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September 15, 2019 00:43
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resource://gre/modules/osfile/osfile_async_front.jsm
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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/. */ | |
/** | |
* Asynchronous front-end for OS.File. | |
* | |
* This front-end is meant to be imported from the main thread. In turn, | |
* it spawns one worker (perhaps more in the future) and delegates all | |
* disk I/O to this worker. | |
* | |
* Documentation note: most of the functions and methods in this module | |
* return promises. For clarity, we denote as follows a promise that may resolve | |
* with type |A| and some value |value| or reject with type |B| and some | |
* reason |reason| | |
* @resolves {A} value | |
* @rejects {B} reason | |
*/ | |
"use strict"; | |
var EXPORTED_SYMBOLS = ["OS"]; | |
var SharedAll = {}; | |
ChromeUtils.import( | |
"resource://gre/modules/osfile/osfile_shared_allthreads.jsm", | |
SharedAll | |
); | |
ChromeUtils.import("resource://gre/modules/Timer.jsm", this); | |
// Boilerplate, to simplify the transition to require() | |
var LOG = SharedAll.LOG.bind(SharedAll, "Controller"); | |
var isTypedArray = SharedAll.isTypedArray; | |
// The constructor for file errors. | |
var SysAll = {}; | |
if (SharedAll.Constants.Win) { | |
ChromeUtils.import( | |
"resource://gre/modules/osfile/osfile_win_allthreads.jsm", | |
SysAll | |
); | |
} else if (SharedAll.Constants.libc) { | |
ChromeUtils.import( | |
"resource://gre/modules/osfile/osfile_unix_allthreads.jsm", | |
SysAll | |
); | |
} else { | |
throw new Error("I am neither under Windows nor under a Posix system"); | |
} | |
var OSError = SysAll.Error; | |
var Type = SysAll.Type; | |
var Path = {}; | |
ChromeUtils.import("resource://gre/modules/osfile/ospath.jsm", Path); | |
// The library of promises. | |
ChromeUtils.defineModuleGetter( | |
this, | |
"PromiseUtils", | |
"resource://gre/modules/PromiseUtils.jsm" | |
); | |
// The implementation of communications | |
ChromeUtils.import("resource://gre/modules/PromiseWorker.jsm", this); | |
ChromeUtils.import("resource://gre/modules/Services.jsm", this); | |
ChromeUtils.import("resource://gre/modules/AsyncShutdown.jsm", this); | |
var Native = ChromeUtils.import( | |
"resource://gre/modules/osfile/osfile_native.jsm", | |
null | |
); | |
// It's possible for osfile.jsm to get imported before the profile is | |
// set up. In this case, some path constants aren't yet available. | |
// Here, we make them lazy loaders. | |
function lazyPathGetter(constProp, dirKey) { | |
return function() { | |
let path; | |
try { | |
path = Services.dirsvc.get(dirKey, Ci.nsIFile).path; | |
delete SharedAll.Constants.Path[constProp]; | |
SharedAll.Constants.Path[constProp] = path; | |
} catch (ex) { | |
// Ignore errors if the value still isn't available. Hopefully | |
// the next access will return it. | |
} | |
return path; | |
}; | |
} | |
for (let [constProp, dirKey] of [ | |
["localProfileDir", "ProfLD"], | |
["profileDir", "ProfD"], | |
["userApplicationDataDir", "UAppData"], | |
["winAppDataDir", "AppData"], | |
["winLocalAppDataDir", "LocalAppData"], | |
["winStartMenuProgsDir", "Progs"], | |
["tmpDir", "TmpD"], | |
["homeDir", "Home"], | |
["macUserLibDir", "ULibDir"], | |
]) { | |
if (constProp in SharedAll.Constants.Path) { | |
continue; | |
} | |
LOG( | |
"Installing lazy getter for OS.Constants.Path." + | |
constProp + | |
" because it isn't defined and profile may not be loaded." | |
); | |
Object.defineProperty(SharedAll.Constants.Path, constProp, { | |
get: lazyPathGetter(constProp, dirKey), | |
}); | |
} | |
/** | |
* Return a shallow clone of the enumerable properties of an object. | |
*/ | |
var clone = SharedAll.clone; | |
/** | |
* Extract a shortened version of an object, fit for logging. | |
* | |
* This function returns a copy of the original object in which all | |
* long strings, Arrays, TypedArrays, ArrayBuffers are removed and | |
* replaced with placeholders. Use this function to sanitize objects | |
* if you wish to log them or to keep them in memory. | |
* | |
* @param {*} obj The obj to shorten. | |
* @return {*} array A shorter object, fit for logging. | |
*/ | |
function summarizeObject(obj) { | |
if (!obj) { | |
return null; | |
} | |
if (typeof obj == "string") { | |
if (obj.length > 1024) { | |
return { "Long string": obj.length }; | |
} | |
return obj; | |
} | |
if (typeof obj == "object") { | |
if (Array.isArray(obj)) { | |
if (obj.length > 32) { | |
return { "Long array": obj.length }; | |
} | |
return obj.map(summarizeObject); | |
} | |
if ("byteLength" in obj) { | |
// Assume TypedArray or ArrayBuffer | |
return { "Binary Data": obj.byteLength }; | |
} | |
let result = {}; | |
for (let k of Object.keys(obj)) { | |
result[k] = summarizeObject(obj[k]); | |
} | |
return result; | |
} | |
return obj; | |
} | |
// In order to expose Scheduler to the unfiltered Cu.import return value variant | |
// on B2G we need to save it to `this`. This does not make it public; | |
// EXPORTED_SYMBOLS still controls that in all cases. | |
var Scheduler = (this.Scheduler = { | |
/** | |
* |true| once we have sent at least one message to the worker. | |
* This field is unaffected by resetting the worker. | |
*/ | |
launched: false, | |
/** | |
* |true| once shutdown has begun i.e. we should reject any | |
* message, including resets. | |
*/ | |
shutdown: false, | |
/** | |
* A promise resolved once all currently pending operations are complete. | |
* | |
* This promise is never rejected and the result is always undefined. | |
*/ | |
queue: Promise.resolve(), | |
/** | |
* A promise resolved once all currently pending `kill` operations | |
* are complete. | |
* | |
* This promise is never rejected and the result is always undefined. | |
*/ | |
_killQueue: Promise.resolve(), | |
/** | |
* Miscellaneous debugging information | |
*/ | |
Debugging: { | |
/** | |
* The latest message sent and still waiting for a reply. | |
*/ | |
latestSent: undefined, | |
/** | |
* The latest reply received, or null if we are waiting for a reply. | |
*/ | |
latestReceived: undefined, | |
/** | |
* Number of messages sent to the worker. This includes the | |
* initial SET_DEBUG, if applicable. | |
*/ | |
messagesSent: 0, | |
/** | |
* Total number of messages ever queued, including the messages | |
* sent. | |
*/ | |
messagesQueued: 0, | |
/** | |
* Number of messages received from the worker. | |
*/ | |
messagesReceived: 0, | |
}, | |
/** | |
* A timer used to automatically shut down the worker after some time. | |
*/ | |
resetTimer: null, | |
/** | |
* A flag indicating whether we had some activities when waiting the | |
