjs/object-state.sjs
new file mode 100644
index 0000000000..8f027dfedf
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/object-state.sjs
@@ -0,0 +1,74 @@
+function parseQueryString(str) {
+  var paramArray = str.split("&");
+  var regex = /^([^=]+)=(.*)$/;
+  var params = {};
+  for (var i = 0, sz = paramArray.length; i < sz; i++) {
+    var match = regex.exec(paramArray[i]);
+    if (!match) {
+      throw new Error("Bad parameter in queryString!  '" + paramArray[i] + "'");
+    }
+    params[decodeURIComponent(match[1])] = decodeURIComponent(match[2]);
+  }
+
+  return params;
+}
+
+/*
+ * We're relying somewhat dubiously on all data being sent as soon as it's
+ * available at numerous levels (in Necko in the server-side part of the
+ * connection, in the OS's outgoing socket buffer, in the OS's incoming socket
+ * buffer, and in Necko in the client-side part of the connection), but to the
+ * best of my knowledge there's no way to force data flow at all those levels,
+ * so this is the best we can do.
+ */
+function handleRequest(request, response) {
+  response.setHeader("Cache-Control", "no-cache", false);
+
+  /*
+   * NB: A Content-Type header is *necessary* to avoid content-sniffing, which
+   *     will delay onStartRequest past the the point where the entire head of
+   *     the response has been received.
+   */
+  response.setHeader("Content-Type", "text/plain", false);
+
+  var params = parseQueryString(request.queryString);
+
+  switch (params.state) {
+    case "initial":
+      response.processAsync();
+      response.write("do");
+      var state = {
+        QueryInterface: ChromeUtils.generateQI([]),
+        end() {
+          response.write("ne");
+          response.finish();
+        },
+      };
+      state.wrappedJSObject = state;
+      setObjectState("object-state-test", state);
+      getObjectState("object-state-test", function (obj) {
+        if (obj !== state) {
+          response.write("FAIL bad state save");
+          response.finish();
+        }
+      });
+      break;
+
+    case "intermediate":
+      response.write("intermediate");
+      break;
+
+    case "trigger":
+      response.write("trigger");
+      getObjectState("object-state-test", function (obj) {
+        obj.wrappedJSObject.end();
+        setObjectState("object-state-test", null);
+      });
+      break;
+
+    default:
+      response.setStatusLine(request.httpVersion, 500, "Unexpected State");
+      response.write("Bad state: " + params.state);
+      break;
+  }
+}
diff --git a/netwerk/test/httpserver/test/data/sjs/qi.sjs b/netwerk/test/httpserver/test/data/sjs/qi.sjs
new file mode 100644
index 0000000000..ee0fc74a0f
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/qi.sjs
@@ -0,0 +1,45 @@
+function handleRequest(request, response) {
+  var exstr, qid;
+
+  response.setStatusLine(request.httpVersion, 500, "FAIL");
+
+  var passed = false;
+  try {
+    qid = request.QueryInterface(Ci.nsIHttpRequest);
+    passed = qid === request;
+  } catch (e) {
+    // eslint-disable-next-line no-control-regex
+    exstr = ("" + e).split(/[\x09\x20-\x7f\x81-\xff]+/)[0];
+    response.setStatusLine(
+      request.httpVersion,
+      500,
+      "request doesn't QI: " + exstr
+    );
+    return;
+  }
+  if (!passed) {
+    response.setStatusLine(request.httpVersion, 500, "request QI'd wrongly?");
+    return;
+  }
+
+  passed = false;
+  try {
+    qid = response.QueryInterface(Ci.nsIHttpResponse);
+    passed = qid === response;
+  } catch (e) {
+    // eslint-disable-next-line no-control-regex
+    exstr = ("" + e).split(/[\x09\x20-\x7f\x81-\xff]+/)[0];
+    response.setStatusLine(
+      request.httpVersion,
+      500,
+      "response doesn't QI: " + exstr
+    );
+    return;
+  }
+  if (!passed) {
+    response.setStatusLine(request.httpVersion, 500, "response QI'd wrongly?");
+    return;
+  }
+
+  response.setStatusLine(request.httpVersion, 200, "SJS QI Tests Passed");
+}
diff --git a/netwerk/test/httpserver/test/data/sjs/range-checker.sjs b/netwerk/test/httpserver/test/data/sjs/range-checker.sjs
new file mode 100644
index 0000000000..4bc447f739
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/range-checker.sjs
@@ -0,0 +1 @@
+function handleRequest(request, response) {}
diff --git a/netwerk/test/httpserver/test/data/sjs/sjs b/netwerk/test/httpserver/test/data/sjs/sjs
new file mode 100644
index 0000000000..374ca41674
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/sjs
@@ -0,0 +1,4 @@
+function handleRequest(request, response)
+{
+  response.write("FAIL");
+}
diff --git a/netwerk/test/httpserver/test/data/sjs/state1.sjs b/netwerk/test/httpserver/test/data/sjs/state1.sjs
new file mode 100644
index 0000000000..1a2540eca1
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/state1.sjs
@@ -0,0 +1,38 @@
+function parseQueryString(str) {
+  var paramArray = str.split("&");
+  var regex = /^([^=]+)=(.*)$/;
+  var params = {};
+  for (var i = 0, sz = paramArray.length; i < sz; i++) {
+    var match = regex.exec(paramArray[i]);
+    if (!match) {
+      throw new Error("Bad parameter in queryString!  '" + paramArray[i] + "'");
+    }
+    params[decodeURIComponent(match[1])] = decodeURIComponent(match[2]);
+  }
+
+  return params;
+}
+
+function handleRequest(request, response) {
+  response.setHeader("Cache-Control", "no-cache", false);
+
+  var params = parseQueryString(request.queryString);
+
+  var oldShared = getSharedState("shared-value");
+  response.setHeader("X-Old-Shared-Value", oldShared, false);
+
+  var newShared = params.newShared;
+  if (newShared !== undefined) {
+    setSharedState("shared-value", newShared);
+    response.setHeader("X-New-Shared-Value", newShared, false);
+  }
+
+  var oldPrivate = getState("private-value");
+  response.setHeader("X-Old-Private-Value", oldPrivate, false);
+
+  var newPrivate = params.newPrivate;
+  if (newPrivate !== undefined) {
+    setState("private-value", newPrivate);
+    response.setHeader("X-New-Private-Value", newPrivate, false);
+  }
+}
diff --git a/netwerk/test/httpserver/test/data/sjs/state2.sjs b/netwerk/test/httpserver/test/data/sjs/state2.sjs
new file mode 100644
index 0000000000..1a2540eca1
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/state2.sjs
@@ -0,0 +1,38 @@
+function parseQueryString(str) {
+  var paramArray = str.split("&");
+  var regex = /^([^=]+)=(.*)$/;
+  var params = {};
+  for (var i = 0, sz = paramArray.length; i < sz; i++) {
+    var match = regex.exec(paramArray[i]);
+    if (!match) {
+      throw new Error("Bad parameter in queryString!  '" + paramArray[i] + "'");
+    }
+    params[decodeURIComponent(match[1])] = decodeURIComponent(match[2]);
+  }
+
+  return params;
+}
+
+function handleRequest(request, response) {
+  response.setHeader("Cache-Control", "no-cache", false);
+
+  var params = parseQueryString(request.queryString);
+
+  var oldShared = getSharedState("shared-value");
+  response.setHeader("X-Old-Shared-Value", oldShared, false);
+
+  var newShared = params.newShared;
+  if (newShared !== undefined) {
+    setSharedState("shared-value", newShared);
+    response.setHeader("X-New-Shared-Value", newShared, false);
+  }
+
+  var oldPrivate = getState("private-value");
+  response.setHeader("X-Old-Private-Value", oldPrivate, false);
+
+  var newPrivate = params.newPrivate;
+  if (newPrivate !== undefined) {
+    setState("private-value", newPrivate);
+    response.setHeader("X-New-Private-Value", newPrivate, false);
+  }
+}
diff --git a/netwerk/test/httpserver/test/data/sjs/thrower.sjs b/netwerk/test/httpserver/test/data/sjs/thrower.sjs
new file mode 100644
index 0000000000..b34de70e30
--- /dev/null
+++ b/netwerk/test/httpserver/test/data/sjs/thrower.sjs
@@ -0,0 +1,6 @@
+function handleRequest(request, response) {
+  if (request.queryString == "throw") {
+    undefined[5];
+  }
+  response.setHeader("X-Test-Status", "PASS", false);
+}
diff --git a/netwerk/test/httpserver/test/head_utils.js b/netwerk/test/httpserver/test/head_utils.js
new file mode 100644
index 0000000000..3f2fad4940
--- /dev/null
+++ b/netwerk/test/httpserver/test/head_utils.js
@@ -0,0 +1,605 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const {
+  dumpn,
+  LineData,
+  nsHttpHeaders,
+  HttpServer,
+  WriteThroughCopier,
+  overrideBinaryStreamsForTests,
+} = ChromeUtils.importESModule("resource://testing-common/httpd.sys.mjs");
+
+// if these tests fail, we'll want the debug output
+var linDEBUG = true;
+
+var { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+var { NetUtil } = ChromeUtils.importESModule(
+  "resource://gre/modules/NetUtil.sys.mjs"
+);
+
+const CC = Components.Constructor;
+const FileInputStream = CC(
+  "@mozilla.org/network/file-input-stream;1",
+  "nsIFileInputStream",
+  "init"
+);
+var BinaryInputStream = CC(
+  "@mozilla.org/binaryinputstream;1",
+  "nsIBinaryInputStream",
+  "setInputStream"
+);
+var BinaryOutputStream = CC(
+  "@mozilla.org/binaryoutputstream;1",
+  "nsIBinaryOutputStream",
+  "setOutputStream"
+);
+const ScriptableInputStream = CC(
+  "@mozilla.org/scriptableinputstream;1",
+  "nsIScriptableInputStream",
+  "init"
+);
+
+/**
+ * Constructs a new nsHttpServer instance.  This function is intended to
+ * encapsulate construction of a server so that at some point in the future it
+ * is possible to run these tests (with at most slight modifications) against
+ * the server when used as an XPCOM component (not as an inline script).
+ */
+function createServer() {
+  return new HttpServer();
+}
+
+/**
+ * Creates a new HTTP channel.
+ *
+ * @param url
+ *   the URL of the channel to create
+ */
+function makeChannel(url) {
+  return NetUtil.newChannel({
+    uri: url,
+    loadUsingSystemPrincipal: true,
+  }).QueryInterface(Ci.nsIHttpChannel);
+}
+
+/**
+ * Make a binary input stream wrapper for the given stream.
+ *
+ * @param stream
+ *   the nsIInputStream to wrap
+ */
+function makeBIS(stream) {
+  return new BinaryInputStream(stream);
+}
+
+/**
+ * Returns the contents of the file as a string.
+ *
+ * @param file : nsIFile
+ *   the file whose contents are to be read
+ * @returns string
+ *   the contents of the file
+ */
+function fileContents(file) {
+  const PR_RDONLY = 0x01;
+  var fis = new FileInputStream(
+    file,
+    PR_RDONLY,
+    0o444,
+    Ci.nsIFileInputStream.CLOSE_ON_EOF
+  );
+  var sis = new ScriptableInputStream(fis);
+  var contents = sis.read(file.fileSize);
+  sis.close();
+  return contents;
+}
+
+/**
+ * Iterates over the lines, delimited by CRLF, in data, returning each line
+ * without the trailing line separator.
+ *
+ * @param data : string
+ *   a string consisting of lines of data separated by CRLFs
+ * @returns Iterator
+ *   an Iterator which returns each line from data in turn; note that this
+ *   includes a final empty line if data ended with a CRLF
+ */
+function* LineIterator(data) {
+  var index = 0;
+  do {
+    index = data.indexOf("\r\n");
+    if (index >= 0) {
+      yield data.substring(0, index);
+    } else {
+      yield data;
+    }
+
+    data = data.substring(index + 2);
+  } while (index >= 0);
+}
+
+/**
+ * Throws if iter does not contain exactly the CRLF-separated lines in the
+ * array expectedLines.
+ *
+ * @param iter : Iterator
+ *   an Iterator which returns lines of text
+ * @param expectedLines : [string]
+ *   an array of the expected lines of text
+ * @throws an error message if iter doesn't agree with expectedLines
+ */
+function expectLines(iter, expectedLines) {
+  var index = 0;
+  for (var line of iter) {
+    if (expectedLines.length == index) {
+      throw new Error(
+        `Error: got more than ${expectedLines.length} expected lines!`
+      );
+    }
+
+    var expected = expectedLines[index++];
+    if (expected !== line) {
+      throw new Error(`Error on line ${index}!
+  actual: '${line}',
+  expect: '${expected}'`);
+    }
+  }
+
+  if (expectedLines.length !== index) {
+    throw new Error(
+      `Expected more lines!  Got ${index}, expected ${expectedLines.length}`
+    );
+  }
+}
+
+/**
+ * Spew a bunch of HTTP metadata from request into the body of response.
+ *
+ * @param request : nsIHttpRequest
+ *   the request whose metadata should be output
+ * @param response : nsIHttpResponse
+ *   the response to which the metadata is written
+ */
+function writeDetails(request, response) {
+  response.write("Method:  " + request.method + "\r\n");
+  response.write("Path:    " + request.path + "\r\n");
+  response.write("Query:   " + request.queryString + "\r\n");
+  response.write("Version: " + request.httpVersion + "\r\n");
+  response.write("Scheme:  " + request.scheme + "\r\n");
+  response.write("Host:    " + request.host + "\r\n");
+  response.write("Port:    " + request.port);
+}
+
+/**
+ * Advances iter past all non-blank lines and a single blank line, after which
+ * point the body of the response will be returned next from the iterator.
+ *
+ * @param iter : Iterator
+ *   an iterator over the CRLF-delimited lines in an HTTP response, currently
+ *   just after the Request-Line
+ */
+function skipHeaders(iter) {
+  var line = iter.next().value;
+  while (line !== "") {
+    line = iter.next().value;
+  }
+}
+
+/**
+ * Checks that the exception e (which may be an XPConnect-created exception
+ * object or a raw nsresult number) is the given nsresult.
+ *
+ * @param e : Exception or nsresult
+ *   the actual exception
+ * @param code : nsresult
+ *   the expected exception
+ */
+function isException(e, code) {
+  if (e !== code && e.result !== code) {
+    do_throw("unexpected error: " + e);
+  }
+}
+
+/**
+ * Calls the given function at least the specified number of milliseconds later.
+ * The callback will not undershoot the given time, but it might overshoot --
+ * don't expect precision!
+ *
+ * @param milliseconds : uint
+ *   the number of milliseconds to delay
+ * @param callback : function() : void
+ *   the function to call
+ */
+function callLater(msecs, callback) {
+  do_timeout(msecs, callback);
+}
+
+/** *****************************************************
+ * SIMPLE SUPPORT FOR LOADING/TESTING A SERIES OF URLS *
+ *******************************************************/
+
+/**
+ * Create a completion callback which will stop the given server and end the
+ * test, assuming nothing else remains to be done at that point.
+ */
+function testComplete(srv) {
+  return function complete() {
+    do_test_pending();
+    srv.stop(function quit() {
+      do_test_finished();
+    });
+  };
+}
+
+/**
+ * Represents a path to load from the tested HTTP server, along with actions to
+ * take before, during, and after loading the associated page.
+ *
+ * @param path
+ *   the URL to load from the server
+ * @param initChannel
+ *   a function which takes as a single parameter a channel created for path and
+ *   initializes its state, or null if no additional initialization is needed
+ * @param onStartRequest
+ *   called during onStartRequest for the load of the URL, with the same
+ *   parameters; the request parameter has been QI'd to nsIHttpChannel and
+ *   nsIHttpChannelInternal for convenience; may be null if nothing needs to be
+ *   done
+ * @param onStopRequest
+ *   called during onStopRequest for the channel, with the same parameters plus
+ *   a trailing parameter containing an array of the bytes of data downloaded in
+ *   the body of the channel response; the request parameter has been QI'd to
+ *   nsIHttpChannel and nsIHttpChannelInternal for convenience; may be null if
+ *   nothing needs to be done
+ */
+function Test(path, initChannel, onStartRequest, onStopRequest) {
+  function nil() {}
+
+  this.path = path;
+  this.initChannel = initChannel || nil;
+  this.onStartRequest = onStartRequest || nil;
+  this.onStopRequest = onStopRequest || nil;
+}
+
+/**
+ * Runs all the tests in testArray.
+ *
+ * @param testArray
+ *   a non-empty array of Tests to run, in order
+ * @param done
+ *   function to call when all tests have run (e.g. to shut down the server)
+ */
+function runHttpTests(testArray, done) {
+  /** Kicks off running the next test in the array. */
+  function performNextTest() {
+    if (++testIndex == testArray.length) {
+      try {
+        done();
+      } catch (e) {
+        do_report_unexpected_exception(e, "running test-completion callback");
+      }
+      return;
+    }
+
+    do_test_pending();
+
+    var test = testArray[testIndex];
+    var ch = makeChannel(test.path);
+    try {
+      test.initChannel(ch);
+    } catch (e) {
+      try {
+        do_report_unexpected_exception(
+          e,
+          "testArray[" + testIndex + "].initChannel(ch)"
+        );
+      } catch (x) {
+        /* swallow and let tests continue */
+      }
+    }
+
+    listener._channel = ch;
+    ch.asyncOpen(listener);
+  }
+
+  /** Index of the test being run. */
+  var testIndex = -1;
+
+  /** Stream listener for the channels. */
+  var listener = {
+    /** Current channel being observed by this. */
+    _channel: null,
+    /** Array of bytes of data in body of response. */
+    _data: [],
+
+    onStartRequest(request) {
+      Assert.ok(request === this._channel);
+      var ch = request
+        .QueryInterface(Ci.nsIHttpChannel)
+        .QueryInterface(Ci.nsIHttpChannelInternal);
+
+      this._data.length = 0;
+      try {
+        try {
+          testArray[testIndex].onStartRequest(ch);
+        } catch (e) {
+          do_report_unexpected_exception(
+            e,
+            "testArray[" + testIndex + "].onStartRequest"
+          );
+        }
+      } catch (e) {
+        do_note_exception(
+          e,
+          "!!! swallowing onStartRequest exception so onStopRequest is " +
+            "called..."
+        );
+      }
+    },
+    onDataAvailable(request, inputStream, offset, count) {
+      var quantum = 262144; // just above half the argument-count limit
+      var bis = makeBIS(inputStream);
+      for (var start = 0; start < count; start += quantum) {
+        var newData = bis.readByteArray(Math.min(quantum, count - start));
+        Array.prototype.push.apply(this._data, newData);
+      }
+    },
+    onStopRequest(request, status) {
+      this._channel = null;
+
+      var ch = request
+        .QueryInterface(Ci.nsIHttpChannel)
+        .QueryInterface(Ci.nsIHttpChannelInternal);
+
+      // NB: The onStopRequest callback must run before performNextTest here,
+      //     because the latter runs the next test's initChannel callback, and
+      //     we want one test to be sequentially processed before the next
+      //     one.
+      try {
+        testArray[testIndex].onStopRequest(ch, status, this._data);
+      } catch (e) {
+        do_report_unexpected_exception(
+          e,
+          "testArray[" + testIndex + "].onStartRequest"
+        );
+      } finally {
+        try {
+          performNextTest();
+        } finally {
+          do_test_finished();
+        }
+      }
+    },
+    QueryInterface: ChromeUtils.generateQI([
+      "nsIStreamListener",
+      "nsIRequestObserver",
+    ]),
+  };
+
+  performNextTest();
+}
+
+/** **************************************
+ * RAW REQUEST FORMAT TESTING FUNCTIONS *
+ ****************************************/
+
+/**
+ * Sends a raw string of bytes to the given host and port and checks that the
+ * response is acceptable.
+ *
+ * @param host : string
+ *   the host to which a connection should be made
+ * @param port : PRUint16
+ *   the port to use for the connection
+ * @param data : string or [string...]
+ *   either:
+ *     - the raw data to send, as a string of characters with codes in the
+ *       range 0-255, or
+ *     - an array of such strings whose concatenation forms the raw data
+ * @param responseCheck : function(string) : void
+ *   a function which is provided with the data sent by the remote host which
+ *   conducts whatever tests it wants on that data; useful for tweaking the test
+ *   environment between tests
+ */
+function RawTest(host, port, data, responseCheck) {
+  if (0 > port || 65535 < port || port % 1 !== 0) {
+    throw new Error("bad port");
+  }
+  if (!(data instanceof Array)) {
+    data = [data];
+  }
+  if (data.length <= 0) {
+    throw new Error("bad data length");
+  }
+
+  if (
+    !data.every(function (v) {
+      // eslint-disable-next-line no-control-regex
+      return /^[\x00-\xff]*$/.test(v);
+    })
+  ) {
+    throw new Error("bad data contained non-byte-valued character");
+  }
+
+  this.host = host;
+  this.port = port;
+  this.data = data;
+  this.responseCheck = responseCheck;
+}
+
+/**
+ * Runs all the tests in testArray, an array of RawTests.
+ *
+ * @param testArray : [RawTest]
+ *   an array of RawTests to run, in order
+ * @param done
+ *   function to call when all tests have run (e.g. to shut down the server)
+ * @param beforeTestCallback
+ *   function to call before each test is run. Gets passed testIndex when called
+ */
+function runRawTests(testArray, done, beforeTestCallback) {
+  do_test_pending();
+
+  var sts = Cc["@mozilla.org/network/socket-transport-service;1"].getService(
+    Ci.nsISocketTransportService
+  );
+
+  var currentThread =
+    Cc["@mozilla.org/thread-manager;1"].getService().currentThread;
+
+  /** Kicks off running the next test in the array. */
+  function performNextTest() {
+    if (++testIndex == testArray.length) {
+      do_test_finished();
+      try {
+        done();
+      } catch (e) {
+        do_report_unexpected_exception(e, "running test-completion callback");
+      }
+      return;
+    }
+
+    if (beforeTestCallback) {
+      try {
+        beforeTestCallback(testIndex);
+      } catch (e) {
+        /* We don't care if this call fails */
+      }
+    }
+
+    var rawTest = testArray[testIndex];
+
+    var transport = sts.createTransport(
+      [],
+      rawTest.host,
+      rawTest.port,
+      null,
+      null
+    );
+
+    var inStream = transport.openInputStream(0, 0, 0);
+    var outStream = transport.openOutputStream(0, 0, 0);
+
+    // reset
+    dataIndex = 0;
+    received = "";
+
+    waitForMoreInput(inStream);
+    waitToWriteOutput(outStream);
+  }
+
+  function waitForMoreInput(stream) {
+    reader.stream = stream;
+    stream = stream.QueryInterface(Ci.nsIAsyncInputStream);
+    stream.asyncWait(reader, 0, 0, currentThread);
+  }
+
+  function waitToWriteOutput(stream) {
+    // Do the QueryInterface here, not earlier, because there is no
+    // guarantee that 'stream' passed in here been QIed to nsIAsyncOutputStream
+    // since the last GC.
+    stream = stream.QueryInterface(Ci.nsIAsyncOutputStream);
+    stream.asyncWait(
+      writer,
+      0,
+      testArray[testIndex].data[dataIndex].length,
+      currentThread
+    );
+  }
+
+  /** Index of the test being run. */
+  var testIndex = -1;
+
+  /**
+   * Index of remaining data strings to be written to the socket in current
+   * test.
+   */
+  var dataIndex = 0;
+
+  /** Data received so far from the server. */
+  var received = "";
+
+  /** Reads data from the socket. */
+  var reader = {
+    onInputStreamReady(stream) {
+      Assert.ok(stream === this.stream);
+      try {
+        var bis = new BinaryInputStream(stream);
+
+        var av = 0;
+        try {
+          av = bis.available();
+        } catch (e) {
+          /* default to 0 */
+          do_note_exception(e);
+        }
+
+        if (av > 0) {
+          var quantum = 262144;
+          for (var start = 0; start < av; start += quantum) {
+            var bytes = bis.readByteArray(Math.min(quantum, av - start));
+            received += String.fromCharCode.apply(null, bytes);
+          }
+          waitForMoreInput(stream);
+          return;
+        }
+      } catch (e) {
+        do_report_unexpected_exception(e);
+      }
+
+      var rawTest = testArray[testIndex];
+      try {
+        rawTest.responseCheck(received);
+      } catch (e) {
+        do_report_unexpected_exception(e);
+      } finally {
+        try {
+          stream.close();
+          performNextTest();
+        } catch (e) {
+          do_report_unexpected_exception(e);
+        }
+      }
+    },
+  };
+
+  /** Writes data to the socket. */
+  var writer = {
+    onOutputStreamReady(stream) {
+      var str = testArray[testIndex].data[dataIndex];
+
+      var written = 0;
+      try {
+        written = stream.write(str, str.length);
+        if (written == str.length) {
+          dataIndex++;
+        } else {
+          testArray[testIndex].data[dataIndex] = str.substring(written);
+        }
+      } catch (e) {
+        do_note_exception(e);
+        /* stream could have been closed, just ignore */
+      }
+
+      try {
+        // Keep writing data while we can write and
+        // until there's no more data to read
+        if (written > 0 && dataIndex < testArray[testIndex].data.length) {
+          waitToWriteOutput(stream);
+        } else {
+          stream.close();
+        }
+      } catch (e) {
+        do_report_unexpected_exception(e);
+      }
+    },
+  };
+
+  performNextTest();
+}
diff --git a/netwerk/test/httpserver/test/test_async_response_sending.js b/netwerk/test/httpserver/test/test_async_response_sending.js
new file mode 100644
index 0000000000..bc025308ae
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_async_response_sending.js
@@ -0,0 +1,1661 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Ensures that data a request handler writes out in response is sent only as
+ * quickly as the client can receive it, without racing ahead and being forced
+ * to block while writing that data.
