0
0
mirror of https://github.com/nodejs/node.git synced 2024-11-30 07:27:22 +01:00
nodejs/lib/fs.js
isaacs c75f71dd72 fs.WriteStream: Handle modifications to fs.open
If the fs.open method is modified via AOP-style extension, in between
the creation of an fs.WriteStream and the processing of its action
queue, then the test of whether or not the method === fs.open will fail,
because fs.open has been replaced.

The solution is to save a reference to fs.open on the stream itself when
the action is placed in the queue.

This fixes isaacs/node-graceful-fs#6.
2012-04-09 09:03:00 -07:00

1456 lines
35 KiB
JavaScript

// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
// Maintainers, keep in mind that octal literals are not allowed
// in strict mode. Use the decimal value and add a comment with
// the octal value. Example:
//
// var mode = 438; /* mode=0666 */
var util = require('util');
var pathModule = require('path');
var binding = process.binding('fs');
var constants = process.binding('constants');
var fs = exports;
var Stream = require('stream').Stream;
var EventEmitter = require('events').EventEmitter;
var kMinPoolSpace = 128;
var kPoolSize = 40 * 1024;
fs.Stats = binding.Stats;
fs.Stats.prototype._checkModeProperty = function(property) {
return ((this.mode & constants.S_IFMT) === property);
};
fs.Stats.prototype.isDirectory = function() {
return this._checkModeProperty(constants.S_IFDIR);
};
fs.Stats.prototype.isFile = function() {
return this._checkModeProperty(constants.S_IFREG);
};
fs.Stats.prototype.isBlockDevice = function() {
return this._checkModeProperty(constants.S_IFBLK);
};
fs.Stats.prototype.isCharacterDevice = function() {
return this._checkModeProperty(constants.S_IFCHR);
};
fs.Stats.prototype.isSymbolicLink = function() {
return this._checkModeProperty(constants.S_IFLNK);
};
fs.Stats.prototype.isFIFO = function() {
return this._checkModeProperty(constants.S_IFIFO);
};
fs.Stats.prototype.isSocket = function() {
return this._checkModeProperty(constants.S_IFSOCK);
};
fs.readFile = function(path, encoding_) {
var encoding = typeof(encoding_) === 'string' ? encoding_ : null;
var callback = arguments[arguments.length - 1];
if (typeof(callback) !== 'function') callback = noop;
var readStream = fs.createReadStream(path);
var buffers = [];
var nread = 0;
var error;
readStream.on('data', function(chunk) {
buffers.push(chunk);
nread += chunk.length;
});
readStream.on('error', function(er) {
error = er;
readStream.destroy();
if (!readStream.fd) {
readStream.emit('close');
}
});
readStream.on('close', function() {
if (error) {
return callback(error);
}
// copy all the buffers into one
var buffer;
switch (buffers.length) {
case 0: buffer = new Buffer(0); break;
case 1: buffer = buffers[0]; break;
default: // concat together
buffer = new Buffer(nread);
var n = 0;
buffers.forEach(function(b) {
var l = b.length;
b.copy(buffer, n, 0, l);
n += l;
});
break;
}
if (encoding) {
try {
buffer = buffer.toString(encoding);
} catch (er) {
return callback(er);
}
}
callback(null, buffer);
});
};
fs.readFileSync = function(path, encoding) {
var fd = fs.openSync(path, constants.O_RDONLY, 438 /*=0666*/);
var buffer = new Buffer(4048);
var buffers = [];
var nread = 0;
var lastRead = 0;
do {
if (lastRead) {
buffer._bytesRead = lastRead;
nread += lastRead;
buffers.push(buffer);
}
var buffer = new Buffer(4048);
lastRead = fs.readSync(fd, buffer, 0, buffer.length, null);
} while (lastRead > 0);
fs.closeSync(fd);
if (buffers.length > 1) {
var offset = 0;
var i;
buffer = new Buffer(nread);
buffers.forEach(function(i) {
if (!i._bytesRead) return;
i.copy(buffer, offset, 0, i._bytesRead);
offset += i._bytesRead;
});
} else if (buffers.length) {
// buffers has exactly 1 (possibly zero length) buffer, so this should
// be a shortcut
buffer = buffers[0].slice(0, buffers[0]._bytesRead);
} else {
buffer = new Buffer(0);
}
if (encoding) buffer = buffer.toString(encoding);
return buffer;
};
// Used by binding.open and friends
function stringToFlags(flag) {
// Only mess with strings
if (typeof flag !== 'string') {
return flag;
}
switch (flag) {
case 'r':
return constants.O_RDONLY;
case 'r+':
return constants.O_RDWR;
case 'w':
return constants.O_CREAT | constants.O_TRUNC | constants.O_WRONLY;
case 'w+':
return constants.O_CREAT | constants.O_TRUNC | constants.O_RDWR;
case 'a':
return constants.O_APPEND | constants.O_CREAT | constants.O_WRONLY;
case 'a+':
return constants.O_APPEND | constants.O_CREAT | constants.O_RDWR;
default:
throw new Error('Unknown file open flag: ' + flag);
}
}
function noop() {}
// Yes, the follow could be easily DRYed up but I provide the explicit
// list to make the arguments clear.
