| // 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. |
| // A bit simpler than readable streams. |
| // Implement an async ._write(chunk, encoding, cb), and it'll handle all |
| // the drain event emission and buffering. |
| 'use strict'; |
| |
| module.exports = Writable; |
| /* <replacement> */ |
| |
| function WriteReq(chunk, encoding, cb) { |
| this.chunk = chunk; |
| this.encoding = encoding; |
| this.callback = cb; |
| this.next = null; |
| } // It seems a linked list but it is not |
| // there will be only 2 of these for each stream |
| |
| |
| function CorkedRequest(state) { |
| var _this = this; |
| |
| this.next = null; |
| this.entry = null; |
| |
| this.finish = function () { |
| onCorkedFinish(_this, state); |
| }; |
| } |
| /* </replacement> */ |
| |
| /*<replacement>*/ |
| |
| |
| var Duplex; |
| /*</replacement>*/ |
| |
| Writable.WritableState = WritableState; |
| /*<replacement>*/ |
| |
| var internalUtil = { |
| deprecate: require('util-deprecate') |
| }; |
| /*</replacement>*/ |
| |
| /*<replacement>*/ |
| |
| var Stream = require('./internal/streams/stream'); |
| /*</replacement>*/ |
| |
| |
| var Buffer = require('buffer').Buffer; |
| |
| var OurUint8Array = global.Uint8Array || function () {}; |
| |
| function _uint8ArrayToBuffer(chunk) { |
| return Buffer.from(chunk); |
| } |
| |
| function _isUint8Array(obj) { |
| return Buffer.isBuffer(obj) || obj instanceof OurUint8Array; |
| } |
| |
| var destroyImpl = require('./internal/streams/destroy'); |
| |
| var _require = require('./internal/streams/state'), |
| getHighWaterMark = _require.getHighWaterMark; |
| |
| var _require$codes = require('../errors').codes, |
| ERR_INVALID_ARG_TYPE = _require$codes.ERR_INVALID_ARG_TYPE, |
| ERR_METHOD_NOT_IMPLEMENTED = _require$codes.ERR_METHOD_NOT_IMPLEMENTED, |
| ERR_MULTIPLE_CALLBACK = _require$codes.ERR_MULTIPLE_CALLBACK, |
| ERR_STREAM_CANNOT_PIPE = _require$codes.ERR_STREAM_CANNOT_PIPE, |
| ERR_STREAM_DESTROYED = _require$codes.ERR_STREAM_DESTROYED, |
| ERR_STREAM_NULL_VALUES = _require$codes.ERR_STREAM_NULL_VALUES, |
| ERR_STREAM_WRITE_AFTER_END = _require$codes.ERR_STREAM_WRITE_AFTER_END, |
| ERR_UNKNOWN_ENCODING = _require$codes.ERR_UNKNOWN_ENCODING; |
| |
| require('inherits')(Writable, Stream); |
| |
| function nop() {} |
| |
| function WritableState(options, stream, isDuplex) { |
| Duplex = Duplex || require('./_stream_duplex'); |
| options = options || {}; // Duplex streams are both readable and writable, but share |
| // the same options object. |
| // However, some cases require setting options to different |
| // values for the readable and the writable sides of the duplex stream, |
| // e.g. options.readableObjectMode vs. options.writableObjectMode, etc. |
| |
| if (typeof isDuplex !== 'boolean') isDuplex = stream instanceof Duplex; // object stream flag to indicate whether or not this stream |
| // contains buffers or objects. |
| |
| this.objectMode = !!options.objectMode; |
| if (isDuplex) this.objectMode = this.objectMode || !!options.writableObjectMode; // the point at which write() starts returning false |
| // Note: 0 is a valid value, means that we always return false if |
| // the entire buffer is not flushed immediately on write() |
| |
| this.highWaterMark = getHighWaterMark(this, options, 'writableHighWaterMark', isDuplex); // if _final has been called |
| |
| this.finalCalled = false; // drain event flag. |
| |
| this.needDrain = false; // at the start of calling end() |
| |
| this.ending = false; // when end() has been called, and returned |
| |
| this.ended = false; // when 'finish' is emitted |
| |
| this.finished = false; // has it been destroyed |
| |
| this.destroyed = false; // should we decode strings into buffers before passing to _write? |
| // this is here so that some node-core streams can optimize string |
| // handling at a lower level. |
| |
| var noDecode = options.decodeStrings === false; |
| this.decodeStrings = !noDecode; // Crypto is kind of old and crusty. Historically, its default string |
| // encoding is 'binary' so we have to make this configurable. |
| // Everything else in the universe uses 'utf8', though. |
| |
| this.defaultEncoding = options.defaultEncoding || 'utf8'; // not an actual buffer we keep track of, but a measurement |