+ *
+ * NB: These tests are extremely tied to the current implementation, in terms of
+ * when and how stream-ready notifications occur, the amount of data which will
+ * be read or written at each notification, and so on.  If the implementation
+ * changes in any way with respect to stream copying, this test will probably
+ * have to change a little at the edges as well.
+ */
+
+function run_test() {
+  do_test_pending();
+  tests.push(function testsComplete(_) {
+    dumpn(
+      // eslint-disable-next-line no-useless-concat
+      "******************\n" + "* TESTS COMPLETE *\n" + "******************"
+    );
+    do_test_finished();
+  });
+
+  runNextTest();
+}
+
+function runNextTest() {
+  testIndex++;
+  dumpn("*** runNextTest(), testIndex: " + testIndex);
+
+  try {
+    var test = tests[testIndex];
+    test(runNextTest);
+  } catch (e) {
+    var msg = "exception running test " + testIndex + ": " + e;
+    if (e && "stack" in e) {
+      msg += "\nstack follows:\n" + e.stack;
+    }
+    do_throw(msg);
+  }
+}
+
+/** ***********
+ * TEST DATA *
+ *************/
+
+const NOTHING = [];
+
+const FIRST_SEGMENT = [1, 2, 3, 4];
+const SECOND_SEGMENT = [5, 6, 7, 8];
+const THIRD_SEGMENT = [9, 10, 11, 12];
+
+const SEGMENT = FIRST_SEGMENT;
+const TWO_SEGMENTS = [1, 2, 3, 4, 5, 6, 7, 8];
+const THREE_SEGMENTS = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12];
+
+const SEGMENT_AND_HALF = [1, 2, 3, 4, 5, 6];
+
+const QUARTER_SEGMENT = [1];
+const HALF_SEGMENT = [1, 2];
+const SECOND_HALF_SEGMENT = [3, 4];
+const EXTRA_HALF_SEGMENT = [5, 6];
+const MIDDLE_HALF_SEGMENT = [2, 3];
+const LAST_QUARTER_SEGMENT = [4];
+const HALF_THIRD_SEGMENT = [9, 10];
+const LATTER_HALF_THIRD_SEGMENT = [11, 12];
+
+const TWO_HALF_SEGMENTS = [1, 2, 1, 2];
+
+/** *******
+ * TESTS *
+ *********/
+
+var tests = [
+  sourceClosedWithoutWrite,
+  writeOneSegmentThenClose,
+  simpleWriteThenRead,
+  writeLittleBeforeReading,
+  writeMultipleSegmentsThenRead,
+  writeLotsBeforeReading,
+  writeLotsBeforeReading2,
+  writeThenReadPartial,
+  manyPartialWrites,
+  partialRead,
+  partialWrite,
+  sinkClosedImmediately,
+  sinkClosedWithReadableData,
+  sinkClosedAfterWrite,
+  sourceAndSinkClosed,
+  sinkAndSourceClosed,
+  sourceAndSinkClosedWithPendingData,
+  sinkAndSourceClosedWithPendingData,
+];
+var testIndex = -1;
+
+function sourceClosedWithoutWrite(next) {
+  var t = new CopyTest("sourceClosedWithoutWrite", next);
+
+  t.closeSource(Cr.NS_OK);
+  t.expect(Cr.NS_OK, [NOTHING]);
+}
+
+function writeOneSegmentThenClose(next) {
+  var t = new CopyTest("writeLittleBeforeReading", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.closeSource(Cr.NS_OK);
+  t.makeSinkWritableAndWaitFor(SEGMENT.length, [SEGMENT]);
+  t.expect(Cr.NS_OK, [SEGMENT]);
+}
+
+function simpleWriteThenRead(next) {
+  var t = new CopyTest("simpleWriteThenRead", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.makeSinkWritableAndWaitFor(SEGMENT.length, [SEGMENT]);
+  t.closeSource(Cr.NS_OK);
+  t.expect(Cr.NS_OK, [SEGMENT]);
+}
+
+function writeLittleBeforeReading(next) {
+  var t = new CopyTest("writeLittleBeforeReading", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.closeSource(Cr.NS_OK);
+  t.makeSinkWritableAndWaitFor(SEGMENT.length, [SEGMENT]);
+  t.makeSinkWritableAndWaitFor(SEGMENT.length, [SEGMENT]);
+  t.expect(Cr.NS_OK, [SEGMENT, SEGMENT]);
+}
+
+function writeMultipleSegmentsThenRead(next) {
+  var t = new CopyTest("writeMultipleSegmentsThenRead", next);
+
+  t.addToSource(TWO_SEGMENTS);
+  t.makeSourceReadable(TWO_SEGMENTS.length);
+  t.makeSinkWritableAndWaitFor(TWO_SEGMENTS.length, [
+    FIRST_SEGMENT,
+    SECOND_SEGMENT,
+  ]);
+  t.closeSource(Cr.NS_OK);
+  t.expect(Cr.NS_OK, [TWO_SEGMENTS]);
+}
+
+function writeLotsBeforeReading(next) {
+  var t = new CopyTest("writeLotsBeforeReading", next);
+
+  t.addToSource(TWO_SEGMENTS);
+  t.makeSourceReadable(TWO_SEGMENTS.length);
+  t.makeSinkWritableAndWaitFor(FIRST_SEGMENT.length, [FIRST_SEGMENT]);
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.makeSinkWritableAndWaitFor(SECOND_SEGMENT.length, [SECOND_SEGMENT]);
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.closeSource(Cr.NS_OK);
+  t.makeSinkWritableAndWaitFor(2 * SEGMENT.length, [SEGMENT, SEGMENT]);
+  t.expect(Cr.NS_OK, [TWO_SEGMENTS, SEGMENT, SEGMENT]);
+}
+
+function writeLotsBeforeReading2(next) {
+  var t = new CopyTest("writeLotsBeforeReading", next);
+
+  t.addToSource(THREE_SEGMENTS);
+  t.makeSourceReadable(THREE_SEGMENTS.length);
+  t.makeSinkWritableAndWaitFor(FIRST_SEGMENT.length, [FIRST_SEGMENT]);
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.makeSinkWritableAndWaitFor(SECOND_SEGMENT.length, [SECOND_SEGMENT]);
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.makeSinkWritableAndWaitFor(THIRD_SEGMENT.length, [THIRD_SEGMENT]);
+  t.closeSource(Cr.NS_OK);
+  t.makeSinkWritableAndWaitFor(2 * SEGMENT.length, [SEGMENT, SEGMENT]);
+  t.expect(Cr.NS_OK, [THREE_SEGMENTS, SEGMENT, SEGMENT]);
+}
+
+function writeThenReadPartial(next) {
+  var t = new CopyTest("writeThenReadPartial", next);
+
+  t.addToSource(SEGMENT_AND_HALF);
+  t.makeSourceReadable(SEGMENT_AND_HALF.length);
+  t.makeSinkWritableAndWaitFor(SEGMENT.length, [SEGMENT]);
+  t.closeSource(Cr.NS_OK);
+  t.makeSinkWritableAndWaitFor(EXTRA_HALF_SEGMENT.length, [EXTRA_HALF_SEGMENT]);
+  t.expect(Cr.NS_OK, [SEGMENT_AND_HALF]);
+}
+
+function manyPartialWrites(next) {
+  var t = new CopyTest("manyPartialWrites", next);
+
+  t.addToSource(HALF_SEGMENT);
+  t.makeSourceReadable(HALF_SEGMENT.length);
+
+  t.addToSource(HALF_SEGMENT);
+  t.makeSourceReadable(HALF_SEGMENT.length);
+  t.makeSinkWritableAndWaitFor(2 * HALF_SEGMENT.length, [TWO_HALF_SEGMENTS]);
+  t.closeSource(Cr.NS_OK);
+  t.expect(Cr.NS_OK, [TWO_HALF_SEGMENTS]);
+}
+
+function partialRead(next) {
+  var t = new CopyTest("partialRead", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.addToSource(HALF_SEGMENT);
+  t.makeSourceReadable(HALF_SEGMENT.length);
+  t.makeSinkWritableAndWaitFor(SEGMENT.length, [SEGMENT]);
+  t.closeSourceAndWaitFor(Cr.NS_OK, HALF_SEGMENT.length, [HALF_SEGMENT]);
+  t.expect(Cr.NS_OK, [SEGMENT, HALF_SEGMENT]);
+}
+
+function partialWrite(next) {
+  var t = new CopyTest("partialWrite", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.makeSinkWritableByIncrementsAndWaitFor(SEGMENT.length, [
+    QUARTER_SEGMENT,
+    MIDDLE_HALF_SEGMENT,
+    LAST_QUARTER_SEGMENT,
+  ]);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.makeSinkWritableByIncrementsAndWaitFor(SEGMENT.length, [
+    HALF_SEGMENT,
+    SECOND_HALF_SEGMENT,
+  ]);
+
+  t.addToSource(THREE_SEGMENTS);
+  t.makeSourceReadable(THREE_SEGMENTS.length);
+  t.makeSinkWritableByIncrementsAndWaitFor(THREE_SEGMENTS.length, [
+    HALF_SEGMENT,
+    SECOND_HALF_SEGMENT,
+    SECOND_SEGMENT,
+    HALF_THIRD_SEGMENT,
+    LATTER_HALF_THIRD_SEGMENT,
+  ]);
+
+  t.closeSource(Cr.NS_OK);
+  t.expect(Cr.NS_OK, [SEGMENT, SEGMENT, THREE_SEGMENTS]);
+}
+
+function sinkClosedImmediately(next) {
+  var t = new CopyTest("sinkClosedImmediately", next);
+
+  t.closeSink(Cr.NS_OK);
+  t.expect(Cr.NS_ERROR_UNEXPECTED, [NOTHING]);
+}
+
+function sinkClosedWithReadableData(next) {
+  var t = new CopyTest("sinkClosedWithReadableData", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+  t.closeSink(Cr.NS_OK);
+  t.expect(Cr.NS_ERROR_UNEXPECTED, [NOTHING]);
+}
+
+function sinkClosedAfterWrite(next) {
+  var t = new CopyTest("sinkClosedAfterWrite", next);
+
+  t.addToSource(TWO_SEGMENTS);
+  t.makeSourceReadable(TWO_SEGMENTS.length);
+  t.makeSinkWritableAndWaitFor(FIRST_SEGMENT.length, [FIRST_SEGMENT]);
+  t.closeSink(Cr.NS_OK);
+  t.expect(Cr.NS_ERROR_UNEXPECTED, [FIRST_SEGMENT]);
+}
+
+function sourceAndSinkClosed(next) {
+  var t = new CopyTest("sourceAndSinkClosed", next);
+
+  t.closeSourceThenSink(Cr.NS_OK, Cr.NS_OK);
+  t.expect(Cr.NS_OK, []);
+}
+
+function sinkAndSourceClosed(next) {
+  var t = new CopyTest("sinkAndSourceClosed", next);
+
+  t.closeSinkThenSource(Cr.NS_OK, Cr.NS_OK);
+
+  // sink notify received first, hence error
+  t.expect(Cr.NS_ERROR_UNEXPECTED, []);
+}
+
+function sourceAndSinkClosedWithPendingData(next) {
+  var t = new CopyTest("sourceAndSinkClosedWithPendingData", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+
+  t.closeSourceThenSink(Cr.NS_OK, Cr.NS_OK);
+
+  // not all data from source copied, so error
+  t.expect(Cr.NS_ERROR_UNEXPECTED, []);
+}
+
+function sinkAndSourceClosedWithPendingData(next) {
+  var t = new CopyTest("sinkAndSourceClosedWithPendingData", next);
+
+  t.addToSource(SEGMENT);
+  t.makeSourceReadable(SEGMENT.length);
+
+  t.closeSinkThenSource(Cr.NS_OK, Cr.NS_OK);
+
+  // not all data from source copied, plus sink notify received first, so error
+  t.expect(Cr.NS_ERROR_UNEXPECTED, []);
+}
+
+/** ***********
+ * UTILITIES *
+ *************/
+
+/** Returns the sum of the elements in arr. */
+function sum(arr) {
+  var s = 0;
+  for (var i = 0, sz = arr.length; i < sz; i++) {
+    s += arr[i];
+  }
+  return s;
+}
+
+/**
+ * Returns a constructor for an input or output stream callback that will wrap
+ * the one provided to it as an argument.
+ *
+ * @param wrapperCallback : (nsIInputStreamCallback | nsIOutputStreamCallback) : void
+ *   the original callback object (not a function!) being wrapped
+ * @param name : string
+ *   either "onInputStreamReady" if we're wrapping an input stream callback or
+ *   "onOutputStreamReady" if we're wrapping an output stream callback
+ * @returns function(nsIInputStreamCallback | nsIOutputStreamCallback) : (nsIInputStreamCallback | nsIOutputStreamCallback)
+ *   a constructor function which constructs a callback object (not function!)
+ *   which, when called, first calls the original callback provided to it and
+ *   then calls wrapperCallback
+ */
+function createStreamReadyInterceptor(wrapperCallback, name) {
+  return function StreamReadyInterceptor(callback) {
+    this.wrappedCallback = callback;
+    this[name] = function streamReadyInterceptor(stream) {
+      dumpn("*** StreamReadyInterceptor." + name);
+
+      try {
+        dumpn("*** calling original " + name + "...");
+        callback[name](stream);
+      } catch (e) {
+        dumpn("!!! error running inner callback: " + e);
+        throw e;
+      } finally {
+        dumpn("*** calling wrapper " + name + "...");
+        wrapperCallback[name](stream);
+      }
+    };
+  };
+}
+
+/**
+ * Print out a banner with the given message, uppercased, for debugging
+ * purposes.
+ */
+function note(m) {
+  m = m.toUpperCase();
+  var asterisks = Array(m.length + 1 + 4).join("*");
+  dumpn(asterisks + "\n* " + m + " *\n" + asterisks);
+}
+
+/** *********
+ * MOCKERY *
+ ***********/
+
+/*
+ * Blatantly violate abstractions in the name of testability.  THIS IS NOT
+ * PUBLIC API!  If you use any of these I will knowingly break your code by
+ * changing the names of variables and properties.
+ */
+// These are used in head.js.
+BinaryInputStream = function BIS(stream) {
+  return stream;
+};
+BinaryOutputStream = function BOS(stream) {
+  return stream;
+};
+Response.SEGMENT_SIZE = SEGMENT.length;
+// This overrides in httpd.js.
+overrideBinaryStreamsForTests(
+  BinaryInputStream,
+  BinaryOutputStream,
+  SEGMENT.length
+);
+
+/**
+ * Roughly mocks an nsIPipe, presenting non-blocking input and output streams
+ * that appear to also be binary streams and whose readability and writability
+ * amounts are configurable.  Only the methods used in this test have been
+ * implemented -- these aren't exact mocks (can't be, actually, because input
+ * streams have unscriptable methods).
+ *
+ * @param name : string
+ *   a name for this pipe, used in debugging output
+ */
+function CustomPipe(name) {
+  var self = this;
+
+  /** Data read from input that's buffered until it can be written to output. */
+  this._data = [];
+
+  /**
+   * The status of this pipe, which is to say the error result the ends of this
+   * pipe will return when attempts are made to use them.  This value is always
+   * an error result when copying has finished, because success codes are
+   * converted to NS_BASE_STREAM_CLOSED.
+   */
+  this._status = Cr.NS_OK;
+
+  /** The input end of this pipe. */
+  var input = (this.inputStream = {
+    /** A name for this stream, used in debugging output. */
+    name: name + " input",
+
+    /**
+     * The number of bytes of data available to be read from this pipe, or
+     * Infinity if any amount of data in this pipe is made readable as soon as
+     * it is written to the pipe output.
+     */
+    _readable: 0,
+
+    /**
+     * Data regarding a pending stream-ready callback on this, or null if no
+     * callback is currently waiting to be called.
+     */
+    _waiter: null,
+
+    /**
+     * The event currently dispatched to make a stream-ready callback, if any
+     * such callback is currently ready to be made and not already in
+     * progress, or null when no callback is waiting to happen.
+     */
+    _event: null,
+
+    /**
+     * A stream-ready constructor to wrap an existing callback to intercept
+     * stream-ready notifications, or null if notifications shouldn't be
+     * wrapped at all.
+     */
+    _streamReadyInterceptCreator: null,
+
+    /**
+     * Registers a stream-ready wrapper creator function so that a
+     * stream-ready callback made in the future can be wrapped.
+     */
+    interceptStreamReadyCallbacks(streamReadyInterceptCreator) {
+      dumpn("*** [" + this.name + "].interceptStreamReadyCallbacks");
+
+      Assert.ok(
+        this._streamReadyInterceptCreator === null,
+        "intercepting twice"
+      );
+      this._streamReadyInterceptCreator = streamReadyInterceptCreator;
+      if (this._waiter) {
+        this._waiter.callback = new streamReadyInterceptCreator(
+          this._waiter.callback
+        );
+      }
+    },
+
+    /**
+     * Removes a previously-registered stream-ready wrapper creator function,
+     * also clearing any current wrapping.
+     */
+    removeStreamReadyInterceptor() {
+      dumpn("*** [" + this.name + "].removeStreamReadyInterceptor()");
+
+      Assert.ok(
+        this._streamReadyInterceptCreator !== null,
+        "removing interceptor when none present?"
+      );
+      this._streamReadyInterceptCreator = null;
+      if (this._waiter) {
+        this._waiter.callback = this._waiter.callback.wrappedCallback;
+      }
+    },
+
+    //
+    // see nsIAsyncInputStream.asyncWait
+    //
+    asyncWait: function asyncWait(callback, flags, requestedCount, target) {
+      dumpn("*** [" + this.name + "].asyncWait");
+
+      Assert.ok(callback && typeof callback !== "function");
+
+      var closureOnly =
+        (flags & Ci.nsIAsyncInputStream.WAIT_CLOSURE_ONLY) !== 0;
+
+      Assert.ok(
+        this._waiter === null || (this._waiter.closureOnly && !closureOnly),
+        "asyncWait already called with a non-closure-only " +
+          "callback?  unexpected!"
+      );
+
+      this._waiter = {
+        callback: this._streamReadyInterceptCreator
+          ? new this._streamReadyInterceptCreator(callback)
+          : callback,
+        closureOnly,
+        requestedCount,
+        eventTarget: target,
+      };
+
+      if (
+        !Components.isSuccessCode(self._status) ||
+        (!closureOnly &&
+          this._readable >= requestedCount &&
+          self._data.length >= requestedCount)
+      ) {
+        this._notify();
+      }
+    },
+
+    //
+    // see nsIAsyncInputStream.closeWithStatus
+    //
+    closeWithStatus: function closeWithStatus(status) {
+      // eslint-disable-next-line no-useless-concat
+      dumpn("*** [" + this.name + "].closeWithStatus" + "(" + status + ")");
+
+      if (!Components.isSuccessCode(self._status)) {
+        dumpn(
+          "*** ignoring second closure of [input " +
+            this.name +
+            "] " +
+            "(status " +
+            self._status +
+            ")"
+        );
+        return;
+      }
+
+      if (Components.isSuccessCode(status)) {
+        status = Cr.NS_BASE_STREAM_CLOSED;
+      }
+
+      self._status = status;
+
+      if (this._waiter) {
+        this._notify();
+      }
+      if (output._waiter) {
+        output._notify();
+      }
+    },
+
+    //
+    // see nsIBinaryInputStream.readByteArray
+    //
+    readByteArray: function readByteArray(count) {
+      dumpn("*** [" + this.name + "].readByteArray(" + count + ")");
+
+      if (self._data.length === 0) {
+        throw Components.isSuccessCode(self._status)
+          ? Cr.NS_BASE_STREAM_WOULD_BLOCK
+          : self._status;
+      }
+
+      Assert.ok(
+        this._readable <= self._data.length || this._readable === Infinity,
+        "consistency check"
+      );
+
+      if (this._readable < count || self._data.length < count) {
+        throw Components.Exception("", Cr.NS_BASE_STREAM_WOULD_BLOCK);
+      }
+      this._readable -= count;
+      return self._data.splice(0, count);
+    },
+
+    /**
+     * Makes the given number of additional bytes of data previously written
+     * to the pipe's output stream available for reading, triggering future
+     * notifications when required.
+     *
+     * @param count : uint
+     *   the number of bytes of additional data to make available; must not be
+     *   greater than the number of bytes already buffered but not made
+     *   available by previous makeReadable calls
+     */
+    makeReadable: function makeReadable(count) {
+      dumpn("*** [" + this.name + "].makeReadable(" + count + ")");
+
+      Assert.ok(Components.isSuccessCode(self._status), "errant call");
+      Assert.ok(
+        this._readable + count <= self._data.length ||
+          this._readable === Infinity,
+        "increasing readable beyond written amount"
+      );
+
+      this._readable += count;
+
+      dumpn("readable: " + this._readable + ", data: " + self._data);
+
+      var waiter = this._waiter;
+      if (waiter !== null) {
+        if (waiter.requestedCount <= this._readable && !waiter.closureOnly) {
+          this._notify();
+        }
+      }
+    },
+
+    /**
+     * Disables the readability limit on this stream, meaning that as soon as
+     * *any* amount of data is written to output it becomes available from
+     * this stream and a stream-ready event is dispatched (if any stream-ready
+     * callback is currently set).
+     */
+    disableReadabilityLimit: function disableReadabilityLimit() {
+      dumpn("*** [" + this.name + "].disableReadabilityLimit()");
+
+      this._readable = Infinity;
+    },
+
+    //
+    // see nsIInputStream.available
+    //
+    available: function available() {
+      dumpn("*** [" + this.name + "].available()");
+
+      if (self._data.length === 0 && !Components.isSuccessCode(self._status)) {
+        throw self._status;
+      }
+
+      return Math.min(this._readable, self._data.length);
+    },
+
+    /**
+     * Dispatches a pending stream-ready event ahead of schedule, rather than
+     * waiting for it to be dispatched in response to normal writes.  This is
+     * useful when writing to the output has completed, and we need to have
+     * read all data written to this stream.  If the output isn't closed and
+     * the reading of data from this races ahead of the last write to output,
+     * we need a notification to know when everything that's been written has
+     * been read.  This ordinarily might be supplied by closing output, but
+     * in some cases it's not desirable to close output, so this supplies an
+     * alternative method to get notified when the last write has occurred.
+     */
+    maybeNotifyFinally: function maybeNotifyFinally() {
+      dumpn("*** [" + this.name + "].maybeNotifyFinally()");
+
+      Assert.ok(this._waiter !== null, "must be waiting now");
+
+      if (self._data.length) {
+        dumpn(
+          "*** data still pending, normal notifications will signal " +
+            "completion"
+        );
+        return;
+      }
+
+      // No data waiting to be written, so notify.  We could just close the
+      // stream, but that's less faithful to the server's behavior (it doesn't
+      // close the stream, and we're pretending to impersonate the server as
+      // much as we can here), so instead we're going to notify when no data
+      // can be read.  The CopyTest has already been flagged as complete, so
+      // the stream listener will detect that this is a wrap-it-up notify and
+      // invoke the next test.
+      this._notify();
+    },
+
+    /**
+     * Dispatches an event to call a previously-registered stream-ready
+     * callback.
+     */
+    _notify: function _notify() {
+      dumpn("*** [" + this.name + "]._notify()");
+
+      var waiter = this._waiter;
+      Assert.ok(waiter !== null, "no waiter?");
+
+      if (this._event === null) {
+        var event = (this._event = {
+          run: function run() {
+            input._waiter = null;
+            input._event = null;
+            try {
+              Assert.ok(
+                !Components.isSuccessCode(self._status) ||
+                  input._readable >= waiter.requestedCount
+              );
+              waiter.callback.onInputStreamReady(input);
+            } catch (e) {
+              do_throw("error calling onInputStreamReady: " + e);
+            }
+          },
+        });
+        waiter.eventTarget.dispatch(event, Ci.nsIThread.DISPATCH_NORMAL);
+      }
+    },
+  });
+
+  /** The output end of this pipe. */
+  var output = (this.outputStream = {
+    /** A name for this stream, used in debugging output. */
+    name: name + " output",
+
+    /**
+     * The number of bytes of data which may be written to this pipe without
+     * blocking.
+     */
+    _writable: 0,
+
+    /**
+     * The increments in which pending data should be written, rather than
+     * simply defaulting to the amount requested (which, given that
+     * input.asyncWait precisely respects the requestedCount argument, will
+     * ordinarily always be writable in that amount), as an array whose
+     * elements from start to finish are the number of bytes to write each
+     * time write() or writeByteArray() is subsequently called.  The sum of
+     * the values in this array, if this array is not empty, is always equal
+     * to this._writable.
+     */
+    _writableAmounts: [],
+
+    /**
+     * Data regarding a pending stream-ready callback on this, or null if no
+     * callback is currently waiting to be called.
+     */
+    _waiter: null,
+
+    /**
+     * The event currently dispatched to make a stream-ready callback, if any
+     * such callback is currently ready to be made and not already in
+     * progress, or null when no callback is waiting to happen.
+     */
+    _event: null,
+
+    /**
+     * A stream-ready constructor to wrap an existing callback to intercept
+     * stream-ready notifications, or null if notifications shouldn't be
+     * wrapped at all.
+     */
+    _streamReadyInterceptCreator: null,
+
+    /**
+     * Registers a stream-ready wrapper creator function so that a
+     * stream-ready callback made in the future can be wrapped.