fs.close = function(fd, callback) {
binding.close(fd, callback || noop);
};
fs.closeSync = function(fd) {
return binding.close(fd);
};
function modeNum(m, def) {
switch (typeof m) {
case 'number': return m;
case 'string': return parseInt(m, 8);
default:
if (def) {
return modeNum(def);
} else {
return undefined;
}
}
}
fs.open = function(path, flags, mode, callback) {
callback = arguments[arguments.length - 1];
if (typeof(callback) !== 'function') {
callback = noop;
}
mode = modeNum(mode, 438 /*=0666*/);
binding.open(pathModule._makeLong(path), stringToFlags(flags), mode,
callback);
};
fs.openSync = function(path, flags, mode) {
mode = modeNum(mode, 438 /*=0666*/);
return binding.open(pathModule._makeLong(path), stringToFlags(flags), mode);
};
fs.read = function(fd, buffer, offset, length, position, callback) {
if (!Buffer.isBuffer(buffer)) {
// legacy string interface (fd, length, position, encoding, callback)
var cb = arguments[4],
encoding = arguments[3];
position = arguments[2];
length = arguments[1];
buffer = new Buffer(length);
offset = 0;
callback = function(err, bytesRead) {
if (!cb) return;
var str = (bytesRead > 0) ? buffer.toString(encoding, 0, bytesRead) : '';
(cb)(err, str, bytesRead);
};
}
function wrapper(err, bytesRead) {
// Retain a reference to buffer so that it can't be GC'ed too soon.
callback && callback(err, bytesRead || 0, buffer);
}
binding.read(fd, buffer, offset, length, position, wrapper);
};
fs.readSync = function(fd, buffer, offset, length, position) {
var legacy = false;
if (!Buffer.isBuffer(buffer)) {
// legacy string interface (fd, length, position, encoding, callback)
legacy = true;
var encoding = arguments[3];
position = arguments[2];
length = arguments[1];
buffer = new Buffer(length);
offset = 0;
}
var r = binding.read(fd, buffer, offset, length, position);
if (!legacy) {
return r;
}
var str = (r > 0) ? buffer.toString(encoding, 0, r) : '';
return [str, r];
};
fs.write = function(fd, buffer, offset, length, position, callback) {
if (!Buffer.isBuffer(buffer)) {
// legacy string interface (fd, data, position, encoding, callback)
callback = arguments[4];
position = arguments[2];
buffer = new Buffer('' + arguments[1], arguments[3]);
offset = 0;
length = buffer.length;
}
if (!length) {
if (typeof callback == 'function') {
process.nextTick(function() {
callback(undefined, 0);
});
}
return;
}
function wrapper(err, written) {
// Retain a reference to buffer so that it can't be GC'ed too soon.