| // of how much we're waiting to get pushed to some underlying |
| // socket or file. |
| |
| this.length = 0; // a flag to see when we're in the middle of a write. |
| |
| this.writing = false; // when true all writes will be buffered until .uncork() call |
| |
| this.corked = 0; // a flag to be able to tell if the onwrite cb is called immediately, |
| // or on a later tick. We set this to true at first, because any |
| // actions that shouldn't happen until "later" should generally also |
| // not happen before the first write call. |
| |
| this.sync = true; // a flag to know if we're processing previously buffered items, which |
| // may call the _write() callback in the same tick, so that we don't |
| // end up in an overlapped onwrite situation. |
| |
| this.bufferProcessing = false; // the callback that's passed to _write(chunk,cb) |
| |
| this.onwrite = function (er) { |
| onwrite(stream, er); |
| }; // the callback that the user supplies to write(chunk,encoding,cb) |
| |
| |
| this.writecb = null; // the amount that is being written when _write is called. |
| |
| this.writelen = 0; |
| this.bufferedRequest = null; |
| this.lastBufferedRequest = null; // number of pending user-supplied write callbacks |
| // this must be 0 before 'finish' can be emitted |
| |
| this.pendingcb = 0; // emit prefinish if the only thing we're waiting for is _write cbs |
| // This is relevant for synchronous Transform streams |
| |
| this.prefinished = false; // True if the error was already emitted and should not be thrown again |
| |
| this.errorEmitted = false; // Should close be emitted on destroy. Defaults to true. |
| |
| this.emitClose = options.emitClose !== false; // count buffered requests |
| |
| this.bufferedRequestCount = 0; // allocate the first CorkedRequest, there is always |
| // one allocated and free to use, and we maintain at most two |
| |
| this.corkedRequestsFree = new CorkedRequest(this); |
| } |
| |
| WritableState.prototype.getBuffer = function getBuffer() { |
| var current = this.bufferedRequest; |
| var out = []; |
| |
| while (current) { |
| out.push(current); |
| current = current.next; |
| } |
| |
| return out; |
| }; |
| |
| (function () { |
| try { |
| Object.defineProperty(WritableState.prototype, 'buffer', { |
| get: internalUtil.deprecate(function writableStateBufferGetter() { |
| return this.getBuffer(); |
| }, '_writableState.buffer is deprecated. Use _writableState.getBuffer ' + 'instead.', 'DEP0003') |
| }); |
| } catch (_) {} |
| })(); // Test _writableState for inheritance to account for Duplex streams, |
| // whose prototype chain only points to Readable. |
| |
| |
| var realHasInstance; |
| |
| if (typeof Symbol === 'function' && Symbol.hasInstance && typeof Function.prototype[Symbol.hasInstance] === 'function') { |
| realHasInstance = Function.prototype[Symbol.hasInstance]; |
| Object.defineProperty(Writable, Symbol.hasInstance, { |
| value: function value(object) { |
| if (realHasInstance.call(this, object)) return true; |
| if (this !== Writable) return false; |
| return object && object._writableState instanceof WritableState; |
| } |
| }); |
| } else { |
| realHasInstance = function realHasInstance(object) { |
| return object instanceof this; |
| }; |
| } |
| |
| function Writable(options) { |
| Duplex = Duplex || require('./_stream_duplex'); // Writable ctor is applied to Duplexes, too. |
| // `realHasInstance` is necessary because using plain `instanceof` |
| // would return false, as no `_writableState` property is attached. |
| // Trying to use the custom `instanceof` for Writable here will also break the |
| // Node.js LazyTransform implementation, which has a non-trivial getter for |
| // `_writableState` that would lead to infinite recursion. |
| // Checking for a Stream.Duplex instance is faster here instead of inside |
| // the WritableState constructor, at least with V8 6.5 |
| |
| var isDuplex = this instanceof Duplex; |
| if (!isDuplex && !realHasInstance.call(Writable, this)) return new Writable(options); |
| this._writableState = new WritableState(options, this, isDuplex); // legacy. |
| |
| this.writable = true; |
| |
| if (options) { |
| if (typeof options.write === 'function') this._write = options.write; |
| if (typeof options.writev === 'function') this._writev = options.writev; |