* timer and if it's not we can shut down the worker. | |
*/ | |
hasRecentActivity: false, | |
/** | |
* The worker to which to send requests. | |
* | |
* If the worker has never been created or has been reset, this is a | |
* fresh worker, initialized with osfile_async_worker.js. | |
* | |
* @type {PromiseWorker} | |
*/ | |
get worker() { | |
if (!this._worker) { | |
// Either the worker has never been created or it has been | |
// reset. In either case, it is time to instantiate the worker. | |
this._worker = new BasePromiseWorker( | |
"resource://gre/modules/osfile/osfile_async_worker.js" | |
); | |
this._worker.log = LOG; | |
this._worker.ExceptionHandlers["OS.File.Error"] = OSError.fromMsg; | |
let delay = Services.prefs.getIntPref("osfile.reset_worker_delay", 0); | |
if (delay) { | |
this.resetTimer = setInterval(() => { | |
if (this.hasRecentActivity) { | |
this.hasRecentActivity = false; | |
return; | |
} | |
clearInterval(this.resetTimer); | |
Scheduler.kill({ reset: true, shutdown: false }); | |
}, delay); | |
} | |
} | |
return this._worker; | |
}, | |
_worker: null, | |
/** | |
* Restart the OS.File worker killer timer. | |
*/ | |
restartTimer(arg) { | |
this.hasRecentActivity = true; | |
}, | |
/** | |
* Shutdown OS.File. | |
* | |
* @param {*} options | |
* - {boolean} shutdown If |true|, reject any further request. Otherwise, | |
* further requests will resurrect the worker. | |
* - {boolean} reset If |true|, instruct the worker to shutdown if this | |
* would not cause leaks. Otherwise, assume that the worker will be shutdown | |
* through some other mean. | |
*/ | |
kill({ shutdown, reset }) { | |
// Grab the kill queue to make sure that we | |
// cannot be interrupted by another call to `kill`. | |
let killQueue = this._killQueue; | |
// Deactivate the queue, to ensure that no message is sent | |
// to an obsolete worker (we reactivate it in the `finally`). | |
// This needs to be done right now so that we maintain relative | |
// ordering with calls to post(), etc. | |
let deferred = PromiseUtils.defer(); | |
let savedQueue = this.queue; | |
this.queue = deferred.promise; | |
return (this._killQueue = (async () => { | |
await killQueue; | |
// From this point, and until the end of the Task, we are the | |
// only call to `kill`, regardless of any `yield`. | |
await savedQueue; | |
try { | |
// Enter critical section: no yield in this block | |
// (we want to make sure that we remain the only | |
// request in the queue). | |
if (!this.launched || this.shutdown || !this._worker) { | |
// Nothing to kill | |
this.shutdown = this.shutdown || shutdown; | |
this._worker = null; | |
return null; | |
} | |
// Exit critical section | |
let message = ["Meta_shutdown", [reset]]; | |
Scheduler.latestReceived = []; | |
let stack = new Error().stack; | |
Scheduler.latestSent = [Date.now(), stack, ...message]; | |
// Wait for result | |
let resources; | |
try { | |
resources = await this._worker.post(...message); | |
Scheduler.latestReceived = [Date.now(), message]; | |
} catch (ex) { | |
LOG("Could not dispatch Meta_reset", ex); | |
// It's most likely a programmer error, but we'll assume that | |
// the worker has been shutdown, as it's less risky than the | |
// opposite stance. | |
resources = { | |
openedFiles: [], | |
openedDirectoryIterators: [], | |
killed: true, | |
}; | |
Scheduler.latestReceived = [Date.now(), message, ex]; | |
} | |
let { openedFiles, openedDirectoryIterators, killed } = resources; | |
if ( | |
!reset && | |
((openedFiles && openedFiles.length) || | |
(openedDirectoryIterators && openedDirectoryIterators.length)) | |
) { | |
// The worker still holds resources. Report them. | |
let msg = ""; | |
if (openedFiles.length > 0) { | |
msg += | |
"The following files are still open:\n" + openedFiles.join("\n"); | |
} | |
if (openedDirectoryIterators.length > 0) { | |
msg += | |
"The following directory iterators are still open:\n" + | |
openedDirectoryIterators.join("\n"); | |
} | |
LOG("WARNING: File descriptors leaks detected.\n" + msg); | |
} | |
// Make sure that we do not leave an invalid |worker| around. | |
if (killed || shutdown) { | |
this._worker = null; | |
} | |
this.shutdown = shutdown; | |
return resources; | |
} finally { | |
// Resume accepting messages. If we have set |shutdown| to |true|, | |
// any pending/future request will be rejected. Otherwise, any | |
// pending/future request will spawn a new worker if necessary. | |
deferred.resolve(); | |
} | |
})()); | |
}, | |
/** | |
* Push a task at the end of the queue. | |
* | |
* @param {function} code A function returning a Promise. | |
* This function will be executed once all the previously | |
* pushed tasks have completed. | |
* @return {Promise} A promise with the same behavior as | |
* the promise returned by |code|. | |
*/ | |
push(code) { | |
let promise = this.queue.then(code); | |
// By definition, |this.queue| can never reject. | |
this.queue = promise.catch(() => undefined); | |
// Fork |promise| to ensure that uncaught errors are reported | |
return promise.then(); | |
}, | |
/** | |
* Post a message to the worker thread. | |
* | |
* @param {string} method The name of the method to call. | |
* @param {...} args The arguments to pass to the method. These arguments | |
* must be clonable. | |
* The last argument by convention may be an object `options`, with some of | |
* the following fields: | |
* - {number|null} outSerializationDuration A parameter to be filled with | |
* duration of the `this.worker.post` method. | |
* @return {Promise} A promise conveying the result/error caused by | |
* calling |method| with arguments |args|. | |
*/ | |
post: function post(method, args = undefined, closure = undefined) { | |
if (this.shutdown) { | |
LOG( | |
"OS.File is not available anymore. The following request has been rejected.", | |
method, | |
args | |
); | |
return Promise.reject( | |
new Error("OS.File has been shut down. Rejecting post to " + method) | |
); | |
} | |
let firstLaunch = !this.launched; | |
this.launched = true; | |
if (firstLaunch && SharedAll.Config.DEBUG) { | |
// If we have delayed sending SET_DEBUG, do it now. | |
this.worker.post("SET_DEBUG", [true]); | |
Scheduler.Debugging.messagesSent++; | |
} | |
Scheduler.Debugging.messagesQueued++; | |
return this.push(async () => { | |
if (this.shutdown) { | |
LOG( | |
"OS.File is not available anymore. The following request has been rejected.", | |
method, | |
args | |
); | |
throw new Error( | |
"OS.File has been shut down. Rejecting request to " + method | |
); | |
} | |
// Update debugging information. As |args| may be quite | |
// expensive, we only keep a shortened version of it. | |
Scheduler.Debugging.latestReceived = null; | |
