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nodejs/lib/fs.js
Felix Geisendörfer 55e964ec19 Fix: fs.readFile would execute callbacks twice
fs.readFile was executing a callback in a try..catch context, which is
a problem in itself. To make matters worse, it would re-execute the
same callback if there was an execution.

This patch fixes both of these problems.
2010-06-03 09:40:40 -07:00

940 lines
22 KiB
JavaScript

var sys = require('sys');
var events = require('events');
var Buffer = require('buffer').Buffer;
var binding = process.binding('fs');
var fs = exports;
var kMinPoolSpace = 128;
var kPoolSize = 40*1024;
fs.Stats = binding.Stats;
fs.Stats.prototype._checkModeProperty = function (property) {
return ((this.mode & property) === property);
};
fs.Stats.prototype.isDirectory = function () {
return this._checkModeProperty(process.S_IFDIR);
};
fs.Stats.prototype.isFile = function () {
return this._checkModeProperty(process.S_IFREG);
};
fs.Stats.prototype.isBlockDevice = function () {
return this._checkModeProperty(process.S_IFBLK);
};
fs.Stats.prototype.isCharacterDevice = function () {
return this._checkModeProperty(process.S_IFCHR);
};
fs.Stats.prototype.isSymbolicLink = function () {
return this._checkModeProperty(process.S_IFLNK);
};
fs.Stats.prototype.isFIFO = function () {
return this._checkModeProperty(process.S_IFIFO);
};
fs.Stats.prototype.isSocket = function () {
return this._checkModeProperty(process.S_IFSOCK);
};
fs.readFile = function (path, encoding_, callback) {
var encoding = typeof(encoding_) == 'string' ? encoding_ : null;
var callback_ = arguments[arguments.length - 1];
var callback = (typeof(callback_) == 'function' ? callback_ : noop);
binding.stat(path, function (err, stat) {
if (err) { callback(err); return; }
binding.open(path, process.O_RDONLY, 0666, function (err, fd) {
if (err) { callback(err); return; }
var size = stat.size;
var buffer = new Buffer(size);
var offset = 0;
function doRead() {
if (size < 1) {
callback(null, buffer);
return;
}
// position is offset or null so we can read files on unseekable mediums
binding.read(fd, buffer, offset, size - offset, offset || null, function (err, amount) {
if (err) {
callback(err);
binding.close(fd);
return;
}
if (amount + offset < size) {
offset += amount;
doRead();
return;
}
binding.close(fd);
if (encoding) {
try {
var str = buffer.toString(encoding);
} catch (err) {
callback(err);
return;
}
callback(null, str);
} else {
callback(null, buffer);
}
});
}
doRead();
});
});
};
fs.readFileSync = function (path, encoding) {
var fd = fs.openSync(path, process.O_RDONLY, 0666);
var stat = fs.statSync(path);
var buffer = new Buffer(stat.size);
var nread = 0;
while (nread < buffer.length) {
nread += fs.readSync(fd, buffer, nread, buffer.length - nread, null);
}
fs.closeSync(fd);
if (encoding) {
return buffer.toString(encoding);
} else {
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 process.O_RDONLY;
case "r+": return process.O_RDWR;
case "w": return process.O_CREAT | process.O_TRUNC | process.O_WRONLY;
case "w+": return process.O_CREAT | process.O_TRUNC | process.O_RDWR;
case "a": return process.O_APPEND | process.O_CREAT | process.O_WRONLY;
case "a+": return process.O_APPEND | process.O_CREAT | process.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);
};
fs.open = function (path, flags, mode, callback) {
if (mode === undefined) { mode = 0666; }
binding.open(path, stringToFlags(flags), mode, callback || noop);
};
fs.openSync = function (path, flags, mode) {
if (mode === undefined) { mode = 0666; }
return binding.open(path, stringToFlags(flags), mode);
};
fs.read = function (fd, buffer, offset, length, position, callback) {
if (!(buffer instanceof 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);
};
}
binding.read(fd, buffer, offset, length, position, callback || noop);
};
fs.readSync = function (fd, buffer, offset, length, position) {
var legacy = false;
if (!(buffer instanceof Buffer)) {
// legacy string interface (fd, length, position, encoding, callback)