+     */
+    interceptStreamReadyCallbacks(streamReadyInterceptCreator) {
+      dumpn("*** [" + this.name + "].interceptStreamReadyCallbacks");
+
+      Assert.ok(
+        this._streamReadyInterceptCreator !== null,
+        "intercepting onOutputStreamReady twice"
+      );
+      this._streamReadyInterceptCreator = streamReadyInterceptCreator;
+      if (this._waiter) {
+        this._waiter.callback = new streamReadyInterceptCreator(
+          this._waiter.callback
+        );
+      }
+    },
+
+    /**
+     * Removes a previously-registered stream-ready wrapper creator function,
+     * also clearing any current wrapping.
+     */
+    removeStreamReadyInterceptor() {
+      dumpn("*** [" + this.name + "].removeStreamReadyInterceptor()");
+
+      Assert.ok(
+        this._streamReadyInterceptCreator !== null,
+        "removing interceptor when none present?"
+      );
+      this._streamReadyInterceptCreator = null;
+      if (this._waiter) {
+        this._waiter.callback = this._waiter.callback.wrappedCallback;
+      }
+    },
+
+    //
+    // see nsIAsyncOutputStream.asyncWait
+    //
+    asyncWait: function asyncWait(callback, flags, requestedCount, target) {
+      dumpn("*** [" + this.name + "].asyncWait");
+
+      Assert.ok(callback && typeof callback !== "function");
+
+      var closureOnly =
+        (flags & Ci.nsIAsyncInputStream.WAIT_CLOSURE_ONLY) !== 0;
+
+      Assert.ok(
+        this._waiter === null || (this._waiter.closureOnly && !closureOnly),
+        "asyncWait already called with a non-closure-only " +
+          "callback?  unexpected!"
+      );
+
+      this._waiter = {
+        callback: this._streamReadyInterceptCreator
+          ? new this._streamReadyInterceptCreator(callback)
+          : callback,
+        closureOnly,
+        requestedCount,
+        eventTarget: target,
+        toString: function toString() {
+          return (
+            "waiter(" +
+            (closureOnly ? "closure only, " : "") +
+            "requestedCount: " +
+            requestedCount +
+            ", target: " +
+            target +
+            ")"
+          );
+        },
+      };
+
+      if (
+        (!closureOnly && this._writable >= requestedCount) ||
+        !Components.isSuccessCode(this.status)
+      ) {
+        this._notify();
+      }
+    },
+
+    //
+    // see nsIAsyncOutputStream.closeWithStatus
+    //
+    closeWithStatus: function closeWithStatus(status) {
+      dumpn("*** [" + this.name + "].closeWithStatus(" + status + ")");
+
+      if (!Components.isSuccessCode(self._status)) {
+        dumpn(
+          "*** ignoring redundant closure of [input " +
+            this.name +
+            "] " +
+            "because it's already closed (status " +
+            self._status +
+            ")"
+        );
+        return;
+      }
+
+      if (Components.isSuccessCode(status)) {
+        status = Cr.NS_BASE_STREAM_CLOSED;
+      }
+
+      self._status = status;
+
+      if (input._waiter) {
+        input._notify();
+      }
+      if (this._waiter) {
+        this._notify();
+      }
+    },
+
+    //
+    // see nsIBinaryOutputStream.writeByteArray
+    //
+    writeByteArray: function writeByteArray(bytes) {
+      dumpn(`*** [${this.name}].writeByteArray([${bytes}])`);
+
+      if (!Components.isSuccessCode(self._status)) {
+        throw self._status;
+      }
+
+      Assert.equal(
+        this._writableAmounts.length,
+        0,
+        "writeByteArray can't support specified-length writes"
+      );
+
+      if (this._writable < bytes.length) {
+        throw Components.Exception("", Cr.NS_BASE_STREAM_WOULD_BLOCK);
+      }
+
+      self._data.push.apply(self._data, bytes);
+      this._writable -= bytes.length;
+
+      if (
+        input._readable === Infinity &&
+        input._waiter &&
+        !input._waiter.closureOnly
+      ) {
+        input._notify();
+      }
+    },
+
+    //
+    // see nsIOutputStream.write
+    //
+    write: function write(str, length) {
+      dumpn("*** [" + this.name + "].write");
+
+      Assert.equal(str.length, length, "sanity");
+      if (!Components.isSuccessCode(self._status)) {
+        throw self._status;
+      }
+      if (this._writable === 0) {
+        throw Components.Exception("", Cr.NS_BASE_STREAM_WOULD_BLOCK);
+      }
+
+      var actualWritten;
+      if (this._writableAmounts.length === 0) {
+        actualWritten = Math.min(this._writable, length);
+      } else {
+        Assert.ok(
+          this._writable >= this._writableAmounts[0],
+          "writable amounts value greater than writable data?"
+        );
+        Assert.equal(
+          this._writable,
+          sum(this._writableAmounts),
+          "total writable amount not equal to sum of writable increments"
+        );
+        actualWritten = this._writableAmounts.shift();
+      }
+
+      var bytes = str
+        .substring(0, actualWritten)
+        .split("")
+        .map(function (v) {
+          return v.charCodeAt(0);
+        });
+
+      self._data.push.apply(self._data, bytes);
+      this._writable -= actualWritten;
+
+      if (
+        input._readable === Infinity &&
+        input._waiter &&
+        !input._waiter.closureOnly
+      ) {
+        input._notify();
+      }
+
+      return actualWritten;
+    },
+
+    /**
+     * Increase the amount of data that can be written without blocking by the
+     * given number of bytes, triggering future notifications when required.
+     *
+     * @param count : uint
+     *   the number of bytes of additional data to make writable
+     */
+    makeWritable: function makeWritable(count) {
+      dumpn("*** [" + this.name + "].makeWritable(" + count + ")");
+
+      Assert.ok(Components.isSuccessCode(self._status));
+
+      this._writable += count;
+
+      var waiter = this._waiter;
+      if (
+        waiter &&
+        !waiter.closureOnly &&
+        waiter.requestedCount <= this._writable
+      ) {
+        this._notify();
+      }
+    },
+
+    /**
+     * Increase the amount of data that can be written without blocking, but
+     * do so by specifying a number of bytes that will be written each time
+     * a write occurs, even as asyncWait notifications are initially triggered
+     * as usual.  Thus, rather than writes eagerly writing everything possible
+     * at each step, attempts to write out data by segment devolve into a
+     * partial segment write, then another, and so on until the amount of data
+     * specified as permitted to be written, has been written.
+     *
+     * Note that the writeByteArray method is incompatible with the previous
+     * calling of this method, in that, until all increments provided to this
+     * method have been consumed, writeByteArray cannot be called.  Once all
+     * increments have been consumed, writeByteArray may again be called.
+     *
+     * @param increments : [uint]
+     *   an array whose elements are positive numbers of bytes to permit to be
+     *   written each time write() is subsequently called on this, ignoring
+     *   the total amount of writable space specified by the sum of all
+     *   increments
+     */
+    makeWritableByIncrements: function makeWritableByIncrements(increments) {
+      dumpn(
+        "*** [" +
+          this.name +
+          "].makeWritableByIncrements" +
+          "([" +
+          increments.join(", ") +
+          "])"
+      );
+
+      Assert.greater(increments.length, 0, "bad increments");
+      Assert.ok(
+        increments.every(function (v) {
+          return v > 0;
+        }),
+        "zero increment?"
+      );
+
+      Assert.ok(Components.isSuccessCode(self._status));
+
+      this._writable += sum(increments);
+      this._writableAmounts = increments;
+
+      var waiter = this._waiter;
+      if (
+        waiter &&
+        !waiter.closureOnly &&
+        waiter.requestedCount <= this._writable
+      ) {
+        this._notify();
+      }
+    },
+
+    /**
+     * Dispatches an event to call a previously-registered stream-ready
+     * callback.
+     */
+    _notify: function _notify() {
+      dumpn("*** [" + this.name + "]._notify()");
+
+      var waiter = this._waiter;
+      Assert.ok(waiter !== null, "no waiter?");
+
+      if (this._event === null) {
+        var event = (this._event = {
+          run: function run() {
+            output._waiter = null;
+            output._event = null;
+
+            try {
+              waiter.callback.onOutputStreamReady(output);
+            } catch (e) {
+              do_throw("error calling onOutputStreamReady: " + e);
+            }
+          },
+        });
+        waiter.eventTarget.dispatch(event, Ci.nsIThread.DISPATCH_NORMAL);
+      }
+    },
+  });
+}
+
+/**
+ * Represents a sequence of interactions to perform with a copier, in a given
+ * order and at the desired time intervals.
+ *
+ * @param name : string
+ *   test name, used in debugging output
+ */
+function CopyTest(name, next) {
+  /** Name used in debugging output. */
+  this.name = name;
+
+  /** A function called when the test completes. */
+  this._done = next;
+
+  var sourcePipe = new CustomPipe(name + "-source");
+
+  /** The source of data for the copier to copy. */
+  this._source = sourcePipe.inputStream;
+
+  /**
+   * The sink to which to write data which will appear in the copier's source.
+   */
+  this._copyableDataStream = sourcePipe.outputStream;
+
+  var sinkPipe = new CustomPipe(name + "-sink");
+
+  /** The sink to which the copier copies data. */
+  this._sink = sinkPipe.outputStream;
+
+  /** Input stream from which to read data the copier's written to its sink. */
+  this._copiedDataStream = sinkPipe.inputStream;
+
+  this._copiedDataStream.disableReadabilityLimit();
+
+  /**
+   * True if there's a callback waiting to read data written by the copier to
+   * its output, from the input end of the pipe representing the copier's sink.
+   */
+  this._waitingForData = false;
+
+  /**
+   * An array of the bytes of data expected to be written to output by the
+   * copier when this test runs.
+   */
+  this._expectedData = undefined;
+
+  /** Array of bytes of data received so far. */
+  this._receivedData = [];
+
+  /** The expected final status returned by the copier. */
+  this._expectedStatus = -1;
+
+  /** The actual final status returned by the copier. */
+  this._actualStatus = -1;
+
+  /** The most recent sequence of bytes written to output by the copier. */
+  this._lastQuantum = [];
+
+  /**
+   * True iff we've received the last quantum of data written to the sink by the
+   * copier.
+   */
+  this._allDataWritten = false;
+
+  /**
+   * True iff the copier has notified its associated stream listener of
+   * completion.
+   */
+  this._copyingFinished = false;
+
+  /** Index of the next task to execute while driving the copier. */
+  this._currentTask = 0;
+
+  /** Array containing all tasks to run. */
+  this._tasks = [];
+
+  /** The copier used by this test. */
+  this._copier = new WriteThroughCopier(this._source, this._sink, this, null);
+
+  // Start watching for data written by the copier to the sink.
+  this._waitForWrittenData();
+}
+CopyTest.prototype = {
+  /**
+   * Adds the given array of bytes to data in the copier's source.
+   *
+   * @param bytes : [uint]
+   *   array of bytes of data to add to the source for the copier
+   */
+  addToSource: function addToSource(bytes) {
+    var self = this;
+    this._addToTasks(function addToSourceTask() {
+      note("addToSourceTask");
+
+      try {
+        self._copyableDataStream.makeWritable(bytes.length);
+        self._copyableDataStream.writeByteArray(bytes);
+      } finally {
+        self._stageNextTask();
+      }
+    });
+  },
+
+  /**
+   * Makes bytes of data previously added to the source available to be read by
+   * the copier.
+   *
+   * @param count : uint
+   *   number of bytes to make available for reading
+   */
+  makeSourceReadable: function makeSourceReadable(count) {
+    var self = this;
+    this._addToTasks(function makeSourceReadableTask() {
+      note("makeSourceReadableTask");
+
+      self._source.makeReadable(count);
+      self._stageNextTask();
+    });
+  },
+
+  /**
+   * Increases available space in the sink by the given amount, waits for the
+   * given series of arrays of bytes to be written to sink by the copier, and
+   * causes execution to asynchronously continue to the next task when the last
+   * of those arrays of bytes is received.
+   *
+   * @param bytes : uint
+   *   number of bytes of space to make available in the sink
+   * @param dataQuantums : [[uint]]
+   *   array of byte arrays to expect to be written in sequence to the sink
+   */
+  makeSinkWritableAndWaitFor: function makeSinkWritableAndWaitFor(
+    bytes,
+    dataQuantums
+  ) {
+    var self = this;
+
+    Assert.equal(
+      bytes,
+      dataQuantums.reduce(function (partial, current) {
+        return partial + current.length;
+      }, 0),
+      "bytes/quantums mismatch"
+    );
+
+    function increaseSinkSpaceTask() {
+      /* Now do the actual work to trigger the interceptor. */
+      self._sink.makeWritable(bytes);
+    }
+
+    this._waitForHelper(
+      "increaseSinkSpaceTask",
+      dataQuantums,
+      increaseSinkSpaceTask
+    );
+  },
+
+  /**
+   * Increases available space in the sink by the given amount, waits for the
+   * given series of arrays of bytes to be written to sink by the copier, and
+   * causes execution to asynchronously continue to the next task when the last
+   * of those arrays of bytes is received.
+   *
+   * @param bytes : uint
+   *   number of bytes of space to make available in the sink
+   * @param dataQuantums : [[uint]]
+   *   array of byte arrays to expect to be written in sequence to the sink
+   */
+  makeSinkWritableByIncrementsAndWaitFor:
+    function makeSinkWritableByIncrementsAndWaitFor(bytes, dataQuantums) {
+      var self = this;
+
+      var desiredAmounts = dataQuantums.map(function (v) {
+        return v.length;
+      });
+      Assert.equal(bytes, sum(desiredAmounts), "bytes/quantums mismatch");
+
+      function increaseSinkSpaceByIncrementsTask() {
+        /* Now do the actual work to trigger the interceptor incrementally. */
+        self._sink.makeWritableByIncrements(desiredAmounts);
+      }
+
+      this._waitForHelper(
+        "increaseSinkSpaceByIncrementsTask",
+        dataQuantums,
+        increaseSinkSpaceByIncrementsTask
+      );
+    },
+
+  /**
+   * Close the copier's source stream, then asynchronously continue to the next
+   * task.
+   *
+   * @param status : nsresult
+   *   the status to provide when closing the copier's source stream
+   */
+  closeSource: function closeSource(status) {
+    var self = this;
+
+    this._addToTasks(function closeSourceTask() {
+      note("closeSourceTask");
+
+      self._source.closeWithStatus(status);
+      self._stageNextTask();
+    });
+  },
+
+  /**
+   * Close the copier's source stream, then wait for the given number of bytes
+   * and for the given series of arrays of bytes to be written to the sink, then
+   * asynchronously continue to the next task.
+   *
+   * @param status : nsresult
+   *   the status to provide when closing the copier's source stream
+   * @param bytes : uint
+   *   number of bytes of space to make available in the sink
+   * @param dataQuantums : [[uint]]
+   *   array of byte arrays to expect to be written in sequence to the sink
+   */
+  closeSourceAndWaitFor: function closeSourceAndWaitFor(
+    status,
+    bytes,
+    dataQuantums
+  ) {
+    var self = this;
+
+    Assert.equal(
+      bytes,
+      sum(
+        dataQuantums.map(function (v) {
+          return v.length;
+        })
+      ),
+      "bytes/quantums mismatch"
+    );
+
+    function closeSourceAndWaitForTask() {
+      self._sink.makeWritable(bytes);
+      self._copyableDataStream.closeWithStatus(status);
+    }
+
+    this._waitForHelper(
+      "closeSourceAndWaitForTask",
+      dataQuantums,
+      closeSourceAndWaitForTask
+    );
+  },
+
+  /**
+   * Closes the copier's sink stream, providing the given status, then
+   * asynchronously continue to the next task.
+   *
+   * @param status : nsresult
+   *   the status to provide when closing the copier's sink stream
+   */
+  closeSink: function closeSink(status) {
+    var self = this;
+    this._addToTasks(function closeSinkTask() {
+      note("closeSinkTask");
+
+      self._sink.closeWithStatus(status);
+      self._stageNextTask();
+    });
+  },
+
+  /**
+   * Closes the copier's source stream, then immediately closes the copier's
+   * sink stream, then asynchronously continues to the next task.
+   *
+   * @param sourceStatus : nsresult
+   *   the status to provide when closing the copier's source stream
+   * @param sinkStatus : nsresult
+   *   the status to provide when closing the copier's sink stream
+   */
+  closeSourceThenSink: function closeSourceThenSink(sourceStatus, sinkStatus) {
+    var self = this;
+    this._addToTasks(function closeSourceThenSinkTask() {
+      note("closeSourceThenSinkTask");
+
+      self._source.closeWithStatus(sourceStatus);
+      self._sink.closeWithStatus(sinkStatus);
+      self._stageNextTask();
+    });
+  },
+
+  /**
+   * Closes the copier's sink stream, then immediately closes the copier's
+   * source stream, then asynchronously continues to the next task.
+   *
+   * @param sinkStatus : nsresult
+   *   the status to provide when closing the copier's sink stream
+   * @param sourceStatus : nsresult
+   *   the status to provide when closing the copier's source stream
+   */
+  closeSinkThenSource: function closeSinkThenSource(sinkStatus, sourceStatus) {
+    var self = this;
+    this._addToTasks(function closeSinkThenSourceTask() {
+      note("closeSinkThenSource");
+
+      self._sink.closeWithStatus(sinkStatus);
+      self._source.closeWithStatus(sourceStatus);
+      self._stageNextTask();
+    });
+  },
+
+  /**
+   * Indicates that the given status is expected to be returned when the stream
+   * listener for the copy indicates completion, that the expected data copied
+   * by the copier to sink are the concatenation of the arrays of bytes in
+   * receivedData, and kicks off the tasks in this test.
+   *
+   * @param expectedStatus : nsresult
+   *   the status expected to be returned by the copier at completion
+   * @param receivedData : [[uint]]
+   *   an array containing arrays of bytes whose concatenation constitutes the
+   *   expected copied data
+   */
+  expect: function expect(expectedStatus, receivedData) {
+    this._expectedStatus = expectedStatus;
+    this._expectedData = [];
+    for (var i = 0, sz = receivedData.length; i < sz; i++) {
+      this._expectedData.push.apply(this._expectedData, receivedData[i]);
+    }
+
+    this._stageNextTask();
+  },
+
+  /**
+   * Sets up a stream interceptor that will verify that each piece of data
+   * written to the sink by the copier corresponds to the currently expected
+   * pieces of data, calls the trigger, then waits for those pieces of data to
+   * be received.  Once all have been received, the interceptor is removed and
+   * the next task is asynchronously executed.
+   *
+   * @param name : string
+   *   name of the task created by this, used in debugging output
+   * @param dataQuantums : [[uint]]
+   *   array of expected arrays of bytes to be written to the sink by the copier
+   * @param trigger : function() : void
+   *   function to call after setting up the interceptor to wait for
+   *   notifications (which will be generated as a result of this function's
+   *   actions)
+   */
+  _waitForHelper: function _waitForHelper(name, dataQuantums, trigger) {
+    var self = this;
+    this._addToTasks(function waitForHelperTask() {
+      note(name);
+
+      var quantumIndex = 0;
+
+      /*
+       * Intercept all data-available notifications so we can continue when all
+       * the ones we expect have been received.
+       */
+      var streamReadyCallback = {
+        onInputStreamReady: function wrapperOnInputStreamReady(input) {
+          dumpn(
+            "*** streamReadyCallback.onInputStreamReady" +
+              "(" +
+              input.name +
+              ")"
+          );
+
+          Assert.equal(this, streamReadyCallback, "sanity");
+
+          try {
+            if (quantumIndex < dataQuantums.length) {
+              var quantum = dataQuantums[quantumIndex++];
+              var sz = quantum.length;
+              Assert.equal(
+                self._lastQuantum.length,
+                sz,
+                "different quantum lengths"
+              );
+              for (var i = 0; i < sz; i++) {
+                Assert.equal(
+                  self._lastQuantum[i],
+                  quantum[i],
+                  "bad data at " + i
+                );
+              }
+
+              dumpn(
+                "*** waiting to check remaining " +
+                  (dataQuantums.length - quantumIndex) +
+                  " quantums..."
+              );
+            }
+          } finally {
+            if (quantumIndex === dataQuantums.length) {
+              dumpn("*** data checks completed!  next task...");
+              self._copiedDataStream.removeStreamReadyInterceptor();
+              self._stageNextTask();
+            }
+          }
+        },
+      };
+
+      var interceptor = createStreamReadyInterceptor(
+        streamReadyCallback,
+        "onInputStreamReady"
+      );
+      self._copiedDataStream.interceptStreamReadyCallbacks(interceptor);
+
+      /* Do the deed. */
+      trigger();
+    });
+  },
+
+  /**
+   * Initiates asynchronous waiting for data written to the copier's sink to be
+   * available for reading from the input end of the sink's pipe.  The callback
+   * stores the received data for comparison in the interceptor used in the
+   * callback added by _waitForHelper and signals test completion when it
+   * receives a zero-data-available notification (if the copier has notified
+   * that it is finished; otherwise allows execution to continue until that has
+   * occurred).
+   */
+  _waitForWrittenData: function _waitForWrittenData() {
+    dumpn("*** _waitForWrittenData (" + this.name + ")");
+
+    var self = this;
+    var outputWrittenWatcher = {
+      onInputStreamReady: function onInputStreamReady(input) {
+        dumpn(
+          // eslint-disable-next-line no-useless-concat
+          "*** outputWrittenWatcher.onInputStreamReady" + "(" + input.name + ")"
+        );
+
+        if (self._allDataWritten) {
+          do_throw(
+            "ruh-roh!  why are we getting notified of more data " +
+              "after we should have received all of it?"
+          );
+        }
+
+        self._waitingForData = false;
+
+        try {
+          var avail = input.available();
+        } catch (e) {
+          dumpn("*** available() threw!  error: " + e);
+          if (self._completed) {
+            dumpn(
+              "*** NB: this isn't a problem, because we've copied " +
+                "completely now, and this notify may have been expedited " +
+                "by maybeNotifyFinally such that we're being called when " +
+                "we can *guarantee* nothing is available any more"
+            );
+          }
+          avail = 0;
+        }
+
+        if (avail > 0) {
+          var data = input.readByteArray(avail);
+          Assert.equal(
+            data.length,
+            avail,
+            "readByteArray returned wrong number of bytes?"
+          );
+          self._lastQuantum = data;
+          self._receivedData.push.apply(self._receivedData, data);
+        }
+
+        if (avail === 0) {
+          dumpn("*** all data received!");
+
+          self._allDataWritten = true;
+
+          if (self._copyingFinished) {
+            dumpn("*** copying already finished, continuing to next test");
+            self._testComplete();
+          } else {
+            dumpn("*** copying not finished, waiting for that to happen");
+          }
+
+          return;
+        }
+
+        self._waitForWrittenData();
+      },
+    };
+
+    this._copiedDataStream.asyncWait(
+      outputWrittenWatcher,
+      0,
+      1,
+      Services.tm.currentThread
+    );
+    this._waitingForData = true;
+  },
+
+  /**
+   * Indicates this test is complete, does the final data-received and copy
+   * status comparisons, and calls the test-completion function provided when
+   * this test was first created.
+   */
+  _testComplete: function _testComplete() {
+    dumpn("*** CopyTest(" + this.name + ") complete!  On to the next test...");
+
+    try {
+      Assert.ok(this._allDataWritten, "expect all data written now!");
+      Assert.ok(this._copyingFinished, "expect copying finished now!");
+
+      Assert.equal(
+        this._actualStatus,
+        this._expectedStatus,
+        "wrong final status"
+      );
+
+      var expected = this._expectedData,
+        received = this._receivedData;
+      dumpn("received: [" + received + "], expected: [" + expected + "]");
+      Assert.equal(received.length, expected.length, "wrong data");
+      for (var i = 0, sz = expected.length; i < sz; i++) {
+        Assert.equal(received[i], expected[i], "bad data at " + i);
+      }
+    } catch (e) {
+      dumpn("!!! ERROR PERFORMING FINAL " + this.name + " CHECKS!  " + e);
+      throw e;
+    } finally {
+      dumpn(
+        "*** CopyTest(" +
+          this.name +
+          ") complete!  " +
+          "Invoking test-completion callback..."
+      );
+      this._done();
+    }
+  },
+
+  /** Dispatches an event at this thread which will run the next task. */
+  _stageNextTask: function _stageNextTask() {
+    dumpn("*** CopyTest(" + this.name + ")._stageNextTask()");
+
+    if (this._currentTask === this._tasks.length) {
+      dumpn("*** CopyTest(" + this.name + ") tasks complete!");
+      return;
+    }
+
+    var task = this._tasks[this._currentTask++];
+    var event = {
+      run: function run() {
+        try {
+          task();
+        } catch (e) {
+          do_throw("exception thrown running task: " + e);
+        }
+      },
+    };
+    Services.tm.dispatchToMainThread(event);
+  },
+
+  /**
+   * Adds the given function as a task to be run at a later time.
+   *
+   * @param task : function() : void
+   *   the function to call as a task
+   */
+  _addToTasks: function _addToTasks(task) {
+    this._tasks.push(task);
+  },
+
+  //
+  // see nsIRequestObserver.onStartRequest
+  //
+  onStartRequest: function onStartRequest(self) {
+    dumpn("*** CopyTest.onStartRequest (" + self.name + ")");
+
+    Assert.equal(this._receivedData.length, 0);
+    Assert.equal(this._lastQuantum.length, 0);
+  },
+
+  //
+  // see nsIRequestObserver.onStopRequest
+  //
+  onStopRequest: function onStopRequest(self, status) {
+    dumpn("*** CopyTest.onStopRequest (" + self.name + ", " + status + ")");
+
+    this._actualStatus = status;
+
+    this._copyingFinished = true;
+
+    if (this._allDataWritten) {
+      dumpn("*** all data written, continuing with remaining tests...");
+      this._testComplete();
+    } else {
+      /*
+       * Everything's copied as far as the copier is concerned.  However, there
+       * may be a backup transferring from the output end of the copy sink to
+       * the input end where we can actually verify that the expected data was
+       * written as expected, because that transfer occurs asynchronously.  If
+       * we do final data-received checks now, we'll miss still-pending data.