callback && callback(err, written || 0, buffer);
}
binding.write(fd, buffer, offset, length, position, wrapper);
};
fs.writeSync = function(fd, buffer, offset, length, position) {
if (!Buffer.isBuffer(buffer)) {
// legacy string interface (fd, data, position, encoding)
position = arguments[2];
buffer = new Buffer('' + arguments[1], arguments[3]);
offset = 0;
length = buffer.length;
}
if (!length) return 0;
return binding.write(fd, buffer, offset, length, position);
};
fs.rename = function(oldPath, newPath, callback) {
binding.rename(pathModule._makeLong(oldPath), pathModule._makeLong(newPath),
callback || noop);
};
fs.renameSync = function(oldPath, newPath) {
return binding.rename(pathModule._makeLong(oldPath),
pathModule._makeLong(newPath));
};
fs.truncate = function(fd, len, callback) {
binding.truncate(fd, len, callback || noop);
};
fs.truncateSync = function(fd, len) {
return binding.truncate(fd, len);
};
fs.rmdir = function(path, callback) {
binding.rmdir(pathModule._makeLong(path), callback || noop);
};
fs.rmdirSync = function(path) {
return binding.rmdir(pathModule._makeLong(path));
};
fs.fdatasync = function(fd, callback) {
binding.fdatasync(fd, callback || noop);
};
fs.fdatasyncSync = function(fd) {
return binding.fdatasync(fd);
};
fs.fsync = function(fd, callback) {
binding.fsync(fd, callback || noop);
};
fs.fsyncSync = function(fd) {
return binding.fsync(fd);
};
fs.mkdir = function(path, mode, callback) {
if (typeof mode === 'function') callback = mode;
binding.mkdir(pathModule._makeLong(path), modeNum(mode, 511 /*=0777*/),
callback || noop);
};
fs.mkdirSync = function(path, mode) {
return binding.mkdir(pathModule._makeLong(path),
modeNum(mode, 511 /*=0777*/));
};
fs.sendfile = function(outFd, inFd, inOffset, length, callback) {
binding.sendfile(outFd, inFd, inOffset, length, callback || noop);
};
fs.sendfileSync = function(outFd, inFd, inOffset, length) {
return binding.sendfile(outFd, inFd, inOffset, length);
};
fs.readdir = function(path, callback) {
binding.readdir(pathModule._makeLong(path), callback || noop);
};
fs.readdirSync = function(path) {
return binding.readdir(pathModule._makeLong(path));
};
fs.fstat = function(fd, callback) {
binding.fstat(fd, callback || noop);
};
fs.lstat = function(path, callback) {
binding.lstat(pathModule._makeLong(path), callback || noop);
};
fs.stat = function(path, callback) {
binding.stat(pathModule._makeLong(path), callback || noop);
};
fs.fstatSync = function(fd) {
return binding.fstat(fd);
};
fs.lstatSync = function(path) {
return binding.lstat(pathModule._makeLong(path));
};
fs.statSync = function(path) {
return binding.stat(pathModule._makeLong(path));
};
fs.readlink = function(path, callback) {
binding.readlink(pathModule._makeLong(path), callback || noop);
};
fs.readlinkSync = function(path) {
return binding.readlink(pathModule._makeLong(path));
};
fs.symlink = function(destination, path, type_, callback) {
var type = (typeof(type_) == 'string' ? type_ : null);
var callback_ = arguments[arguments.length - 1];
callback = (typeof(callback_) == 'function' ? callback_ : null);
binding.symlink(pathModule._makeLong(destination),
pathModule._makeLong(path), type, callback);
};
fs.symlinkSync = function(destination, path, type) {
return binding.symlink(pathModule._makeLong(destination),
pathModule._makeLong(path), type);
};
fs.link = function(srcpath, dstpath, callback) {
binding.link(pathModule._makeLong(srcpath), pathModule._makeLong(dstpath),
callback || noop);
};
fs.linkSync = function(srcpath, dstpath) {
return binding.link(pathModule._makeLong(srcpath),
pathModule._makeLong(dstpath));
};
fs.unlink = function(path, callback) {
binding.unlink(pathModule._makeLong(path), callback || noop);
};
fs.unlinkSync = function(path) {
return binding.unlink(pathModule._makeLong(path));
};
fs.fchmod = function(fd, mode, callback) {
binding.fchmod(fd, modeNum(mode), callback || noop);
};
fs.fchmodSync = function(fd, mode) {
return binding.fchmod(fd, modeNum(mode));
};
if (constants.hasOwnProperty('O_SYMLINK')) {
fs.lchmod = function(path, mode, callback) {
callback = callback || noop;
fs.open(path, constants.O_WRONLY | constants.O_SYMLINK, function(err, fd) {
if (err) {
callback(err);
return;
}
// prefer to return the chmod error, if one occurs,
// but still try to close, and report closing errors if they occur.
fs.fchmod(fd, mode, function(err) {
fs.close(fd, function(err2) {
callback(err || err2);
});
});
});
};
fs.lchmodSync = function(path, mode) {
var fd = fs.openSync(path, constants.O_WRONLY | constants.O_SYMLINK);
// prefer to return the chmod error, if one occurs,
// but still try to close, and report closing errors if they occur.
