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/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* 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/. */
var EXPORTED_SYMBOLS = ["FileUtils"];
const lazy = {};
ChromeUtils.defineModuleGetter(
lazy,
"Deprecated",
);
var FileUtils = {
MODE_RDONLY: 0x01,
MODE_WRONLY: 0x02,
MODE_RDWR: 0x04,
MODE_CREATE: 0x08,
MODE_APPEND: 0x10,
MODE_TRUNCATE: 0x20,
PERMS_FILE: 0o644,
PERMS_DIRECTORY: 0o755,
/**
* Gets a file at the specified hierarchy under a nsIDirectoryService key.
* @param key
* The Directory Service Key to start from
* @param pathArray
* An array of path components to locate beneath the directory
* specified by |key|. The last item in this array must be the
* leaf name of a file.
* @return nsIFile object for the file specified. The file is NOT created
* if it does not exist, however all required directories along
* the way are if pathArray has more than one item.
*/
getFile: function FileUtils_getFile(key, pathArray) {
var file = this.getDir(key, pathArray.slice(0, -1), pathArray.length > 1);
file.append(pathArray[pathArray.length - 1]);
return file;
},
/**
* Gets a directory at the specified hierarchy under a nsIDirectoryService
* key.
* @param key
* The Directory Service Key to start from
* @param pathArray
* An array of path components to locate beneath the directory
* specified by |key|
* @param shouldCreate
* true if the directory hierarchy specified in |pathArray|
* should be created if it does not exist, false otherwise.
* @return nsIFile object for the location specified.
*/
getDir: function FileUtils_getDir(key, pathArray, shouldCreate) {
var dir = Services.dirsvc.get(key, Ci.nsIFile);
for (var i = 0; i < pathArray.length; ++i) {
dir.append(pathArray[i]);
}
if (shouldCreate) {
if (Services.startup.startingUp || Services.startup.shuttingDown) {
lazy.Deprecated.warning(
"Calling FileUtils.getDir(..., ..., true) causes main thread I/O and should be avoided especially during startup/shutdown",
);
}
try {
dir.create(Ci.nsIFile.DIRECTORY_TYPE, this.PERMS_DIRECTORY);
} catch (ex) {
if (ex.result != Cr.NS_ERROR_FILE_ALREADY_EXISTS) {
throw ex;
}
// Ignore the exception due to a directory that already exists.
}
}
return dir;
},
/**
* Opens a file output stream for writing.
* @param file
* The file to write to.
* @param modeFlags
* (optional) File open flags. Can be undefined.
* @returns nsIFileOutputStream to write to.
* @note The stream is initialized with the DEFER_OPEN behavior flag.
* See nsIFileOutputStream.
*/
openFileOutputStream: function FileUtils_openFileOutputStream(
file,
modeFlags
) {
var fos = Cc["@mozilla.org/network/file-output-stream;1"].createInstance(
Ci.nsIFileOutputStream
);
return this._initFileOutputStream(fos, file, modeFlags);
},
/**
* Opens an atomic file output stream for writing.
* @param file
* The file to write to.
* @param modeFlags
* (optional) File open flags. Can be undefined.
* @returns nsIFileOutputStream to write to.
* @note The stream is initialized with the DEFER_OPEN behavior flag.
* See nsIFileOutputStream.
* OpeanAtomicFileOutputStream is generally better than openSafeFileOutputStream
* baecause flushing is not needed in most of the issues.
*/
openAtomicFileOutputStream: function FileUtils_openAtomicFileOutputStream(
file,
modeFlags
) {
var fos = Cc[
"@mozilla.org/network/atomic-file-output-stream;1"
].createInstance(Ci.nsIFileOutputStream);
return this._initFileOutputStream(fos, file, modeFlags);
},
/**
* Opens a safe file output stream for writing.
* @param file
* The file to write to.
* @param modeFlags
* (optional) File open flags. Can be undefined.
* @returns nsIFileOutputStream to write to.
* @note The stream is initialized with the DEFER_OPEN behavior flag.
* See nsIFileOutputStream.
*/
openSafeFileOutputStream: function FileUtils_openSafeFileOutputStream(
file,
modeFlags
) {
var fos = Cc[
"@mozilla.org/network/safe-file-output-stream;1"
].createInstance(Ci.nsIFileOutputStream);
return this._initFileOutputStream(fos, file, modeFlags);
},
_initFileOutputStream: function FileUtils__initFileOutputStream(
fos,
file,
modeFlags
) {
if (modeFlags === undefined) {
modeFlags = this.MODE_WRONLY | this.MODE_CREATE | this.MODE_TRUNCATE;
}
fos.init(file, modeFlags, this.PERMS_FILE, fos.DEFER_OPEN);
return fos;
},
/**
* Closes an atomic file output stream.
* @param stream
* The stream to close.
*/
closeAtomicFileOutputStream: function FileUtils_closeAtomicFileOutputStream(
stream
) {
if (stream instanceof Ci.nsISafeOutputStream) {
try {
stream.finish();
return;
} catch (e) {}
}
stream.close();
},
/**
* Closes a safe file output stream.
* @param stream
* The stream to close.
*/
closeSafeFileOutputStream: function FileUtils_closeSafeFileOutputStream(
stream
) {
if (stream instanceof Ci.nsISafeOutputStream) {
try {
stream.finish();
return;
} catch (e) {}
}
stream.close();
},
File: Components.Constructor(
"@mozilla.org/file/local;1",
Ci.nsIFile,
"initWithPath"
),
};