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/* 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 { Actor } = require("resource://devtools/shared/protocol.js");
const {
heapSnapshotFileSpec,
loader.lazyRequireGetter(
this,
"DevToolsUtils",
);
loader.lazyRequireGetter(
this,
"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 = class HeapSnapshotFileActor extends Actor {
constructor(conn) {
super(conn, heapSnapshotFileSpec);
if (
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's constructor", err);
}
}
/**
* @see MemoryFront.prototype.transferHeapSnapshot
*/
async transferHeapSnapshot(snapshotId) {
const snapshotFilePath =
HeapSnapshotFileUtils.getHeapSnapshotTempFilePath(snapshotId);
if (!snapshotFilePath) {
throw new Error(`No heap snapshot with id: ${snapshotId}`);
}
const streamPromise = DevToolsUtils.openFileStream(snapshotFilePath);
const { size } = await IOUtils.stat(snapshotFilePath);
const bulkPromise = this.conn.startBulkSend({
actor: this.actorID,
type: "heap-snapshot",
length: size,
});
const [bulk, stream] = await Promise.all([bulkPromise, streamPromise]);
try {
await bulk.copyFrom(stream);
} finally {
stream.close();
}
}
};