Adding upstream version 86.0.1.upstream/86.0.1upstream

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

1 files changed, 717 insertions, 0 deletions

diff --git a/toolkit/modules/subprocess/subprocess_common.jsm b/toolkit/modules/subprocess/subprocess_common.jsm
new file mode 100644
index 0000000000..1b0ec5fa4d
--- /dev/null
+++ b/toolkit/modules/subprocess/subprocess_common.jsm
@@ -0,0 +1,717 @@
+/* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set sts=2 sw=2 et tw=80: */
+/* 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/. */
+"use strict";
+
+/* eslint-disable mozilla/balanced-listeners */
+
+const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
+
+ChromeUtils.defineModuleGetter(
+  this,
+  "AsyncShutdown",
+  "resource://gre/modules/AsyncShutdown.jsm"
+);
+ChromeUtils.defineModuleGetter(
+  this,
+  "setTimeout",
+  "resource://gre/modules/Timer.jsm"
+);
+
+Services.scriptloader.loadSubScript(
+  "resource://gre/modules/subprocess/subprocess_shared.js",
+  this
+);
+
+/* global SubprocessConstants */
+var EXPORTED_SYMBOLS = ["BaseProcess", "PromiseWorker", "SubprocessConstants"];
+
+const BUFFER_SIZE = 32768;
+
+let nextResponseId = 0;
+
+/**
+ * Wraps a ChromeWorker so that messages sent to it return a promise which
+ * resolves when the message has been received and the operation it triggers is
+ * complete.
+ */
+class PromiseWorker extends ChromeWorker {
+  constructor(url) {
+    super(url);
+
+    this.listeners = new Map();
+    this.pendingResponses = new Map();
+
+    this.addListener("close", this.onClose.bind(this));
+    this.addListener("failure", this.onFailure.bind(this));
+    this.addListener("success", this.onSuccess.bind(this));
+    this.addListener("debug", this.onDebug.bind(this));
+
+    this.addEventListener("message", this.onmessage);
+
+    this.shutdown = this.shutdown.bind(this);
+    AsyncShutdown.webWorkersShutdown.addBlocker(
+      "Subprocess.jsm: Shut down IO worker",
+      this.shutdown
+    );
+  }
+
+  onClose() {
+    AsyncShutdown.webWorkersShutdown.removeBlocker(this.shutdown);
+  }
+
+  shutdown() {
+    return this.call("shutdown", []);
+  }
+
+  /**
+   * Adds a listener for the given message from the worker. Any message received
+   * from the worker with a `data.msg` property matching the given `msg`
+   * parameter are passed to the given listener.
+   *
+   * @param {string} msg
+   *        The message to listen for.
+   * @param {function(Event)} listener
+   *        The listener to call when matching messages are received.
+   */
+  addListener(msg, listener) {
+    if (!this.listeners.has(msg)) {
+      this.listeners.set(msg, new Set());
+    }
+    this.listeners.get(msg).add(listener);
+  }
+
+  /**
+   * Removes the given message listener.
+   *
+   * @param {string} msg
+   *        The message to stop listening for.
+   * @param {function(Event)} listener
+   *        The listener to remove.
+   */
+  removeListener(msg, listener) {
+    let listeners = this.listeners.get(msg);
+    if (listeners) {
+      listeners.delete(listener);
+
+      if (!listeners.size) {
+        this.listeners.delete(msg);
+      }
+    }
+  }
+
+  onmessage(event) {
+    let { msg } = event.data;
+    let listeners = this.listeners.get(msg) || new Set();
+
+    for (let listener of listeners) {
+      try {
+        listener(event.data);
+      } catch (e) {
+        Cu.reportError(e);
+      }
+    }
+  }
+
+  /**
+   * Called when a message sent to the worker has failed, and rejects its
+   * corresponding promise.
+   *
+   * @private
+   */
+  onFailure({ msgId, error }) {
+    this.pendingResponses.get(msgId).reject(error);
+    this.pendingResponses.delete(msgId);
+  }
+
+  /**
+   * Called when a message sent to the worker has succeeded, and resolves its
+   * corresponding promise.
+   *
+   * @private
+   */
+  onSuccess({ msgId, data }) {
+    this.pendingResponses.get(msgId).resolve(data);
+    this.pendingResponses.delete(msgId);
+  }
+
+  onDebug({ message }) {
+    dump(`Worker debug: ${message}\n`);
+  }
+
+  /**
+   * Calls the given method in the worker, and returns a promise which resolves
+   * or rejects when the method has completed.