| if (typeof options.destroy === 'function') this._destroy = options.destroy; |
| if (typeof options.final === 'function') this._final = options.final; |
| } |
| |
| Stream.call(this); |
| } // Otherwise people can pipe Writable streams, which is just wrong. |
| |
| |
| Writable.prototype.pipe = function () { |
| this.emit('error', new ERR_STREAM_CANNOT_PIPE()); |
| }; |
| |
| function writeAfterEnd(stream, cb) { |
| var er = new ERR_STREAM_WRITE_AFTER_END(); // TODO: defer error events consistently everywhere, not just the cb |
| |
| stream.emit('error', er); |
| process.nextTick(cb, er); |
| } // Checks that a user-supplied chunk is valid, especially for the particular |
| // mode the stream is in. Currently this means that `null` is never accepted |
| // and undefined/non-string values are only allowed in object mode. |
| |
| |
| function validChunk(stream, state, chunk, cb) { |
| var er; |
| |
| if (chunk === null) { |
| er = new ERR_STREAM_NULL_VALUES(); |
| } else if (typeof chunk !== 'string' && !state.objectMode) { |
| er = new ERR_INVALID_ARG_TYPE('chunk', ['string', 'Buffer'], chunk); |
| } |
| |
| if (er) { |
| stream.emit('error', er); |
| process.nextTick(cb, er); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| Writable.prototype.write = function (chunk, encoding, cb) { |
| var state = this._writableState; |
| var ret = false; |
| |
| var isBuf = !state.objectMode && _isUint8Array(chunk); |
| |
| if (isBuf && !Buffer.isBuffer(chunk)) { |
| chunk = _uint8ArrayToBuffer(chunk); |
| } |
| |
| if (typeof encoding === 'function') { |
| cb = encoding; |
| encoding = null; |
| } |
| |
| if (isBuf) encoding = 'buffer';else if (!encoding) encoding = state.defaultEncoding; |
| if (typeof cb !== 'function') cb = nop; |
| if (state.ending) writeAfterEnd(this, cb);else if (isBuf || validChunk(this, state, chunk, cb)) { |
| state.pendingcb++; |
| ret = writeOrBuffer(this, state, isBuf, chunk, encoding, cb); |
| } |
| return ret; |
| }; |
| |
| Writable.prototype.cork = function () { |
| this._writableState.corked++; |
| }; |
| |
| Writable.prototype.uncork = function () { |
| var state = this._writableState; |
| |
| if (state.corked) { |
| state.corked--; |
| if (!state.writing && !state.corked && !state.bufferProcessing && state.bufferedRequest) clearBuffer(this, state); |
| } |
| }; |
| |
| Writable.prototype.setDefaultEncoding = function setDefaultEncoding(encoding) { |
| // node::ParseEncoding() requires lower case. |
| if (typeof encoding === 'string') encoding = encoding.toLowerCase(); |
| if (!(['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', 'raw'].indexOf((encoding + '').toLowerCase()) > -1)) throw new ERR_UNKNOWN_ENCODING(encoding); |
| this._writableState.defaultEncoding = encoding; |
| return this; |
| }; |
| |
| Object.defineProperty(Writable.prototype, 'writableBuffer', { |
| // making it explicit this property is not enumerable |
| // because otherwise some prototype manipulation in |
| // userland will fail |
| enumerable: false, |
| get: function get() { |
| return this._writableState && this._writableState.getBuffer(); |
| } |
| }); |
| |
| function decodeChunk(state, chunk, encoding) { |
| if (!state.objectMode && state.decodeStrings !== false && typeof chunk === 'string') { |
| chunk = Buffer.from(chunk, encoding); |
| } |
| |
| return chunk; |
| } |
| |
| Object.defineProperty(Writable.prototype, 'writableHighWaterMark', { |
| // making it explicit this property is not enumerable |
| // because otherwise some prototype manipulation in |
| // userland will fail |
| enumerable: false, |
| get: function get() { |
| return this._writableState.highWaterMark; |
| } |
| }); // if we're already writing something, then just put this |
| // in the queue, and wait our turn. Otherwise, call _write |
| // If we return false, then we need a drain event, so set that flag. |
| |
| function writeOrBuffer(stream, state, isBuf, chunk, encoding, cb) { |
| if (!isBuf) { |
| var newChunk = decodeChunk(state, chunk, encoding); |
| |
| if (chunk !== newChunk) { |
| isBuf = true; |
| encoding = 'buffer'; |
| chunk = newChunk; |
| } |
| } |
| |
| var len = state.objectMode ? 1 : chunk.length; |
| state.length += len; |
| var ret = state.length < state.highWaterMark; // we must ensure that previous needDrain will not be reset to false. |