legacy = true;
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 instanceof 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;
}
binding.write(fd, buffer, offset, length, position, callback || noop);
};
fs.writeSync = function (fd, buffer, offset, length, position) {
if (!(buffer instanceof Buffer)) {
// legacy string interface (fd, data, position, encoding)
position = arguments[2];
buffer = new Buffer(''+arguments[1], arguments[3]);
offset = 0;
length = buffer.length;
}
binding.write(fd, buffer, offset, length, position);
};
fs.rename = function (oldPath, newPath, callback) {
binding.rename(oldPath, newPath, callback || noop);
};
fs.renameSync = function (oldPath, newPath) {
return binding.rename(oldPath, 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(path, callback || noop);
};
fs.rmdirSync = function (path) {
return binding.rmdir(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) {
binding.mkdir(path, mode, callback || noop);
};
fs.mkdirSync = function (path, mode) {
return binding.mkdir(path, mode);
};
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(path, callback || noop);
};
fs.readdirSync = function (path) {
return binding.readdir(path);
};
fs.fstat = function (fd, callback) {
binding.fstat(fd, callback || noop);
};
fs.lstat = function (path, callback) {
binding.lstat(path, callback || noop);
};
fs.stat = function (path, callback) {
binding.stat(path, callback || noop);
};
fs.fstatSync = function (fd) {
return binding.fstat(fd);
};
fs.lstatSync = function (path) {
return binding.lstat(path);
};
fs.statSync = function (path) {
return binding.stat(path);
};
fs.readlink = function (path, callback) {
binding.readlink(path, callback || noop);
};
fs.readlinkSync = function (path) {
return binding.readlink(path);
};
fs.symlink = function (destination, path, callback) {
binding.symlink(destination, path, callback || noop);
};
fs.symlinkSync = function (destination, path) {
return binding.symlink(destination, path);
};
fs.link = function (srcpath, dstpath, callback) {
binding.link(srcpath, dstpath, callback || noop);
};
fs.linkSync = function (srcpath, dstpath) {
return binding.link(srcpath, dstpath);
};
fs.unlink = function (path, callback) {
binding.unlink(path, callback || noop);
};
fs.unlinkSync = function (path) {
return binding.unlink(path);
};
fs.chmod = function (path, mode, callback) {
binding.chmod(path, mode, callback || noop);
};
fs.chmodSync = function (path, mode) {
return binding.chmod(path, mode);
};
fs.chown = function(path, uid, gid, callback) {
binding.chown(path, uid, gid, callback || noop);
};
fs.chownSync = function(path, uid, gid) {
return binding.chown(path, uid, gid);
};
function writeAll (fd, data, encoding, callback) {
fs.write(fd, data, 0, encoding, function (writeErr, written) {
if (writeErr) {
fs.close(fd, function () {
if (callback) callback(writeErr);
});
} else {
if (written === data.length) {
fs.close(fd, callback);
} else {
writeAll(fd, data.slice(written), encoding, callback);
}
}
});
}
fs.writeFile = function (path, data, encoding_, callback) {
var encoding = (typeof(encoding_) == 'string' ? encoding_ : 'utf8');
var callback_ = arguments[arguments.length - 1];
var callback = (typeof(callback_) == 'function' ? callback_ : null);
fs.open(path, 'w', 0666, function (openErr, fd) {
if (openErr) {
if (callback) callback(openErr);
} else {
writeAll(fd, data, encoding, callback);
}
});
};
fs.writeFileSync = function (path, data, encoding) {
encoding = encoding || "utf8"; // default to utf8
var fd = fs.openSync(path, "w");
var written = 0;
while (written < data.length) {
written += fs.writeSync(fd, data, 0, encoding);
data = data.slice(written);
}
fs.closeSync(fd);
};
fs.cat = function () {
throw new Error("fs.cat is deprecated. Please use fs.readFile instead.");
};
fs.catSync = function () {
throw new Error("fs.catSync is deprecated. Please use fs.readFileSync instead.");
};
// Stat Change Watchers
var statWatchers = {};
fs.watchFile = function (filename) {
var stat;
var options;
var listener;
