Bug 1269501: Part 3 - Add new Subprocess IPC module. r=aswan r=mhowell rs=bsmedberg

MozReview-Commit-ID: 6vl5xBTBXiF

toolkit/modules/subprocess/subprocess_win.jsm

@@ -0,0 +1,138 @@
+/* -*- 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 */
+
+/* exported SubprocessImpl */
+
+/* globals BaseProcess */
+
+var {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
+
+var EXPORTED_SYMBOLS = ["SubprocessImpl"];
+
+Cu.import("resource://gre/modules/ctypes.jsm");
+Cu.import("resource://gre/modules/osfile.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+Cu.import("resource://gre/modules/subprocess/subprocess_common.jsm");
+
+Services.scriptloader.loadSubScript("resource://gre/modules/subprocess/subprocess_shared.js", this);
+Services.scriptloader.loadSubScript("resource://gre/modules/subprocess/subprocess_shared_win.js", this);
+
+class Process extends BaseProcess {
+  static get WORKER_URL() {
+    return "resource://gre/modules/subprocess/subprocess_worker_win.js";
+  }
+}
+
+var SubprocessWin = {
+  Process,
+
+  call(options) {
+    return Process.create(options);
+  },
+
+
+  * getEnvironment() {
+    let env = libc.GetEnvironmentStringsW();
+    try {
+      for (let p = env, q = env; ; p = p.increment()) {
+        if (p.contents == "\0") {
+          if (String(p) == String(q)) {
+            break;
+          }
+
+          let str = q.readString();
+          q = p.increment();
+
+          let idx = str.indexOf("=");
+          if (idx == 0) {
+            idx = str.indexOf("=", 1);
+          }
+
+          if (idx >= 0) {
+            yield [str.slice(0, idx), str.slice(idx + 1)];
+          }
+        }
+      }
+    } finally {
+      libc.FreeEnvironmentStringsW(env);
+    }
+  },
+
+  isExecutableFile: Task.async(function* (path) {
+    if (!OS.Path.split(path).absolute) {
+      return false;
+    }
+
+    try {
+      let info = yield OS.File.stat(path);
+      return !(info.isDir || info.isSymlink);
+    } 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>}
+   */
+  pathSearch: Task.async(function* (bin, environment) {
+    let split = OS.Path.split(bin);
+    if (split.absolute) {
+      if (yield this.isExecutableFile(bin)) {
+        return bin;
+      }
+      let error = new Error(`File at path "${bin}" does not exist, or is not a normal file`);
+      error.errorCode = SubprocessConstants.ERROR_BAD_EXECUTABLE;
+      throw error;
+    }
+
+    let dirs = [];
+    let exts = [];
+    if (environment.PATH) {
+      dirs = environment.PATH.split(";");
+    }
+    if (environment.PATHEXT) {
+      exts = environment.PATHEXT.split(";");
+    }
+
+    for (let dir of dirs) {
+      let path = OS.Path.join(dir, bin);
+
+      if (yield this.isExecutableFile(path)) {
+        return path;
+      }
+
+      for (let ext of exts) {
+        let file = path + ext;
+
+        if (yield this.isExecutableFile(file)) {
+          return file;
+        }
+      }
+    }
+    let error = new Error(`Executable not found: ${bin}`);
+    error.errorCode = SubprocessConstants.ERROR_BAD_EXECUTABLE;
+    throw error;
+  }),
+};
+
+var SubprocessImpl = SubprocessWin;