| |
| if (!ret) state.needDrain = true; |
| |
| if (state.writing || state.corked) { |
| var last = state.lastBufferedRequest; |
| state.lastBufferedRequest = { |
| chunk: chunk, |
| encoding: encoding, |
| isBuf: isBuf, |
| callback: cb, |
| next: null |
| }; |
| |
| if (last) { |
| last.next = state.lastBufferedRequest; |
| } else { |
| state.bufferedRequest = state.lastBufferedRequest; |
| } |
| |
| state.bufferedRequestCount += 1; |
| } else { |
| doWrite(stream, state, false, len, chunk, encoding, cb); |
| } |
| |
| return ret; |
| } |
| |
| function doWrite(stream, state, writev, len, chunk, encoding, cb) { |
| state.writelen = len; |
| state.writecb = cb; |
| state.writing = true; |
| state.sync = true; |
| if (state.destroyed) state.onwrite(new ERR_STREAM_DESTROYED('write'));else if (writev) stream._writev(chunk, state.onwrite);else stream._write(chunk, encoding, state.onwrite); |
| state.sync = false; |
| } |
| |
| function onwriteError(stream, state, sync, er, cb) { |
| --state.pendingcb; |
| |
| if (sync) { |
| // defer the callback if we are being called synchronously |
| // to avoid piling up things on the stack |
| process.nextTick(cb, er); // this can emit finish, and it will always happen |
| // after error |
| |
| process.nextTick(finishMaybe, stream, state); |
| stream._writableState.errorEmitted = true; |
| stream.emit('error', er); |
| } else { |
| // the caller expect this to happen before if |
| // it is async |
| cb(er); |
| stream._writableState.errorEmitted = true; |
| stream.emit('error', er); // this can emit finish, but finish must |
| // always follow error |
| |
| finishMaybe(stream, state); |
| } |
| } |
| |
| function onwriteStateUpdate(state) { |
| state.writing = false; |
| state.writecb = null; |
| state.length -= state.writelen; |
| state.writelen = 0; |
| } |
| |
| function onwrite(stream, er) { |
| var state = stream._writableState; |
| var sync = state.sync; |
| var cb = state.writecb; |
| if (typeof cb !== 'function') throw new ERR_MULTIPLE_CALLBACK(); |
| onwriteStateUpdate(state); |
| if (er) onwriteError(stream, state, sync, er, cb);else { |
| // Check if we're actually ready to finish, but don't emit yet |
| var finished = needFinish(state) || stream.destroyed; |
| |
| if (!finished && !state.corked && !state.bufferProcessing && state.bufferedRequest) { |
| clearBuffer(stream, state); |
| } |
| |
| if (sync) { |
| process.nextTick(afterWrite, stream, state, finished, cb); |
| } else { |
| afterWrite(stream, state, finished, cb); |
| } |
| } |
| } |
| |
| function afterWrite(stream, state, finished, cb) { |
| if (!finished) onwriteDrain(stream, state); |
| state.pendingcb--; |
| cb(); |
| finishMaybe(stream, state); |
| } // Must force callback to be called on nextTick, so that we don't |
| // emit 'drain' before the write() consumer gets the 'false' return |
| // value, and has a chance to attach a 'drain' listener. |
| |
| |
| function onwriteDrain(stream, state) { |
| if (state.length === 0 && state.needDrain) { |
| state.needDrain = false; |
| stream.emit('drain'); |
| } |
| } // if there's something in the buffer waiting, then process it |
| |
| |
| function clearBuffer(stream, state) { |
| state.bufferProcessing = true; |
| var entry = state.bufferedRequest; |
| |
| if (stream._writev && entry && entry.next) { |
| // Fast case, write everything using _writev() |
| var l = state.bufferedRequestCount; |
| var buffer = new Array(l); |
| var holder = state.corkedRequestsFree; |
| holder.entry = entry; |
| var count = 0; |
| var allBuffers = true; |
| |
| while (entry) { |
| buffer[count] = entry; |
| if (!entry.isBuf) allBuffers = false; |
| entry = entry.next; |
| count += 1; |
| } |
| |
| buffer.allBuffers = allBuffers; |
| doWrite(stream, state, true, state.length, buffer, '', holder.finish); // doWrite is almost always async, defer these to save a bit of time |
| // as the hot path ends with doWrite |
| |
| state.pendingcb++; |
| state.lastBufferedRequest = null; |
| |
| if (holder.next) { |
| state.corkedRequestsFree = holder.next; |
| holder.next = null; |
| } else { |
| state.corkedRequestsFree = new CorkedRequest(state); |
| } |
| |
| state.bufferedRequestCount = 0; |
| } else { |
| // Slow case, write chunks one-by-one |
