1
0
Fork 0
firefox/devtools/server/actors/heap-snapshot-file.js
Daniel Baumann 5e9a113729
Adding upstream version 140.0.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
2025-06-25 09:37:52 +02:00

76 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 { Actor } = require("resource://devtools/shared/protocol.js");
const {
heapSnapshotFileSpec,
} = require("resource://devtools/shared/specs/heap-snapshot-file.js");
loader.lazyRequireGetter(
this,
"DevToolsUtils",
"resource://devtools/shared/DevToolsUtils.js"
);
loader.lazyRequireGetter(
this,
"HeapSnapshotFileUtils",
"resource://devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js"
);
/**
* 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
*
* @param {String} snapshotId
* The ID returned by MemoryActor's saveHeapSnapshot method.
* @param {Function} startBulkSend
* Function provided by protocol.js Actor framework to initiate
* the bulk reply. This methods returns a promise resolving to
* a StreamCopier instance, whose `copyFrom` method allows
* to send the data back to the client via an input stream.
*/
async transferHeapSnapshot(snapshotId, startBulkSend) {
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 = startBulkSend(size);
const [bulk, stream] = await Promise.all([bulkPromise, streamPromise]);
try {
await bulk.copyFrom(stream);
} finally {
stream.close();
}
}
};