+       * Therefore, to wrap up this copy test we still need to asynchronously
+       * wait on the input end of the sink until we hit end-of-stream or some
+       * error condition.  Then we know we're done and can continue with the
+       * next test.
+       */
+      dumpn("*** not all data copied, waiting for that to happen...");
+
+      if (!this._waitingForData) {
+        this._waitForWrittenData();
+      }
+
+      this._copiedDataStream.maybeNotifyFinally();
+    }
+  },
+};
diff --git a/netwerk/test/httpserver/test/test_basic_functionality.js b/netwerk/test/httpserver/test/test_basic_functionality.js
new file mode 100644
index 0000000000..b8864abd17
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_basic_functionality.js
@@ -0,0 +1,182 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Basic functionality test, from the client programmer's POV.
+ */
+
+ChromeUtils.defineLazyGetter(this, "port", function () {
+  return srv.identity.primaryPort;
+});
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + port + "/objHandler",
+      null,
+      start_objHandler,
+      null
+    ),
+    new Test(
+      "http://localhost:" + port + "/functionHandler",
+      null,
+      start_functionHandler,
+      null
+    ),
+    new Test(
+      "http://localhost:" + port + "/nonexistent-path",
+      null,
+      start_non_existent_path,
+      null
+    ),
+    new Test(
+      "http://localhost:" + port + "/lotsOfHeaders",
+      null,
+      start_lots_of_headers,
+      null
+    ),
+  ];
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+
+  // base path
+  // XXX should actually test this works with a file by comparing streams!
+  var path = Services.dirsvc.get("CurWorkD", Ci.nsIFile);
+  srv.registerDirectory("/", path);
+
+  // register a few test paths
+  srv.registerPathHandler("/objHandler", objHandler);
+  srv.registerPathHandler("/functionHandler", functionHandler);
+  srv.registerPathHandler("/lotsOfHeaders", lotsOfHeadersHandler);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+const HEADER_COUNT = 1000;
+
+// TEST DATA
+
+// common properties *always* appended by server
+// or invariants for every URL in paths
+function commonCheck(ch) {
+  Assert.ok(ch.contentLength > -1);
+  Assert.equal(ch.getResponseHeader("connection"), "close");
+  Assert.ok(!ch.isNoStoreResponse());
+  Assert.ok(!ch.isPrivateResponse());
+}
+
+function start_objHandler(ch) {
+  commonCheck(ch);
+
+  Assert.equal(ch.responseStatus, 200);
+  Assert.ok(ch.requestSucceeded);
+  Assert.equal(ch.getResponseHeader("content-type"), "text/plain");
+  Assert.equal(ch.responseStatusText, "OK");
+
+  var reqMin = {},
+    reqMaj = {},
+    respMin = {},
+    respMaj = {};
+  ch.getRequestVersion(reqMaj, reqMin);
+  ch.getResponseVersion(respMaj, respMin);
+  Assert.ok(reqMaj.value == respMaj.value && reqMin.value == respMin.value);
+}
+
+function start_functionHandler(ch) {
+  commonCheck(ch);
+
+  Assert.equal(ch.responseStatus, 404);
+  Assert.ok(!ch.requestSucceeded);
+  Assert.equal(ch.getResponseHeader("foopy"), "quux-baz");
+  Assert.equal(ch.responseStatusText, "Page Not Found");
+
+  var reqMin = {},
+    reqMaj = {},
+    respMin = {},
+    respMaj = {};
+  ch.getRequestVersion(reqMaj, reqMin);
+  ch.getResponseVersion(respMaj, respMin);
+  Assert.ok(reqMaj.value == 1 && reqMin.value == 1);
+  Assert.ok(respMaj.value == 1 && respMin.value == 1);
+}
+
+function start_non_existent_path(ch) {
+  commonCheck(ch);
+
+  Assert.equal(ch.responseStatus, 404);
+  Assert.ok(!ch.requestSucceeded);
+}
+
+function start_lots_of_headers(ch) {
+  commonCheck(ch);
+
+  Assert.equal(ch.responseStatus, 200);
+  Assert.ok(ch.requestSucceeded);
+
+  for (var i = 0; i < HEADER_COUNT; i++) {
+    Assert.equal(ch.getResponseHeader("X-Header-" + i), "value " + i);
+  }
+}
+
+// PATH HANDLERS
+
+// /objHandler
+var objHandler = {
+  handle(metadata, response) {
+    response.setStatusLine(metadata.httpVersion, 200, "OK");
+    response.setHeader("Content-Type", "text/plain", false);
+
+    var body = "Request (slightly reformatted):\n\n";
+    body += metadata.method + " " + metadata.path;
+
+    Assert.equal(metadata.port, port);
+
+    if (metadata.queryString) {
+      body += "?" + metadata.queryString;
+    }
+
+    body += " HTTP/" + metadata.httpVersion + "\n";
+
+    var headEnum = metadata.headers;
+    while (headEnum.hasMoreElements()) {
+      var fieldName = headEnum
+        .getNext()
+        .QueryInterface(Ci.nsISupportsString).data;
+      body += fieldName + ": " + metadata.getHeader(fieldName) + "\n";
+    }
+
+    response.bodyOutputStream.write(body, body.length);
+  },
+  QueryInterface: ChromeUtils.generateQI(["nsIHttpRequestHandler"]),
+};
+
+// /functionHandler
+function functionHandler(metadata, response) {
+  response.setStatusLine("1.1", 404, "Page Not Found");
+  response.setHeader("foopy", "quux-baz", false);
+
+  Assert.equal(metadata.port, port);
+  Assert.equal(metadata.host, "localhost");
+  Assert.equal(metadata.path.charAt(0), "/");
+
+  var body = "this is text\n";
+  response.bodyOutputStream.write(body, body.length);
+}
+
+// /lotsOfHeaders
+function lotsOfHeadersHandler(request, response) {
+  response.setHeader("Content-Type", "text/plain", false);
+
+  for (var i = 0; i < HEADER_COUNT; i++) {
+    response.setHeader("X-Header-" + i, "value " + i, false);
+  }
+}
diff --git a/netwerk/test/httpserver/test/test_body_length.js b/netwerk/test/httpserver/test/test_body_length.js
new file mode 100644
index 0000000000..85f35d7441
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_body_length.js
@@ -0,0 +1,68 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests that the Content-Length header in incoming requests is interpreted as
+ * a decimal number, even if it has the form (including leading zero) of an
+ * octal number.
+ */
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+  srv.registerPathHandler("/content-length", contentLength);
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+const REQUEST_DATA = "12345678901234567";
+
+function contentLength(request, response) {
+  Assert.equal(request.method, "POST");
+  Assert.equal(request.getHeader("Content-Length"), "017");
+
+  var body = new ScriptableInputStream(request.bodyInputStream);
+
+  var avail;
+  var data = "";
+  while ((avail = body.available()) > 0) {
+    data += body.read(avail);
+  }
+
+  Assert.equal(data, REQUEST_DATA);
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/content-length",
+      init_content_length
+    ),
+  ];
+});
+
+function init_content_length(ch) {
+  var content = Cc["@mozilla.org/io/string-input-stream;1"].createInstance(
+    Ci.nsIStringInputStream
+  );
+  content.data = REQUEST_DATA;
+
+  ch.QueryInterface(Ci.nsIUploadChannel).setUploadStream(
+    content,
+    "text/plain",
+    REQUEST_DATA.length
+  );
+
+  // Override the values implicitly set by setUploadStream above.
+  ch.requestMethod = "POST";
+  ch.setRequestHeader("Content-Length", "017", false); // 17 bytes, not 15
+}
diff --git a/netwerk/test/httpserver/test/test_byte_range.js b/netwerk/test/httpserver/test/test_byte_range.js
new file mode 100644
index 0000000000..ef92824734
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_byte_range.js
@@ -0,0 +1,272 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// checks if a byte range request and non-byte range request retrieve the
+// correct data.
+
+var srv;
+ChromeUtils.defineLazyGetter(this, "PREFIX", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange,
+      start_byterange,
+      stop_byterange
+    ),
+    new Test(PREFIX + "/range.txt", init_byterange2, start_byterange2),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange3,
+      start_byterange3,
+      stop_byterange3
+    ),
+    new Test(PREFIX + "/range.txt", init_byterange4, start_byterange4),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange5,
+      start_byterange5,
+      stop_byterange5
+    ),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange6,
+      start_byterange6,
+      stop_byterange6
+    ),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange7,
+      start_byterange7,
+      stop_byterange7
+    ),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange8,
+      start_byterange8,
+      stop_byterange8
+    ),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange9,
+      start_byterange9,
+      stop_byterange9
+    ),
+    new Test(PREFIX + "/range.txt", init_byterange10, start_byterange10),
+    new Test(
+      PREFIX + "/range.txt",
+      init_byterange11,
+      start_byterange11,
+      stop_byterange11
+    ),
+    new Test(PREFIX + "/empty.txt", null, start_byterange12, stop_byterange12),
+    new Test(
+      PREFIX + "/headers.txt",
+      init_byterange13,
+      start_byterange13,
+      null
+    ),
+    new Test(PREFIX + "/range.txt", null, start_normal, stop_normal),
+  ];
+});
+
+function run_test() {
+  srv = createServer();
+  var dir = do_get_file("data/ranges/");
+  srv.registerDirectory("/", dir);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+function start_normal(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.getResponseHeader("Content-Length"), "21");
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+}
+
+function stop_normal(ch, status, data) {
+  Assert.equal(data.length, 21);
+  Assert.equal(data[0], 0x54);
+  Assert.equal(data[20], 0x0a);
+}
+
+function init_byterange(ch) {
+  ch.setRequestHeader("Range", "bytes=10-", false);
+}
+
+function start_byterange(ch) {
+  Assert.equal(ch.responseStatus, 206);
+  Assert.equal(ch.getResponseHeader("Content-Length"), "11");
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+  Assert.equal(ch.getResponseHeader("Content-Range"), "bytes 10-20/21");
+}
+
+function stop_byterange(ch, status, data) {
+  Assert.equal(data.length, 11);
+  Assert.equal(data[0], 0x64);
+  Assert.equal(data[10], 0x0a);
+}
+
+function init_byterange2(ch) {
+  ch.setRequestHeader("Range", "bytes=21-", false);
+}
+
+function start_byterange2(ch) {
+  Assert.equal(ch.responseStatus, 416);
+}
+
+function init_byterange3(ch) {
+  ch.setRequestHeader("Range", "bytes=10-15", false);
+}
+
+function start_byterange3(ch) {
+  Assert.equal(ch.responseStatus, 206);
+  Assert.equal(ch.getResponseHeader("Content-Length"), "6");
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+  Assert.equal(ch.getResponseHeader("Content-Range"), "bytes 10-15/21");
+}
+
+function stop_byterange3(ch, status, data) {
+  Assert.equal(data.length, 6);
+  Assert.equal(data[0], 0x64);
+  Assert.equal(data[1], 0x20);
+  Assert.equal(data[2], 0x62);
+  Assert.equal(data[3], 0x65);
+  Assert.equal(data[4], 0x20);
+  Assert.equal(data[5], 0x73);
+}
+
+function init_byterange4(ch) {
+  ch.setRequestHeader("Range", "xbytes=21-", false);
+}
+
+function start_byterange4(ch) {
+  Assert.equal(ch.responseStatus, 400);
+}
+
+function init_byterange5(ch) {
+  ch.setRequestHeader("Range", "bytes=-5", false);
+}
+
+function start_byterange5(ch) {
+  Assert.equal(ch.responseStatus, 206);
+}
+
+function stop_byterange5(ch, status, data) {
+  Assert.equal(data.length, 5);
+  Assert.equal(data[0], 0x65);
+  Assert.equal(data[1], 0x65);
+  Assert.equal(data[2], 0x6e);
+  Assert.equal(data[3], 0x2e);
+  Assert.equal(data[4], 0x0a);
+}
+
+function init_byterange6(ch) {
+  ch.setRequestHeader("Range", "bytes=15-12", false);
+}
+
+function start_byterange6(ch) {
+  Assert.equal(ch.responseStatus, 200);
+}
+
+function stop_byterange6(ch, status, data) {
+  Assert.equal(data.length, 21);
+  Assert.equal(data[0], 0x54);
+  Assert.equal(data[20], 0x0a);
+}
+
+function init_byterange7(ch) {
+  ch.setRequestHeader("Range", "bytes=0-5", false);
+}
+
+function start_byterange7(ch) {
+  Assert.equal(ch.responseStatus, 206);
+  Assert.equal(ch.getResponseHeader("Content-Length"), "6");
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+  Assert.equal(ch.getResponseHeader("Content-Range"), "bytes 0-5/21");
+}
+
+function stop_byterange7(ch, status, data) {
+  Assert.equal(data.length, 6);
+  Assert.equal(data[0], 0x54);
+  Assert.equal(data[1], 0x68);
+  Assert.equal(data[2], 0x69);
+  Assert.equal(data[3], 0x73);
+  Assert.equal(data[4], 0x20);
+  Assert.equal(data[5], 0x73);
+}
+
+function init_byterange8(ch) {
+  ch.setRequestHeader("Range", "bytes=20-21", false);
+}
+
+function start_byterange8(ch) {
+  Assert.equal(ch.responseStatus, 206);
+  Assert.equal(ch.getResponseHeader("Content-Range"), "bytes 20-20/21");
+}
+
+function stop_byterange8(ch, status, data) {
+  Assert.equal(data.length, 1);
+  Assert.equal(data[0], 0x0a);
+}
+
+function init_byterange9(ch) {
+  ch.setRequestHeader("Range", "bytes=020-021", false);
+}
+
+function start_byterange9(ch) {
+  Assert.equal(ch.responseStatus, 206);
+}
+
+function stop_byterange9(ch, status, data) {
+  Assert.equal(data.length, 1);
+  Assert.equal(data[0], 0x0a);
+}
+
+function init_byterange10(ch) {
+  ch.setRequestHeader("Range", "bytes=-", false);
+}
+
+function start_byterange10(ch) {
+  Assert.equal(ch.responseStatus, 400);
+}
+
+function init_byterange11(ch) {
+  ch.setRequestHeader("Range", "bytes=-500", false);
+}
+
+function start_byterange11(ch) {
+  Assert.equal(ch.responseStatus, 206);
+}
+
+function stop_byterange11(ch, status, data) {
+  Assert.equal(data.length, 21);
+  Assert.equal(data[0], 0x54);
+  Assert.equal(data[20], 0x0a);
+}
+
+function start_byterange12(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.getResponseHeader("Content-Length"), "0");
+}
+
+function stop_byterange12(ch, status, data) {
+  Assert.equal(data.length, 0);
+}
+
+function init_byterange13(ch) {
+  ch.setRequestHeader("Range", "bytes=9999999-", false);
+}
+
+function start_byterange13(ch) {
+  Assert.equal(ch.responseStatus, 416);
+  Assert.equal(ch.getResponseHeader("X-SJS-Header"), "customized");
+}
diff --git a/netwerk/test/httpserver/test/test_cern_meta.js b/netwerk/test/httpserver/test/test_cern_meta.js
new file mode 100644
index 0000000000..3497a88ea7
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_cern_meta.js
@@ -0,0 +1,79 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// exercises support for mod_cern_meta-style header/status line modification
+var srv;
+
+ChromeUtils.defineLazyGetter(this, "PREFIX", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(PREFIX + "/test_both.html", null, start_testBoth, null),
+    new Test(
+      PREFIX + "/test_ctype_override.txt",
+      null,
+      start_test_ctype_override_txt,
+      null
+    ),
+    new Test(
+      PREFIX + "/test_status_override.html",
+      null,
+      start_test_status_override_html,
+      null
+    ),
+    new Test(
+      PREFIX + "/test_status_override_nodesc.txt",
+      null,
+      start_test_status_override_nodesc_txt,
+      null
+    ),
+    new Test(PREFIX + "/caret_test.txt^", null, start_caret_test_txt_, null),
+  ];
+});
+
+function run_test() {
+  srv = createServer();
+
+  var cernDir = do_get_file("data/cern_meta/");
+  srv.registerDirectory("/", cernDir);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// TEST DATA
+
+function start_testBoth(ch) {
+  Assert.equal(ch.responseStatus, 501);
+  Assert.equal(ch.responseStatusText, "Unimplemented");
+
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+}
+
+function start_test_ctype_override_txt(ch) {
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/html");
+}
+
+function start_test_status_override_html(ch) {
+  Assert.equal(ch.responseStatus, 404);
+  Assert.equal(ch.responseStatusText, "Can't Find This");
+}
+
+function start_test_status_override_nodesc_txt(ch) {
+  Assert.equal(ch.responseStatus, 732);
+  Assert.equal(ch.responseStatusText, "");
+}
+
+function start_caret_test_txt_(ch) {
+  Assert.equal(ch.responseStatus, 500);
+  Assert.equal(ch.responseStatusText, "This Isn't A Server Error");
+
+  Assert.equal(ch.getResponseHeader("Foo-RFC"), "3092");
+  Assert.equal(ch.getResponseHeader("Shaving-Cream-Atom"), "Illudium Phosdex");
+}
diff --git a/netwerk/test/httpserver/test/test_default_index_handler.js b/netwerk/test/httpserver/test/test_default_index_handler.js
new file mode 100644
index 0000000000..efa02cb6e3
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_default_index_handler.js
@@ -0,0 +1,248 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// checks for correct output with the default index handler, mostly to do
+// escaping checks -- highly dependent on the default index handler output
+// format
+
+var srv, dir, gDirEntries;
+
+ChromeUtils.defineLazyGetter(this, "BASE_URL", function () {
+  return "http://localhost:" + srv.identity.primaryPort + "/";
+});
+
+function run_test() {
+  createTestDirectory();
+
+  srv = createServer();
+  srv.registerDirectory("/", dir);
+
+  var nameDir = do_get_file("data/name-scheme/");
+  srv.registerDirectory("/bar/", nameDir);
+
+  srv.start(-1);
+
+  function done() {
+    do_test_pending();
+    destroyTestDirectory();
+    srv.stop(function () {
+      do_test_finished();
+    });
+  }
+
+  runHttpTests(tests, done);
+}
+
+function createTestDirectory() {
+  dir = Services.dirsvc.get("TmpD", Ci.nsIFile);
+  dir.append("index_handler_test_" + Math.random());
+  dir.createUnique(Ci.nsIFile.DIRECTORY_TYPE, 0o744);
+
+  // populate with test directories, files, etc.
+  // Files must be in expected order of display on the index page!
+
+  var files = [];
+
+  makeFile("aa_directory", true, dir, files);
+  makeFile("Ba_directory", true, dir, files);
+  makeFile("bb_directory", true, dir, files);
+  makeFile("foo", true, dir, files);
+  makeFile("a_file", false, dir, files);
+  makeFile("B_file", false, dir, files);
+  makeFile("za'z", false, dir, files);
+  makeFile("zb&z", false, dir, files);
+  makeFile("zc<q", false, dir, files);
+  makeFile('zd"q', false, dir, files);
+  makeFile("ze%g", false, dir, files);
+  makeFile("zf%200h", false, dir, files);
+  makeFile("zg>m", false, dir, files);
+
+  gDirEntries = [files];
+
+  var subdir = dir.clone();
+  subdir.append("foo");
+
+  files = [];
+
+  makeFile("aa_dir", true, subdir, files);
+  makeFile("b_dir", true, subdir, files);
+  makeFile("AA_file.txt", false, subdir, files);
+  makeFile("test.txt", false, subdir, files);
+
+  gDirEntries.push(files);
+}
+
+function destroyTestDirectory() {
+  dir.remove(true);
+}
+
+/** ***********
+ * UTILITIES *
+ *************/
+
+/** Verifies data in bytes for the trailing-caret path above. */
+function hiddenDataCheck(bytes, uri, path) {
+  var data = String.fromCharCode.apply(null, bytes);
+
+  var parser = new DOMParser();
+
+  // Note: the index format isn't XML -- it's actually HTML -- but we require
+  //       the index format also be valid XML, albeit XML without namespaces,
+  //       XML declarations, etc.  Doing this simplifies output checking.
+  try {
+    var doc = parser.parseFromString(data, "application/xml");
+  } catch (e) {
+    do_throw("document failed to parse as XML");
+  }
+
+  var body = doc.documentElement.getElementsByTagName("body");
+  Assert.equal(body.length, 1);
+  body = body[0];
+
+  // header
+  var header = body.getElementsByTagName("h1");
+  Assert.equal(header.length, 1);
+
+  Assert.equal(header[0].textContent, path);
+
+  // files
+  var lst = body.getElementsByTagName("ol");
+  Assert.equal(lst.length, 1);
+  var items = lst[0].getElementsByTagName("li");
+
+  var top = Services.io.newURI(uri);
+
+  // N.B. No ERROR_IF_SEE_THIS.txt^ file!
+  var dirEntries = [
+    { name: "file.txt", isDirectory: false },
+    { name: "SHOULD_SEE_THIS.txt^", isDirectory: false },
+  ];
+
+  for (var i = 0; i < items.length; i++) {
+    var link = items[i].childNodes[0];
+    var f = dirEntries[i];
+
+    var sep = f.isDirectory ? "/" : "";
+
+    Assert.equal(link.textContent, f.name + sep);
+
+    uri = Services.io.newURI(link.getAttribute("href"), null, top);
+    Assert.equal(decodeURIComponent(uri.pathQueryRef), path + f.name + sep);
+  }
+}
+
+/**
+ * Verifies data in bytes (an array of bytes) represents an index page for the
+ * given URI and path, which should be a page listing the given directory
+ * entries, in order.
+ *
+ * @param bytes
+ *   array of bytes representing the index page's contents
+ * @param uri
+ *   string which is the URI of the index page
+ * @param path
+ *   the path portion of uri
+ * @param dirEntries
+ *   sorted (in the manner the directory entries should be sorted) array of
+ *   objects, each of which has a name property (whose value is the file's name,
+ *   without / if it's a directory) and an isDirectory property (with expected
+ *   value)
+ */
+function dataCheck(bytes, uri, path, dirEntries) {
+  var data = String.fromCharCode.apply(null, bytes);
+
+  var parser = new DOMParser();
+
+  // Note: the index format isn't XML -- it's actually HTML -- but we require
+  //       the index format also be valid XML, albeit XML without namespaces,
+  //       XML declarations, etc.  Doing this simplifies output checking.
+  try {
+    var doc = parser.parseFromString(data, "application/xml");
+  } catch (e) {
+    do_throw("document failed to parse as XML");
+  }
+
+  var body = doc.documentElement.getElementsByTagName("body");
+  Assert.equal(body.length, 1);
+  body = body[0];
+
+  // header
+  var header = body.getElementsByTagName("h1");
+  Assert.equal(header.length, 1);
+
+  Assert.equal(header[0].textContent, path);
+
+  // files
+  var lst = body.getElementsByTagName("ol");
+  Assert.equal(lst.length, 1);
+  var items = lst[0].getElementsByTagName("li");
+  var top = Services.io.newURI(uri);
+
+  for (var i = 0; i < items.length; i++) {
+    var link = items[i].childNodes[0];
+    var f = dirEntries[i];
+
+    var sep = f.isDirectory ? "/" : "";
+
+    Assert.equal(link.textContent, f.name + sep);
+
+    uri = Services.io.newURI(link.getAttribute("href"), null, top);
+    Assert.equal(decodeURIComponent(uri.pathQueryRef), path + f.name + sep);
+  }
+}
+
+/**
+ * Create a file/directory with the given name underneath parentDir, and
+ * append an object with name/isDirectory properties to lst corresponding
+ * to it if the file/directory could be created.
+ */
+function makeFile(name, isDirectory, parentDir, lst) {
+  var type = Ci.nsIFile[isDirectory ? "DIRECTORY_TYPE" : "NORMAL_FILE_TYPE"];
+  var file = parentDir.clone();
+
+  try {
+    file.append(name);
+    file.create(type, 0o755);
+    lst.push({ name, isDirectory });
+  } catch (e) {
+    /* OS probably doesn't like file name, skip */
+  }
+}
+
+/** *******
+ * TESTS *
+ *********/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(BASE_URL, null, start, stopRootDirectory),
+    new Test(BASE_URL + "foo/", null, start, stopFooDirectory),
+    new Test(
+      BASE_URL + "bar/folder^/",
+      null,
+      start,
+      stopTrailingCaretDirectory
+    ),
+  ];
+});
+
+// check top-level directory listing
+function start(ch) {
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/html;charset=utf-8");
+}
+function stopRootDirectory(ch, status, data) {
+  dataCheck(data, BASE_URL, "/", gDirEntries[0]);
+}
+
+// check non-top-level, too
+function stopFooDirectory(ch, status, data) {
+  dataCheck(data, BASE_URL + "foo/", "/foo/", gDirEntries[1]);
+}
+
+// trailing-caret leaf with hidden files
+function stopTrailingCaretDirectory(ch, status, data) {
+  hiddenDataCheck(data, BASE_URL + "bar/folder^/", "/bar/folder^/");
+}
diff --git a/netwerk/test/httpserver/test/test_empty_body.js b/netwerk/test/httpserver/test/test_empty_body.js
new file mode 100644
index 0000000000..fa9b7cbfdc
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_empty_body.js
@@ -0,0 +1,59 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// in its original incarnation, the server didn't like empty response-bodies;
+// see the comment in _end for details
+
+var srv;
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/empty-body-unwritten",
+      null,
+      ensureEmpty,
+      null
+    ),
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/empty-body-written",
+      null,
+      ensureEmpty,
+      null
+    ),
+  ];
+});
+
+function run_test() {
+  srv = createServer();
+
+  // register a few test paths
+  srv.registerPathHandler("/empty-body-unwritten", emptyBodyUnwritten);
+  srv.registerPathHandler("/empty-body-written", emptyBodyWritten);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// TEST DATA
+
+function ensureEmpty(ch) {
+  Assert.ok(ch.contentLength == 0);
+}
+
+// PATH HANDLERS
+
+// /empty-body-unwritten
+function emptyBodyUnwritten(metadata, response) {
+  response.setStatusLine("1.1", 200, "OK");
+}
+
+// /empty-body-written
+function emptyBodyWritten(metadata, response) {
+  response.setStatusLine("1.1", 200, "OK");
+  var body = "";
+  response.bodyOutputStream.write(body, body.length);
+}
diff --git a/netwerk/test/httpserver/test/test_errorhandler_exception.js b/netwerk/test/httpserver/test/test_errorhandler_exception.js
new file mode 100644
index 0000000000..e9cdb0bf4f
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_errorhandler_exception.js
@@ -0,0 +1,95 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Request handlers may throw exceptions, and those exception should be caught
+// by the server and converted into the proper error codes.