if ("object" == typeof arguments[1]) {
options = arguments[1];
listener = arguments[2];
} else {
options = {};
listener = arguments[1];
}
if (options.persistent === undefined) options.persistent = true;
if (options.interval === undefined) options.interval = 0;
if (statWatchers[filename]) {
stat = statWatchers[filename];
} else {
statWatchers[filename] = new binding.StatWatcher();
stat = statWatchers[filename];
stat.start(filename, options.persistent, options.interval);
}
stat.addListener("change", listener);
return stat;
};
fs.unwatchFile = function (filename) {
if (statWatchers[filename]) {
stat = statWatchers[filename];
stat.stop();
statWatchers[filename] = undefined;
}
};
// Realpath
var path = require('path');
var normalize = path.normalize;
var normalizeArray = path.normalizeArray;
fs.realpathSync = function (path) {
var seen_links = {}, knownHards = {}, buf, i = 0, part, x, stats;
if (path.charAt(0) !== '/') {
var cwd = process.cwd().split('/');
path = cwd.concat(path.split('/'));
path = normalizeArray(path);
i = cwd.length;
buf = [].concat(cwd);
} else {
path = normalizeArray(path.split('/'));
buf = [''];
}
for (; i<path.length; i++) {
part = path.slice(0, i+1).join('/');
if (part.length !== 0) {
if (part in knownHards) {
buf.push(path[i]);
} else {
stats = fs.lstatSync(part);
if (stats.isSymbolicLink()) {
x = stats.dev.toString(32)+":"+stats.ino.toString(32);
if (x in seen_links)
throw new Error("cyclic link at "+part);
seen_links[x] = true;
part = fs.readlinkSync(part);
if (part.charAt(0) === '/') {
// absolute
path = normalizeArray(part.split('/'));
buf = [''];
i = 0;
} else {
// relative
Array.prototype.splice.apply(path, [i, 1].concat(part.split('/')));
part = normalizeArray(path);
var y = 0, L = Math.max(path.length, part.length), delta;
for (; y<L && path[y] === part[y]; y++);
if (y !== L) {
path = part;
delta = i-y;
i = y-1;
if (delta > 0) buf.splice(y, delta);
} else {
i--;
}
}
} else {
buf.push(path[i]);
knownHards[buf.join('/')] = true;
}
}
}
}
return buf.join('/');
}
fs.realpath = function (path, callback) {
var seen_links = {}, knownHards = {}, buf = [''], i = 0, part, x;
if (path.charAt(0) !== '/') {
// assumes cwd is canonical
var cwd = process.cwd().split('/');
path = cwd.concat(path.split('/'));
path = normalizeArray(path);
i = cwd.length-1;
buf = [].concat(cwd);
} else {
path = normalizeArray(path.split('/'));
}
function done(err) {
if (callback) {
if (!err) callback(err, buf.join('/'));
else callback(err);
}
}
function next() {
if (++i === path.length) return done();
part = path.slice(0, i+1).join('/');
if (part.length === 0) return next();
if (part in knownHards) {
buf.push(path[i]);
next();
} else {
fs.lstat(part, function(err, stats){
if (err) return done(err);
if (stats.isSymbolicLink()) {
x = stats.dev.toString(32)+":"+stats.ino.toString(32);
if (x in seen_links)
return done(new Error("cyclic link at "+part));
seen_links[x] = true;
fs.readlink(part, function(err, npart){
if (err) return done(err);
part = npart;
if (part.charAt(0) === '/') {
// absolute
path = normalizeArray(part.split('/'));
buf = [''];
i = 0;
} else {
// relative
Array.prototype.splice.apply(path, [i, 1].concat(part.split('/')));
part = normalizeArray(path);
var y = 0, L = Math.max(path.length, part.length), delta;
for (; y<L && path[y] === part[y]; y++);
if (y !== L) {
path = part;
delta = i-y;
i = y-1; // resolve new node if needed
if (delta > 0) buf.splice(y, delta);
}
else {
i--; // resolve new node if needed
}
}
next();
}); // binding.readlink
}
else {
buf.push(path[i]);
knownHards[buf.join('/')] = true;
next();
}
}); // binding.lstat
}
}
next();
};
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) {
events.EventEmitter.call(this);
this.path = path;
this.fd = null;
this.readable = true;
this.paused = false;
this.flags = 'r';
this.mode = 0666;
this.bufferSize = 4 * 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.fd !== null) {
return;
}
var self = this;
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();
});
};
sys.inherits(ReadStream, events.EventEmitter);