Scheduler.Debugging.latestSent = [ | |
Date.now(), | |
method, | |
summarizeObject(args), | |
]; | |
// Don't kill the worker just yet | |
Scheduler.restartTimer(); | |
// The last object inside the args may be an options object. | |
let options = null; | |
if ( | |
args && | |
args.length >= 1 && | |
typeof args[args.length - 1] === "object" | |
) { | |
options = args[args.length - 1]; | |
} | |
let reply; | |
try { | |
try { | |
Scheduler.Debugging.messagesSent++; | |
Scheduler.Debugging.latestSent = Scheduler.Debugging.latestSent.slice( | |
0, | |
2 | |
); | |
let serializationStartTimeMs = Date.now(); | |
reply = await this.worker.post(method, args, closure); | |
let serializationEndTimeMs = Date.now(); | |
Scheduler.Debugging.latestReceived = [ | |
Date.now(), | |
summarizeObject(reply), | |
]; | |
// There were no options for recording the serialization duration. | |
if (options && "outSerializationDuration" in options) { | |
// The difference might be negative for very fast operations, since Date.now() may not be monotonic. | |
let serializationDurationMs = Math.max( | |
0, | |
serializationEndTimeMs - serializationStartTimeMs | |
); | |
if (typeof options.outSerializationDuration === "number") { | |
options.outSerializationDuration += serializationDurationMs; | |
} else { | |
options.outSerializationDuration = serializationDurationMs; | |
} | |
} | |
return reply; | |
} finally { | |
Scheduler.Debugging.messagesReceived++; | |
} | |
} catch (error) { | |
Scheduler.Debugging.latestReceived = [ | |
Date.now(), | |
error.message, | |
error.fileName, | |
error.lineNumber, | |
]; | |
throw error; | |
} finally { | |
if (firstLaunch) { | |
Scheduler._updateTelemetry(); | |
} | |
Scheduler.restartTimer(); | |
} | |
}); | |
}, | |
/** | |
* Post Telemetry statistics. | |
* | |
* This is only useful on first launch. | |
*/ | |
_updateTelemetry() { | |
let worker = this.worker; | |
let workerTimeStamps = worker.workerTimeStamps; | |
if (!workerTimeStamps) { | |
// If the first call to OS.File results in an uncaught errors, | |
// the timestamps are absent. As this case is a developer error, | |
// let's not waste time attempting to extract telemetry from it. | |
return; | |
} | |
let HISTOGRAM_LAUNCH = Services.telemetry.getHistogramById( | |
"OSFILE_WORKER_LAUNCH_MS" | |
); | |
HISTOGRAM_LAUNCH.add( | |
worker.workerTimeStamps.entered - worker.launchTimeStamp | |
); | |
let HISTOGRAM_READY = Services.telemetry.getHistogramById( | |
"OSFILE_WORKER_READY_MS" | |
); | |
HISTOGRAM_READY.add( | |
worker.workerTimeStamps.loaded - worker.launchTimeStamp | |
); | |
}, | |
}); | |
const PREF_OSFILE_LOG = "toolkit.osfile.log"; | |
const PREF_OSFILE_LOG_REDIRECT = "toolkit.osfile.log.redirect"; | |
/** | |
* Safely read a PREF_OSFILE_LOG preference. | |
* Returns a value read or, in case of an error, oldPref or false. | |
* | |
* @param bool oldPref | |
* An optional value that the DEBUG flag was set to previously. | |
*/ | |
function readDebugPref(prefName, oldPref = false) { | |
// If neither pref nor oldPref were set, default it to false. | |
return Services.prefs.getBoolPref(prefName, oldPref); | |
} | |
/** | |
* Listen to PREF_OSFILE_LOG changes and update gShouldLog flag | |
* appropriately. | |
*/ | |
Services.prefs.addObserver(PREF_OSFILE_LOG, function prefObserver( | |
aSubject, | |
aTopic, | |
aData | |
) { | |
SharedAll.Config.DEBUG = readDebugPref( | |
PREF_OSFILE_LOG, | |
SharedAll.Config.DEBUG | |
); | |
if (Scheduler.launched) { | |
// Don't start the worker just to set this preference. | |
Scheduler.post("SET_DEBUG", [SharedAll.Config.DEBUG]); | |
} | |
}); | |
SharedAll.Config.DEBUG = readDebugPref(PREF_OSFILE_LOG, false); | |
Services.prefs.addObserver(PREF_OSFILE_LOG_REDIRECT, function prefObserver( | |
aSubject, | |
aTopic, | |
aData | |
) { | |
SharedAll.Config.TEST = readDebugPref( | |
PREF_OSFILE_LOG_REDIRECT, | |
OS.Shared.TEST | |
); | |
}); | |
SharedAll.Config.TEST = readDebugPref(PREF_OSFILE_LOG_REDIRECT, false); | |
/** | |
* If |true|, use the native implementaiton of OS.File methods | |
* whenever possible. Otherwise, force the use of the JS version. | |
*/ | |
var nativeWheneverAvailable = true; | |
const PREF_OSFILE_NATIVE = "toolkit.osfile.native"; | |
Services.prefs.addObserver(PREF_OSFILE_NATIVE, function prefObserver( | |
aSubject, | |
aTopic, | |
aData | |
) { | |
nativeWheneverAvailable = readDebugPref( | |
PREF_OSFILE_NATIVE, | |
nativeWheneverAvailable | |
); | |
}); | |
// Update worker's DEBUG flag if it's true. | |
// Don't start the worker just for this, though. | |
if (SharedAll.Config.DEBUG && Scheduler.launched) { | |
Scheduler.post("SET_DEBUG", [true]); | |
} | |
// Preference used to configure test shutdown observer. | |
const PREF_OSFILE_TEST_SHUTDOWN_OBSERVER = | |
"toolkit.osfile.test.shutdown.observer"; | |
AsyncShutdown.webWorkersShutdown.addBlocker( | |
"OS.File: flush pending requests, warn about unclosed files, shut down service.", | |
async function() { | |
// Give clients a last chance to enqueue requests. | |
await Barriers.shutdown.wait({ crashAfterMS: null }); | |
// Wait until all requests are complete and kill the worker. | |
await Scheduler.kill({ reset: false, shutdown: true }); | |
}, | |
() => { | |
let details = Barriers.getDetails(); | |
details.clients = Barriers.shutdown.state; | |
return details; | |
} | |
); | |
// Attaching an observer for PREF_OSFILE_TEST_SHUTDOWN_OBSERVER to enable or | |
// disable the test shutdown event observer. | |
// Note: By default the PREF_OSFILE_TEST_SHUTDOWN_OBSERVER is unset. | |
// Note: This is meant to be used for testing purposes only. | |
Services.prefs.addObserver( | |
PREF_OSFILE_TEST_SHUTDOWN_OBSERVER, | |
function prefObserver() { | |
// The temporary phase topic used to trigger the unclosed | |
// phase warning. | |
let TOPIC = Services.prefs.getCharPref( | |
PREF_OSFILE_TEST_SHUTDOWN_OBSERVER, | |
"" | |
); | |
if (TOPIC) { | |
// Generate a phase, add a blocker. | |
// Note that this can work only if AsyncShutdown itself has been | |
// configured for testing by the testsuite. | |
let phase = AsyncShutdown._getPhase(TOPIC); | |
phase.addBlocker( | |
"(for testing purposes) OS.File: warn about unclosed files", | |
() => Scheduler.kill({ shutdown: false, reset: false }) | |
); | |
} | |
} | |
); | |
/** | |
* Representation of a file, with asynchronous methods. | |
* | |
* @param {*} fdmsg The _message_ representing the platform-specific file | |
* handle. | |
* | |
* @constructor | |
*/ | |
var File = function File(fdmsg) { | |
// FIXME: At the moment, |File| does not close on finalize | |
// (see bug 777715) | |
this._fdmsg = fdmsg; | |
this._closeResult = null; | |
this._closed = null; | |
}; | |