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/throws/exception",
+      null,
+      start_throws_exception,
+      succeeded
+    ),
+    new Test(
+      "http://localhost:" +
+        srv.identity.primaryPort +
+        "/this/file/does/not/exist/and/404s",
+      null,
+      start_nonexistent_404_fails_so_400,
+      succeeded
+    ),
+    new Test(
+      "http://localhost:" +
+        srv.identity.primaryPort +
+        "/attempts/404/fails/so/400/fails/so/500s",
+      register400Handler,
+      start_multiple_exceptions_500,
+      succeeded
+    ),
+  ];
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+
+  srv.registerErrorHandler(404, throwsException);
+  srv.registerPathHandler("/throws/exception", throwsException);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// TEST DATA
+
+function checkStatusLine(
+  channel,
+  httpMaxVer,
+  httpMinVer,
+  httpCode,
+  statusText
+) {
+  Assert.equal(channel.responseStatus, httpCode);
+  Assert.equal(channel.responseStatusText, statusText);
+
+  var respMaj = {},
+    respMin = {};
+  channel.getResponseVersion(respMaj, respMin);
+  Assert.equal(respMaj.value, httpMaxVer);
+  Assert.equal(respMin.value, httpMinVer);
+}
+
+function start_throws_exception(ch) {
+  checkStatusLine(ch, 1, 1, 500, "Internal Server Error");
+}
+
+function start_nonexistent_404_fails_so_400(ch) {
+  checkStatusLine(ch, 1, 1, 400, "Bad Request");
+}
+
+function start_multiple_exceptions_500(ch) {
+  checkStatusLine(ch, 1, 1, 500, "Internal Server Error");
+}
+
+function succeeded(ch, status, data) {
+  Assert.ok(Components.isSuccessCode(status));
+}
+
+function register400Handler(ch) {
+  srv.registerErrorHandler(400, throwsException);
+}
+
+// PATH HANDLERS
+
+// /throws/exception (and also a 404 and 400 error handler)
+function throwsException(metadata, response) {
+  throw new Error("this shouldn't cause an exit...");
+  do_throw("Not reached!"); // eslint-disable-line no-unreachable
+}
diff --git a/netwerk/test/httpserver/test/test_header_array.js b/netwerk/test/httpserver/test/test_header_array.js
new file mode 100644
index 0000000000..1579c5ceeb
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_header_array.js
@@ -0,0 +1,66 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// test that special headers are sent as an array of headers with the same name
+
+var srv;
+
+function run_test() {
+  srv;
+
+  srv = createServer();
+  srv.registerPathHandler("/path-handler", pathHandler);
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+/** **********
+ * HANDLERS *
+ ************/
+
+function pathHandler(request, response) {
+  response.setHeader("Cache-Control", "no-cache", false);
+
+  response.setHeader("Proxy-Authenticate", "First line 1", true);
+  response.setHeader("Proxy-Authenticate", "Second line 1", true);
+  response.setHeader("Proxy-Authenticate", "Third line 1", true);
+
+  response.setHeader("WWW-Authenticate", "Not merged line 1", false);
+  response.setHeader("WWW-Authenticate", "Not merged line 2", true);
+
+  response.setHeader("WWW-Authenticate", "First line 2", false);
+  response.setHeader("WWW-Authenticate", "Second line 2", true);
+  response.setHeader("WWW-Authenticate", "Third line 2", true);
+
+  response.setHeader("X-Single-Header-Merge", "Single 1", true);
+  response.setHeader("X-Single-Header-Merge", "Single 2", true);
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/path-handler",
+      null,
+      check
+    ),
+  ];
+});
+
+function check(ch) {
+  var headerValue;
+
+  headerValue = ch.getResponseHeader("Proxy-Authenticate");
+  Assert.equal(headerValue, "First line 1\nSecond line 1\nThird line 1");
+  headerValue = ch.getResponseHeader("WWW-Authenticate");
+  Assert.equal(headerValue, "First line 2\nSecond line 2\nThird line 2");
+  headerValue = ch.getResponseHeader("X-Single-Header-Merge");
+  Assert.equal(headerValue, "Single 1,Single 2");
+}
diff --git a/netwerk/test/httpserver/test/test_headers.js b/netwerk/test/httpserver/test/test_headers.js
new file mode 100644
index 0000000000..8e920c6f2f
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_headers.js
@@ -0,0 +1,169 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// tests for header storage in httpd.js; nsHttpHeaders is an *internal* data
+// structure and is not to be used directly outside of httpd.js itself except
+// for testing purposes
+
+/**
+ * Ensures that a fieldname-fieldvalue combination is a valid header.
+ *
+ * @param fieldName
+ *   the name of the header
+ * @param fieldValue
+ *   the value of the header
+ * @param headers
+ *   an nsHttpHeaders object to use to check validity
+ */
+function assertValidHeader(fieldName, fieldValue, headers) {
+  try {
+    headers.setHeader(fieldName, fieldValue, false);
+  } catch (e) {
+    do_throw("Unexpected exception thrown: " + e);
+  }
+}
+
+/**
+ * Ensures that a fieldname-fieldvalue combination is not a valid header.
+ *
+ * @param fieldName
+ *   the name of the header
+ * @param fieldValue
+ *   the value of the header
+ * @param headers
+ *   an nsHttpHeaders object to use to check validity
+ */
+function assertInvalidHeader(fieldName, fieldValue, headers) {
+  try {
+    headers.setHeader(fieldName, fieldValue, false);
+    throw new Error(
+      `Setting (${fieldName}, ${fieldValue}) as header succeeded!`
+    );
+  } catch (e) {
+    if (e.result !== Cr.NS_ERROR_INVALID_ARG) {
+      do_throw("Unexpected exception thrown: " + e);
+    }
+  }
+}
+
+function run_test() {
+  testHeaderValidity();
+  testGetHeader();
+  testHeaderEnumerator();
+  testHasHeader();
+}
+
+function testHeaderValidity() {
+  var headers = new nsHttpHeaders();
+
+  assertInvalidHeader("f o", "bar", headers);
+  assertInvalidHeader("f\0n", "bar", headers);
+  assertInvalidHeader("foo:", "bar", headers);
+  assertInvalidHeader("f\\o", "bar", headers);
+  assertInvalidHeader("@xml", "bar", headers);
+  assertInvalidHeader("fiz(", "bar", headers);
+  assertInvalidHeader("HTTP/1.1", "bar", headers);
+  assertInvalidHeader('b"b', "bar", headers);
+  assertInvalidHeader("ascsd\t", "bar", headers);
+  assertInvalidHeader("{fds", "bar", headers);
+  assertInvalidHeader("baz?", "bar", headers);
+  assertInvalidHeader("a\\b\\c", "bar", headers);
+  assertInvalidHeader("\0x7F", "bar", headers);
+  assertInvalidHeader("\0x1F", "bar", headers);
+  assertInvalidHeader("f\n", "bar", headers);
+  assertInvalidHeader("foo", "b\nar", headers);
+  assertInvalidHeader("foo", "b\rar", headers);
+  assertInvalidHeader("foo", "b\0", headers);
+
+  // request splitting, fwiw -- we're actually immune to this type of attack so
+  // long as we don't implement persistent connections
+  assertInvalidHeader("f\r\nGET /badness HTTP/1.1\r\nFoo", "bar", headers);
+
+  assertValidHeader("f'", "baz", headers);
+  assertValidHeader("f`", "baz", headers);
+  assertValidHeader("f.", "baz", headers);
+  assertValidHeader("f---", "baz", headers);
+  assertValidHeader("---", "baz", headers);
+  assertValidHeader("~~~", "baz", headers);
+  assertValidHeader("~~~", "b\r\n bar", headers);
+  assertValidHeader("~~~", "b\r\n\tbar", headers);
+}
+
+function testGetHeader() {
+  var headers = new nsHttpHeaders();
+
+  headers.setHeader("Content-Type", "text/html", false);
+  var c = headers.getHeader("content-type");
+  Assert.equal(c, "text/html");
+
+  headers.setHeader("test", "FOO", false);
+  c = headers.getHeader("test");
+  Assert.equal(c, "FOO");
+
+  try {
+    headers.getHeader(":");
+    throw new Error("Failed to throw for invalid header");
+  } catch (e) {
+    if (e.result !== Cr.NS_ERROR_INVALID_ARG) {
+      do_throw("headers.getHeader(':') must throw invalid arg");
+    }
+  }
+
+  try {
+    headers.getHeader("valid");
+    throw new Error("header doesn't exist");
+  } catch (e) {
+    if (e.result !== Cr.NS_ERROR_NOT_AVAILABLE) {
+      do_throw("shouldn't be a header named 'valid' in headers!");
+    }
+  }
+}
+
+function testHeaderEnumerator() {
+  var headers = new nsHttpHeaders();
+
+  var heads = {
+    foo: "17",
+    baz: "two six niner",
+    decaf: "class Program { int .7; int main(){ .7 = 5; return 7 - .7; } }",
+  };
+
+  for (var i in heads) {
+    headers.setHeader(i, heads[i], false);
+  }
+
+  var en = headers.enumerator;
+  while (en.hasMoreElements()) {
+    var it = en.getNext().QueryInterface(Ci.nsISupportsString).data;
+    Assert.ok(it.toLowerCase() in heads);
+    delete heads[it.toLowerCase()];
+  }
+
+  if (Object.keys(heads).length) {
+    do_throw("still have properties in heads!?!?");
+  }
+}
+
+function testHasHeader() {
+  var headers = new nsHttpHeaders();
+
+  headers.setHeader("foo", "bar", false);
+  Assert.ok(headers.hasHeader("foo"));
+  Assert.ok(headers.hasHeader("fOo"));
+  Assert.ok(!headers.hasHeader("not-there"));
+
+  headers.setHeader("f`'~", "bar", false);
+  Assert.ok(headers.hasHeader("F`'~"));
+
+  try {
+    headers.hasHeader(":");
+    throw new Error("failed to throw");
+  } catch (e) {
+    if (e.result !== Cr.NS_ERROR_INVALID_ARG) {
+      do_throw(".hasHeader for an invalid name should throw");
+    }
+  }
+}
diff --git a/netwerk/test/httpserver/test/test_host.js b/netwerk/test/httpserver/test/test_host.js
new file mode 100644
index 0000000000..2f5fadde92
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_host.js
@@ -0,0 +1,608 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Tests that the scheme, host, and port of the server are correctly recorded
+ * and used in HTTP requests and responses.
+ */
+
+"use strict";
+
+const PORT = 4444;
+const FAKE_PORT_ONE = 8888;
+const FAKE_PORT_TWO = 8889;
+
+let srv, id;
+
+add_task(async function run_test1() {
+  dump("*** run_test1");
+
+  srv = createServer();
+
+  srv.registerPathHandler("/http/1.0-request", http10Request);
+  srv.registerPathHandler("/http/1.1-good-host", http11goodHost);
+  srv.registerPathHandler(
+    "/http/1.1-good-host-wacky-port",
+    http11goodHostWackyPort
+  );
+  srv.registerPathHandler("/http/1.1-ip-host", http11ipHost);
+
+  srv.start(FAKE_PORT_ONE);
+
+  id = srv.identity;
+
+  // The default location is http://localhost:PORT, where PORT is whatever you
+  // provided when you started the server.  http://127.0.0.1:PORT is also part
+  // of the default set of locations.
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "localhost");
+  Assert.equal(id.primaryPort, FAKE_PORT_ONE);
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  // This should be a nop.
+  id.add("http", "localhost", FAKE_PORT_ONE);
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "localhost");
+  Assert.equal(id.primaryPort, FAKE_PORT_ONE);
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  // Change the primary location and make sure all the getters work correctly.
+  id.setPrimary("http", "127.0.0.1", FAKE_PORT_ONE);
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "127.0.0.1");
+  Assert.equal(id.primaryPort, FAKE_PORT_ONE);
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  // Okay, now remove the primary location -- we fall back to the original
+  // location.
+  id.remove("http", "127.0.0.1", FAKE_PORT_ONE);
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "localhost");
+  Assert.equal(id.primaryPort, FAKE_PORT_ONE);
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  // You can't remove every location -- try this and the original default
+  // location will be silently readded.
+  id.remove("http", "localhost", FAKE_PORT_ONE);
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "localhost");
+  Assert.equal(id.primaryPort, FAKE_PORT_ONE);
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  // Okay, now that we've exercised that behavior, shut down the server and
+  // restart it on the correct port, to exercise port-changing behaviors at
+  // server start and stop.
+
+  await new Promise(resolve => srv.stop(resolve));
+});
+
+add_task(async function run_test_2() {
+  dump("*** run_test_2");
+
+  // Our primary location is gone because it was dependent on the port on which
+  // the server was running.
+  checkPrimariesThrow(id);
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+
+  srv.start(FAKE_PORT_TWO);
+
+  // We should have picked up http://localhost:8889 as our primary location now
+  // that we've restarted.
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "localhost");
+  Assert.equal(id.primaryPort, FAKE_PORT_TWO);
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+
+  // Now we're going to see what happens when we shut down with a primary
+  // location that wasn't a default.  That location should persist, and the
+  // default we remove should still not be present.
+  id.setPrimary("http", "example.com", FAKE_PORT_TWO);
+  Assert.ok(id.has("http", "example.com", FAKE_PORT_TWO));
+  Assert.ok(id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+  Assert.ok(id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+
+  id.remove("http", "localhost", FAKE_PORT_TWO);
+  Assert.ok(id.has("http", "example.com", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  id.remove("http", "127.0.0.1", FAKE_PORT_TWO);
+  Assert.ok(id.has("http", "example.com", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  await new Promise(resolve => srv.stop(resolve));
+});
+
+add_task(async function run_test_3() {
+  dump("*** run_test_3");
+
+  // Only the default added location disappears; any others stay around,
+  // possibly as the primary location.  We may have removed the default primary
+  // location, but the one we set manually should persist here.
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "example.com");
+  Assert.equal(id.primaryPort, FAKE_PORT_TWO);
+  Assert.ok(id.has("http", "example.com", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+
+  srv.start(PORT);
+
+  // Starting always adds HTTP entries for 127.0.0.1:port and localhost:port.
+  Assert.ok(id.has("http", "example.com", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+  Assert.ok(id.has("http", "localhost", PORT));
+  Assert.ok(id.has("http", "127.0.0.1", PORT));
+
+  // Remove the primary location we'd left set from last time.
+  id.remove("http", "example.com", FAKE_PORT_TWO);
+
+  // Default-port behavior testing requires the server responds to requests
+  // claiming to be on one such port.
+  id.add("http", "localhost", 80);
+
+  // Make sure we don't have anything lying around from running on either the
+  // first or the second port -- all we should have is our generated default,
+  // plus the additional port to test "portless" hostport variants.
+  Assert.ok(id.has("http", "localhost", 80));
+  Assert.equal(id.primaryScheme, "http");
+  Assert.equal(id.primaryHost, "localhost");
+  Assert.equal(id.primaryPort, PORT);
+  Assert.ok(id.has("http", "localhost", PORT));
+  Assert.ok(id.has("http", "127.0.0.1", PORT));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_ONE));
+  Assert.ok(!id.has("http", "example.com", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "localhost", FAKE_PORT_TWO));
+  Assert.ok(!id.has("http", "127.0.0.1", FAKE_PORT_TWO));
+
+  // Okay, finally done with identity testing.  Our primary location is the one
+  // we want it to be, so we're off!
+  await new Promise(resolve =>
+    runRawTests(tests, resolve, idx => dump(`running test no ${idx}`))
+  );
+
+  // Finally shut down the server.
+  await new Promise(resolve => srv.stop(resolve));
+});
+
+/** *******************
+ * UTILITY FUNCTIONS *
+ *********************/
+
+/**
+ * Verifies that all .primary* getters on a server identity correctly throw
+ * NS_ERROR_NOT_INITIALIZED.
+ *
+ * @param aId : nsIHttpServerIdentity
+ *   the server identity to test
+ */
+function checkPrimariesThrow(aId) {
+  let threw = false;
+  try {
+    aId.primaryScheme;
+  } catch (e) {
+    threw = e.result === Cr.NS_ERROR_NOT_INITIALIZED;
+  }
+  Assert.ok(threw);
+
+  threw = false;
+  try {
+    aId.primaryHost;
+  } catch (e) {
+    threw = e.result === Cr.NS_ERROR_NOT_INITIALIZED;
+  }
+  Assert.ok(threw);
+
+  threw = false;
+  try {
+    aId.primaryPort;
+  } catch (e) {
+    threw = e.result === Cr.NS_ERROR_NOT_INITIALIZED;
+  }
+  Assert.ok(threw);
+}
+
+/**
+ * Utility function to check for a 400 response.
+ */
+function check400(aData) {
+  let iter = LineIterator(aData);
+
+  // Status-Line
+  let { value: firstLine } = iter.next();
+  Assert.equal(firstLine.substring(0, HTTP_400_LEADER_LENGTH), HTTP_400_LEADER);
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+const HTTP_400_LEADER = "HTTP/1.1 400 ";
+const HTTP_400_LEADER_LENGTH = HTTP_400_LEADER.length;
+
+var test, data;
+var tests = [];
+
+// HTTP/1.0 request, to ensure we see our default scheme/host/port
+
+function http10Request(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine("1.0", 200, "TEST PASSED");
+}
+data = "GET /http/1.0-request HTTP/1.0\r\n\r\n";
+function check10(aData) {
+  let iter = LineIterator(aData);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.0 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  let body = [
+    "Method:  GET",
+    "Path:    /http/1.0-request",
+    "Query:   ",
+    "Version: 1.0",
+    "Scheme:  http",
+    "Host:    localhost",
+    "Port:    4444",
+  ];
+
+  expectLines(iter, body);
+}
+test = new RawTest("localhost", PORT, data, check10);
+tests.push(test);
+
+// HTTP/1.1 request, no Host header, expect a 400 response
+
+// eslint-disable-next-line no-useless-concat
+data = "GET /http/1.1-request HTTP/1.1\r\n" + "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, wrong host, expect a 400 response
+
+data =
+  // eslint-disable-next-line no-useless-concat
+  "GET /http/1.1-request HTTP/1.1\r\n" + "Host: not-localhost\r\n" + "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, wrong host/right port, expect a 400 response
+
+data =
+  "GET /http/1.1-request HTTP/1.1\r\n" +
+  "Host: not-localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, Host header has host but no port, expect a 400 response
+
+// eslint-disable-next-line no-useless-concat
+data = "GET /http/1.1-request HTTP/1.1\r\n" + "Host: 127.0.0.1\r\n" + "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, Request-URI has wrong port, expect a 400 response
+
+data =
+  "GET http://127.0.0.1/http/1.1-request HTTP/1.1\r\n" +
+  "Host: 127.0.0.1\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, Request-URI has wrong port, expect a 400 response
+
+data =
+  "GET http://localhost:31337/http/1.1-request HTTP/1.1\r\n" +
+  "Host: localhost:31337\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, Request-URI has wrong scheme, expect a 400 response
+
+data =
+  "GET https://localhost:4444/http/1.1-request HTTP/1.1\r\n" +
+  "Host: localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, correct Host header, expect handler's response
+
+function http11goodHost(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine("1.1", 200, "TEST PASSED");
+}
+data =
+  // eslint-disable-next-line no-useless-concat
+  "GET /http/1.1-good-host HTTP/1.1\r\n" + "Host: localhost:4444\r\n" + "\r\n";
+function check11goodHost(aData) {
+  let iter = LineIterator(aData);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.1 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  let body = [
+    "Method:  GET",
+    "Path:    /http/1.1-good-host",
+    "Query:   ",
+    "Version: 1.1",
+    "Scheme:  http",
+    "Host:    localhost",
+    "Port:    4444",
+  ];
+
+  expectLines(iter, body);
+}
+test = new RawTest("localhost", PORT, data, check11goodHost);
+tests.push(test);
+
+// HTTP/1.1 request, Host header is secondary identity
+
+function http11ipHost(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine("1.1", 200, "TEST PASSED");
+}
+data =
+  // eslint-disable-next-line no-useless-concat
+  "GET /http/1.1-ip-host HTTP/1.1\r\n" + "Host: 127.0.0.1:4444\r\n" + "\r\n";
+function check11ipHost(aData) {
+  let iter = LineIterator(aData);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.1 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  let body = [
+    "Method:  GET",
+    "Path:    /http/1.1-ip-host",
+    "Query:   ",
+    "Version: 1.1",
+    "Scheme:  http",
+    "Host:    127.0.0.1",
+    "Port:    4444",
+  ];
+
+  expectLines(iter, body);
+}
+test = new RawTest("localhost", PORT, data, check11ipHost);
+tests.push(test);
+
+// HTTP/1.1 request, absolute path, accurate Host header
+
+// reusing previous request handler so not defining a new one
+
+data =
+  "GET http://localhost:4444/http/1.1-good-host HTTP/1.1\r\n" +
+  "Host: localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHost);
+tests.push(test);
+
+// HTTP/1.1 request, absolute path, inaccurate Host header
+
+// reusing previous request handler so not defining a new one
+
+data =
+  "GET http://localhost:4444/http/1.1-good-host HTTP/1.1\r\n" +
+  "Host: localhost:1234\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHost);
+tests.push(test);
+
+// HTTP/1.1 request, absolute path, different inaccurate Host header
+
+// reusing previous request handler so not defining a new one
+
+data =
+  "GET http://localhost:4444/http/1.1-good-host HTTP/1.1\r\n" +
+  "Host: not-localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHost);
+tests.push(test);
+
+// HTTP/1.1 request, absolute path, yet another inaccurate Host header
+
+// reusing previous request handler so not defining a new one
+
+data =
+  "GET http://localhost:4444/http/1.1-good-host HTTP/1.1\r\n" +
+  "Host: yippity-skippity\r\n" +
+  "\r\n";
+function checkInaccurate(aData) {
+  check11goodHost(aData);
+
+  // dynamism setup
+  srv.identity.setPrimary("http", "127.0.0.1", 4444);
+}
+test = new RawTest("localhost", PORT, data, checkInaccurate);
+tests.push(test);
+
+// HTTP/1.0 request, absolute path, different inaccurate Host header
+
+// reusing previous request handler so not defining a new one
+
+data =
+  "GET /http/1.0-request HTTP/1.0\r\n" +
+  "Host: not-localhost:4444\r\n" +
+  "\r\n";
+function check10ip(aData) {
+  let iter = LineIterator(aData);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.0 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  let body = [
+    "Method:  GET",
+    "Path:    /http/1.0-request",
+    "Query:   ",
+    "Version: 1.0",
+    "Scheme:  http",
+    "Host:    127.0.0.1",
+    "Port:    4444",
+  ];
+
+  expectLines(iter, body);
+}
+test = new RawTest("localhost", PORT, data, check10ip);
+tests.push(test);
+
+// HTTP/1.1 request, Host header with implied port
+
+function http11goodHostWackyPort(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine("1.1", 200, "TEST PASSED");
+}
+data =
+  "GET /http/1.1-good-host-wacky-port HTTP/1.1\r\n" +
+  "Host: localhost\r\n" +
+  "\r\n";
+function check11goodHostWackyPort(aData) {
+  let iter = LineIterator(aData);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.1 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  let body = [
+    "Method:  GET",
+    "Path:    /http/1.1-good-host-wacky-port",
+    "Query:   ",
+    "Version: 1.1",
+    "Scheme:  http",
+    "Host:    localhost",
+    "Port:    80",
+  ];
+
+  expectLines(iter, body);
+}
+test = new RawTest("localhost", PORT, data, check11goodHostWackyPort);
+tests.push(test);
+
+// HTTP/1.1 request, Host header with wacky implied port
+
+data =
+  "GET /http/1.1-good-host-wacky-port HTTP/1.1\r\n" +
+  "Host: localhost:\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHostWackyPort);
+tests.push(test);
+
+// HTTP/1.1 request, absolute URI with implied port
+
+data =
+  "GET http://localhost/http/1.1-good-host-wacky-port HTTP/1.1\r\n" +
+  "Host: localhost\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHostWackyPort);
+tests.push(test);
+
+// HTTP/1.1 request, absolute URI with wacky implied port
+
+data =
+  "GET http://localhost:/http/1.1-good-host-wacky-port HTTP/1.1\r\n" +
+  "Host: localhost\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHostWackyPort);
+tests.push(test);
+
+// HTTP/1.1 request, absolute URI with explicit implied port, ignored Host
+
+data =
+  "GET http://localhost:80/http/1.1-good-host-wacky-port HTTP/1.1\r\n" +
+  "Host: who-cares\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHostWackyPort);
+tests.push(test);
+
+// HTTP/1.1 request, a malformed Request-URI
+
+data =
+  "GET is-this-the-real-life-is-this-just-fantasy HTTP/1.1\r\n" +
+  "Host: localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, a malformed Host header
+
+// eslint-disable-next-line no-useless-concat
+data = "GET /http/1.1-request HTTP/1.1\r\n" + "Host: la la la\r\n" + "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, a malformed Host header but absolute URI, 5.2 sez fine
+
+data =
+  "GET http://localhost:4444/http/1.1-good-host HTTP/1.1\r\n" +
+  "Host: la la la\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check11goodHost);
+tests.push(test);
+
+// HTTP/1.0 request, absolute URI, but those aren't valid in HTTP/1.0
+
+data =
+  "GET http://localhost:4444/http/1.1-request HTTP/1.0\r\n" +
+  "Host: localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, absolute URI with unrecognized host
+
+data =
+  "GET http://not-localhost:4444/http/1.1-request HTTP/1.1\r\n" +
+  "Host: not-localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
+
+// HTTP/1.1 request, absolute URI with unrecognized host (but not in Host)
+
+data =
+  "GET http://not-localhost:4444/http/1.1-request HTTP/1.1\r\n" +
+  "Host: localhost:4444\r\n" +
+  "\r\n";
+test = new RawTest("localhost", PORT, data, check400);
+tests.push(test);
diff --git a/netwerk/test/httpserver/test/test_host_identity.js b/netwerk/test/httpserver/test/test_host_identity.js
new file mode 100644
index 0000000000..1a1662d8cf
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_host_identity.js
@@ -0,0 +1,115 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Tests that the server accepts requests to custom host names.
