| exports.debugLevel = 0; // Increase to get more verbose debug output |
| |
| function debugMessage (msg) { |
| if (exports.debugLevel > 0) { |
| node.error(__filename + ": " + msg.toString()); |
| } |
| } |
| |
| function debugObject (obj) { |
| if (exports.debugLevel > 0) { |
| node.error(__filename + ": " + JSON.stringify(obj)); |
| } |
| } |
| |
| exports.read = node.fs.cat; |
| |
| exports.write = function (filename, data, encoding) { |
| var promise = new node.Promise(); |
| |
| encoding = encoding || "utf8"; // default to utf8 |
| |
| node.fs.open(filename, node.O_WRONLY | node.O_TRUNC | node.O_CREAT, 0666) |
| .addCallback(function (fd) { |
| function doWrite (_data) { |
| node.fs.write(fd, _data, 0, encoding) |
| .addErrback(function () { |
| node.fs.close(fd); |
| }) |
| .addCallback(function (written) { |
| if (written == _data.length) { |
| node.fs.close(fd); |
| } else { |
| doWrite(_data.slice(written)); |
| } |
| }); |
| } |
| doWrite(data); |
| }) |
| .addErrback(function () { |
| promise.emitError() |
| }); |
| |
| return promise; |
| }; |
| |
| exports.File = function (filename, mode, options) { |
| var self = this; |
| |
| options = options || {}; |
| self.encoding = options.encoding || "utf8"; |
| |
| self.filename = filename; |
| |
| self.actionQueue = []; |
| self.currentAction = null; |
| |
| switch (mode) { |
| case "r": |
| self.flags = node.O_RDONLY; |
| break; |
| |
| case "r+": |
| self.flags = node.O_RDWR; |
| break; |
| |
| case "w": |
| self.flags = node.O_CREAT | node.O_TRUNC | node.O_WRONLY; |
| break; |
| |
| case "w+": |
| self.flags = node.O_CREAT | node.O_TRUNC | node.O_RDWR; |
| break; |
| |
| case "a": |
| self.flags = node.O_APPEND | node.O_CREAT | node.O_WRONLY; |
| break; |
| |
| case "a+": |
| self.flags = node.O_APPEND | node.O_CREAT | node.O_RDWR; |
| break; |
| |
| default: |
| throw new Error("Unknown mode"); |
| } |
| |
| self.open(self.filename, self.flags, 0666).addCallback(function (fd) { |
| debugMessage(self.filename + " opened. fd = " + fd); |
| self.fd = fd; |
| }).addErrback(function () { |
| self.emit("error", ["open"]); |
| }); |
| }; |
| |
| var proto = exports.File.prototype; |
| |
| proto._maybeDispatch = function () { |
| var self = this; |
| |
| if (self.currentAction) return; |
| self.currentAction = self.actionQueue.shift(); |
| if (!self.currentAction) return; |
| |
| debugObject(self.currentAction); |
| |
| var args = self.currentAction.args || []; |
| |
| if (self.currentAction.method != "open") { |
| args.unshift(self.fd); |
| } |
| |
| var method = self.currentAction.method; |
| |
| if (!args[3] && (method == "read" || method == "write")) { |
| args[3] = self.encoding; |
| } |
| |
| var promise = node.fs[method].apply(self, args); |
| |
| var userPromise = self.currentAction.promise; |
| |
| promise.addCallback(function () { |
| node.assert(self.currentAction.promise == userPromise); |
| userPromise.emitSuccess.apply(userPromise, arguments); |
| self.currentAction = null; |
| self._maybeDispatch(); |
| }).addErrback(function () { |
| debugMessage("Error in method " + method); |
| node.assert(self.currentAction.promise == userPromise); |
| userPromise.emitError.apply(userPromise, arguments); |
| self.currentAction = null; |
| self._maybeDispatch(); |
| }); |
| }; |
| |
| proto._queueAction = function (method, args) { |
| var userPromise = new node.Promise; |
| this.actionQueue.push({ method: method, args: args, promise: userPromise }); |
| this._maybeDispatch(); |
| return userPromise; |
| }; |
| |
| // FIXME the following can probably be DRY'd up with some fancy getter |
| // stuff. |
| |
| proto.open = function (filename, flags, mode) { |
| return this._queueAction("open", [filename, flags, mode]); |
| }; |
| |
| proto.write = function (data, pos, encoding) { |
| return this._queueAction("write", [data, pos, encoding]); |
| }; |
| |
| proto.read = function (length, pos, encoding) { |
| return this._queueAction("read", [length, pos, encoding]); |
| }; |
| |
| proto.close = function () { |
| return this._queueAction("close"); |
| }; |