+   *
+   * @param {string} method
+   *        The name of the method to call.
+   * @param {Array} args
+   *        The arguments to pass to the method.
+   * @param {Array} [transferList]
+   *        A list of objects to transfer to the worker, rather than cloning.
+   * @returns {Promise}
+   */
+  call(method, args, transferList = []) {
+    let msgId = nextResponseId++;
+
+    return new Promise((resolve, reject) => {
+      this.pendingResponses.set(msgId, { resolve, reject });
+
+      let message = {
+        msg: method,
+        msgId,
+        args,
+      };
+
+      this.postMessage(message, transferList);
+    });
+  }
+}
+
+/**
+ * Represents an input or output pipe connected to a subprocess.
+ *
+ * @property {integer} fd
+ *           The file descriptor number of the pipe on the child process's side.
+ *           @readonly
+ */
+class Pipe {
+  /**
+   * @param {Process} process
+   *        The child process that this pipe is connected to.
+   * @param {integer} fd
+   *        The file descriptor number of the pipe on the child process's side.
+   * @param {integer} id
+   *        The internal ID of the pipe, which ties it to the corresponding Pipe
+   *        object on the Worker side.
+   */
+  constructor(process, fd, id) {
+    this.id = id;
+    this.fd = fd;
+    this.processId = process.id;
+    this.worker = process.worker;
+
+    /**
+     * @property {boolean} closed
+     *           True if the file descriptor has been closed, and can no longer
+     *           be read from or written to. Pending IO operations may still
+     *           complete, but new operations may not be initiated.
+     *           @readonly
+     */
+    this.closed = false;
+  }
+
+  /**
+   * Closes the end of the pipe which belongs to this process.
+   *
+   * @param {boolean} force
+   *        If true, the pipe is closed immediately, regardless of any pending
+   *        IO operations. If false, the pipe is closed after any existing
+   *        pending IO operations have completed.
+   * @returns {Promise<object>}
+   *          Resolves to an object with no properties once the pipe has been
+   *          closed.
+   */
+  close(force = false) {
+    this.closed = true;
+    return this.worker.call("close", [this.id, force]);
+  }
+}
+
+/**
+ * Represents an output-only pipe, to which data may be written.
+ */
+class OutputPipe extends Pipe {
+  constructor(...args) {
+    super(...args);
+
+    this.encoder = new TextEncoder();
+  }
+
+  /**
+   * Writes the given data to the stream.
+   *
+   * When given an array buffer or typed array, ownership of the buffer is
+   * transferred to the IO worker, and it may no longer be used from this
+   * thread.
+   *
+   * @param {ArrayBuffer|TypedArray|string} buffer
+   *        Data to write to the stream.
+   * @returns {Promise<object>}
+   *          Resolves to an object with a `bytesWritten` property, containing
+   *          the number of bytes successfully written, once the operation has
+   *          completed.
+   *
+   * @rejects {object}
+   *          May be rejected with an Error object, or an object with similar
+   *          properties. The object will include an `errorCode` property with
+   *          one of the following values if it was rejected for the
+   *          corresponding reason:
+   *
+   *            - Subprocess.ERROR_END_OF_FILE: The pipe was closed before
+   *              all of the data in `buffer` could be written to it.
+   */
+  write(buffer) {
+    if (typeof buffer === "string") {
+      buffer = this.encoder.encode(buffer);
+    }
+
+    if (Cu.getClassName(buffer, true) !== "ArrayBuffer") {
+      if (buffer.byteLength === buffer.buffer.byteLength) {
+        buffer = buffer.buffer;
+      } else {
+        buffer = buffer.buffer.slice(
+          buffer.byteOffset,
+          buffer.byteOffset + buffer.byteLength
+        );
+      }
+    }
+
+    let args = [this.id, buffer];
+
+    return this.worker.call("write", args, [buffer]);
+  }
+}
+
+/**
+ * Represents an input-only pipe, from which data may be read.
+ */
+class InputPipe extends Pipe {
+  constructor(...args) {
+    super(...args);
+
+    this.buffers = [];
+
+    /**
+     * @property {integer} dataAvailable
+     *           The number of readable bytes currently stored in the input
+     *           buffer.
