From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- .../shared/heapsnapshot/HeapSnapshotFileUtils.js | 85 ++++++++++++++++++++++ 1 file changed, 85 insertions(+) create mode 100644 devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js (limited to 'devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js') diff --git a/devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js b/devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js new file mode 100644 index 0000000000..ab804eded1 --- /dev/null +++ b/devtools/shared/heapsnapshot/HeapSnapshotFileUtils.js @@ -0,0 +1,85 @@ +/* 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/. */ + +// Heap snapshots are always saved in the temp directory, and have a regular +// naming convention. This module provides helpers for working with heap +// snapshot files in a safe manner. Because we attempt to avoid unnecessary +// copies of the heap snapshot files by checking the local filesystem for a heap +// snapshot file with the given snapshot id, we want to ensure that we are only +// attempting to open heap snapshot files and not `~/.ssh/id_rsa`, for +// example. Therefore, the RDP only talks about snapshot ids, or transfering the +// bulk file data. A file path can be recovered from a snapshot id, which allows +// one to check for the presence of the heap snapshot file on the local file +// system, but we don't have to worry about opening arbitrary files. +// +// The heap snapshot file path conventions permits the following forms: +// +// $TEMP_DIRECTORY/XXXXXXXXXX.fxsnapshot +// $TEMP_DIRECTORY/XXXXXXXXXX-XXXXX.fxsnapshot +// +// Where the strings of "X" are zero or more digits. + +"use strict"; + +const lazy = {}; +ChromeUtils.defineESModuleGetters(lazy, { + FileUtils: "resource://gre/modules/FileUtils.sys.mjs", +}); + +function getHeapSnapshotFileTemplate() { + return PathUtils.join(PathUtils.tempDir, `${Date.now()}.fxsnapshot`); +} + +/** + * Get a unique temp file path for a new heap snapshot. The file is guaranteed + * not to exist before this call. + * + * @returns String + */ +exports.getNewUniqueHeapSnapshotTempFilePath = function () { + const file = new lazy.FileUtils.File(getHeapSnapshotFileTemplate()); + // The call to createUnique will append "-N" after the leaf name (but before + // the extension) until a new file is found and create it. This guarantees we + // won't accidentally choose the same file twice. + file.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, 0o666); + return file.path; +}; + +function isValidSnapshotFileId(snapshotId) { + return /^\d+(\-\d+)?$/.test(snapshotId); +} + +/** + * Get the file path for the given snapshot id. + * + * @param {String} snapshotId + * + * @returns String | null + */ +exports.getHeapSnapshotTempFilePath = function (snapshotId) { + // Don't want anyone sneaking "../../../.." strings into the snapshot id and + // trying to make us open arbitrary files. + if (!isValidSnapshotFileId(snapshotId)) { + return null; + } + return PathUtils.join(PathUtils.tempDir, snapshotId + ".fxsnapshot"); +}; + +/** + * Return true if we have the heap snapshot file for the given snapshot id on + * the local file system. False is returned otherwise. + * + * @returns Promise + */ +exports.haveHeapSnapshotTempFile = function (snapshotId) { + const path = exports.getHeapSnapshotTempFilePath(snapshotId); + if (!path) { + return Promise.resolve(false); + } + + return IOUtils.stat(path).then( + () => true, + () => false + ); +}; -- cgit v1.2.3