File.prototype = { | |
/** | |
* Close a file asynchronously. | |
* | |
* This method is idempotent. | |
* | |
* @return {promise} | |
* @resolves {null} | |
* @rejects {OS.File.Error} | |
*/ | |
close: function close() { | |
if (this._fdmsg != null) { | |
let msg = this._fdmsg; | |
this._fdmsg = null; | |
return (this._closeResult = Scheduler.post( | |
"File_prototype_close", | |
[msg], | |
this | |
)); | |
} | |
return this._closeResult; | |
}, | |
/** | |
* Fetch information about the file. | |
* | |
* @return {promise} | |
* @resolves {OS.File.Info} The latest information about the file. | |
* @rejects {OS.File.Error} | |
*/ | |
stat: function stat() { | |
return Scheduler.post("File_prototype_stat", [this._fdmsg], this).then( | |
File.Info.fromMsg | |
); | |
}, | |
/** | |
* Write bytes from a buffer to this file. | |
* | |
* Note that, by default, this function may perform several I/O | |
* operations to ensure that the buffer is fully written. | |
* | |
* @param {Typed array | C pointer} buffer The buffer in which the | |
* the bytes are stored. The buffer must be large enough to | |
* accomodate |bytes| bytes. Using the buffer before the operation | |
* is complete is a BAD IDEA. | |
* @param {*=} options Optionally, an object that may contain the | |
* following fields: | |
* - {number} bytes The number of |bytes| to write from the buffer. If | |
* unspecified, this is |buffer.byteLength|. Note that |bytes| is required | |
* if |buffer| is a C pointer. | |
* | |
* @return {number} The number of bytes actually written. | |
*/ | |
write: function write(buffer, options = {}) { | |
// If |buffer| is a typed array and there is no |bytes| options, | |
// we need to extract the |byteLength| now, as it will be lost | |
// by communication. | |
// Options might be a nullish value, so better check for that before using | |
// the |in| operator. | |
if (isTypedArray(buffer) && !(options && "bytes" in options)) { | |
// Preserve reference to option |outExecutionDuration|, |outSerializationDuration|, if it is passed. | |
options = clone(options, [ | |
"outExecutionDuration", | |
"outSerializationDuration", | |
]); | |
options.bytes = buffer.byteLength; | |
} | |
return Scheduler.post( | |
"File_prototype_write", | |
[this._fdmsg, Type.void_t.in_ptr.toMsg(buffer), options], | |
buffer /* Ensure that |buffer| is not gc-ed*/ | |
); | |
}, | |
/** | |
* Read bytes from this file to a new buffer. | |
* | |
* @param {number=} bytes If unspecified, read all the remaining bytes from | |
* this file. If specified, read |bytes| bytes, or less if the file does not | |
* contain that many bytes. | |
* @param {JSON} options | |
* @return {promise} | |
* @resolves {Uint8Array} An array containing the bytes read. | |
*/ | |
read: function read(nbytes, options = {}) { | |
let promise = Scheduler.post("File_prototype_read", [ | |
this._fdmsg, | |
nbytes, | |
options, | |
]); | |
return promise.then(function onSuccess(data) { | |
return new Uint8Array(data.buffer, data.byteOffset, data.byteLength); | |
}); | |
}, | |
/** | |
* Return the current position in the file, as bytes. | |
* | |
* @return {promise} | |
* @resolves {number} The current position in the file, | |
* as a number of bytes since the start of the file. | |
*/ | |
getPosition: function getPosition() { | |
return Scheduler.post("File_prototype_getPosition", [this._fdmsg]); | |
}, | |
/** | |
* Set the current position in the file, as bytes. | |
* | |
* @param {number} pos A number of bytes. | |
* @param {number} whence The reference position in the file, | |
* which may be either POS_START (from the start of the file), | |
* POS_END (from the end of the file) or POS_CUR (from the | |
* current position in the file). | |
* | |
* @return {promise} | |
*/ | |
setPosition: function setPosition(pos, whence) { | |
return Scheduler.post("File_prototype_setPosition", [ | |
this._fdmsg, | |
pos, | |
whence, | |
]); | |
}, | |
/** | |
* Flushes the file's buffers and causes all buffered data | |
* to be written. | |
* Disk flushes are very expensive and therefore should be used carefully, | |
* sparingly and only in scenarios where it is vital that data survives | |
* system crashes. Even though the function will be executed off the | |
* main-thread, it might still affect the overall performance of any running | |
* application. | |
* | |
* @return {promise} | |
*/ | |
flush: function flush() { | |
return Scheduler.post("File_prototype_flush", [this._fdmsg]); | |
}, | |
/** | |
* Set the file's access permissions. This does nothing on Windows. | |
* | |
* This operation is likely to fail if applied to a file that was | |
* not created by the currently running program (more precisely, | |
* if it was created by a program running under a different OS-level | |
* user account). It may also fail, or silently do nothing, if the | |
* filesystem containing the file does not support access permissions. | |
* | |
* @param {*=} options Object specifying the requested permissions: | |
* | |
* - {number} unixMode The POSIX file mode to set on the file. If omitted, | |
* the POSIX file mode is reset to the default used by |OS.file.open|. If | |
* specified, the permissions will respect the process umask as if they | |
* had been specified as arguments of |OS.File.open|, unless the | |
* |unixHonorUmask| parameter tells otherwise. | |
* - {bool} unixHonorUmask If omitted or true, any |unixMode| value is | |
* modified by the process umask, as |OS.File.open| would have done. If | |
* false, the exact value of |unixMode| will be applied. | |
*/ | |
setPermissions: function setPermissions(options = {}) { | |
return Scheduler.post("File_prototype_setPermissions", [ | |
this._fdmsg, | |
options, | |
]); | |
}, | |
}; | |
if (SharedAll.Constants.Sys.Name != "Android") { | |
/** | |
* Set the last access and modification date of the file. | |
* The time stamp resolution is 1 second at best, but might be worse | |
* depending on the platform. | |
* | |
* WARNING: This method is not implemented on Android/B2G. On Android/B2G, | |
* you should use File.setDates instead. | |
* | |
* @return {promise} | |
* @rejects {TypeError} | |
* @rejects {OS.File.Error} | |
*/ | |
File.prototype.setDates = function(accessDate, modificationDate) { | |
return Scheduler.post( | |
"File_prototype_setDates", | |
[this._fdmsg, accessDate, modificationDate], | |
this | |
); | |
}; | |
} | |
/** | |
* Open a file asynchronously. | |
* | |
* @return {promise} | |
* @resolves {OS.File} | |
* @rejects {OS.Error} | |
*/ | |
File.open = function open(path, mode, options) { | |
return Scheduler.post( | |
"open", | |
[Type.path.toMsg(path), mode, options], | |
path | |
).then(function onSuccess(msg) { | |
return new File(msg); | |