+     *           @readonly
+     */
+    this.dataAvailable = 0;
+
+    this.decoder = new TextDecoder();
+
+    this.pendingReads = [];
+
+    this._pendingBufferRead = null;
+
+    this.fillBuffer();
+  }
+
+  /**
+   * @property {integer} bufferSize
+   *           The current size of the input buffer. This varies depending on
+   *           the size of pending read operations.
+   *           @readonly
+   */
+  get bufferSize() {
+    if (this.pendingReads.length) {
+      return Math.max(this.pendingReads[0].length, BUFFER_SIZE);
+    }
+    return BUFFER_SIZE;
+  }
+
+  /**
+   * Attempts to fill the input buffer.
+   *
+   * @private
+   */
+  fillBuffer() {
+    let dataWanted = this.bufferSize - this.dataAvailable;
+
+    if (!this._pendingBufferRead && dataWanted > 0) {
+      this._pendingBufferRead = this._read(dataWanted);
+
+      this._pendingBufferRead.then(result => {
+        this._pendingBufferRead = null;
+
+        if (result) {
+          this.onInput(result.buffer);
+
+          this.fillBuffer();
+        }
+      });
+    }
+  }
+
+  _read(size) {
+    let args = [this.id, size];
+
+    return this.worker.call("read", args).catch(e => {
+      this.closed = true;
+
+      for (let { length, resolve, reject } of this.pendingReads.splice(0)) {
+        if (
+          length === null &&
+          e.errorCode === SubprocessConstants.ERROR_END_OF_FILE
+        ) {
+          resolve(new ArrayBuffer(0));
+        } else {
+          reject(e);
+        }
+      }
+    });
+  }
+
+  /**
+   * Adds the given data to the end of the input buffer.
+   *
+   * @param {ArrayBuffer} buffer
+   *        An input buffer to append to the current buffered input.
+   * @private
+   */
+  onInput(buffer) {
+    this.buffers.push(buffer);
+    this.dataAvailable += buffer.byteLength;
+    this.checkPendingReads();
+  }
+
+  /**
+   * Checks the topmost pending read operations and fulfills as many as can be
+   * filled from the current input buffer.
+   *
+   * @private
+   */
+  checkPendingReads() {
+    this.fillBuffer();
+
+    let reads = this.pendingReads;
+    while (
+      reads.length &&
+      this.dataAvailable &&
+      reads[0].length <= this.dataAvailable
+    ) {
+      let pending = this.pendingReads.shift();
+
+      let length = pending.length || this.dataAvailable;
+
+      let result;
+      let byteLength = this.buffers[0].byteLength;
+      if (byteLength == length) {
+        result = this.buffers.shift();
+      } else if (byteLength > length) {
+        let buffer = this.buffers[0];
+
+        this.buffers[0] = buffer.slice(length);
+        result = ArrayBuffer.transfer(buffer, length);
+      } else {
+        result = ArrayBuffer.transfer(this.buffers.shift(), length);
+        let u8result = new Uint8Array(result);
+
+        while (byteLength < length) {
+          let buffer = this.buffers[0];
+          let u8buffer = new Uint8Array(buffer);
+
+          let remaining = length - byteLength;
+
+          if (buffer.byteLength <= remaining) {
+            this.buffers.shift();
+
+            u8result.set(u8buffer, byteLength);
+          } else {
+            this.buffers[0] = buffer.slice(remaining);
+
+            u8result.set(u8buffer.subarray(0, remaining), byteLength);
+          }
+
+          byteLength += Math.min(buffer.byteLength, remaining);
+        }
+      }
+
+      this.dataAvailable -= result.byteLength;
+      pending.resolve(result);
+    }
+  }
+
+  /**
+   * Reads exactly `length` bytes of binary data from the input stream, or, if
+   * length is not provided, reads the first chunk of data to become available.
+   * In the latter case, returns an empty array buffer on end of file.
+   *
+   * The read operation will not complete until enough data is available to
+   * fulfill the request. If the pipe closes without enough available data to
+   * fulfill the read, the operation fails, and any remaining buffered data is
+   * lost.
+   *
+   * @param {integer} [length]
+   *        The number of bytes to read.