+ * This is commonly used in tests that map custom host names to the server via
+ * a proxy e.g. by XPCShellContentUtils.createHttpServer.
+ */
+
+var srv = createServer();
+srv.start(-1);
+registerCleanupFunction(() => new Promise(resolve => srv.stop(resolve)));
+const PORT = srv.identity.primaryPort;
+srv.registerPathHandler("/dump-request", dumpRequestLines);
+
+function dumpRequestLines(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine(request.httpVersion, 200, "TEST PASSED");
+}
+
+function makeRawRequest(requestLinePath, hostHeader) {
+  return `GET ${requestLinePath} HTTP/1.1\r\nHost: ${hostHeader}\r\n\r\n`;
+}
+
+function verifyResponseHostPort(data, query, expectedHost, expectedPort) {
+  var iter = LineIterator(data);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.1 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  var body = [
+    "Method:  GET",
+    "Path:    /dump-request",
+    "Query:   " + query,
+    "Version: 1.1",
+    "Scheme:  http",
+    "Host:    " + expectedHost,
+    "Port:    " + expectedPort,
+  ];
+
+  expectLines(iter, body);
+}
+
+function runIdentityTest(host, port) {
+  srv.identity.add("http", host, port);
+
+  function checkAbsoluteRequestURI(data) {
+    verifyResponseHostPort(data, "absolute", host, port);
+  }
+  function checkHostHeader(data) {
+    verifyResponseHostPort(data, "relative", host, port);
+  }
+
+  let tests = [];
+  let test, data;
+  let hostport = `${host}:${port}`;
+  data = makeRawRequest(`http://${hostport}/dump-request?absolute`, hostport);
+  test = new RawTest("localhost", PORT, data, checkAbsoluteRequestURI);
+  tests.push(test);
+
+  data = makeRawRequest("/dump-request?relative", hostport);
+  test = new RawTest("localhost", PORT, data, checkHostHeader);
+  tests.push(test);
+  return new Promise(resolve => {
+    runRawTests(tests, resolve);
+  });
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+add_task(async function test_basic_example_com() {
+  await runIdentityTest("example.com", 1234);
+  await runIdentityTest("example.com", 5432);
+});
+
+add_task(async function test_fully_qualified_domain_name_aka_fqdn() {
+  await runIdentityTest("fully-qualified-domain-name.", 1234);
+});
+
+add_task(async function test_ipv4() {
+  await runIdentityTest("1.2.3.4", 1234);
+});
+
+add_task(async function test_ipv6() {
+  Assert.throws(
+    () => srv.identity.add("http", "[notipv6]", 1234),
+    /NS_ERROR_ILLEGAL_VALUE/,
+    "should reject invalid host, clearly not bracketed IPv6"
+  );
+  Assert.throws(
+    () => srv.identity.add("http", "[::127.0.0.1]", 1234),
+    /NS_ERROR_ILLEGAL_VALUE/,
+    "should reject non-canonical IPv6"
+  );
+  await runIdentityTest("[::123]", 1234);
+  await runIdentityTest("[1:2:3:a:b:c:d:abcd]", 1234);
+});
+
+add_task(async function test_internationalized_domain_name() {
+  Assert.throws(
+    () => srv.identity.add("http", "δοκιμή", 1234),
+    /NS_ERROR_ILLEGAL_VALUE/,
+    "should reject IDN not in punycode"
+  );
+
+  await runIdentityTest("xn--jxalpdlp", 1234);
+});
diff --git a/netwerk/test/httpserver/test/test_linedata.js b/netwerk/test/httpserver/test/test_linedata.js
new file mode 100644
index 0000000000..83fed3e8c0
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_linedata.js
@@ -0,0 +1,22 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// test that the LineData internal data structure works correctly
+
+const CR = 0x0d;
+const LF = 0x0a;
+
+function run_test() {
+  var data = new LineData();
+  data.appendBytes(["a".charCodeAt(0), CR]);
+
+  var out = { value: "" };
+  Assert.ok(!data.readLine(out));
+
+  data.appendBytes([LF]);
+  Assert.ok(data.readLine(out));
+  Assert.equal(out.value, "a");
+}
diff --git a/netwerk/test/httpserver/test/test_load_module.js b/netwerk/test/httpserver/test/test_load_module.js
new file mode 100644
index 0000000000..38c2ca4170
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_load_module.js
@@ -0,0 +1,18 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Ensure httpd.js can be imported as a module and that a server starts.
+ */
+function run_test() {
+  const { HttpServer } = ChromeUtils.importESModule(
+    "resource://testing-common/httpd.sys.mjs"
+  );
+
+  let server = new HttpServer();
+  server.start(-1);
+
+  do_test_pending();
+
+  server.stop(do_test_finished);
+}
diff --git a/netwerk/test/httpserver/test/test_name_scheme.js b/netwerk/test/httpserver/test/test_name_scheme.js
new file mode 100644
index 0000000000..4f9fefe159
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_name_scheme.js
@@ -0,0 +1,91 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// requests for files ending with a caret (^) are handled specially to enable
+// htaccess-like functionality without the need to explicitly disable display
+// of such files
+
+var srv;
+
+ChromeUtils.defineLazyGetter(this, "PREFIX", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(PREFIX + "/bar.html^", null, start_bar_html_, null),
+    new Test(PREFIX + "/foo.html^", null, start_foo_html_, null),
+    new Test(PREFIX + "/normal-file.txt", null, start_normal_file_txt, null),
+    new Test(PREFIX + "/folder^/file.txt", null, start_folder__file_txt, null),
+
+    new Test(PREFIX + "/foo/bar.html^", null, start_bar_html_, null),
+    new Test(PREFIX + "/foo/foo.html^", null, start_foo_html_, null),
+    new Test(
+      PREFIX + "/foo/normal-file.txt",
+      null,
+      start_normal_file_txt,
+      null
+    ),
+    new Test(
+      PREFIX + "/foo/folder^/file.txt",
+      null,
+      start_folder__file_txt,
+      null
+    ),
+
+    new Test(PREFIX + "/end-caret^/bar.html^", null, start_bar_html_, null),
+    new Test(PREFIX + "/end-caret^/foo.html^", null, start_foo_html_, null),
+    new Test(
+      PREFIX + "/end-caret^/normal-file.txt",
+      null,
+      start_normal_file_txt,
+      null
+    ),
+    new Test(
+      PREFIX + "/end-caret^/folder^/file.txt",
+      null,
+      start_folder__file_txt,
+      null
+    ),
+  ];
+});
+
+function run_test() {
+  srv = createServer();
+
+  // make sure underscores work in directories "mounted" in directories with
+  // folders starting with _
+  var nameDir = do_get_file("data/name-scheme/");
+  srv.registerDirectory("/", nameDir);
+  srv.registerDirectory("/foo/", nameDir);
+  srv.registerDirectory("/end-caret^/", nameDir);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// TEST DATA
+
+function start_bar_html_(ch) {
+  Assert.equal(ch.responseStatus, 200);
+
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/html");
+}
+
+function start_foo_html_(ch) {
+  Assert.equal(ch.responseStatus, 404);
+}
+
+function start_normal_file_txt(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+}
+
+function start_folder__file_txt(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.getResponseHeader("Content-Type"), "text/plain");
+}
diff --git a/netwerk/test/httpserver/test/test_processasync.js b/netwerk/test/httpserver/test/test_processasync.js
new file mode 100644
index 0000000000..321c9b086f
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_processasync.js
@@ -0,0 +1,272 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests for correct behavior of asynchronous responses.
+ */
+
+ChromeUtils.defineLazyGetter(this, "PREPATH", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+  for (var path in handlers) {
+    srv.registerPathHandler(path, handlers[path]);
+  }
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(PREPATH + "/handleSync", null, start_handleSync, null),
+    new Test(
+      PREPATH + "/handleAsync1",
+      null,
+      start_handleAsync1,
+      stop_handleAsync1
+    ),
+    new Test(
+      PREPATH + "/handleAsync2",
+      init_handleAsync2,
+      start_handleAsync2,
+      stop_handleAsync2
+    ),
+    new Test(
+      PREPATH + "/handleAsyncOrdering",
+      null,
+      null,
+      stop_handleAsyncOrdering
+    ),
+  ];
+});
+
+var handlers = {};
+
+function handleSync(request, response) {
+  response.setStatusLine(request.httpVersion, 500, "handleSync fail");
+
+  try {
+    response.finish();
+    do_throw("finish called on sync response");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_UNEXPECTED);
+  }
+
+  response.setStatusLine(request.httpVersion, 200, "handleSync pass");
+}
+handlers["/handleSync"] = handleSync;
+
+function start_handleSync(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.responseStatusText, "handleSync pass");
+}
+
+function handleAsync1(request, response) {
+  response.setStatusLine(request.httpVersion, 500, "Old status line!");
+  response.setHeader("X-Foo", "old value", false);
+
+  response.processAsync();
+
+  response.setStatusLine(request.httpVersion, 200, "New status line!");
+  response.setHeader("X-Foo", "new value", false);
+
+  response.finish();
+
+  try {
+    response.setStatusLine(request.httpVersion, 500, "Too late!");
+    do_throw("late setStatusLine didn't throw");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+  }
+
+  try {
+    response.setHeader("X-Foo", "late value", false);
+    do_throw("late setHeader didn't throw");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+  }
+
+  try {
+    response.bodyOutputStream;
+    do_throw("late bodyOutputStream get didn't throw");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+  }
+
+  try {
+    response.write("fugly");
+    do_throw("late write() didn't throw");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+  }
+}
+handlers["/handleAsync1"] = handleAsync1;
+
+function start_handleAsync1(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.responseStatusText, "New status line!");
+  Assert.equal(ch.getResponseHeader("X-Foo"), "new value");
+}
+
+function stop_handleAsync1(ch, status, data) {
+  Assert.equal(data.length, 0);
+}
+
+const startToHeaderDelay = 500;
+const startToFinishedDelay = 750;
+
+function handleAsync2(request, response) {
+  response.processAsync();
+
+  response.setStatusLine(request.httpVersion, 200, "Status line");
+  response.setHeader("X-Custom-Header", "value", false);
+
+  callLater(startToHeaderDelay, function () {
+    var preBody = "BO";
+    response.bodyOutputStream.write(preBody, preBody.length);
+
+    try {
+      response.setStatusLine(request.httpVersion, 500, "after body write");
+      do_throw("setStatusLine succeeded");
+    } catch (e) {
+      isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+
+    try {
+      response.setHeader("X-Custom-Header", "new 1", false);
+    } catch (e) {
+      isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+    }
+
+    callLater(startToFinishedDelay - startToHeaderDelay, function () {
+      var postBody = "DY";
+      response.bodyOutputStream.write(postBody, postBody.length);
+
+      response.finish();
+      response.finish(); // idempotency
+
+      try {
+        response.setStatusLine(request.httpVersion, 500, "after finish");
+      } catch (e) {
+        isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+      }
+
+      try {
+        response.setHeader("X-Custom-Header", "new 2", false);
+      } catch (e) {
+        isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+      }
+
+      try {
+        response.write("EVIL");
+      } catch (e) {
+        isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+      }
+    });
+  });
+}
+handlers["/handleAsync2"] = handleAsync2;
+
+var startTime_handleAsync2;
+
+function init_handleAsync2(ch) {
+  var now = (startTime_handleAsync2 = Date.now());
+  dumpn("*** init_HandleAsync2: start time " + now);
+}
+
+function start_handleAsync2(ch) {
+  var now = Date.now();
+  dumpn(
+    "*** start_handleAsync2: onStartRequest time " +
+      now +
+      ", " +
+      (now - startTime_handleAsync2) +
+      "ms after start time"
+  );
+  Assert.ok(now >= startTime_handleAsync2 + startToHeaderDelay);
+
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.responseStatusText, "Status line");
+  Assert.equal(ch.getResponseHeader("X-Custom-Header"), "value");
+}
+
+function stop_handleAsync2(ch, status, data) {
+  var now = Date.now();
+  dumpn(
+    "*** stop_handleAsync2: onStopRequest time " +
+      now +
+      ", " +
+      (now - startTime_handleAsync2) +
+      "ms after header time"
+  );
+  Assert.ok(now >= startTime_handleAsync2 + startToFinishedDelay);
+
+  Assert.equal(String.fromCharCode.apply(null, data), "BODY");
+}
+
+/*
+ * Tests that accessing output stream *before* calling processAsync() works
+ * correctly, sending written data immediately as it is written, not buffering
+ * until finish() is called -- which for this much data would mean we would all
+ * but certainly deadlock, since we're trying to read/write all this data in one
+ * process on a single thread.
+ */
+function handleAsyncOrdering(request, response) {
+  var out = new BinaryOutputStream(response.bodyOutputStream);
+
+  var data = [];
+  for (var i = 0; i < 65536; i++) {
+    data[i] = 0;
+  }
+  var count = 20;
+
+  var writeData = {
+    run() {
+      if (count-- === 0) {
+        response.finish();
+        return;
+      }
+
+      try {
+        out.writeByteArray(data);
+        step();
+      } catch (e) {
+        try {
+          do_throw("error writing data: " + e);
+        } finally {
+          response.finish();
+        }
+      }
+    },
+  };
+  function step() {
+    // Use gThreadManager here because it's expedient, *not* because it's
+    // intended for public use!  If you do this in client code, expect me to
+    // knowingly break your code by changing the variable name.  :-P
+    Services.tm.dispatchToMainThread(writeData);
+  }
+  step();
+  response.processAsync();
+}
+handlers["/handleAsyncOrdering"] = handleAsyncOrdering;
+
+function stop_handleAsyncOrdering(ch, status, data) {
+  Assert.equal(data.length, 20 * 65536);
+  data.forEach(function (v, index) {
+    if (v !== 0) {
+      do_throw("value " + v + " at index " + index + " should be zero");
+    }
+  });
+}
diff --git a/netwerk/test/httpserver/test/test_qi.js b/netwerk/test/httpserver/test/test_qi.js
new file mode 100644
index 0000000000..e88e53119e
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_qi.js
@@ -0,0 +1,107 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+/* eslint-disable no-control-regex */
+
+/*
+ * Verify the presence of explicit QueryInterface methods on XPCOM objects
+ * exposed by httpd.js, rather than allowing QueryInterface to be implicitly
+ * created by XPConnect.
+ */
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/test",
+      null,
+      start_test,
+      null
+    ),
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/sjs/qi.sjs",
+      null,
+      start_sjs_qi,
+      null
+    ),
+  ];
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+
+  try {
+    srv.identity.QueryInterface(Ci.nsIHttpServerIdentity);
+  } catch (e) {
+    var exstr = ("" + e).split(/[\x09\x20-\x7f\x81-\xff]+/)[0];
+    do_throw("server identity didn't QI: " + exstr);
+    return;
+  }
+
+  srv.registerPathHandler("/test", testHandler);
+  srv.registerDirectory("/", do_get_file("data/"));
+  srv.registerContentType("sjs", "sjs");
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// TEST DATA
+
+function start_test(ch) {
+  Assert.equal(ch.responseStatusText, "QI Tests Passed");
+  Assert.equal(ch.responseStatus, 200);
+}
+
+function start_sjs_qi(ch) {
+  Assert.equal(ch.responseStatusText, "SJS QI Tests Passed");
+  Assert.equal(ch.responseStatus, 200);
+}
+
+function testHandler(request, response) {
+  var exstr;
+  var qid;
+
+  response.setStatusLine(request.httpVersion, 500, "FAIL");
+
+  var passed = false;
+  try {
+    qid = request.QueryInterface(Ci.nsIHttpRequest);
+    passed = qid === request;
+  } catch (e) {
+    exstr = ("" + e).split(/[\x09\x20-\x7f\x81-\xff]+/)[0];
+    response.setStatusLine(
+      request.httpVersion,
+      500,
+      "request doesn't QI: " + exstr
+    );
+    return;
+  }
+  if (!passed) {
+    response.setStatusLine(request.httpVersion, 500, "request QI'd wrongly?");
+    return;
+  }
+
+  passed = false;
+  try {
+    qid = response.QueryInterface(Ci.nsIHttpResponse);
+    passed = qid === response;
+  } catch (e) {
+    exstr = ("" + e).split(/[\x09\x20-\x7f\x81-\xff]+/)[0];
+    response.setStatusLine(
+      request.httpVersion,
+      500,
+      "response doesn't QI: " + exstr
+    );
+    return;
+  }
+  if (!passed) {
+    response.setStatusLine(request.httpVersion, 500, "response QI'd wrongly?");
+    return;
+  }
+
+  response.setStatusLine(request.httpVersion, 200, "QI Tests Passed");
+}
diff --git a/netwerk/test/httpserver/test/test_registerdirectory.js b/netwerk/test/httpserver/test/test_registerdirectory.js
new file mode 100644
index 0000000000..84bb032efc
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_registerdirectory.js
@@ -0,0 +1,278 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// tests the registerDirectory API
+
+ChromeUtils.defineLazyGetter(this, "BASE", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+function nocache(ch) {
+  ch.loadFlags |= Ci.nsIRequest.LOAD_BYPASS_CACHE; // important!
+}
+
+function notFound(ch) {
+  Assert.equal(ch.responseStatus, 404);
+  Assert.ok(!ch.requestSucceeded);
+}
+
+function checkOverride(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.responseStatusText, "OK");
+  Assert.ok(ch.requestSucceeded);
+  Assert.equal(ch.getResponseHeader("Override-Succeeded"), "yes");
+}
+
+function check200(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(ch.responseStatusText, "OK");
+}
+
+function checkFile(ch, status, data) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.ok(ch.requestSucceeded);
+
+  var actualFile = serverBasePath.clone();
+  actualFile.append("test_registerdirectory.js");
+  Assert.equal(
+    ch.getResponseHeader("Content-Length"),
+    actualFile.fileSize.toString()
+  );
+  Assert.equal(
+    data.map(v => String.fromCharCode(v)).join(""),
+    fileContents(actualFile)
+  );
+}
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    /** *********************
+     * without a base path *
+     ***********************/
+    new Test(BASE + "/test_registerdirectory.js", nocache, notFound, null),
+
+    /** ******************
+     * with a base path *
+     ********************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        serverBasePath = testsDirectory.clone();
+        srv.registerDirectory("/", serverBasePath);
+      },
+      null,
+      checkFile
+    ),
+
+    /** ***************************
+     * without a base path again *
+     *****************************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        serverBasePath = null;
+        srv.registerDirectory("/", serverBasePath);
+      },
+      notFound,
+      null
+    ),
+
+    /** *************************
+     * registered path handler *
+     ***************************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        srv.registerPathHandler(
+          "/test_registerdirectory.js",
+          override_test_registerdirectory
+        );
+      },
+      checkOverride,
+      null
+    ),
+
+    /** **********************
+     * removed path handler *
+     ************************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function init_registerDirectory6(ch) {
+        nocache(ch);
+        srv.registerPathHandler("/test_registerdirectory.js", null);
+      },
+      notFound,
+      null
+    ),
+
+    /** ******************
+     * with a base path *
+     ********************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+
+        // set the base path again
+        serverBasePath = testsDirectory.clone();
+        srv.registerDirectory("/", serverBasePath);
+      },
+      null,
+      checkFile
+    ),
+
+    /** ***********************
+     * ...and a path handler *
+     *************************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        srv.registerPathHandler(
+          "/test_registerdirectory.js",
+          override_test_registerdirectory
+        );
+      },
+      checkOverride,
+      null
+    ),
+
+    /** **********************
+     * removed base handler *
+     ************************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        serverBasePath = null;
+        srv.registerDirectory("/", serverBasePath);
+      },
+      checkOverride,
+      null
+    ),
+
+    /** **********************
+     * removed path handler *
+     ************************/
+    new Test(
+      BASE + "/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        srv.registerPathHandler("/test_registerdirectory.js", null);
+      },
+      notFound,
+      null
+    ),
+
+    /** ***********************
+     * mapping set up, works *
+     *************************/
+    new Test(
+      BASE + "/foo/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        serverBasePath = testsDirectory.clone();
+        srv.registerDirectory("/foo/", serverBasePath);
+      },
+      check200,
+      null
+    ),
+
+    /** *******************
+     * no mapping, fails *
+     *********************/
+    new Test(
+      BASE + "/foo/test_registerdirectory.js/test_registerdirectory.js",
+      nocache,
+      notFound,
+      null
+    ),
+
+    /** ****************
+     * mapping, works *
+     ******************/
+    new Test(
+      BASE + "/foo/test_registerdirectory.js/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        srv.registerDirectory(
+          "/foo/test_registerdirectory.js/",
+          serverBasePath
+        );
+      },
+      null,
+      checkFile
+    ),
+
+    /** **********************************
+     * two mappings set up, still works *
+     ************************************/
+    new Test(BASE + "/foo/test_registerdirectory.js", nocache, null, checkFile),
+
+    /** ************************
+     * remove topmost mapping *
+     **************************/
+    new Test(
+      BASE + "/foo/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        srv.registerDirectory("/foo/", null);
+      },
+      notFound,
+      null
+    ),
+
+    /** ************************************
+     * lower mapping still present, works *
+     **************************************/
+    new Test(
+      BASE + "/foo/test_registerdirectory.js/test_registerdirectory.js",
+      nocache,
+      null,
+      checkFile
+    ),
+
+    /** *****************
+     * mapping removed *
+     *******************/
+    new Test(
+      BASE + "/foo/test_registerdirectory.js/test_registerdirectory.js",
+      function (ch) {
+        nocache(ch);
+        srv.registerDirectory("/foo/test_registerdirectory.js/", null);
+      },
+      notFound,
+      null
+    ),
+  ];
+});
+
+var srv;
+var serverBasePath;
+var testsDirectory;
+
+function run_test() {
+  testsDirectory = do_get_cwd();
+
+  srv = createServer();
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// PATH HANDLERS
+
+// override of /test_registerdirectory.js
+function override_test_registerdirectory(metadata, response) {
+  response.setStatusLine("1.1", 200, "OK");
+  response.setHeader("Override-Succeeded", "yes", false);
+
+  var body = "success!";
+  response.bodyOutputStream.write(body, body.length);
+}
diff --git a/netwerk/test/httpserver/test/test_registerfile.js b/netwerk/test/httpserver/test/test_registerfile.js
new file mode 100644
index 0000000000..9b93d62b07
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_registerfile.js
@@ -0,0 +1,44 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// tests the registerFile API
+
+ChromeUtils.defineLazyGetter(this, "BASE", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+var file = do_get_file("test_registerfile.js");
+
+function onStart(ch) {
+  Assert.equal(ch.responseStatus, 200);
+}
+
+function onStop(ch, status, data) {
+  // not sufficient for equality, but not likely to be wrong!
+  Assert.equal(data.length, file.fileSize);
+}
+
+ChromeUtils.defineLazyGetter(this, "test", function () {
+  return new Test(BASE + "/foo", null, onStart, onStop);
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+
+  try {
+    srv.registerFile("/foo", do_get_profile());
+    throw new Error("registerFile succeeded!");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_INVALID_ARG);
+  }
+
+  srv.registerFile("/foo", file);
+  srv.start(-1);
+
+  runHttpTests([test], testComplete(srv));
+}
diff --git a/netwerk/test/httpserver/test/test_registerprefix.js b/netwerk/test/httpserver/test/test_registerprefix.js
new file mode 100644
index 0000000000..5edb75225c
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_registerprefix.js
@@ -0,0 +1,130 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// tests the registerPrefixHandler API
+
+ChromeUtils.defineLazyGetter(this, "BASE", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+function nocache(ch) {
+  ch.loadFlags |= Ci.nsIRequest.LOAD_BYPASS_CACHE; // important!
