gecko/devtools/server/actors/heap-snapshot-file.js
Nick Fitzgerald 0603f55db4 Bug 1207645 - Create HeapSnapshotFileActor; r=jryans
This commit creates the HeapSnapshotFileActor and moves the transferHeapSnapshot
method from MemoryActor to HeapSnapshotFileActor. This is necessary because
child processes in e10s are sandboxed and do not have access to the file system,
and because MemoryActor is in the sandboxed child process it cannot open the
file and send it over the RDP.

This complexity is hidden at the MemoryFront layer. Users of MemoryFront will
still simply call its saveHeapSnapshot method, and do not need to worry about
the inner workings of how heap snapshot files are transferred over the RDP. This
required adding a third parameter to MemoryFront's initialize method: the
listTabs response.
2015-09-25 15:35:02 -07:00

75 lines
2.4 KiB
JavaScript

/* 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";
const protocol = require("devtools/server/protocol");
const { method, Arg } = protocol;
const Services = require("Services");
loader.lazyRequireGetter(this, "DevToolsUtils",
"devtools/shared/DevToolsUtils");
loader.lazyRequireGetter(this, "OS", "resource://gre/modules/osfile.jsm", true);
loader.lazyRequireGetter(this, "Task", "resource://gre/modules/Task.jsm", true);
loader.lazyRequireGetter(this, "HeapSnapshotFileUtils",
"devtools/shared/heapsnapshot/HeapSnapshotFileUtils");
/**
* The HeapSnapshotFileActor handles transferring heap snapshot files from the
* server to the client. This has to be a global actor in the parent process
* because child processes are sandboxed and do not have access to the file
* system.
*/
exports.HeapSnapshotFileActor = protocol.ActorClass({
typeName: "heapSnapshotFile",
initialize: function (conn, parent) {
if (Services.appInfo &&
(Services.appInfo.processType !==
Services.appInfo.PROCESS_TYPE_DEFAULT)) {
const err = new Error("Attempt to create a HeapSnapshotFileActor in a " +
"child process! The HeapSnapshotFileActor *MUST* " +
"be in the parent process!");
DevToolsUtils.reportException(
"HeapSnapshotFileActor.prototype.initialize", err);
return;
}
protocol.Actor.prototype.initialize.call(this, conn, parent);
},
/**
* @see MemoryFront.prototype.transferHeapSnapshot
*/
transferHeapSnapshot: method(Task.async(function* (snapshotId) {
const snapshotFilePath =
HeapSnapshotFileUtils.getHeapSnapshotTempFilePath(snapshotId);
if (!snapshotFilePath) {
throw new Error(`No heap snapshot with id: ${snapshotId}`);
}
const streamPromise = DevToolsUtils.openFileStream(snapshotFilePath);
const { size } = yield OS.File.stat(snapshotFilePath);
const bulkPromise = this.conn.startBulkSend({
actor: this.actorID,
type: "heap-snapshot",
length: size
});
const [bulk, stream] = yield Promise.all([bulkPromise, streamPromise]);
try {
yield bulk.copyFrom(stream);
} finally {
stream.close();
}
}), {
request: {
snapshotId: Arg(0, "string")
}
}),
});