+   * @returns {Promise<ArrayBuffer>}
+   *
+   * @rejects {object}
+   *          May be rejected with an Error object, or an object with similar
+   *          properties. The object will include an `errorCode` property with
+   *          one of the following values if it was rejected for the
+   *          corresponding reason:
+   *
+   *            - Subprocess.ERROR_END_OF_FILE: The pipe was closed before
+   *              enough input could be read to satisfy the request.
+   */
+  read(length = null) {
+    if (length !== null && !(Number.isInteger(length) && length >= 0)) {
+      throw new RangeError("Length must be a non-negative integer");
+    }
+
+    if (length == 0) {
+      return Promise.resolve(new ArrayBuffer(0));
+    }
+
+    return new Promise((resolve, reject) => {
+      this.pendingReads.push({ length, resolve, reject });
+      this.checkPendingReads();
+    });
+  }
+
+  /**
+   * Reads exactly `length` bytes from the input stream, and parses them as
+   * UTF-8 JSON data.
+   *
+   * @param {integer} length
+   *        The number of bytes to read.
+   * @returns {Promise<object>}
+   *
+   * @rejects {object}
+   *          May be rejected with an Error object, or an object with similar
+   *          properties. The object will include an `errorCode` property with
+   *          one of the following values if it was rejected for the
+   *          corresponding reason:
+   *
+   *            - Subprocess.ERROR_END_OF_FILE: The pipe was closed before
+   *              enough input could be read to satisfy the request.
+   *            - Subprocess.ERROR_INVALID_JSON: The data read from the pipe
+   *              could not be parsed as a valid JSON string.
+   */
+  readJSON(length) {
+    if (!Number.isInteger(length) || length <= 0) {
+      throw new RangeError("Length must be a positive integer");
+    }
+
+    return this.readString(length).then(string => {
+      try {
+        return JSON.parse(string);
+      } catch (e) {
+        e.errorCode = SubprocessConstants.ERROR_INVALID_JSON;
+        throw e;
+      }
+    });
+  }
+
+  /**
+   * Reads a chunk of UTF-8 data from the input stream, and converts it to a
+   * JavaScript string.
+   *
+   * If `length` is provided, reads exactly `length` bytes. Otherwise, reads the
+   * first chunk of data to become available, and returns an empty string on end
+   * of file. In the latter case, the chunk is decoded in streaming mode, and
+   * any incomplete UTF-8 sequences at the end of a chunk are returned at the
+   * start of a subsequent read operation.
+   *
+   * @param {integer} [length]
+   *        The number of bytes to read.
+   * @param {object} [options]
+   *        An options object as expected by TextDecoder.decode.
+   * @returns {Promise<string>}
+   *
+   * @rejects {object}
+   *          May be rejected with an Error object, or an object with similar
+   *          properties. The object will include an `errorCode` property with
+   *          one of the following values if it was rejected for the
+   *          corresponding reason:
+   *
+   *            - Subprocess.ERROR_END_OF_FILE: The pipe was closed before
+   *              enough input could be read to satisfy the request.
+   */
+  readString(length = null, options = { stream: length === null }) {
+    if (length !== null && !(Number.isInteger(length) && length >= 0)) {
+      throw new RangeError("Length must be a non-negative integer");
+    }
+
+    return this.read(length).then(buffer => {
+      return this.decoder.decode(buffer, options);
+    });
+  }
+
+  /**
+   * Reads 4 bytes from the input stream, and parses them as an unsigned
+   * integer, in native byte order.
+   *
+   * @returns {Promise<integer>}
+   *
+   * @rejects {object}
+   *          May be rejected with an Error object, or an object with similar
+   *          properties. The object will include an `errorCode` property with
+   *          one of the following values if it was rejected for the
+   *          corresponding reason:
+   *
+   *            - Subprocess.ERROR_END_OF_FILE: The pipe was closed before
+   *              enough input could be read to satisfy the request.
+   */
+  readUint32() {
+    return this.read(4).then(buffer => {
+      return new Uint32Array(buffer)[0];
+    });
+  }
+}
+
+/**
+ * @class Process
+ * @extends BaseProcess
+ */
+
+/**
+ * Represents a currently-running process, and allows interaction with it.
+ */
+class BaseProcess {
+  /**
+   * @param {PromiseWorker} worker
+   *        The worker instance which owns the process.
+   * @param {integer} processId
+   *        The internal ID of the Process object, which ties it to the
+   *        corresponding process on the Worker side.