+}
+
+function notFound(ch) {
+  Assert.equal(ch.responseStatus, 404);
+  Assert.ok(!ch.requestSucceeded);
+}
+
+function makeCheckOverride(magic) {
+  return function checkOverride(ch) {
+    Assert.equal(ch.responseStatus, 200);
+    Assert.equal(ch.responseStatusText, "OK");
+    Assert.ok(ch.requestSucceeded);
+    Assert.equal(ch.getResponseHeader("Override-Succeeded"), magic);
+  };
+}
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      BASE + "/prefix/dummy",
+      prefixHandler,
+      null,
+      makeCheckOverride("prefix")
+    ),
+    new Test(
+      BASE + "/prefix/dummy",
+      pathHandler,
+      null,
+      makeCheckOverride("path")
+    ),
+    new Test(
+      BASE + "/prefix/subpath/dummy",
+      longerPrefixHandler,
+      null,
+      makeCheckOverride("subpath")
+    ),
+    new Test(BASE + "/prefix/dummy", removeHandlers, null, notFound),
+    new Test(
+      BASE + "/prefix/subpath/dummy",
+      newPrefixHandler,
+      null,
+      makeCheckOverride("subpath")
+    ),
+  ];
+});
+
+/** *************************
+ * registered prefix handler *
+ ***************************/
+
+function prefixHandler(channel) {
+  nocache(channel);
+  srv.registerPrefixHandler("/prefix/", makeOverride("prefix"));
+}
+
+/** ******************************
+ * registered path handler on top *
+ ********************************/
+
+function pathHandler(channel) {
+  nocache(channel);
+  srv.registerPathHandler("/prefix/dummy", makeOverride("path"));
+}
+
+/** ********************************
+ * registered longer prefix handler *
+ **********************************/
+
+function longerPrefixHandler(channel) {
+  nocache(channel);
+  srv.registerPrefixHandler("/prefix/subpath/", makeOverride("subpath"));
+}
+
+/** **********************
+ * removed prefix handler *
+ ************************/
+
+function removeHandlers(channel) {
+  nocache(channel);
+  srv.registerPrefixHandler("/prefix/", null);
+  srv.registerPathHandler("/prefix/dummy", null);
+}
+
+/** ***************************
+ * re-register shorter handler *
+ *****************************/
+
+function newPrefixHandler(channel) {
+  nocache(channel);
+  srv.registerPrefixHandler("/prefix/", makeOverride("prefix"));
+}
+
+var srv;
+
+function run_test() {
+  // Ensure the profile exists.
+  do_get_profile();
+
+  srv = createServer();
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// PATH HANDLERS
+
+// generate an override
+function makeOverride(magic) {
+  return function override(metadata, response) {
+    response.setStatusLine("1.1", 200, "OK");
+    response.setHeader("Override-Succeeded", magic, false);
+
+    var body = "success!";
+    response.bodyOutputStream.write(body, body.length);
+  };
+}
diff --git a/netwerk/test/httpserver/test/test_request_line_split_in_two_packets.js b/netwerk/test/httpserver/test/test_request_line_split_in_two_packets.js
new file mode 100644
index 0000000000..b1d7a7d071
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_request_line_split_in_two_packets.js
@@ -0,0 +1,137 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Tests that even when an incoming request's data for the Request-Line doesn't
+ * all fit in a single onInputStreamReady notification, the request is handled
+ * properly.
+ */
+
+var srv = createServer();
+srv.start(-1);
+const PORT = srv.identity.primaryPort;
+
+function run_test() {
+  srv.registerPathHandler(
+    "/lots-of-leading-blank-lines",
+    lotsOfLeadingBlankLines
+  );
+  srv.registerPathHandler("/very-long-request-line", veryLongRequestLine);
+
+  runRawTests(tests, testComplete(srv));
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+var test, gData, str;
+var tests = [];
+
+function veryLongRequestLine(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine(request.httpVersion, 200, "TEST PASSED");
+}
+
+var reallyLong = "0123456789ABCDEF0123456789ABCDEF"; // 32
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 128
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 512
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 2048
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 8192
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 32768
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 131072
+reallyLong = reallyLong + reallyLong + reallyLong + reallyLong; // 524288
+if (reallyLong.length !== 524288) {
+  throw new TypeError("generated length not as long as expected");
+}
+str =
+  "GET /very-long-request-line?" +
+  reallyLong +
+  " HTTP/1.1\r\n" +
+  "Host: localhost:" +
+  PORT +
+  "\r\n" +
+  "\r\n";
+gData = [];
+for (let i = 0; i < str.length; i += 16384) {
+  gData.push(str.substr(i, 16384));
+}
+
+function checkVeryLongRequestLine(data) {
+  var iter = LineIterator(data);
+
+  print("data length: " + data.length);
+  print("iter object: " + iter);
+
+  // Status-Line
+  Assert.equal(iter.next().value, "HTTP/1.1 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  var body = [
+    "Method:  GET",
+    "Path:    /very-long-request-line",
+    "Query:   " + reallyLong,
+    "Version: 1.1",
+    "Scheme:  http",
+    "Host:    localhost",
+    "Port:    " + PORT,
+  ];
+
+  expectLines(iter, body);
+}
+test = new RawTest("localhost", PORT, gData, checkVeryLongRequestLine);
+tests.push(test);
+
+function lotsOfLeadingBlankLines(request, response) {
+  writeDetails(request, response);
+  response.setStatusLine(request.httpVersion, 200, "TEST PASSED");
+}
+
+var blankLines = "\r\n";
+for (let i = 0; i < 14; i++) {
+  blankLines += blankLines;
+}
+str =
+  blankLines +
+  "GET /lots-of-leading-blank-lines HTTP/1.1\r\n" +
+  "Host: localhost:" +
+  PORT +
+  "\r\n" +
+  "\r\n";
+gData = [];
+for (let i = 0; i < str.length; i += 100) {
+  gData.push(str.substr(i, 100));
+}
+
+function checkLotsOfLeadingBlankLines(data) {
+  var iter = LineIterator(data);
+
+  // Status-Line
+  print("data length: " + data.length);
+  print("iter object: " + iter);
+
+  Assert.equal(iter.next().value, "HTTP/1.1 200 TEST PASSED");
+
+  skipHeaders(iter);
+
+  // Okay, next line must be the data we expected to be written
+  var body = [
+    "Method:  GET",
+    "Path:    /lots-of-leading-blank-lines",
+    "Query:   ",
+    "Version: 1.1",
+    "Scheme:  http",
+    "Host:    localhost",
+    "Port:    " + PORT,
+  ];
+
+  expectLines(iter, body);
+}
+
+test = new RawTest("localhost", PORT, gData, checkLotsOfLeadingBlankLines);
+tests.push(test);
diff --git a/netwerk/test/httpserver/test/test_response_write.js b/netwerk/test/httpserver/test/test_response_write.js
new file mode 100644
index 0000000000..7f5837419e
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_response_write.js
@@ -0,0 +1,57 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// make sure response.write works for strings, and coerces other args to strings
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/writeString",
+      null,
+      check_1234,
+      succeeded
+    ),
+    new Test(
+      "http://localhost:" + srv.identity.primaryPort + "/writeInt",
+      null,
+      check_1234,
+      succeeded
+    ),
+  ];
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+
+  srv.registerPathHandler("/writeString", writeString);
+  srv.registerPathHandler("/writeInt", writeInt);
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+// TEST DATA
+
+function succeeded(ch, status, data) {
+  Assert.ok(Components.isSuccessCode(status));
+  Assert.equal(data.map(v => String.fromCharCode(v)).join(""), "1234");
+}
+
+function check_1234(ch) {
+  Assert.equal(ch.getResponseHeader("Content-Length"), "4");
+}
+
+// PATH HANDLERS
+
+function writeString(metadata, response) {
+  response.write("1234");
+}
+
+function writeInt(metadata, response) {
+  response.write(1234);
+}
diff --git a/netwerk/test/httpserver/test/test_seizepower.js b/netwerk/test/httpserver/test/test_seizepower.js
new file mode 100644
index 0000000000..a74054ea37
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_seizepower.js
@@ -0,0 +1,180 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests that the seizePower API works correctly.
+ */
+
+ChromeUtils.defineLazyGetter(this, "PORT", function () {
+  return srv.identity.primaryPort;
+});
+
+var srv;
+
+function run_test() {
+  Services.prefs.setBoolPref("network.proxy.allow_hijacking_localhost", true);
+  srv = createServer();
+
+  srv.registerPathHandler("/raw-data", handleRawData);
+  srv.registerPathHandler("/called-too-late", handleTooLate);
+  srv.registerPathHandler("/exceptions", handleExceptions);
+  srv.registerPathHandler("/async-seizure", handleAsyncSeizure);
+  srv.registerPathHandler("/seize-after-async", handleSeizeAfterAsync);
+
+  srv.start(-1);
+
+  runRawTests(tests, function () {
+    Services.prefs.clearUserPref("network.proxy.allow_hijacking_localhost");
+    testComplete(srv)();
+  });
+}
+
+function checkException(fun, err, msg) {
+  try {
+    fun();
+  } catch (e) {
+    if (e !== err && e.result !== err) {
+      do_throw(msg);
+    }
+    return;
+  }
+  do_throw(msg);
+}
+
+/** ***************
+ * PATH HANDLERS *
+ *****************/
+
+function handleRawData(request, response) {
+  response.seizePower();
+  response.write("Raw data!");
+  response.finish();
+}
+
+function handleTooLate(request, response) {
+  response.write("DO NOT WANT");
+  var output = response.bodyOutputStream;
+
+  response.seizePower();
+
+  if (response.bodyOutputStream !== output) {
+    response.write("bodyOutputStream changed!");
+  } else {
+    response.write("too-late passed");
+  }
+  response.finish();
+}
+
+function handleExceptions(request, response) {
+  response.seizePower();
+  checkException(
+    function () {
+      response.setStatusLine("1.0", 500, "ISE");
+    },
+    Cr.NS_ERROR_NOT_AVAILABLE,
+    "setStatusLine should throw not-available after seizePower"
+  );
+  checkException(
+    function () {
+      response.setHeader("X-Fail", "FAIL", false);
+    },
+    Cr.NS_ERROR_NOT_AVAILABLE,
+    "setHeader should throw not-available after seizePower"
+  );
+  checkException(
+    function () {
+      response.processAsync();
+    },
+    Cr.NS_ERROR_NOT_AVAILABLE,
+    "processAsync should throw not-available after seizePower"
+  );
+  var out = response.bodyOutputStream;
+  var data = "exceptions test passed";
+  out.write(data, data.length);
+  response.seizePower(); // idempotency test of seizePower
+  response.finish();
+  response.finish(); // idempotency test of finish after seizePower
+  checkException(
+    function () {
+      response.seizePower();
+    },
+    Cr.NS_ERROR_UNEXPECTED,
+    "seizePower should throw unexpected after finish"
+  );
+}
+
+function handleAsyncSeizure(request, response) {
+  response.seizePower();
+  callLater(1, function () {
+    response.write("async seizure passed");
+    response.bodyOutputStream.close();
+    callLater(1, function () {
+      response.finish();
+    });
+  });
+}
+
+function handleSeizeAfterAsync(request, response) {
+  response.setStatusLine(request.httpVersion, 200, "async seizure pass");
+  response.processAsync();
+  checkException(
+    function () {
+      response.seizePower();
+    },
+    Cr.NS_ERROR_NOT_AVAILABLE,
+    "seizePower should throw not-available after processAsync"
+  );
+  callLater(1, function () {
+    response.finish();
+  });
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new RawTest("localhost", PORT, data0, checkRawData),
+    new RawTest("localhost", PORT, data1, checkTooLate),
+    new RawTest("localhost", PORT, data2, checkExceptions),
+    new RawTest("localhost", PORT, data3, checkAsyncSeizure),
+    new RawTest("localhost", PORT, data4, checkSeizeAfterAsync),
+  ];
+});
+
+// eslint-disable-next-line no-useless-concat
+var data0 = "GET /raw-data HTTP/1.0\r\n" + "\r\n";
+function checkRawData(data) {
+  Assert.equal(data, "Raw data!");
+}
+
+// eslint-disable-next-line no-useless-concat
+var data1 = "GET /called-too-late HTTP/1.0\r\n" + "\r\n";
+function checkTooLate(data) {
+  Assert.equal(LineIterator(data).next().value, "too-late passed");
+}
+
+// eslint-disable-next-line no-useless-concat
+var data2 = "GET /exceptions HTTP/1.0\r\n" + "\r\n";
+function checkExceptions(data) {
+  Assert.equal("exceptions test passed", data);
+}
+
+// eslint-disable-next-line no-useless-concat
+var data3 = "GET /async-seizure HTTP/1.0\r\n" + "\r\n";
+function checkAsyncSeizure(data) {
+  Assert.equal(data, "async seizure passed");
+}
+
+// eslint-disable-next-line no-useless-concat
+var data4 = "GET /seize-after-async HTTP/1.0\r\n" + "\r\n";
+function checkSeizeAfterAsync(data) {
+  Assert.equal(
+    LineIterator(data).next().value,
+    "HTTP/1.0 200 async seizure pass"
+  );
+}
diff --git a/netwerk/test/httpserver/test/test_setindexhandler.js b/netwerk/test/httpserver/test/test_setindexhandler.js
new file mode 100644
index 0000000000..e65f565673
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_setindexhandler.js
@@ -0,0 +1,60 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Make sure setIndexHandler works as expected
+
+var srv, serverBasePath;
+
+function run_test() {
+  srv = createServer();
+  serverBasePath = do_get_profile();
+  srv.registerDirectory("/", serverBasePath);
+  srv.setIndexHandler(myIndexHandler);
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+ChromeUtils.defineLazyGetter(this, "URL", function () {
+  return "http://localhost:" + srv.identity.primaryPort + "/";
+});
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(URL, init, startCustomIndexHandler, stopCustomIndexHandler),
+    new Test(URL, init, startDefaultIndexHandler, stopDefaultIndexHandler),
+  ];
+});
+
+function init(ch) {
+  ch.loadFlags |= Ci.nsIRequest.LOAD_BYPASS_CACHE; // important!
+}
+function startCustomIndexHandler(ch) {
+  Assert.equal(ch.getResponseHeader("Content-Length"), "10");
+  srv.setIndexHandler(null);
+}
+function stopCustomIndexHandler(ch, status, data) {
+  Assert.ok(Components.isSuccessCode(status));
+  Assert.equal(String.fromCharCode.apply(null, data), "directory!");
+}
+
+function startDefaultIndexHandler(ch) {
+  Assert.equal(ch.responseStatus, 200);
+}
+function stopDefaultIndexHandler(ch, status, data) {
+  Assert.ok(Components.isSuccessCode(status));
+}
+
+// PATH HANDLERS
+
+function myIndexHandler(metadata, response) {
+  var dir = metadata.getProperty("directory");
+  Assert.ok(dir != null);
+  Assert.ok(dir instanceof Ci.nsIFile);
+  Assert.ok(dir.equals(serverBasePath));
+
+  response.write("directory!");
+}
diff --git a/netwerk/test/httpserver/test/test_setstatusline.js b/netwerk/test/httpserver/test/test_setstatusline.js
new file mode 100644
index 0000000000..f9cc189a68
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_setstatusline.js
@@ -0,0 +1,142 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// exercise nsIHttpResponse.setStatusLine, ensure its atomicity, and ensure the
+// specified behavior occurs if it's not called
+
+ChromeUtils.defineLazyGetter(this, "URL", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+
+  srv.registerPathHandler("/no/setstatusline", noSetstatusline);
+  srv.registerPathHandler("/http1_0", http1_0);
+  srv.registerPathHandler("/http1_1", http1_1);
+  srv.registerPathHandler("/invalidVersion", invalidVersion);
+  srv.registerPathHandler("/invalidStatus", invalidStatus);
+  srv.registerPathHandler("/invalidDescription", invalidDescription);
+  srv.registerPathHandler("/crazyCode", crazyCode);
+  srv.registerPathHandler("/nullVersion", nullVersion);
+
+  srv.start(-1);
+
+  runHttpTests(tests, testComplete(srv));
+}
+
+/** ***********
+ * UTILITIES *
+ *************/
+
+function checkStatusLine(
+  channel,
+  httpMaxVer,
+  httpMinVer,
+  httpCode,
+  statusText
+) {
+  Assert.equal(channel.responseStatus, httpCode);
+  Assert.equal(channel.responseStatusText, statusText);
+
+  var respMaj = {},
+    respMin = {};
+  channel.getResponseVersion(respMaj, respMin);
+  Assert.equal(respMaj.value, httpMaxVer);
+  Assert.equal(respMin.value, httpMinVer);
+}
+
+/** *******
+ * TESTS *
+ *********/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(URL + "/no/setstatusline", null, startNoSetStatusLine, stop),
+    new Test(URL + "/http1_0", null, startHttp1_0, stop),
+    new Test(URL + "/http1_1", null, startHttp1_1, stop),
+    new Test(URL + "/invalidVersion", null, startPassedTrue, stop),
+    new Test(URL + "/invalidStatus", null, startPassedTrue, stop),
+    new Test(URL + "/invalidDescription", null, startPassedTrue, stop),
+    new Test(URL + "/crazyCode", null, startCrazy, stop),
+    new Test(URL + "/nullVersion", null, startNullVersion, stop),
+  ];
+});
+
+// /no/setstatusline
+function noSetstatusline(metadata, response) {}
+function startNoSetStatusLine(ch) {
+  checkStatusLine(ch, 1, 1, 200, "OK");
+}
+function stop(ch, status, data) {
+  Assert.ok(Components.isSuccessCode(status));
+}
+
+// /http1_0
+function http1_0(metadata, response) {
+  response.setStatusLine("1.0", 200, "OK");
+}
+function startHttp1_0(ch) {
+  checkStatusLine(ch, 1, 0, 200, "OK");
+}
+
+// /http1_1
+function http1_1(metadata, response) {
+  response.setStatusLine("1.1", 200, "OK");
+}
+function startHttp1_1(ch) {
+  checkStatusLine(ch, 1, 1, 200, "OK");
+}
+
+// /invalidVersion
+function invalidVersion(metadata, response) {
+  try {
+    response.setStatusLine(" 1.0", 200, "FAILED");
+  } catch (e) {
+    response.setHeader("Passed", "true", false);
+  }
+}
+function startPassedTrue(ch) {
+  checkStatusLine(ch, 1, 1, 200, "OK");
+  Assert.equal(ch.getResponseHeader("Passed"), "true");
+}
+
+// /invalidStatus
+function invalidStatus(metadata, response) {
+  try {
+    response.setStatusLine("1.0", 1000, "FAILED");
+  } catch (e) {
+    response.setHeader("Passed", "true", false);
+  }
+}
+
+// /invalidDescription
+function invalidDescription(metadata, response) {
+  try {
+    response.setStatusLine("1.0", 200, "FAILED\x01");
+  } catch (e) {
+    response.setHeader("Passed", "true", false);
+  }
+}
+
+// /crazyCode
+function crazyCode(metadata, response) {
+  response.setStatusLine("1.1", 617, "Crazy");
+}
+function startCrazy(ch) {
+  checkStatusLine(ch, 1, 1, 617, "Crazy");
+}
+
+// /nullVersion
+function nullVersion(metadata, response) {
+  response.setStatusLine(null, 255, "NULL");
+}
+function startNullVersion(ch) {
+  // currently, this server implementation defaults to 1.1
+  checkStatusLine(ch, 1, 1, 255, "NULL");
+}
diff --git a/netwerk/test/httpserver/test/test_sjs.js b/netwerk/test/httpserver/test/test_sjs.js
new file mode 100644
index 0000000000..51d92ec4e0
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_sjs.js
@@ -0,0 +1,243 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// tests support for server JS-generated pages
+
+var srv = createServer();
+
+var sjs = do_get_file("data/sjs/cgi.sjs");
+// NB: The server has no state at this point -- all state is set up and torn
+//     down in the tests, because we run the same tests twice with only a
+//     different query string on the requests, followed by the oddball
+//     test that doesn't care about throwing or not.
+srv.start(-1);
+const PORT = srv.identity.primaryPort;
+
+const BASE = "http://localhost:" + PORT;
+var test;
+var tests = [];
+
+/** *******************
+ * UTILITY FUNCTIONS *
+ *********************/
+
+function bytesToString(bytes) {
+  return bytes
+    .map(function (v) {
+      return String.fromCharCode(v);
+    })
+    .join("");
+}
+
+function skipCache(ch) {
+  ch.loadFlags |= Ci.nsIRequest.LOAD_BYPASS_CACHE;
+}
+
+/** ******************
+ * DEFINE THE TESTS *
+ ********************/
+
+/**
+ * Adds the set of tests defined in here, differentiating between tests with a
+ * SJS which throws an exception and creates a server error and tests with a
+ * normal, successful SJS.
+ */
+function setupTests(throwing) {
+  const TEST_URL = BASE + "/cgi.sjs" + (throwing ? "?throw" : "");
+
+  //   registerFile with SJS => raw text
+
+  function setupFile(ch) {
+    srv.registerFile("/cgi.sjs", sjs);
+    skipCache(ch);
+  }
+
+  function verifyRawText(channel, status, bytes) {
+    dumpn(channel.originalURI.spec);
+    Assert.equal(bytesToString(bytes), fileContents(sjs));
+  }
+
+  test = new Test(TEST_URL, setupFile, null, verifyRawText);
+  tests.push(test);
+
+  //   add mapping, => interpreted
+
+  function addTypeMapping(ch) {
+    srv.registerContentType("sjs", "sjs");
+    skipCache(ch);
+  }
+
+  function checkType(ch) {
+    if (throwing) {
+      Assert.ok(!ch.requestSucceeded);
+      Assert.equal(ch.responseStatus, 500);
+    } else {
+      Assert.equal(ch.contentType, "text/plain");
+    }
+  }
+
+  function checkContents(ch, status, data) {
+    if (!throwing) {
+      Assert.equal("PASS", bytesToString(data));
+    }
+  }
+
+  test = new Test(TEST_URL, addTypeMapping, checkType, checkContents);
+  tests.push(test);
+
+  //   remove file/type mapping, map containing directory => raw text
+
+  function setupDirectoryAndRemoveType(ch) {
+    dumpn("removing type mapping");
+    srv.registerContentType("sjs", null);
+    srv.registerFile("/cgi.sjs", null);
+    srv.registerDirectory("/", sjs.parent);
+    skipCache(ch);
+  }
+
+  test = new Test(TEST_URL, setupDirectoryAndRemoveType, null, verifyRawText);
+  tests.push(test);
+
+  //   add mapping, => interpreted
+
+  function contentAndCleanup(ch, status, data) {
+    checkContents(ch, status, data);
+
+    // clean up state we've set up
+    srv.registerDirectory("/", null);
+    srv.registerContentType("sjs", null);
+  }
+
+  test = new Test(TEST_URL, addTypeMapping, checkType, contentAndCleanup);
+  tests.push(test);
+
+  // NB: No remaining state in the server right now!  If we have any here,
+  //     either the second run of tests (without ?throw) or the tests added
+  //     after the two sets will almost certainly fail.
+}
+
+/** ***************
+ * ADD THE TESTS *
+ *****************/
+
+setupTests(true);
+setupTests(false);
+
+// Test that when extension-mappings are used, the entire filename cannot be
+// treated as an extension -- there must be at least one dot for a filename to
+// match an extension.
+
+function init(ch) {
+  // clean up state we've set up
+  srv.registerDirectory("/", sjs.parent);
+  srv.registerContentType("sjs", "sjs");
+  skipCache(ch);
+}
+
+function checkNotSJS(ch, status, data) {
+  Assert.notEqual("FAIL", bytesToString(data));
+}
+
+test = new Test(BASE + "/sjs", init, null, checkNotSJS);
+tests.push(test);
+
+// Test that Range requests are passed through to the SJS file without
+// bounds checking.
+
+function rangeInit(expectedRangeHeader) {
+  return function setupRangeRequest(ch) {
+    ch.setRequestHeader("Range", expectedRangeHeader, false);
+  };
+}
+
+function checkRangeResult(ch) {
+  try {
+    var val = ch.getResponseHeader("Content-Range");
+  } catch (e) {
+    /* IDL doesn't specify a particular exception to require */
+  }
+  if (val !== undefined) {
+    do_throw(
+      "should not have gotten a Content-Range header, but got one " +
+        "with this value: " +
+        val
+    );
+  }
+  Assert.equal(200, ch.responseStatus);
+  Assert.equal("OK", ch.responseStatusText);
+}
+
+test = new Test(
+  BASE + "/range-checker.sjs",
+  rangeInit("not-a-bytes-equals-specifier"),
+  checkRangeResult,
+  null
+);
+tests.push(test);
+test = new Test(
+  BASE + "/range-checker.sjs",
+  rangeInit("bytes=-"),
+  checkRangeResult,
+  null
+);
+tests.push(test);
+test = new Test(
+  BASE + "/range-checker.sjs",
+  rangeInit("bytes=1000000-"),
+  checkRangeResult,
+  null
+);
+tests.push(test);
+test = new Test(
+  BASE + "/range-checker.sjs",
+  rangeInit("bytes=1-4"),
+  checkRangeResult,
+  null
+);
+tests.push(test);
+test = new Test(
+  BASE + "/range-checker.sjs",
+  rangeInit("bytes=-4"),
+  checkRangeResult,
+  null
+);
+tests.push(test);
+
+// One last test: for file mappings, the content-type is determined by the
+// extension of the file on the server, not by the extension of the requested
+// path.