var err, err2;
try {
var ret = fs.fchmodSync(fd, mode);
} catch (er) {
err = er;
}
try {
fs.closeSync(fd);
} catch (er) {
err2 = er;
}
if (err || err2) throw (err || err2);
return ret;
};
}
fs.chmod = function(path, mode, callback) {
binding.chmod(pathModule._makeLong(path), modeNum(mode), callback || noop);
};
fs.chmodSync = function(path, mode) {
return binding.chmod(pathModule._makeLong(path), modeNum(mode));
};
if (constants.hasOwnProperty('O_SYMLINK')) {
fs.lchown = function(path, uid, gid, callback) {
callback = callback || noop;
fs.open(path, constants.O_WRONLY | constants.O_SYMLINK, function(err, fd) {
if (err) {
callback(err);
return;
}
fs.fchown(fd, uid, gid, callback);
});
};
fs.lchownSync = function(path, uid, gid) {
var fd = fs.openSync(path, constants.O_WRONLY | constants.O_SYMLINK);
return fs.fchownSync(fd, uid, gid);
};
}
fs.fchown = function(fd, uid, gid, callback) {
binding.fchown(fd, uid, gid, callback || noop);
};
fs.fchownSync = function(fd, uid, gid) {
return binding.fchown(fd, uid, gid);
};
fs.chown = function(path, uid, gid, callback) {
binding.chown(pathModule._makeLong(path), uid, gid, callback || noop);
};
fs.chownSync = function(path, uid, gid) {
return binding.chown(pathModule._makeLong(path), uid, gid);
};
// converts Date or number to a fractional UNIX timestamp
function toUnixTimestamp(time) {
if (typeof time == 'number') {
return time;
}
if (time instanceof Date) {
// convert to 123.456 UNIX timestamp
return time.getTime() / 1000;
}
throw new Error('Cannot parse time: ' + time);
}
// exported for unit tests, not for public consumption
fs._toUnixTimestamp = toUnixTimestamp;
fs.utimes = function(path, atime, mtime, callback) {
atime = toUnixTimestamp(atime);
mtime = toUnixTimestamp(mtime);
binding.utimes(pathModule._makeLong(path), atime, mtime, callback || noop);
};
fs.utimesSync = function(path, atime, mtime) {
atime = toUnixTimestamp(atime);
mtime = toUnixTimestamp(mtime);
binding.utimes(pathModule._makeLong(path), atime, mtime);
};
fs.futimes = function(fd, atime, mtime, callback) {
atime = toUnixTimestamp(atime);
mtime = toUnixTimestamp(mtime);
binding.futimes(fd, atime, mtime, callback || noop);
};
fs.futimesSync = function(fd, atime, mtime) {
atime = toUnixTimestamp(atime);
mtime = toUnixTimestamp(mtime);
binding.futimes(fd, atime, mtime);
};
function writeAll(fd, buffer, offset, length, callback) {
// write(fd, buffer, offset, length, position, callback)
fs.write(fd, buffer, offset, length, offset, function(writeErr, written) {
if (writeErr) {
fs.close(fd, function() {
if (callback) callback(writeErr);
});
} else {
if (written === length) {
fs.close(fd, callback);
} else {
writeAll(fd, buffer, offset + written, length - written, callback);
}
}
});
}
fs.writeFile = function(path, data, encoding_, callback) {
var encoding = (typeof(encoding_) == 'string' ? encoding_ : 'utf8');
var callback_ = arguments[arguments.length - 1];
callback = (typeof(callback_) == 'function' ? callback_ : null);
fs.open(path, 'w', 438 /*=0666*/, function(openErr, fd) {
if (openErr) {
if (callback) callback(openErr);
} else {
var buffer = Buffer.isBuffer(data) ? data : new Buffer('' + data,
encoding);
writeAll(fd, buffer, 0, buffer.length, callback);
}
});
};
fs.writeFileSync = function(path, data, encoding) {
var fd = fs.openSync(path, 'w');
if (!Buffer.isBuffer(data)) {
data = new Buffer('' + data, encoding || 'utf8');
}
var written = 0;
var length = data.length;
//writeSync(fd, buffer, offset, length, position)
while (written < length) {
written += fs.writeSync(fd, data, written, length - written, written);
}
fs.closeSync(fd);
};
function errnoException(errorno, syscall) {
// TODO make this more compatible with ErrnoException from src/node.cc
// Once all of Node is using this function the ErrnoException from
// src/node.cc should be removed.
