1 files changed, 203 insertions, 0 deletions
diff --git a/toolkit/modules/subprocess/subprocess_unix.sys.mjs b/toolkit/modules/subprocess/subprocess_unix.sys.mjs
new file mode 100644
index 0000000000..59b5873af2
--- /dev/null
+++ b/toolkit/modules/subprocess/subprocess_unix.sys.mjs
@@ -0,0 +1,203 @@
+/* -*- 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/. */
+
+import {
+  BaseProcess,
+  PromiseWorker,
+} from "resource://gre/modules/subprocess/subprocess_common.sys.mjs";
+
+import { ctypes } from "resource://gre/modules/ctypes.sys.mjs";
+
+var obj = { ctypes };
+Services.scriptloader.loadSubScript(
+  "resource://gre/modules/subprocess/subprocess_shared.js",
+  obj
+);
+Services.scriptloader.loadSubScript(
+  "resource://gre/modules/subprocess/subprocess_shared_unix.js",
+  obj
+);
+
+const { SubprocessConstants, LIBC } = obj;
+
+// libc is exported for tests.
+export var libc = obj.libc;
+
+class UnixPromiseWorker extends PromiseWorker {
+  constructor(...args) {
+    super(...args);
+
+    let fds = ctypes.int.array(2)();
+    let res = libc.pipe(fds);
+    if (res == -1) {
+      throw new Error("Unable to create pipe");
+    }
+
+    this.signalFd = fds[1];
+
+    libc.fcntl(fds[0], LIBC.F_SETFL, LIBC.O_NONBLOCK);
+    libc.fcntl(fds[0], LIBC.F_SETFD, LIBC.FD_CLOEXEC);
+    libc.fcntl(fds[1], LIBC.F_SETFD, LIBC.FD_CLOEXEC);
+
+    this.call("init", [{ signalFd: fds[0] }]);
+  }
+
+  closePipe() {
+    if (this.signalFd) {
+      libc.close(this.signalFd);
+      this.signalFd = null;
+    }
+  }
+
+  onClose() {
+    this.closePipe();
+    super.onClose();
+  }
+
+  signalWorker() {
+    libc.write(this.signalFd, new ArrayBuffer(1), 1);
+  }
+
+  postMessage(...args) {
+    this.signalWorker();
+    return super.postMessage(...args);
+  }
+}
+
+class Process extends BaseProcess {
+  static get WORKER_URL() {
+    return "resource://gre/modules/subprocess/subprocess_unix.worker.js";
+  }
+
+  static get WorkerClass() {
+    return UnixPromiseWorker;
+  }
+}
+
+// Convert a null-terminated char pointer into a sized char array, and then
+// convert that into a JS typed array.
+// The resulting array will not be null-terminated.
+function ptrToUint8Array(input) {
+  let { cast, uint8_t } = ctypes;
+
+  let len = 0;
+  for (
+    let ptr = cast(input, uint8_t.ptr);
+    ptr.contents;
+    ptr = ptr.increment()
+  ) {
+    len++;
+  }
+
+  let aryPtr = cast(input, uint8_t.array(len).ptr);
+  return new Uint8Array(aryPtr.contents);
+}
+
+var SubprocessUnix = {
+  Process,
+
+  call(options) {
+    return Process.create(options);
+  },
+
+  *getEnvironment() {
+    let environ;
+    if (Services.appinfo.OS === "Darwin") {
+      environ = libc._NSGetEnviron().contents;
+    } else {
+      environ = libc.environ;
+    }
+
+    const EQUAL = "=".charCodeAt(0);
+    let decoder = new TextDecoder("utf-8", { fatal: true });
+
+    function decode(array) {
+      try {
+        return decoder.decode(array);
+      } catch (e) {
+        return array;
+      }
+    }
+
+    for (
+      let envp = environ;
+      !envp.isNull() && !envp.contents.isNull();
+      envp = envp.increment()
+    ) {
+      let buf = ptrToUint8Array(envp.contents);
+
+      for (let i = 0; i < buf.length; i++) {
+        if (buf[i] == EQUAL) {
+          yield [decode(buf.subarray(0, i)), decode(buf.subarray(i + 1))];
+          break;
+        }
+      }
+    }
+  },
+
+  isExecutableFile: async function isExecutable(path) {
+    if (!PathUtils.isAbsolute(path)) {
+      return false;
+    }
+
+    try {
+      let info = await IOUtils.stat(path);
+
+      // FIXME: We really want access(path, X_OK) here, but IOUtils does not
+      // support it.
+      return info.type !== "directory" && info.permissions & 0o111;
+    } catch (e) {
+      return false;
+    }
+  },
+
+  /**
+   * Searches for the given executable file in the system executable
+   * file paths as specified by the PATH environment variable.
+   *
+   * On Windows, if the unadorned filename cannot be found, the
+   * extensions in the semicolon-separated list in the PATHEXT
+   * environment variable are successively appended to the original
+   * name and searched for in turn.
+   *
+   * @param {string} bin
+   *        The name of the executable to find.
+   * @param {object} environment
+   *        An object containing a key for each environment variable to be used
+   *        in the search.
+   * @returns {Promise<string>}
+   */
+  async pathSearch(bin, environment) {
+    if (PathUtils.isAbsolute(bin)) {
+      if (await this.isExecutableFile(bin)) {
+        return bin;
+      }
+      let error = new Error(
+        `File at path "${bin}" does not exist, or is not executable`
+      );
+      error.errorCode = SubprocessConstants.ERROR_BAD_EXECUTABLE;
+      throw error;
+    }
+
+    let dirs = [];
+    if (typeof environment.PATH === "string") {
+      dirs = environment.PATH.split(":");
+    }
+
+    for (let dir of dirs) {
+      let path = PathUtils.join(dir, bin);
+
+      if (await this.isExecutableFile(path)) {
+        return path;
+      }
+    }
+    let error = new Error(`Executable not found: ${bin}`);
+    error.errorCode = SubprocessConstants.ERROR_BAD_EXECUTABLE;
+    throw error;
+  },
+};
+
+export var SubprocessImpl = SubprocessUnix;