}); | |
}; | |
/** | |
* Creates and opens a file with a unique name. By default, generate a random HEX number and use it to create a unique new file name. | |
* | |
* @param {string} path The path to the file. | |
* @param {*=} options Additional options for file opening. This | |
* implementation interprets the following fields: | |
* | |
* - {number} humanReadable If |true|, create a new filename appending a decimal number. ie: filename-1.ext, filename-2.ext. | |
* If |false| use HEX numbers ie: filename-A65BC0.ext | |
* - {number} maxReadableNumber Used to limit the amount of tries after a failed | |
* file creation. Default is 20. | |
* | |
* @return {Object} contains A file object{file} and the path{path}. | |
* @throws {OS.File.Error} If the file could not be opened. | |
*/ | |
File.openUnique = function openUnique(path, options) { | |
return Scheduler.post( | |
"openUnique", | |
[Type.path.toMsg(path), options], | |
path | |
).then(function onSuccess(msg) { | |
return { | |
path: msg.path, | |
file: new File(msg.file), | |
}; | |
}); | |
}; | |
/** | |
* Get the information on the file. | |
* | |
* @return {promise} | |
* @resolves {OS.File.Info} | |
* @rejects {OS.Error} | |
*/ | |
File.stat = function stat(path, options) { | |
return Scheduler.post("stat", [Type.path.toMsg(path), options], path).then( | |
File.Info.fromMsg | |
); | |
}; | |
/** | |
* Set the last access and modification date of the file. | |
* The time stamp resolution is 1 second at best, but might be worse | |
* depending on the platform. | |
* | |
* @return {promise} | |
* @rejects {TypeError} | |
* @rejects {OS.File.Error} | |
*/ | |
File.setDates = function setDates(path, accessDate, modificationDate) { | |
return Scheduler.post( | |
"setDates", | |
[Type.path.toMsg(path), accessDate, modificationDate], | |
this | |
); | |
}; | |
/** | |
* Set the file's access permissions. This does nothing on Windows. | |
* | |
* This operation is likely to fail if applied to a file that was | |
* not created by the currently running program (more precisely, | |
* if it was created by a program running under a different OS-level | |
* user account). It may also fail, or silently do nothing, if the | |
* filesystem containing the file does not support access permissions. | |
* | |
* @param {string} path The path to the file. | |
* @param {*=} options Object specifying the requested permissions: | |
* | |
* - {number} unixMode The POSIX file mode to set on the file. If omitted, | |
* the POSIX file mode is reset to the default used by |OS.file.open|. If | |
* specified, the permissions will respect the process umask as if they | |
* had been specified as arguments of |OS.File.open|, unless the | |
* |unixHonorUmask| parameter tells otherwise. | |
* - {bool} unixHonorUmask If omitted or true, any |unixMode| value is | |
* modified by the process umask, as |OS.File.open| would have done. If | |
* false, the exact value of |unixMode| will be applied. | |
*/ | |
File.setPermissions = function setPermissions(path, options = {}) { | |
return Scheduler.post("setPermissions", [Type.path.toMsg(path), options]); | |
}; | |
/** | |
* Fetch the current directory | |
* | |
* @return {promise} | |
* @resolves {string} The current directory, as a path usable with OS.Path | |
* @rejects {OS.Error} | |
*/ | |
File.getCurrentDirectory = function getCurrentDirectory() { | |
return Scheduler.post("getCurrentDirectory").then(Type.path.fromMsg); | |
}; | |
/** | |
* Change the current directory | |
* | |
* @param {string} path The OS-specific path to the current directory. | |
* You should use the methods of OS.Path and the constants of OS.Constants.Path | |
* to build OS-specific paths in a portable manner. | |
* | |
* @return {promise} | |
* @resolves {null} | |
* @rejects {OS.Error} | |
*/ | |
File.setCurrentDirectory = function setCurrentDirectory(path) { | |
return Scheduler.post("setCurrentDirectory", [Type.path.toMsg(path)], path); | |
}; | |
/** | |
* Copy a file to a destination. | |
* | |
* @param {string} sourcePath The platform-specific path at which | |
* the file may currently be found. | |
* @param {string} destPath The platform-specific path at which the | |
* file should be copied. | |
* @param {*=} options An object which may contain the following fields: | |
* | |
* @option {bool} noOverwrite - If true, this function will fail if | |
* a file already exists at |destPath|. Otherwise, if this file exists, | |
* it will be erased silently. | |
* | |
* @rejects {OS.File.Error} In case of any error. | |
* | |
* General note: The behavior of this function is defined only when | |
* it is called on a single file. If it is called on a directory, the | |
* behavior is undefined and may not be the same across all platforms. | |
* | |
* General note: The behavior of this function with respect to metadata | |
* is unspecified. Metadata may or may not be copied with the file. The | |
* behavior may not be the same across all platforms. | |
*/ | |
File.copy = function copy(sourcePath, destPath, options) { | |
return Scheduler.post( | |
"copy", | |
[Type.path.toMsg(sourcePath), Type.path.toMsg(destPath), options], | |
[sourcePath, destPath] | |
); | |
}; | |
/** | |
* Move a file to a destination. | |
* | |
* @param {string} sourcePath The platform-specific path at which | |
* the file may currently be found. | |
* @param {string} destPath The platform-specific path at which the | |
* file should be moved. | |
* @param {*=} options An object which may contain the following fields: | |
* | |
* @option {bool} noOverwrite - If set, this function will fail if | |
* a file already exists at |destPath|. Otherwise, if this file exists, | |
* it will be erased silently. | |
* | |
* @returns {Promise} | |
* @rejects {OS.File.Error} In case of any error. | |
* | |
* General note: The behavior of this function is defined only when | |
* it is called on a single file. If it is called on a directory, the | |
* behavior is undefined and may not be the same across all platforms. | |
* | |
* General note: The behavior of this function with respect to metadata | |
* is unspecified. Metadata may or may not be moved with the file. The | |
* behavior may not be the same across all platforms. | |
*/ | |
File.move = function move(sourcePath, destPath, options) { | |
return Scheduler.post( | |
"move", | |
[Type.path.toMsg(sourcePath), Type.path.toMsg(destPath), options], | |
[sourcePath, destPath] | |
); | |
}; | |
/** | |
* Create a symbolic link to a source. | |
* | |
* @param {string} sourcePath The platform-specific path to which | |
* the symbolic link should point. | |
* @param {string} destPath The platform-specific path at which the | |
* symbolic link should be created. | |