var e = new Error(syscall + ' ' + errorno);
e.errno = e.code = errorno;
e.syscall = syscall;
return e;
}
function FSWatcher() {
var self = this;
var FSEvent = process.binding('fs_event_wrap').FSEvent;
this._handle = new FSEvent();
this._handle.onchange = function(status, event, filename) {
if (status) {
self.emit('error', errnoException(errno, 'watch'));
} else {
self.emit('change', event, filename);
}
};
}
util.inherits(FSWatcher, EventEmitter);
FSWatcher.prototype.start = function(filename, persistent) {
var r = this._handle.start(pathModule._makeLong(filename), persistent);
if (r) {
this._handle.close();
throw errnoException(errno, 'watch');
}
};
FSWatcher.prototype.close = function() {
this._handle.close();
};
fs.watch = function(filename) {
var watcher;
var options;
var listener;
if ('object' == typeof arguments[1]) {
options = arguments[1];
listener = arguments[2];
} else {
options = {};
listener = arguments[1];
}
if (!listener) {
throw new Error('watch requires a listener function');
}
if (options.persistent === undefined) options.persistent = true;
watcher = new FSWatcher();
watcher.start(filename, options.persistent);
watcher.addListener('change', listener);
return watcher;
};
// Stat Change Watchers
function StatWatcher() {
var self = this;
this._handle = new binding.StatWatcher();
this._handle.onchange = function(current, previous) {
self.emit('change', current, previous);
};
this._handle.onstop = function() {
self.emit('stop');
};
}
util.inherits(StatWatcher, EventEmitter);
StatWatcher.prototype.start = function(filename, persistent, interval) {
this._handle.start(pathModule._makeLong(filename), persistent, interval);
};
StatWatcher.prototype.stop = function() {
this._handle.stop();
};
var statWatchers = {};
function inStatWatchers(filename) {
return Object.prototype.hasOwnProperty.call(statWatchers, filename) &&
statWatchers[filename];
}
fs.watchFile = function(filename) {
if (isWindows) {
throw new Error('use fs.watch api instead');
}
var stat;
var options;
var listener;
if ('object' == typeof arguments[1]) {
options = arguments[1];
listener = arguments[2];
} else {
options = {};
listener = arguments[1];
}
if (!listener) {
throw new Error('watchFile requires a listener function');
}
if (options.persistent === undefined) options.persistent = true;
if (options.interval === undefined) options.interval = 0;
if (inStatWatchers(filename)) {
stat = statWatchers[filename];
} else {
stat = statWatchers[filename] = new StatWatcher();
stat.start(filename, options.persistent, options.interval);
}
stat.addListener('change', listener);
return stat;
};
fs.unwatchFile = function(filename) {
var stat;
if (inStatWatchers(filename)) {
stat = statWatchers[filename];
stat.stop();
statWatchers[filename] = undefined;
}
};
// Realpath
// Not using realpath(2) because it's bad.
// See: http://insanecoding.blogspot.com/2007/11/pathmax-simply-isnt.html
var normalize = pathModule.normalize,
isWindows = process.platform === 'win32';
if (isWindows) {
// Node doesn't support symlinks / lstat on windows. Hence realpath is just
// the same as path.resolve that fails if the path doesn't exists.
// windows version
fs.realpathSync = function realpathSync(p, cache) {
p = pathModule.resolve(p);
if (cache && Object.prototype.hasOwnProperty.call(cache, p)) {
return cache[p];
}
fs.statSync(p);
if (cache) cache[p] = p;
return p;
};
// windows version
fs.realpath = function(p, cache, cb) {
if (typeof cb !== 'function') {
cb = cache;
cache = null;
}
p = pathModule.resolve(p);
if (cache && Object.prototype.hasOwnProperty.call(cache, p)) {
return cb(null, cache[p]);
}
fs.stat(p, function(err) {
if (err) return cb(err);
if (cache) cache[p] = p;
cb(null, p);
});
};
} else /* posix */ {
// Regexp that finds the next partion of a (partial) path
// result is [base_with_slash, base], e.g. ['somedir/', 'somedir']
var nextPartRe = /(.*?)(?:[\/]+|$)/g;
// posix version
fs.realpathSync = function realpathSync(p, cache) {
// make p is absolute
p = pathModule.resolve(p);
if (cache && Object.prototype.hasOwnProperty.call(cache, p)) {
return cache[p];
}
var original = p,
seenLinks = {},
knownHard = {};
// current character position in p
var pos = 0;
// the partial path so far, including a trailing slash if any
var current = '';
// the partial path without a trailing slash
var base = '';
// the partial path scanned in the previous round, with slash
var previous = '';
// walk down the path, swapping out linked pathparts for their real
// values
// NB: p.length changes.