fs.FileReadStream = fs.ReadStream; // support the legacy name
ReadStream.prototype.setEncoding = function (encoding) {
var Utf8Decoder = require("utf8decoder").Utf8Decoder; // lazy load
var self = this;
this._encoding = encoding.toLowerCase();
if (this._encoding == 'utf-8' || this._encoding == 'utf8') {
this._decoder = new Utf8Decoder();
this._decoder.onString = function(str) {
self.emit('data', str);
};
} else if (this._decoder) {
delete this._decoder;
}
};
ReadStream.prototype._read = function () {
var self = this;
if (!self.readable || self.paused) return;
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;
function afterRead (err, bytesRead) {
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(self.fd, pool, pool.used, toRead, undefined, afterRead);
pool.used += toRead;
};
ReadStream.prototype._emitData = function (d) {
if (!this._encoding) {
this.emit('data', d);
} else if (this._decoder) {
this._decoder.write(d);
} else {
var string = d.toString(this._encoding, 0, d.length);
this.emit('data', string);
}
};
var readStreamForceCloseWarning;
ReadStream.prototype.forceClose = function (cb) {
if (!readStreamForceCloseWarning) {
readStreamForceCloseWarning = "ReadStream.prototype.forceClose renamed to destroy()";
sys.error(readStreamForceCloseWarning);
}
return this.destroy(cb);
};
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;
}
this._read();
};
fs.createWriteStream = function(path, options) {
return new WriteStream(path, options);
};
var WriteStream = fs.WriteStream = function(path, options) {
events.EventEmitter.call(this);
this.path = path;
this.fd = null;
this.writeable = true;
this.flags = 'w';
this.encoding = 'binary';
this.mode = 0666;
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];
}
this.busy = false;
this._queue = [];
if (this.fd === null) {
this._queue.push([fs.open, this.path, this.flags, this.mode, undefined]);
this.flush();
}
};
sys.inherits(WriteStream, events.EventEmitter);
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) return self.emit('drain');
this.busy = true;
var method = args.shift(),
cb = args.pop();
var self = this;
args.push(function(err) {
self.busy = false;
if (err) {
self.writeable = false;
if (cb) {
cb(err);
}
self.emit('error', err);
return;
}
// stop flushing after close
if (method === fs.close) {
if (cb) {
cb(null);
}
self.emit('close');
return;
}
// save reference for file pointer
if (method === fs.open) {
self.fd = arguments[1];
self.emit('open', self.fd);
} else if (cb) {
// write callback
cb(null, arguments[1]);
}
self.flush();
});
// Inject the file pointer
if (method !== fs.open) {
args.unshift(self.fd);
}
method.apply(this, args);
};
WriteStream.prototype.write = function (data) {
if (!this.writeable) {
throw new Error('stream not writeable');
}
var cb;
if (typeof(arguments[arguments.length-1]) == 'function') {
cb = arguments[arguments.length-1];
}
if (data instanceof Buffer) {
this._queue.push([fs.write, data, 0, data.length, null, cb]);
} else {
var encoding = 'utf8';
if (typeof(arguments[1]) == 'string') encoding = arguments[1];
this._queue.push([fs.write, data, undefined, encoding, cb]);
}
this.flush();
return false;
};
var writeStreamCloseWarning;
WriteStream.prototype.close = function (cb) {
if (!writeStreamCloseWarning) {
writeStreamCloseWarning = "WriteStream.prototype.close renamed to end()";
sys.error(writeStreamCloseWarning);
}
return this.end(cb);
}
WriteStream.prototype.end = function (cb) {
this.writeable = false;
this._queue.push([fs.close, cb]);
this.flush();
};
var writeStreamForceCloseWarning;
WriteStream.prototype.forceClose = function (cb) {
if (!writeStreamForceCloseWarning) {
writeStreamForceCloseWarning = "WriteStream.prototype.forceClose renamed to destroy()";
sys.error(writeStreamForceCloseWarning);
}
return this.destroy(cb);
};
WriteStream.prototype.forceClose = function (cb) {
this.writeable = false;
fs.close(self.fd, function(err) {
if (err) {
if (cb) {
cb(err);
}
self.emit('error', err);
return;
}
if (cb) {
cb(null);
}
self.emit('close');
});
};