+   * @param {integer[]} fds
+   *        An array of internal Pipe IDs, one for each standard file descriptor
+   *        in the child process.
+   * @param {integer} pid
+   *        The operating system process ID of the process.
+   */
+  constructor(worker, processId, fds, pid) {
+    this.id = processId;
+    this.worker = worker;
+
+    /**
+     * @property {integer} pid
+     *           The process ID of the process, assigned by the operating system.
+     *           @readonly
+     */
+    this.pid = pid;
+
+    this.exitCode = null;
+
+    this.exitPromise = new Promise(resolve => {
+      this.worker.call("wait", [this.id]).then(({ exitCode }) => {
+        resolve(Object.freeze({ exitCode }));
+        this.exitCode = exitCode;
+      });
+    });
+
+    if (fds[0] !== undefined) {
+      /**
+       * @property {OutputPipe} stdin
+       *           A Pipe object which allows writing to the process's standard
+       *           input.
+       *           @readonly
+       */
+      this.stdin = new OutputPipe(this, 0, fds[0]);
+    }
+    if (fds[1] !== undefined) {
+      /**
+       * @property {InputPipe} stdout
+       *           A Pipe object which allows reading from the process's standard
+       *           output.
+       *           @readonly
+       */
+      this.stdout = new InputPipe(this, 1, fds[1]);
+    }
+    if (fds[2] !== undefined) {
+      /**
+       * @property {InputPipe} [stderr]
+       *           An optional Pipe object which allows reading from the
+       *           process's standard error output.
+       *           @readonly
+       */
+      this.stderr = new InputPipe(this, 2, fds[2]);
+    }
+  }
+
+  /**
+   * Spawns a process, and resolves to a BaseProcess instance on success.
+   *
+   * @param {object} options
+   *        An options object as passed to `Subprocess.call`.
+   *
+   * @returns {Promise<BaseProcess>}
+   */
+  static create(options) {
+    let worker = this.getWorker();
+
+    return worker.call("spawn", [options]).then(({ processId, fds, pid }) => {
+      return new this(worker, processId, fds, pid);
+    });
+  }
+
+  static get WORKER_URL() {
+    throw new Error("Not implemented");
+  }
+
+  static get WorkerClass() {
+    return PromiseWorker;
+  }
+
+  /**
+   * Gets the current subprocess worker, or spawns a new one if it does not
+   * currently exist.
+   *
+   * @returns {PromiseWorker}
+   */
+  static getWorker() {
+    if (!this._worker) {
+      this._worker = new this.WorkerClass(this.WORKER_URL);
+    }
+    return this._worker;
+  }
+
+  /**
+   * Kills the process.
+   *
+   * @param {integer} [timeout=300]
+   *        A timeout, in milliseconds, after which the process will be forcibly
+   *        killed. On platforms which support it, the process will be sent
+   *        a `SIGTERM` signal immediately, so that it has a chance to terminate
+   *        gracefully, and a `SIGKILL` signal if it hasn't exited within
+   *        `timeout` milliseconds. On other platforms (namely Windows), the
+   *        process will be forcibly terminated immediately.
+   *
+   * @returns {Promise<object>}
+   *          Resolves to an object with an `exitCode` property when the process
+   *          has exited.
+   */
+  kill(timeout = 300) {
+    // If the process has already exited, don't bother sending a signal.
+    if (this.exitCode != null) {
+      return this.wait();
+    }
+
+    let force = timeout <= 0;
+    this.worker.call("kill", [this.id, force]);
+
+    if (!force) {
+      setTimeout(() => {
+        if (this.exitCode == null) {
+          this.worker.call("kill", [this.id, true]);
+        }
+      }, timeout);
+    }
+
+    return this.wait();
+  }
+
+  /**
+   * Returns a promise which resolves to the process's exit code, once it has
+   * exited.
+   *
+   * @returns {Promise<object>}
+   * Resolves to an object with an `exitCode` property, containing the
+   * process's exit code, once the process has exited.
+   *
+   * On Unix-like systems, a negative exit code indicates that the
+   * process was killed by a signal whose signal number is the absolute
+   * value of the error code. On Windows, an exit code of -9 indicates
+   * that the process was killed via the {@linkcode BaseProcess#kill kill()}
+   * method.
+   */
+  wait() {
+    return this.exitPromise;
+  }
+}