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					697 lines
				
				21 KiB
			| 
											3 years ago
										 | // 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; | ||
|  | 
 | ||
|  | var errorOrDestroy = destroyImpl.errorOrDestroy; | ||
|  | 
 | ||
|  | 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; // Should .destroy() be called after 'finish' (and potentially 'end')
 | ||
|  | 
 | ||
|  |   this.autoDestroy = !!options.autoDestroy; // 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 () { | ||
|  |   errorOrDestroy(this, 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
 | ||
|  | 
 | ||
|  |   errorOrDestroy(stream, 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) { | ||
|  |     errorOrDestroy(stream, 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; | ||
|  |     errorOrDestroy(stream, er); | ||
|  |   } else { | ||
|  |     // the caller expect this to happen before if
 | ||
|  |     // it is async
 | ||
|  |     cb(er); | ||
|  |     stream._writableState.errorEmitted = true; | ||
|  |     errorOrDestroy(stream, 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) { | ||
|  |       errorOrDestroy(stream, 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'); | ||
|  | 
 | ||
|  |       if (state.autoDestroy) { | ||
|  |         // In case of duplex streams we need a way to detect
 | ||
|  |         // if the readable side is ready for autoDestroy as well
 | ||
|  |         var rState = stream._readableState; | ||
|  | 
 | ||
|  |         if (!rState || rState.autoDestroy && rState.endEmitted) { | ||
|  |           stream.destroy(); | ||
|  |         } | ||
|  |       } | ||
|  |     } | ||
|  |   } | ||
|  | 
 | ||
|  |   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); | ||
|  | }; |