Bug 1608276 - Part 1: Do not use global this when loading subprocess scripts. r=mossop

Differential Revision: https://phabricator.services.mozilla.com/D144700

toolkit/modules/subprocess/subprocess_common.jsm

@@ -20,12 +20,14 @@ ChromeUtils.defineModuleGetter(
   "resource://gre/modules/Timer.jsm"
 );
 
+var obj = {};
 Services.scriptloader.loadSubScript(
   "resource://gre/modules/subprocess/subprocess_shared.js",
-  this
+  obj
 );
 
-/* global SubprocessConstants */
+const { SubprocessConstants, ArrayBuffer_transfer } = obj;
+
 var EXPORTED_SYMBOLS = ["BaseProcess", "PromiseWorker", "SubprocessConstants"];
 
 const BUFFER_SIZE = 32768;
@@ -396,9 +398,9 @@ class InputPipe extends Pipe {
         let buffer = this.buffers[0];
 
         this.buffers[0] = buffer.slice(length);
-        result = ArrayBuffer.transfer(buffer, length);
+        result = ArrayBuffer_transfer(buffer, length);
       } else {
-        result = ArrayBuffer.transfer(this.buffers.shift(), length);
+        result = ArrayBuffer_transfer(this.buffers.shift(), length);
         let u8result = new Uint8Array(result);
 
         while (byteLength < length) {

toolkit/modules/subprocess/subprocess_shared.js

@@ -5,29 +5,28 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
-/* exported Library, SubprocessConstants */
+/* exported ArrayBuffer_transfer, Library, SubprocessConstants */
 
-if (!ArrayBuffer.transfer) {
-  /**
-   * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer/transfer
-   *
-   * @param {ArrayBuffer} buffer
-   * @param {integer} [size = buffer.byteLength]
-   * @returns {ArrayBuffer}
-   */
-  ArrayBuffer.transfer = function(buffer, size = buffer.byteLength) {
-    let u8out = new Uint8Array(size);
-    let u8buffer = new Uint8Array(buffer, 0, Math.min(size, buffer.byteLength));
-
-    u8out.set(u8buffer);
-
-    return u8out.buffer;
-  };
-}
+/**
+ * Returns a new ArrayBuffer whose contents have been taken from the `buffer`'s
+ * data and then is either truncated or zero-extended by `size`. If `size` is
+ * undefined, the `byteLength` of the `buffer` is used. This operation leaves
+ * `buffer` in a detached state.
+ *
+ * @param {ArrayBuffer} buffer
+ * @param {integer} [size = buffer.byteLength]
+ * @returns {ArrayBuffer}
+ */
+var ArrayBuffer_transfer = function(buffer, size = buffer.byteLength) {
+  let u8out = new Uint8Array(size);
+  let u8buffer = new Uint8Array(buffer, 0, Math.min(size, buffer.byteLength));
+  u8out.set(u8buffer);
+  return u8out.buffer;
+};
 
 var libraries = {};
 
-class Library {
+var Library = class Library {
   constructor(name, names, definitions) {
     if (name in libraries) {
       return libraries[name];
@@ -66,14 +65,14 @@ class Library {
       },
     });
   }
-}
+};
 
 /**
  * Holds constants which apply to various Subprocess operations.
  * @namespace
  * @lends Subprocess
  */
-const SubprocessConstants = {
+var SubprocessConstants = {
   /**
    * @property {integer} ERROR_END_OF_FILE
    *           The operation failed because the end of the file was reached.

toolkit/modules/subprocess/subprocess_shared_unix.js

@@ -5,12 +5,13 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
-/* exported libc */
+/* exported LIBC, libc */
 
 // This file is loaded into the same scope as subprocess_unix.jsm
+/* import-globals-from subprocess_shared.js */
 /* import-globals-from subprocess_unix.jsm */
 
-const LIBC = OS.Constants.libc;
+var LIBC = OS.Constants.libc;
 
 const LIBC_CHOICES = ["libc.so", "libSystem.B.dylib", "a.out"];
 

toolkit/modules/subprocess/subprocess_shared_win.js

@@ -5,9 +5,10 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
-/* exported LIBC, Win, createPipe, libc */
+/* exported LIBC, Win, createPipe, libc, win32 */
 
 // This file is loaded into the same scope as subprocess_win.jsm
+/* import-globals-from subprocess_shared.js */
 /* import-globals-from subprocess_win.jsm */
 
 const LIBC = OS.Constants.libc;

toolkit/modules/subprocess/subprocess_unix.jsm

@@ -18,17 +18,18 @@ const { BaseProcess, PromiseWorker } = ChromeUtils.import(
   "resource://gre/modules/subprocess/subprocess_common.jsm"
 );
 
-/* import-globals-from subprocess_shared.js */
-/* import-globals-from subprocess_shared_unix.js */
+var obj = {};
 Services.scriptloader.loadSubScript(
   "resource://gre/modules/subprocess/subprocess_shared.js",
-  this
+  obj
 );
 Services.scriptloader.loadSubScript(
   "resource://gre/modules/subprocess/subprocess_shared_unix.js",
-  this
+  obj
 );
 
+const { SubprocessConstants, libc, LIBC } = obj;
+
 class UnixPromiseWorker extends PromiseWorker {
   constructor(...args) {
     super(...args);

toolkit/modules/subprocess/subprocess_win.jsm

@@ -31,17 +31,18 @@ XPCOMUtils.defineLazyServiceGetter(
   "nsIEnvironment"
 );
 
-/* import-globals-from subprocess_shared.js */
-/* import-globals-from subprocess_shared_win.js */
+var obj = {};
 Services.scriptloader.loadSubScript(
   "resource://gre/modules/subprocess/subprocess_shared.js",
-  this
+  obj
 );
 Services.scriptloader.loadSubScript(
   "resource://gre/modules/subprocess/subprocess_shared_win.js",
-  this
+  obj
 );
 
+const { SubprocessConstants, libc, win32 } = obj;
+
 class WinPromiseWorker extends PromiseWorker {
   constructor(...args) {
     super(...args);

toolkit/modules/subprocess/subprocess_worker_unix.js

@@ -137,7 +137,7 @@ class InputPipe extends Pipe {
     }
 
     if (read < buffer.byteLength) {
-      return ArrayBuffer.transfer(buffer, read);
+      return ArrayBuffer_transfer(buffer, read);
     }
 
     return buffer;

toolkit/modules/subprocess/subprocess_worker_win.js

@@ -224,7 +224,7 @@ class InputPipe extends Pipe {
       if (read == buffer.byteLength) {
         resolve(buffer);
       } else {
-        resolve(ArrayBuffer.transfer(buffer, read));
+        resolve(ArrayBuffer_transfer(buffer, read));
       }
 
       if (this.pending.length) {