* | |
* @returns {Promise} | |
* @rejects {OS.File.Error} In case of any error. | |
*/ | |
if (!SharedAll.Constants.Win) { | |
File.unixSymLink = function unixSymLink(sourcePath, destPath) { | |
return Scheduler.post( | |
"unixSymLink", | |
[Type.path.toMsg(sourcePath), Type.path.toMsg(destPath)], | |
[sourcePath, destPath] | |
); | |
}; | |
} | |
/** | |
* Remove an empty directory. | |
* | |
* @param {string} path The name of the directory to remove. | |
* @param {*=} options Additional options. | |
* - {bool} ignoreAbsent If |true|, do not fail if the | |
* directory does not exist yet. | |
*/ | |
File.removeEmptyDir = function removeEmptyDir(path, options) { | |
return Scheduler.post( | |
"removeEmptyDir", | |
[Type.path.toMsg(path), options], | |
path | |
); | |
}; | |
/** | |
* Remove an existing file. | |
* | |
* @param {string} path The name of the file. | |
* @param {*=} options Additional options. | |
* - {bool} ignoreAbsent If |false|, throw an error if the file does | |
* not exist. |true| by default. | |
* | |
* @throws {OS.File.Error} In case of I/O error. | |
*/ | |
File.remove = function remove(path, options) { | |
return Scheduler.post("remove", [Type.path.toMsg(path), options], path); | |
}; | |
// Extended attribute functions are MacOS only at this point. | |
if (SharedAll.Constants.Sys.Name == "Darwin") { | |
/** | |
* Get an extended attribute (xattr) from a file. | |
* | |
* @param {string} path The name of the file. | |
* @param {string} name The name of the extended attribute. | |
* | |
* @returns {promise} | |
* @resolves {Uint8Array} An array containing the value of the attribute. | |
* @rejects {OS.File.Error} In case of an I/O error or invalid options. | |
*/ | |
File.macGetXAttr = function macGetXAttr(path, name) { | |
let promise = Scheduler.post( | |
"macGetXAttr", | |
[Type.path.toMsg(path), Type.cstring.toMsg(name)], | |
[path, name] | |
); | |
return promise.then(data => { | |
return new Uint8Array(data.buffer, data.byteOffset, data.byteLength); | |
}); | |
}; | |
/** | |
* Remove an extended attribute (xattr) from a file. | |
* | |
* @param {string} path The name of the file. | |
* @param {string} name The name of the extended attribute. | |
* | |
* @returns {promise} | |
* @resolves {null} | |
* @rejects {OS.File.Error} In case of an I/O error. | |
*/ | |
File.macRemoveXAttr = function macRemoveXAttr(path, name) { | |
return Scheduler.post( | |
"macRemoveXAttr", | |
[Type.path.toMsg(path), Type.cstring.toMsg(name)], | |
[path, name] | |
); | |
}; | |
/** | |
* Set an extended attribute (xattr) on a file. | |
* | |
* @param {string} path The name of the file. | |
* @param {string} name The name of the extended attribute. | |
* @param {Uint8Array} value A byte array containing the value to set the | |
* xattr to. | |
* | |
* @returns {promise} | |
* @resolves {null} | |
* @rejects {OS.File.Error} In case of an I/O error. | |
*/ | |
File.macSetXAttr = function macSetXAttr(path, name, value, number) { | |
return Scheduler.post( | |
"macSetXAttr", | |
[ | |
Type.path.toMsg(path), | |
Type.cstring.toMsg(name), | |
Type.void_t.in_ptr.toMsg(value), | |
value.length, | |
], | |
[path, name, value] | |
); | |
}; | |
} | |
/** | |
* Create a directory and, optionally, its parent directories. | |
* | |
* @param {string} path The name of the directory. | |
* @param {*=} options Additional options. | |
* | |
* - {string} from If specified, the call to |makeDir| creates all the | |
* ancestors of |path| that are descendants of |from|. Note that |path| | |
* must be a descendant of |from|, and that |from| and its existing | |
* subdirectories present in |path| must be user-writeable. | |
* Example: | |
* makeDir(Path.join(profileDir, "foo", "bar"), { from: profileDir }); | |
* creates directories profileDir/foo, profileDir/foo/bar | |
* - {bool} ignoreExisting If |false|, throw an error if the directory | |
* already exists. |true| by default. Ignored if |from| is specified. | |
* - {number} unixMode Under Unix, if specified, a file creation mode, | |
* as per libc function |mkdir|. If unspecified, dirs are | |
* created with a default mode of 0700 (dir is private to | |
* the user, the user can read, write and execute). Ignored under Windows | |
* or if the file system does not support file creation modes. | |
* - {C pointer} winSecurity Under Windows, if specified, security | |
* attributes as per winapi function |CreateDirectory|. If | |
* unspecified, use the default security descriptor, inherited from | |
* the parent directory. Ignored under Unix or if the file system | |
* does not support security descriptors. | |
*/ | |
File.makeDir = function makeDir(path, options) { | |
return Scheduler.post("makeDir", [Type.path.toMsg(path), options], path); | |
}; | |
/** | |
* Return the contents of a file | |
* | |
* @param {string} path The path to the file. | |
* @param {number=} bytes Optionally, an upper bound to the number of bytes | |
* to read. DEPRECATED - please use options.bytes instead. | |
* @param {JSON} options Additional options. | |
* - {boolean} sequential A flag that triggers a population of the page cache | |
* with data from a file so that subsequent reads from that file would not | |
* block on disk I/O. If |true| or unspecified, inform the system that the | |
* contents of the file will be read in order. Otherwise, make no such | |
* assumption. |true| by default. | |
* - {number} bytes An upper bound to the number of bytes to read. | |
* - {string} compression If "lz4" and if the file is compressed using the lz4 | |
* compression algorithm, decompress the file contents on the fly. | |
* | |
* @resolves {Uint8Array} A buffer holding the bytes | |
* read from the file. | |
*/ | |
File.read = function read(path, bytes, options = {}) { | |
if (typeof bytes == "object") { | |
// Passing |bytes| as an argument is deprecated. | |
// We should now be passing it as a field of |options|. | |
options = bytes || {}; | |
} else { | |
options = clone(options, [ | |
"outExecutionDuration", | |
"outSerializationDuration", | |
]); | |
if (typeof bytes != "undefined") { | |
options.bytes = bytes; | |
} | |
} | |
if (options.compression || !nativeWheneverAvailable) { | |
// We need to use the JS implementation. | |
let promise = Scheduler.post( | |
"read", | |
[Type.path.toMsg(path), bytes, options], | |
path | |
); | |
return promise.then(function onSuccess(data) { | |
if (typeof data == "string") { | |
return data; | |
} | |
return new Uint8Array(data.buffer, data.byteOffset, data.byteLength); | |
}); | |
} | |
// Otherwise, use the native implementation. | |
return Scheduler.push(() => Native.read(path, options)); | |
}; | |
/** | |
* Find outs if a file exists. | |
* | |