+
+function setupFileMapping(ch) {
+  srv.registerFile("/script.html", sjs);
+}
+
+function onStart(ch) {
+  Assert.equal(ch.contentType, "text/plain");
+}
+
+function onStop(ch, status, data) {
+  Assert.equal("PASS", bytesToString(data));
+}
+
+test = new Test(BASE + "/script.html", setupFileMapping, onStart, onStop);
+tests.push(test);
+
+/** ***************
+ * RUN THE TESTS *
+ *****************/
+
+function run_test() {
+  // Test for a content-type which isn't a field-value
+  try {
+    srv.registerContentType("foo", "bar\nbaz");
+    throw new Error(
+      "this server throws on content-types which aren't field-values"
+    );
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_INVALID_ARG);
+  }
+  runHttpTests(tests, testComplete(srv));
+}
diff --git a/netwerk/test/httpserver/test/test_sjs_object_state.js b/netwerk/test/httpserver/test/test_sjs_object_state.js
new file mode 100644
index 0000000000..30c1e5c064
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_sjs_object_state.js
@@ -0,0 +1,305 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests that the object-state-preservation mechanism works correctly.
+ */
+
+ChromeUtils.defineLazyGetter(this, "PATH", function () {
+  return "http://localhost:" + srv.identity.primaryPort + "/object-state.sjs";
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+  var sjsDir = do_get_file("data/sjs/");
+  srv.registerDirectory("/", sjsDir);
+  srv.registerContentType("sjs", "sjs");
+  srv.start(-1);
+
+  do_test_pending();
+
+  new HTTPTestLoader(PATH + "?state=initial", initialStart, initialStop);
+}
+
+/** ******************
+ * OBSERVER METHODS *
+ ********************/
+
+/*
+ * In practice the current implementation will guarantee an exact ordering of
+ * all start and stop callbacks.  However, in the interests of robustness, this
+ * test will pass given any valid ordering of callbacks.  Any ordering of calls
+ * which obeys the partial ordering shown by this directed acyclic graph will be
+ * handled correctly:
+ *
+ *    initialStart
+ *         |
+ *         V
+ *  intermediateStart
+ *         |
+ *         V
+ *   intermediateStop
+ *         |        \
+ *         |         V
+ *         |      initialStop
+ *         V
+ *     triggerStart
+ *         |
+ *         V
+ *     triggerStop
+ *
+ */
+
+var initialStarted = false;
+function initialStart(ch) {
+  dumpn("*** initialStart");
+
+  if (initialStarted) {
+    do_throw("initialStart: initialStarted is true?!?!");
+  }
+
+  initialStarted = true;
+
+  new HTTPTestLoader(
+    PATH + "?state=intermediate",
+    intermediateStart,
+    intermediateStop
+  );
+}
+
+var initialStopped = false;
+function initialStop(ch, status, data) {
+  dumpn("*** initialStop");
+
+  Assert.equal(
+    data
+      .map(function (v) {
+        return String.fromCharCode(v);
+      })
+      .join(""),
+    "done"
+  );
+
+  Assert.equal(srv.getObjectState("object-state-test"), null);
+
+  if (!initialStarted) {
+    do_throw("initialStop: initialStarted is false?!?!");
+  }
+  if (initialStopped) {
+    do_throw("initialStop: initialStopped is true?!?!");
+  }
+  if (!intermediateStarted) {
+    do_throw("initialStop: intermediateStarted is false?!?!");
+  }
+  if (!intermediateStopped) {
+    do_throw("initialStop: intermediateStopped is false?!?!");
+  }
+
+  initialStopped = true;
+
+  checkForFinish();
+}
+
+var intermediateStarted = false;
+function intermediateStart(ch) {
+  dumpn("*** intermediateStart");
+
+  Assert.notEqual(srv.getObjectState("object-state-test"), null);
+
+  if (!initialStarted) {
+    do_throw("intermediateStart: initialStarted is false?!?!");
+  }
+  if (intermediateStarted) {
+    do_throw("intermediateStart: intermediateStarted is true?!?!");
+  }
+
+  intermediateStarted = true;
+}
+
+var intermediateStopped = false;
+function intermediateStop(ch, status, data) {
+  dumpn("*** intermediateStop");
+
+  Assert.equal(
+    data
+      .map(function (v) {
+        return String.fromCharCode(v);
+      })
+      .join(""),
+    "intermediate"
+  );
+
+  Assert.notEqual(srv.getObjectState("object-state-test"), null);
+
+  if (!initialStarted) {
+    do_throw("intermediateStop: initialStarted is false?!?!");
+  }
+  if (!intermediateStarted) {
+    do_throw("intermediateStop: intermediateStarted is false?!?!");
+  }
+  if (intermediateStopped) {
+    do_throw("intermediateStop: intermediateStopped is true?!?!");
+  }
+
+  intermediateStopped = true;
+
+  new HTTPTestLoader(PATH + "?state=trigger", triggerStart, triggerStop);
+}
+
+var triggerStarted = false;
+function triggerStart(ch) {
+  dumpn("*** triggerStart");
+
+  if (!initialStarted) {
+    do_throw("triggerStart: initialStarted is false?!?!");
+  }
+  if (!intermediateStarted) {
+    do_throw("triggerStart: intermediateStarted is false?!?!");
+  }
+  if (!intermediateStopped) {
+    do_throw("triggerStart: intermediateStopped is false?!?!");
+  }
+  if (triggerStarted) {
+    do_throw("triggerStart: triggerStarted is true?!?!");
+  }
+
+  triggerStarted = true;
+}
+
+var triggerStopped = false;
+function triggerStop(ch, status, data) {
+  dumpn("*** triggerStop");
+
+  Assert.equal(
+    data
+      .map(function (v) {
+        return String.fromCharCode(v);
+      })
+      .join(""),
+    "trigger"
+  );
+
+  if (!initialStarted) {
+    do_throw("triggerStop: initialStarted is false?!?!");
+  }
+  if (!intermediateStarted) {
+    do_throw("triggerStop: intermediateStarted is false?!?!");
+  }
+  if (!intermediateStopped) {
+    do_throw("triggerStop: intermediateStopped is false?!?!");
+  }
+  if (!triggerStarted) {
+    do_throw("triggerStop: triggerStarted is false?!?!");
+  }
+  if (triggerStopped) {
+    do_throw("triggerStop: triggerStopped is false?!?!");
+  }
+
+  triggerStopped = true;
+
+  checkForFinish();
+}
+
+var finished = false;
+function checkForFinish() {
+  if (finished) {
+    try {
+      do_throw("uh-oh, how are we being finished twice?!?!");
+    } finally {
+      // eslint-disable-next-line no-undef
+      quit(1);
+    }
+  }
+
+  if (triggerStopped && initialStopped) {
+    finished = true;
+    try {
+      Assert.equal(srv.getObjectState("object-state-test"), null);
+
+      if (!initialStarted) {
+        do_throw("checkForFinish: initialStarted is false?!?!");
+      }
+      if (!intermediateStarted) {
+        do_throw("checkForFinish: intermediateStarted is false?!?!");
+      }
+      if (!intermediateStopped) {
+        do_throw("checkForFinish: intermediateStopped is false?!?!");
+      }
+      if (!triggerStarted) {
+        do_throw("checkForFinish: triggerStarted is false?!?!");
+      }
+    } finally {
+      srv.stop(do_test_finished);
+    }
+  }
+}
+
+/** *******************************
+ * UTILITY OBSERVABLE URL LOADER *
+ *********************************/
+
+/** Stream listener for the channels. */
+function HTTPTestLoader(path, start, stop) {
+  /** Path to load. */
+  this._path = path;
+
+  /** Array of bytes of data in body of response. */
+  this._data = [];
+
+  /** onStartRequest callback. */
+  this._start = start;
+
+  /** onStopRequest callback. */
+  this._stop = stop;
+
+  var channel = makeChannel(path);
+  channel.asyncOpen(this);
+}
+HTTPTestLoader.prototype = {
+  onStartRequest(request) {
+    dumpn("*** HTTPTestLoader.onStartRequest for " + this._path);
+
+    var ch = request
+      .QueryInterface(Ci.nsIHttpChannel)
+      .QueryInterface(Ci.nsIHttpChannelInternal);
+
+    try {
+      try {
+        this._start(ch);
+      } catch (e) {
+        do_throw(this._path + ": error in onStartRequest: " + e);
+      }
+    } catch (e) {
+      dumpn(
+        "!!! swallowing onStartRequest exception so onStopRequest is " +
+          "called..."
+      );
+    }
+  },
+  onDataAvailable(request, inputStream, offset, count) {
+    dumpn("*** HTTPTestLoader.onDataAvailable for " + this._path);
+
+    Array.prototype.push.apply(
+      this._data,
+      makeBIS(inputStream).readByteArray(count)
+    );
+  },
+  onStopRequest(request, status) {
+    dumpn("*** HTTPTestLoader.onStopRequest for " + this._path);
+
+    var ch = request
+      .QueryInterface(Ci.nsIHttpChannel)
+      .QueryInterface(Ci.nsIHttpChannelInternal);
+
+    this._stop(ch, status, this._data);
+  },
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIStreamListener",
+    "nsIRequestObserver",
+  ]),
+};
diff --git a/netwerk/test/httpserver/test/test_sjs_state.js b/netwerk/test/httpserver/test/test_sjs_state.js
new file mode 100644
index 0000000000..4d1fc37930
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_sjs_state.js
@@ -0,0 +1,203 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// exercises the server's state-preservation API
+
+ChromeUtils.defineLazyGetter(this, "URL", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+  var sjsDir = do_get_file("data/sjs/");
+  srv.registerDirectory("/", sjsDir);
+  srv.registerContentType("sjs", "sjs");
+  srv.registerPathHandler("/path-handler", pathHandler);
+  srv.start(-1);
+
+  function done() {
+    Assert.equal(srv.getSharedState("shared-value"), "done!");
+    Assert.equal(
+      srv.getState("/path-handler", "private-value"),
+      "pathHandlerPrivate2"
+    );
+    Assert.equal(srv.getState("/state1.sjs", "private-value"), "");
+    Assert.equal(srv.getState("/state2.sjs", "private-value"), "newPrivate5");
+    do_test_pending();
+    srv.stop(function () {
+      do_test_finished();
+    });
+  }
+
+  runHttpTests(tests, done);
+}
+
+/** **********
+ * HANDLERS *
+ ************/
+
+var firstTime = true;
+
+function pathHandler(request, response) {
+  response.setHeader("Cache-Control", "no-cache", false);
+
+  response.setHeader(
+    "X-Old-Shared-Value",
+    srv.getSharedState("shared-value"),
+    false
+  );
+  response.setHeader(
+    "X-Old-Private-Value",
+    srv.getState("/path-handler", "private-value"),
+    false
+  );
+
+  var privateValue, sharedValue;
+  if (firstTime) {
+    firstTime = false;
+    privateValue = "pathHandlerPrivate";
+    sharedValue = "pathHandlerShared";
+  } else {
+    privateValue = "pathHandlerPrivate2";
+    sharedValue = "";
+  }
+
+  srv.setState("/path-handler", "private-value", privateValue);
+  srv.setSharedState("shared-value", sharedValue);
+
+  response.setHeader("X-New-Private-Value", privateValue, false);
+  response.setHeader("X-New-Shared-Value", sharedValue, false);
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  return [
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state1.sjs?" + "newShared=newShared&newPrivate=newPrivate",
+      null,
+      start_initial,
+      null
+    ),
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state1.sjs?" + "newShared=newShared2&newPrivate=newPrivate2",
+      null,
+      start_overwrite,
+      null
+    ),
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state1.sjs?" + "newShared=&newPrivate=newPrivate3",
+      null,
+      start_remove,
+      null
+    ),
+    new Test(URL + "/path-handler", null, start_handler, null),
+    new Test(URL + "/path-handler", null, start_handler_again, null),
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state2.sjs?" + "newShared=newShared4&newPrivate=newPrivate4",
+      null,
+      start_other_initial,
+      null
+    ),
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state2.sjs?" + "newShared=",
+      null,
+      start_other_remove_ignore,
+      null
+    ),
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state2.sjs?" + "newShared=newShared5&newPrivate=newPrivate5",
+      null,
+      start_other_set_new,
+      null
+    ),
+    new Test(
+      // eslint-disable-next-line no-useless-concat
+      URL + "/state1.sjs?" + "newShared=done!&newPrivate=",
+      null,
+      start_set_remove_original,
+      null
+    ),
+  ];
+});
+
+/* Hack around bug 474845 for now. */
+function getHeaderFunction(ch) {
+  function getHeader(name) {
+    try {
+      return ch.getResponseHeader(name);
+    } catch (e) {
+      if (e.result !== Cr.NS_ERROR_NOT_AVAILABLE) {
+        throw e;
+      }
+    }
+    return "";
+  }
+  return getHeader;
+}
+
+function expectValues(ch, oldShared, newShared, oldPrivate, newPrivate) {
+  var getHeader = getHeaderFunction(ch);
+
+  Assert.equal(ch.responseStatus, 200);
+  Assert.equal(getHeader("X-Old-Shared-Value"), oldShared);
+  Assert.equal(getHeader("X-New-Shared-Value"), newShared);
+  Assert.equal(getHeader("X-Old-Private-Value"), oldPrivate);
+  Assert.equal(getHeader("X-New-Private-Value"), newPrivate);
+}
+
+function start_initial(ch) {
+  dumpn("XXX start_initial");
+  expectValues(ch, "", "newShared", "", "newPrivate");
+}
+
+function start_overwrite(ch) {
+  expectValues(ch, "newShared", "newShared2", "newPrivate", "newPrivate2");
+}
+
+function start_remove(ch) {
+  expectValues(ch, "newShared2", "", "newPrivate2", "newPrivate3");
+}
+
+function start_handler(ch) {
+  expectValues(ch, "", "pathHandlerShared", "", "pathHandlerPrivate");
+}
+
+function start_handler_again(ch) {
+  expectValues(
+    ch,
+    "pathHandlerShared",
+    "",
+    "pathHandlerPrivate",
+    "pathHandlerPrivate2"
+  );
+}
+
+function start_other_initial(ch) {
+  expectValues(ch, "", "newShared4", "", "newPrivate4");
+}
+
+function start_other_remove_ignore(ch) {
+  expectValues(ch, "newShared4", "", "newPrivate4", "");
+}
+
+function start_other_set_new(ch) {
+  expectValues(ch, "", "newShared5", "newPrivate4", "newPrivate5");
+}
+
+function start_set_remove_original(ch) {
+  expectValues(ch, "newShared5", "done!", "newPrivate3", "");
+}
diff --git a/netwerk/test/httpserver/test/test_sjs_throwing_exceptions.js b/netwerk/test/httpserver/test/test_sjs_throwing_exceptions.js
new file mode 100644
index 0000000000..8610dcb7fb
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_sjs_throwing_exceptions.js
@@ -0,0 +1,73 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests that running an SJS a whole lot of times doesn't have any ill effects
+ * (like exceeding open-file limits due to not closing the SJS file each time,
+ * then preventing any file from being opened).
+ */
+
+ChromeUtils.defineLazyGetter(this, "URL", function () {
+  return "http://localhost:" + srv.identity.primaryPort;
+});
+
+var srv;
+
+function run_test() {
+  srv = createServer();
+  var sjsDir = do_get_file("data/sjs/");
+  srv.registerDirectory("/", sjsDir);
+  srv.registerContentType("sjs", "sjs");
+  srv.start(-1);
+
+  function done() {
+    do_test_pending();
+    srv.stop(function () {
+      do_test_finished();
+    });
+    Assert.equal(gStartCount, TEST_RUNS);
+    Assert.ok(lastPassed);
+  }
+
+  runHttpTests(tests, done);
+}
+
+/** *************
+ * BEGIN TESTS *
+ ***************/
+
+var gStartCount = 0;
+var lastPassed = false;
+
+// This hits the open-file limit for me on OS X; your mileage may vary.
+const TEST_RUNS = 250;
+
+ChromeUtils.defineLazyGetter(this, "tests", function () {
+  var _tests = new Array(TEST_RUNS + 1);
+  var _test = new Test(URL + "/thrower.sjs?throw", null, start_thrower);
+  for (var i = 0; i < TEST_RUNS; i++) {
+    _tests[i] = _test;
+  }
+  // ...and don't forget to stop!
+  _tests[TEST_RUNS] = new Test(URL + "/thrower.sjs", null, start_last);
+  return _tests;
+});
+
+function start_thrower(ch) {
+  Assert.equal(ch.responseStatus, 500);
+  Assert.ok(!ch.requestSucceeded);
+
+  gStartCount++;
+}
+
+function start_last(ch) {
+  Assert.equal(ch.responseStatus, 200);
+  Assert.ok(ch.requestSucceeded);
+
+  Assert.equal(ch.getResponseHeader("X-Test-Status"), "PASS");
+
+  lastPassed = true;
+}
diff --git a/netwerk/test/httpserver/test/test_start_stop.js b/netwerk/test/httpserver/test/test_start_stop.js
new file mode 100644
index 0000000000..9dcd7c673a
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_start_stop.js
@@ -0,0 +1,166 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests for correct behavior of the server start() and stop() methods.
+ */
+
+ChromeUtils.defineLazyGetter(this, "PORT", function () {
+  return srv.identity.primaryPort;
+});
+
+ChromeUtils.defineLazyGetter(this, "PREPATH", function () {
+  return "http://localhost:" + PORT;
+});
+
+var srv, srv2;
+
+function run_test() {
+  if (mozinfo.os == "win") {
+    dumpn(
+      "*** not running test_start_stop.js on Windows for now, because " +
+        "Windows is dumb"
+    );
+    return;
+  }
+
+  dumpn("*** run_test");
+
+  srv = createServer();
+  srv.start(-1);
+
+  try {
+    srv.start(PORT);
+    do_throw("starting a started server");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_ALREADY_INITIALIZED);
+  }
+
+  do_test_pending();
+  srv.stop(function () {
+    try {
+      do_test_pending();
+      run_test_2();
+    } finally {
+      do_test_finished();
+    }
+  });
+}
+
+function run_test_2() {
+  dumpn("*** run_test_2");
+
+  do_test_finished();
+
+  srv.start(PORT);
+  srv2 = createServer();
+
+  try {
+    srv2.start(PORT);
+    do_throw("two servers on one port?");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+  }
+
+  do_test_pending();
+  try {
+    srv.stop({
+      onStopped() {
+        try {
+          do_test_pending();
+          run_test_3();
+        } finally {
+          do_test_finished();
+        }
+      },
+    });
+  } catch (e) {
+    do_throw("error stopping with an object: " + e);
+  }
+}
+
+function run_test_3() {
+  dumpn("*** run_test_3");
+
+  do_test_finished();
+
+  srv.start(PORT);
+
+  do_test_pending();
+  try {
+    srv.stop().then(function () {
+      try {
+        do_test_pending();
+        run_test_4();
+      } finally {
+        do_test_finished();
+      }
+    });
+  } catch (e) {
+    do_throw("error stopping with an object: " + e);
+  }
+}
+
+function run_test_4() {
+  dumpn("*** run_test_4");
+
+  do_test_finished();
+
+  srv.registerPathHandler("/handle", handle);
+  srv.start(PORT);
+
+  // Don't rely on the exact (but implementation-constant) sequence of events
+  // as it currently exists by making either run_test_5 or serverStopped handle
+  // the final shutdown.
+  do_test_pending();
+
+  runHttpTests([new Test(PREPATH + "/handle")], run_test_5);
+}
+
+var testsComplete = false;
+
+function run_test_5() {
+  dumpn("*** run_test_5");
+
+  testsComplete = true;
+  if (stopped) {
+    do_test_finished();
+  }
+}
+
+const INTERVAL = 500;
+
+function handle(request, response) {
+  response.processAsync();
+
+  dumpn("*** stopping server...");
+  srv.stop(serverStopped);
+
+  callLater(INTERVAL, function () {
+    Assert.ok(!stopped);
+
+    callLater(INTERVAL, function () {
+      Assert.ok(!stopped);
+      response.finish();
+
+      try {
+        response.processAsync();
+        do_throw("late processAsync didn't throw?");
+      } catch (e) {
+        isException(e, Cr.NS_ERROR_UNEXPECTED);
+      }
+    });
+  });
+}
+
+var stopped = false;
+function serverStopped() {
+  dumpn("*** server really, fully shut down now");
+  stopped = true;
+  if (testsComplete) {
+    do_test_finished();
+  }
+}
diff --git a/netwerk/test/httpserver/test/test_start_stop_ipv6.js b/netwerk/test/httpserver/test/test_start_stop_ipv6.js
new file mode 100644
index 0000000000..060605d0e3
--- /dev/null
+++ b/netwerk/test/httpserver/test/test_start_stop_ipv6.js
@@ -0,0 +1,166 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Tests for correct behavior of the server start_ipv6() and stop() methods.
+ */
+
+ChromeUtils.defineLazyGetter(this, "PORT", function () {
+  return srv.identity.primaryPort;
+});
+
+ChromeUtils.defineLazyGetter(this, "PREPATH", function () {
+  return "http://localhost:" + PORT;
+});
+
+var srv, srv2;
+
+function run_test() {
+  if (mozinfo.os == "win") {
+    dumpn(
+      "*** not running test_start_stop.js on Windows for now, because " +
+        "Windows is dumb"
+    );
+    return;
+  }
+
+  dumpn("*** run_test");
+
+  srv = createServer();
+  srv.start_ipv6(-1);
+
+  try {
+    srv.start_ipv6(PORT);
+    do_throw("starting a started server");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_ALREADY_INITIALIZED);
+  }
+
+  do_test_pending();
+  srv.stop(function () {
+    try {
+      do_test_pending();
+      run_test_2();
+    } finally {
+      do_test_finished();
+    }
+  });
+}
+
+function run_test_2() {
+  dumpn("*** run_test_2");
+
+  do_test_finished();
+
+  srv.start_ipv6(PORT);
+  srv2 = createServer();
+
+  try {
+    srv2.start_ipv6(PORT);
+    do_throw("two servers on one port?");
+  } catch (e) {
+    isException(e, Cr.NS_ERROR_NOT_AVAILABLE);
+  }
+
+  do_test_pending();
+  try {
+    srv.stop({
+      onStopped() {
+        try {
+          do_test_pending();
+          run_test_3();
+        } finally {
+          do_test_finished();
+        }
+      },
+    });
+  } catch (e) {
+    do_throw("error stopping with an object: " + e);
+  }
+}
+
+function run_test_3() {
+  dumpn("*** run_test_3");
+
+  do_test_finished();
+
+  srv.start_ipv6(PORT);
+
+  do_test_pending();
+  try {
+    srv.stop().then(function () {
+      try {
+        do_test_pending();
+        run_test_4();
+      } finally {
+        do_test_finished();
+      }
+    });
+  } catch (e) {
+    do_throw("error stopping with an object: " + e);
+  }
+}
+
+function run_test_4() {
+  dumpn("*** run_test_4");
+
+  do_test_finished();
+
+  srv.registerPathHandler("/handle", handle);
+  srv.start_ipv6(PORT);
+
+  // Don't rely on the exact (but implementation-constant) sequence of events
+  // as it currently exists by making either run_test_5 or serverStopped handle
+  // the final shutdown.
+  do_test_pending();
+
+  runHttpTests([new Test(PREPATH + "/handle")], run_test_5);
+}
+
+var testsComplete = false;
+
+function run_test_5() {
+  dumpn("*** run_test_5");
+
+  testsComplete = true;
+  if (stopped) {
+    do_test_finished();
+  }
+}
+
+const INTERVAL = 500;
+
+function handle(request, response) {
+  response.processAsync();
+
+  dumpn("*** stopping server...");
+  srv.stop(serverStopped);
+
+  callLater(INTERVAL, function () {
+    Assert.ok(!stopped);
+
+    callLater(INTERVAL, function () {
+      Assert.ok(!stopped);
+      response.finish();
+
+      try {
+        response.processAsync();
+        do_throw("late processAsync didn't throw?");
+      } catch (e) {
+        isException(e, Cr.NS_ERROR_UNEXPECTED);
+      }
+    });
+  });
+}
+
+var stopped = false;
+function serverStopped() {
+  dumpn("*** server really, fully shut down now");
+  stopped = true;
+  if (testsComplete) {
+    do_test_finished();
+  }
+}
diff --git a/netwerk/test/httpserver/test/xpcshell.toml b/netwerk/test/httpserver/test/xpcshell.toml
new file mode 100644
index 0000000000..0a687e0363
--- /dev/null
+++ b/netwerk/test/httpserver/test/xpcshell.toml
@@ -0,0 +1,68 @@
+[DEFAULT]
+head = "head_utils.js"
+support-files = ["data/**"]
+
+["test_async_response_sending.js"]
+
+["test_basic_functionality.js"]
+
+["test_body_length.js"]
+
+["test_byte_range.js"]
+
+["test_cern_meta.js"]
+
+["test_default_index_handler.js"]
+
+["test_empty_body.js"]
+
+["test_errorhandler_exception.js"]
+
+["test_header_array.js"]
+
+["test_headers.js"]
+
+["test_host.js"]
+skip-if = ["os == 'mac'"]
+run-sequentially = "Reusing same server on different specific ports."
+
+["test_host_identity.js"]
+
+["test_linedata.js"]
+
+["test_load_module.js"]
+
+["test_name_scheme.js"]
+
+["test_processasync.js"]
+
+["test_qi.js"]
+
+["test_registerdirectory.js"]
+
+["test_registerfile.js"]
+
+["test_registerprefix.js"]
+
+["test_request_line_split_in_two_packets.js"]
+
+["test_response_write.js"]
+
+["test_seizepower.js"]
+skip-if = ["os == 'mac' && socketprocess_networking"]
+
+["test_setindexhandler.js"]
+
+["test_setstatusline.js"]
+
+["test_sjs.js"]
+
+["test_sjs_object_state.js"]
+
+["test_sjs_state.js"]
+
+["test_sjs_throwing_exceptions.js"]
+
+["test_start_stop.js"]
+
+["test_start_stop_ipv6.js"]