while (pos < p.length) {
// find the next part
nextPartRe.lastIndex = pos;
var result = nextPartRe.exec(p);
previous = current;
current += result[0];
base = previous + result[1];
pos = nextPartRe.lastIndex;
// continue if not a symlink, or if root
if (!base || knownHard[base] || (cache && cache[base] === base)) {
continue;
}
var resolvedLink;
if (cache && Object.prototype.hasOwnProperty.call(cache, base)) {
// some known symbolic link. no need to stat again.
resolvedLink = cache[base];
} else {
var stat = fs.lstatSync(base);
if (!stat.isSymbolicLink()) {
knownHard[base] = true;
if (cache) cache[base] = base;
continue;
}
// read the link if it wasn't read before
var id = stat.dev.toString(32) + ':' + stat.ino.toString(32);
if (!seenLinks[id]) {
fs.statSync(base);
seenLinks[id] = fs.readlinkSync(base);
resolvedLink = pathModule.resolve(previous, seenLinks[id]);
// track this, if given a cache.
if (cache) cache[base] = resolvedLink;
}
}
// resolve the link, then start over
p = pathModule.resolve(resolvedLink, p.slice(pos));
pos = 0;
previous = base = current = '';
}
if (cache) cache[original] = p;
return p;
};
// posix version
fs.realpath = function realpath(p, cache, cb) {
if (typeof cb !== 'function') {
cb = cache;
cache = null;
}
// make p is absolute
p = pathModule.resolve(p);
if (cache && Object.prototype.hasOwnProperty.call(cache, p)) {
return cb(null, cache[p]);
}
var original = p,
seenLinks = {},
knownHard = {};
// current character position in p
var pos = 0;
// the partial path so far, including a trailing slash if any
var current = '';
// the partial path without a trailing slash
var base = '';
// the partial path scanned in the previous round, with slash
var previous = '';
// walk down the path, swapping out linked pathparts for their real
// values
LOOP();
function LOOP() {
// stop if scanned past end of path
if (pos >= p.length) {
if (cache) cache[original] = p;
return cb(null, p);
}
// find the next part
nextPartRe.lastIndex = pos;
var result = nextPartRe.exec(p);
previous = current;
current += result[0];
base = previous + result[1];
pos = nextPartRe.lastIndex;
// continue if known to be hard or if root or in cache already.
if (!base || knownHard[base] || (cache && cache[base] === base)) {
return process.nextTick(LOOP);
}
if (cache && Object.prototype.hasOwnProperty.call(cache, base)) {
// known symbolic link. no need to stat again.
return gotResolvedLink(cache[base]);
}
return fs.lstat(base, gotStat);
}
function gotStat(err, stat) {
if (err) return cb(err);
// if not a symlink, skip to the next path part
if (!stat.isSymbolicLink()) {
knownHard[base] = true;
if (cache) cache[base] = base;
return process.nextTick(LOOP);
}
// stat & read the link if not read before
// call gotTarget as soon as the link target is known
var id = stat.dev.toString(32) + ':' + stat.ino.toString(32);
if (seenLinks[id]) {
return gotTarget(null, seenLinks[id], base);
}
fs.stat(base, function(err) {
if (err) return cb(err);
fs.readlink(base, function(err, target) {
gotTarget(err, seenLinks[id] = target);
});
});
}
function gotTarget(err, target, base) {
if (err) return cb(err);
var resolvedLink = pathModule.resolve(previous, target);
if (cache) cache[base] = resolvedLink;
gotResolvedLink(resolvedLink);
}
function gotResolvedLink(resolvedLink) {
// resolve the link, then start over
p = pathModule.resolve(resolvedLink, p.slice(pos));
pos = 0;
previous = base = current = '';
return process.nextTick(LOOP);
}
};
}
var pool;
function allocNewPool() {
pool = new Buffer(kPoolSize);
pool.used = 0;
}
fs.createReadStream = function(path, options) {