* @param {string} path The path to the file. | |
* | |
* @return {bool} true if the file exists, false otherwise. | |
*/ | |
File.exists = function exists(path) { | |
return Scheduler.post("exists", [Type.path.toMsg(path)], path); | |
}; | |
/** | |
* Write a file, atomically. | |
* | |
* By opposition to a regular |write|, this operation ensures that, | |
* until the contents are fully written, the destination file is | |
* not modified. | |
* | |
* Limitation: In a few extreme cases (hardware failure during the | |
* write, user unplugging disk during the write, etc.), data may be | |
* corrupted. If your data is user-critical (e.g. preferences, | |
* application data, etc.), you may wish to consider adding options | |
* |tmpPath| and/or |flush| to reduce the likelihood of corruption, as | |
* detailed below. Note that no combination of options can be | |
* guaranteed to totally eliminate the risk of corruption. | |
* | |
* @param {string} path The path of the file to modify. | |
* @param {Typed Array | C pointer} buffer A buffer containing the bytes to write. | |
* @param {*=} options Optionally, an object determining the behavior | |
* of this function. This object may contain the following fields: | |
* - {number} bytes The number of bytes to write. If unspecified, | |
* |buffer.byteLength|. Required if |buffer| is a C pointer. | |
* - {string} tmpPath If |null| or unspecified, write all data directly | |
* to |path|. If specified, write all data to a temporary file called | |
* |tmpPath| and, once this write is complete, rename the file to | |
* replace |path|. Performing this additional operation is a little | |
* slower but also a little safer. | |
* - {bool} noOverwrite - If set, this function will fail if a file already | |
* exists at |path|. | |
* - {bool} flush - If |false| or unspecified, return immediately once the | |
* write is complete. If |true|, before writing, force the operating system | |
* to write its internal disk buffers to the disk. This is considerably slower | |
* (not just for the application but for the whole system) but also safer: | |
* if the system shuts down improperly (typically due to a kernel freeze | |
* or a power failure) or if the device is disconnected before the buffer | |
* is flushed, the file has more chances of not being corrupted. | |
* - {string} backupTo - If specified, backup the destination file as |backupTo|. | |
* Note that this function renames the destination file before overwriting it. | |
* If the process or the operating system freezes or crashes | |
* during the short window between these operations, | |
* the destination file will have been moved to its backup. | |
* | |
* @return {promise} | |
* @resolves {number} The number of bytes actually written. | |
*/ | |
File.writeAtomic = function writeAtomic(path, buffer, options = {}) { | |
const useNativeImplementation = | |
nativeWheneverAvailable && | |
!options.compression && | |
!(isTypedArray(buffer) && "byteOffset" in buffer && buffer.byteOffset > 0); | |
// Copy |options| to avoid modifying the original object but preserve the | |
// reference to |outExecutionDuration|, |outSerializationDuration| option if it is passed. | |
options = clone(options, [ | |
"outExecutionDuration", | |
"outSerializationDuration", | |
]); | |
// As options.tmpPath is a path, we need to encode it as |Type.path| message, but only | |
// if we are not using the native implementation. | |
if ("tmpPath" in options && !useNativeImplementation) { | |
options.tmpPath = Type.path.toMsg(options.tmpPath); | |
} | |
if (isTypedArray(buffer) && !("bytes" in options)) { | |
options.bytes = buffer.byteLength; | |
} | |
let refObj = {}; | |
let promise; | |
TelemetryStopwatch.start("OSFILE_WRITEATOMIC_JANK_MS", refObj); | |
if (useNativeImplementation) { | |
promise = Scheduler.push(() => Native.writeAtomic(path, buffer, options)); | |
} else { | |
promise = Scheduler.post( | |
"writeAtomic", | |
[Type.path.toMsg(path), Type.void_t.in_ptr.toMsg(buffer), options], | |
[options, buffer, path] | |
); | |
} | |
TelemetryStopwatch.finish("OSFILE_WRITEATOMIC_JANK_MS", refObj); | |
return promise; | |
}; | |
File.removeDir = function(path, options = {}) { | |
return Scheduler.post("removeDir", [Type.path.toMsg(path), options], path); | |
}; | |
/** | |
* Information on a file, as returned by OS.File.stat or | |
* OS.File.prototype.stat | |
* | |
* @constructor | |
*/ | |
File.Info = function Info(value) { | |
// Note that we can't just do this[k] = value[k] because our | |
// prototype defines getters for all of these fields. | |
for (let k in value) { | |
if (k != "creationDate") { | |
Object.defineProperty(this, k, { value: value[k] }); | |
} | |
} | |
Object.defineProperty(this, "_deprecatedCreationDate", { | |
value: value.creationDate, | |
}); | |
}; | |
File.Info.prototype = SysAll.AbstractInfo.prototype; | |
// Deprecated | |
Object.defineProperty(File.Info.prototype, "creationDate", { | |
get: function creationDate() { | |
let { Deprecated } = ChromeUtils.import( | |
"resource://gre/modules/Deprecated.jsm" | |
); | |
Deprecated.warning( | |
"Field 'creationDate' is deprecated.", | |
"https://developer.mozilla.org/en-US/docs/JavaScript_OS.File/OS.File.Info#Cross-platform_Attributes" | |
); | |
return this._deprecatedCreationDate; | |
}, | |
}); | |
File.Info.fromMsg = function fromMsg(value) { | |
return new File.Info(value); | |
}; | |
/** | |
* Get worker's current DEBUG flag. | |
* Note: This is used for testing purposes. | |
*/ | |
File.GET_DEBUG = function GET_DEBUG() { | |
return Scheduler.post("GET_DEBUG"); | |
}; | |
/** | |
* Iterate asynchronously through a directory | |
* | |
* @constructor | |
*/ | |
var DirectoryIterator = function DirectoryIterator(path, options) { | |
/** | |
* Open the iterator on the worker thread | |
* | |
* @type {Promise} | |
* @resolves {*} A message accepted by the methods of DirectoryIterator | |
* in the worker thread | |
*/ | |
this._itmsg = Scheduler.post( | |
"new_DirectoryIterator", | |
[Type.path.toMsg(path), options], | |
path | |
); | |
this._isClosed = false; | |
}; | |
DirectoryIterator.prototype = { | |
[Symbol.asyncIterator]() { | |
return this; | |
}, | |
_itmsg: null, | |
/** | |
* Determine whether the directory exists. | |
* | |
* @resolves {boolean} | |
*/ | |
async exists() { | |
if (this._isClosed) { | |
return Promise.resolve(false); | |
} | |
let iterator = await this._itmsg; | |
return Scheduler.post("DirectoryIterator_prototype_exists", [iterator]); | |
}, | |
/** | |
* Get the next entry in the directory. | |
* | |
* @return {Promise} | |
* @resolves By definition of the async iterator protocol, either | |
* `{value: {File.Entry}, done: false}` if there is an unvisited entry | |