| while (entry) { |
| var chunk = entry.chunk; |
| var encoding = entry.encoding; |
| var cb = entry.callback; |
| var len = state.objectMode ? 1 : chunk.length; |
| doWrite(stream, state, false, len, chunk, encoding, cb); |
| entry = entry.next; |
| state.bufferedRequestCount--; // if we didn't call the onwrite immediately, then |
| // it means that we need to wait until it does. |
| // also, that means that the chunk and cb are currently |
| // being processed, so move the buffer counter past them. |
| |
| if (state.writing) { |
| break; |
| } |
| } |
| |
| if (entry === null) state.lastBufferedRequest = null; |
| } |
| |
| state.bufferedRequest = entry; |
| state.bufferProcessing = false; |
| } |
| |
| Writable.prototype._write = function (chunk, encoding, cb) { |
| cb(new ERR_METHOD_NOT_IMPLEMENTED('_write()')); |
| }; |
| |
| Writable.prototype._writev = null; |
| |
| Writable.prototype.end = function (chunk, encoding, cb) { |
| var state = this._writableState; |
| |
| if (typeof chunk === 'function') { |
| cb = chunk; |
| chunk = null; |
| encoding = null; |
| } else if (typeof encoding === 'function') { |
| cb = encoding; |
| encoding = null; |
| } |
| |
| if (chunk !== null && chunk !== undefined) this.write(chunk, encoding); // .end() fully uncorks |
| |
| if (state.corked) { |
| state.corked = 1; |
| this.uncork(); |
| } // ignore unnecessary end() calls. |
| |
| |
| if (!state.ending) endWritable(this, state, cb); |
| return this; |
| }; |
| |
| Object.defineProperty(Writable.prototype, 'writableLength', { |
| // making it explicit this property is not enumerable |
| // because otherwise some prototype manipulation in |
| // userland will fail |
| enumerable: false, |
| get: function get() { |
| return this._writableState.length; |
| } |
| }); |
| |
| function needFinish(state) { |
| return state.ending && state.length === 0 && state.bufferedRequest === null && !state.finished && !state.writing; |
| } |
| |
| function callFinal(stream, state) { |
| stream._final(function (err) { |
| state.pendingcb--; |
| |
| if (err) { |
| stream.emit('error', err); |
| } |
| |
| state.prefinished = true; |
| stream.emit('prefinish'); |
| finishMaybe(stream, state); |
| }); |
| } |
| |
| function prefinish(stream, state) { |
| if (!state.prefinished && !state.finalCalled) { |
| if (typeof stream._final === 'function' && !state.destroyed) { |
| state.pendingcb++; |
| state.finalCalled = true; |
| process.nextTick(callFinal, stream, state); |
| } else { |
| state.prefinished = true; |
| stream.emit('prefinish'); |
| } |
| } |
| } |
| |
| function finishMaybe(stream, state) { |
| var need = needFinish(state); |
| |
| if (need) { |
| prefinish(stream, state); |
| |
| if (state.pendingcb === 0) { |
| state.finished = true; |
| stream.emit('finish'); |
| } |
| } |
| |
| return need; |
| } |
| |
| function endWritable(stream, state, cb) { |
| state.ending = true; |
| finishMaybe(stream, state); |
| |
| if (cb) { |
| if (state.finished) process.nextTick(cb);else stream.once('finish', cb); |
| } |
| |
| state.ended = true; |
| stream.writable = false; |
| } |
| |
| function onCorkedFinish(corkReq, state, err) { |
| var entry = corkReq.entry; |
| corkReq.entry = null; |
| |
| while (entry) { |
| var cb = entry.callback; |
| state.pendingcb--; |
| cb(err); |
| entry = entry.next; |
| } // reuse the free corkReq. |
| |
| |
| state.corkedRequestsFree.next = corkReq; |
| } |
| |
| Object.defineProperty(Writable.prototype, 'destroyed', { |
| // making it explicit this property is not enumerable |
| // because otherwise some prototype manipulation in |
| // userland will fail |
| enumerable: false, |
| get: function get() { |
| if (this._writableState === undefined) { |
| return false; |
| } |
| |
| return this._writableState.destroyed; |
| }, |
| set: function set(value) { |
| // we ignore the value if the stream |
| // has not been initialized yet |
| if (!this._writableState) { |
| return; |
| } // backward compatibility, the user is explicitly |
| // managing destroyed |
| |
| |
| this._writableState.destroyed = value; |
| } |
| }); |
| Writable.prototype.destroy = destroyImpl.destroy; |
| Writable.prototype._undestroy = destroyImpl.undestroy; |
| |
| Writable.prototype._destroy = function (err, cb) { |
| cb(err); |
| }; |