return new ReadStream(path, options);
};
var ReadStream = fs.ReadStream = function(path, options) {
if (!(this instanceof ReadStream)) return new ReadStream(path, options);
Stream.call(this);
var self = this;
this.path = path;
this.fd = null;
this.readable = true;
this.paused = false;
this.flags = 'r';
this.mode = 438; /*=0666*/
this.bufferSize = 64 * 1024;
options = options || {};
// Mixin options into this
var keys = Object.keys(options);
for (var index = 0, length = keys.length; index < length; index++) {
var key = keys[index];
this[key] = options[key];
}
if (this.encoding) this.setEncoding(this.encoding);
if (this.start !== undefined) {
if ('number' !== typeof this.start) {
throw TypeError('start must be a Number');
}
if (this.end === undefined) {
this.end = Infinity;
} else if ('number' !== typeof this.end) {
throw TypeError('end must be a Number');
}
if (this.start > this.end) {
throw new Error('start must be <= end');
}
this.pos = this.start;
}
if (this.fd !== null) {
this._read();
return;
}
fs.open(this.path, this.flags, this.mode, function(err, fd) {
if (err) {
self.emit('error', err);
self.readable = false;
return;
}
self.fd = fd;
self.emit('open', fd);
self._read();
});
};
util.inherits(ReadStream, Stream);
fs.FileReadStream = fs.ReadStream; // support the legacy name
ReadStream.prototype.setEncoding = function(encoding) {
var StringDecoder = require('string_decoder').StringDecoder; // lazy load
this._decoder = new StringDecoder(encoding);
};
ReadStream.prototype._read = function() {
var self = this;
if (!this.readable || this.paused || this.reading) return;
this.reading = true;
if (!pool || pool.length - pool.used < kMinPoolSpace) {
// discard the old pool. Can't add to the free list because
// users might have refernces to slices on it.
pool = null;
allocNewPool();
}
// Grab another reference to the pool in the case that while we're in the
// thread pool another read() finishes up the pool, and allocates a new
// one.
var thisPool = pool;
var toRead = Math.min(pool.length - pool.used, ~~this.bufferSize);
var start = pool.used;
if (this.pos !== undefined) {
toRead = Math.min(this.end - this.pos + 1, toRead);
}
function afterRead(err, bytesRead) {
self.reading = false;
if (err) {
self.emit('error', err);
self.readable = false;
return;
}
if (bytesRead === 0) {
self.emit('end');
self.destroy();
return;
}
var b = thisPool.slice(start, start + bytesRead);
// Possible optimizition here?
// Reclaim some bytes if bytesRead < toRead?
// Would need to ensure that pool === thisPool.
// do not emit events if the stream is paused
if (self.paused) {
self.buffer = b;
return;
}
// do not emit events anymore after we declared the stream unreadable
if (!self.readable) return;
self._emitData(b);
self._read();
}
fs.read(this.fd, pool, pool.used, toRead, this.pos, afterRead);
if (this.pos !== undefined) {
this.pos += toRead;
}
pool.used += toRead;
};
ReadStream.prototype._emitData = function(d) {
if (this._decoder) {
var string = this._decoder.write(d);
if (string.length) this.emit('data', string);
} else {
this.emit('data', d);
}
};
ReadStream.prototype.destroy = function(cb) {
var self = this;
this.readable = false;
function close() {
fs.close(self.fd, function(err) {
if (err) {
if (cb) cb(err);
self.emit('error', err);
return;
}
if (cb) cb(null);
self.emit('close');
});
}
if (this.fd) {
close();
} else {
this.addListener('open', close);
}
};
ReadStream.prototype.pause = function() {
this.paused = true;
};
ReadStream.prototype.resume = function() {
this.paused = false;
if (this.buffer) {
this._emitData(this.buffer);
this.buffer = null;
}
// hasn't opened yet.