* in the directory, or `{value: undefined, done: true}`, otherwise. | |
*/ | |
async next() { | |
if (this._isClosed) { | |
return { value: undefined, done: true }; | |
} | |
return this._next(await this._itmsg); | |
}, | |
/** | |
* Get several entries at once. | |
* | |
* @param {number=} length If specified, the number of entries | |
* to return. If unspecified, return all remaining entries. | |
* @return {Promise} | |
* @resolves {Array} An array containing the |length| next entries. | |
*/ | |
async nextBatch(size) { | |
if (this._isClosed) { | |
return []; | |
} | |
let iterator = await this._itmsg; | |
let array = await Scheduler.post("DirectoryIterator_prototype_nextBatch", [ | |
iterator, | |
size, | |
]); | |
return array.map(DirectoryIterator.Entry.fromMsg); | |
}, | |
/** | |
* Apply a function to all elements of the directory sequentially. | |
* | |
* @param {Function} cb This function will be applied to all entries | |
* of the directory. It receives as arguments | |
* - the OS.File.Entry corresponding to the entry; | |
* - the index of the entry in the enumeration; | |
* - the iterator itself - return |iterator.close()| to stop the loop. | |
* | |
* If the callback returns a promise, iteration waits until the | |
* promise is resolved before proceeding. | |
* | |
* @return {Promise} A promise resolved once the loop has reached | |
* its end. | |
*/ | |
async forEach(cb, options) { | |
if (this._isClosed) { | |
return undefined; | |
} | |
let position = 0; | |
let iterator = await this._itmsg; | |
while (true) { | |
if (this._isClosed) { | |
return undefined; | |
} | |
let { value, done } = await this._next(iterator); | |
if (done) { | |
return undefined; | |
} | |
await cb(value, position++, this); | |
} | |
}, | |
/** | |
* Auxiliary method: fetch the next item | |
* | |
* @resolves `{value: undefined, done: true}` If all entries have already | |
* been visited or the iterator has been closed. | |
*/ | |
async _next(iterator) { | |
if (this._isClosed) { | |
return { value: undefined, done: true }; | |
} | |
let { value, done } = await Scheduler.post( | |
"DirectoryIterator_prototype_next", | |
[iterator] | |
); | |
if (done) { | |
this.close(); | |
return { value: undefined, done: true }; | |
} | |
return { value: DirectoryIterator.Entry.fromMsg(value), done: false }; | |
}, | |
/** | |
* Close the iterator | |
*/ | |
async close() { | |
if (this._isClosed) { | |
return undefined; | |
} | |
this._isClosed = true; | |
let iterator = this._itmsg; | |
this._itmsg = null; | |
return Scheduler.post("DirectoryIterator_prototype_close", [iterator]); | |
}, | |
}; | |
DirectoryIterator.Entry = function Entry(value) { | |
return value; | |
}; | |
DirectoryIterator.Entry.prototype = Object.create( | |
SysAll.AbstractEntry.prototype | |
); | |
DirectoryIterator.Entry.fromMsg = function fromMsg(value) { | |
return new DirectoryIterator.Entry(value); | |
}; | |
File.resetWorker = function() { | |
return (async function() { | |
let resources = await Scheduler.kill({ shutdown: false, reset: true }); | |
if (resources && !resources.killed) { | |
throw new Error( | |
"Could not reset worker, this would leak file descriptors: " + | |
JSON.stringify(resources) | |
); | |
} | |
})(); | |
}; | |
// Constants | |
File.POS_START = SysAll.POS_START; | |
File.POS_CURRENT = SysAll.POS_CURRENT; | |
File.POS_END = SysAll.POS_END; | |
// Exports | |
File.Error = OSError; | |
File.DirectoryIterator = DirectoryIterator; | |
var OS = {}; | |
this.OS.File = File; | |
this.OS.Constants = SharedAll.Constants; | |
this.OS.Shared = { | |
LOG: SharedAll.LOG, | |
Type: SysAll.Type, | |
get DEBUG() { | |
return SharedAll.Config.DEBUG; | |
}, | |
set DEBUG(x) { | |
return (SharedAll.Config.DEBUG = x); | |
}, | |
}; | |
Object.freeze(this.OS.Shared); | |
this.OS.Path = Path; | |
// Returns a resolved promise when all the queued operation have been completed. | |
Object.defineProperty(OS.File, "queue", { | |
get() { | |
return Scheduler.queue; | |
}, | |
}); | |
// `true` if this is a content process, `false` otherwise. | |
// It would be nicer to go through `Services.appinfo`, but some tests need to be | |
// able to replace that field with a custom implementation before it is first | |
// called. | |
const isContent = | |
// eslint-disable-next-line mozilla/use-services | |
Cc["@mozilla.org/xre/app-info;1"].getService(Ci.nsIXULRuntime).processType == | |
Ci.nsIXULRuntime.PROCESS_TYPE_CONTENT; | |
/** | |
* Shutdown barriers, to let clients register to be informed during shutdown. | |
*/ | |
var Barriers = { | |
shutdown: new AsyncShutdown.Barrier( | |
"OS.File: Waiting for clients before full shutdown" | |
), | |
/** | |
* Return the shutdown state of OS.File | |
*/ | |
getDetails() { | |
let result = { | |
launched: Scheduler.launched, | |
shutdown: Scheduler.shutdown, | |
worker: !!Scheduler._worker, | |
pendingReset: !!Scheduler.resetTimer, | |
latestSent: Scheduler.Debugging.latestSent, | |
latestReceived: Scheduler.Debugging.latestReceived, | |
messagesSent: Scheduler.Debugging.messagesSent, | |
messagesReceived: Scheduler.Debugging.messagesReceived, | |
messagesQueued: Scheduler.Debugging.messagesQueued, | |
DEBUG: SharedAll.Config.DEBUG, | |
}; | |
// Convert dates to strings for better readability | |
for (let key of ["latestSent", "latestReceived"]) { | |
if (result[key] && typeof result[key][0] == "number") { | |
result[key][0] = Date(result[key][0]); | |
} | |
} | |
return result; | |
}, | |
}; | |
function setupShutdown(phaseName) { | |
Barriers[phaseName] = new AsyncShutdown.Barrier( | |
`OS.File: Waiting for clients before ${phaseName}` | |
); | |
File[phaseName] = Barriers[phaseName].client; | |
// Auto-flush OS.File during `phaseName`. This ensures that any I/O | |
// that has been queued *before* `phaseName` is properly completed. | |
// To ensure that I/O queued *during* `phaseName` change is completed, | |
// clients should register using AsyncShutdown.addBlocker. | |
AsyncShutdown[phaseName].addBlocker( | |
`OS.File: flush I/O queued before ${phaseName}`, | |
async function() { | |
// Give clients a last chance to enqueue requests. | |
await Barriers[phaseName].wait({ crashAfterMS: null }); | |
// Wait until all currently enqueued requests are completed. | |
await Scheduler.queue; | |
}, | |
() => { | |
let details = Barriers.getDetails(); | |
details.clients = Barriers[phaseName].state; | |
return details; | |
} | |
); | |
} | |
// profile-before-change only exists in the parent, and OS.File should | |
// not be used in the child process anyways. | |
if (!isContent) { | |
setupShutdown("profileBeforeChange"); | |
} | |
File.shutdown = Barriers.shutdown.client; |
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