if (null == this.fd) return;
this._read();
};
fs.createWriteStream = function(path, options) {
return new WriteStream(path, options);
};
var WriteStream = fs.WriteStream = function(path, options) {
if (!(this instanceof WriteStream)) return new WriteStream(path, options);
Stream.call(this);
this.path = path;
this.fd = null;
this.writable = true;
this.flags = 'w';
this.encoding = 'binary';
this.mode = 438; /*=0666*/
this.bytesWritten = 0;
options = options || {};
// Mixin options into this
var keys = Object.keys(options);
for (var index = 0, length = keys.length; index < length; index++) {
var key = keys[index];
this[key] = options[key];
}
if (this.start !== undefined) {
if ('number' !== typeof this.start) {
throw TypeError('start must be a Number');
}
if (this.start < 0) {
throw new Error('start must be >= zero');
}
this.pos = this.start;
}
this.busy = false;
this._queue = [];
if (this.fd === null) {
this._open = fs.open;
this._queue.push([this._open, this.path, this.flags, this.mode, undefined]);
this.flush();
}
};
util.inherits(WriteStream, Stream);
fs.FileWriteStream = fs.WriteStream; // support the legacy name
WriteStream.prototype.flush = function() {
if (this.busy) return;
var self = this;
var args = this._queue.shift();
if (!args) {
if (this.drainable) { this.emit('drain'); }
return;
}
this.busy = true;
var method = args.shift(),
cb = args.pop();
args.push(function(err) {
self.busy = false;
if (err) {
self.writable = false;
if (cb) {
cb(err);
}
self.emit('error', err);
return;
}
if (method == fs.write) {
self.bytesWritten += arguments[1];
if (cb) {
// write callback
cb(null, arguments[1]);
}
} else if (method === self._open) {
// save reference for file pointer
self.fd = arguments[1];
self.emit('open', self.fd);
} else if (method === fs.close) {
// stop flushing after close
if (cb) {
cb(null);
}
self.emit('close');
return;
}
self.flush();
});
// Inject the file pointer
if (method !== self._open) {
args.unshift(this.fd);
}
method.apply(this, args);
};
WriteStream.prototype.write = function(data) {
if (!this.writable) {
this.emit('error', new Error('stream not writable'));
return false;
}
this.drainable = true;
var cb;
if (typeof(arguments[arguments.length - 1]) == 'function') {
cb = arguments[arguments.length - 1];
}
if (!Buffer.isBuffer(data)) {
var encoding = 'utf8';
if (typeof(arguments[1]) == 'string') encoding = arguments[1];
data = new Buffer('' + data, encoding);
}
this._queue.push([fs.write, data, 0, data.length, this.pos, cb]);
if (this.pos !== undefined) {
this.pos += data.length;
}
this.flush();
return false;
};
WriteStream.prototype.end = function(data, encoding, cb) {
if (typeof(data) === 'function') {
cb = data;
} else if (typeof(encoding) === 'function') {
cb = encoding;
this.write(data);
} else if (arguments.length > 0) {
this.write(data, encoding);
}
this.writable = false;
this._queue.push([fs.close, cb]);
this.flush();
};
WriteStream.prototype.destroy = function(cb) {
var self = this;
this.writable = false;
function close() {
fs.close(self.fd, function(err) {
if (err) {
if (cb) { cb(err); }
self.emit('error', err);
return;
}
if (cb) { cb(null); }
self.emit('close');
});
}
if (this.fd) {
close();
} else {
this.addListener('open', close);
}
};
// There is no shutdown() for files.
WriteStream.prototype.destroySoon = WriteStream.prototype.end;
// SyncWriteStream is internal. DO NOT USE.
// Temporary hack for process.stdout and process.stderr when piped to files.
function SyncWriteStream(fd) {
this.fd = fd;
this.writable = true;
this.readable = false;
};
util.inherits(SyncWriteStream, Stream);
// Export
fs.SyncWriteStream = SyncWriteStream;
SyncWriteStream.prototype.write = function(data, arg1, arg2) {
var encoding, cb;
// parse arguments
if (arg1) {
if (typeof arg1 === 'string') {
encoding = arg1;
cb = arg2;
} else if (typeof arg1 === 'function') {
cb = arg1;
} else {
throw new Error("bad arg");
}
}
// Change strings to buffers. SLOW
if (typeof data == 'string') {
data = new Buffer(data, encoding);
}
fs.writeSync(this.fd, data, 0, data.length);
if (cb) {
process.nextTick(cb);
}
return true;
};
SyncWriteStream.prototype.end = function(data, arg1, arg2) {
if (data) {
this.write(data, arg1, arg2);
}
this.destroy();
};
SyncWriteStream.prototype.destroy = function() {
fs.closeSync(this.fd);
this.fd = null;
this.emit('close');
return true;
};
SyncWriteStream.prototype.destroySoon = SyncWriteStream.prototype.destroy;