diff options
Diffstat (limited to 'deps/node/deps/npm/node_modules/duplexify/node_modules/readable-stream/lib/_stream_readable.js')
| -rw-r--r-- | deps/node/deps/npm/node_modules/duplexify/node_modules/readable-stream/lib/_stream_readable.js | 1019 |
1 files changed, 0 insertions, 1019 deletions
diff --git a/deps/node/deps/npm/node_modules/duplexify/node_modules/readable-stream/lib/_stream_readable.js b/deps/node/deps/npm/node_modules/duplexify/node_modules/readable-stream/lib/_stream_readable.js deleted file mode 100644 index bf34ac65..00000000 --- a/deps/node/deps/npm/node_modules/duplexify/node_modules/readable-stream/lib/_stream_readable.js +++ /dev/null @@ -1,1019 +0,0 @@ -// 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. - -'use strict'; - -/*<replacement>*/ - -var pna = require('process-nextick-args'); -/*</replacement>*/ - -module.exports = Readable; - -/*<replacement>*/ -var isArray = require('isarray'); -/*</replacement>*/ - -/*<replacement>*/ -var Duplex; -/*</replacement>*/ - -Readable.ReadableState = ReadableState; - -/*<replacement>*/ -var EE = require('events').EventEmitter; - -var EElistenerCount = function (emitter, type) { - return emitter.listeners(type).length; -}; -/*</replacement>*/ - -/*<replacement>*/ -var Stream = require('./internal/streams/stream'); -/*</replacement>*/ - -/*<replacement>*/ - -var Buffer = require('safe-buffer').Buffer; -var OurUint8Array = global.Uint8Array || function () {}; -function _uint8ArrayToBuffer(chunk) { - return Buffer.from(chunk); -} -function _isUint8Array(obj) { - return Buffer.isBuffer(obj) || obj instanceof OurUint8Array; -} - -/*</replacement>*/ - -/*<replacement>*/ -var util = require('core-util-is'); -util.inherits = require('inherits'); -/*</replacement>*/ - -/*<replacement>*/ -var debugUtil = require('util'); -var debug = void 0; -if (debugUtil && debugUtil.debuglog) { - debug = debugUtil.debuglog('stream'); -} else { - debug = function () {}; -} -/*</replacement>*/ - -var BufferList = require('./internal/streams/BufferList'); -var destroyImpl = require('./internal/streams/destroy'); -var StringDecoder; - -util.inherits(Readable, Stream); - -var kProxyEvents = ['error', 'close', 'destroy', 'pause', 'resume']; - -function prependListener(emitter, event, fn) { - // Sadly this is not cacheable as some libraries bundle their own - // event emitter implementation with them. - if (typeof emitter.prependListener === 'function') return emitter.prependListener(event, fn); - - // This is a hack to make sure that our error handler is attached before any - // userland ones. NEVER DO THIS. This is here only because this code needs - // to continue to work with older versions of Node.js that do not include - // the prependListener() method. The goal is to eventually remove this hack. - if (!emitter._events || !emitter._events[event]) emitter.on(event, fn);else if (isArray(emitter._events[event])) emitter._events[event].unshift(fn);else emitter._events[event] = [fn, emitter._events[event]]; -} - -function ReadableState(options, stream) { - 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. - // These options can be provided separately as readableXXX and writableXXX. - var isDuplex = stream instanceof Duplex; - - // object stream flag. Used to make read(n) ignore n and to - // make all the buffer merging and length checks go away - this.objectMode = !!options.objectMode; - - if (isDuplex) this.objectMode = this.objectMode || !!options.readableObjectMode; - - // the point at which it stops calling _read() to fill the buffer - // Note: 0 is a valid value, means "don't call _read preemptively ever" - var hwm = options.highWaterMark; - var readableHwm = options.readableHighWaterMark; - var defaultHwm = this.objectMode ? 16 : 16 * 1024; - - if (hwm || hwm === 0) this.highWaterMark = hwm;else if (isDuplex && (readableHwm || readableHwm === 0)) this.highWaterMark = readableHwm;else this.highWaterMark = defaultHwm; - - // cast to ints. - this.highWaterMark = Math.floor(this.highWaterMark); - - // A linked list is used to store data chunks instead of an array because the - // linked list can remove elements from the beginning faster than - // array.shift() - this.buffer = new BufferList(); - this.length = 0; - this.pipes = null; - this.pipesCount = 0; - this.flowing = null; - this.ended = false; - this.endEmitted = false; - this.reading = false; - - // a flag to be able to tell if the event 'readable'/'data' is emitted - // 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 read call. - this.sync = true; - - // whenever we return null, then we set a flag to say - // that we're awaiting a 'readable' event emission. - this.needReadable = false; - this.emittedReadable = false; - this.readableListening = false; - this.resumeScheduled = false; - - // has it been destroyed - this.destroyed = false; - - // 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'; - - // the number of writers that are awaiting a drain event in .pipe()s - this.awaitDrain = 0; - - // if true, a maybeReadMore has been scheduled - this.readingMore = false; - - this.decoder = null; - this.encoding = null; - if (options.encoding) { - if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder; - this.decoder = new StringDecoder(options.encoding); - this.encoding = options.encoding; - } -} - -function Readable(options) { - Duplex = Duplex || require('./_stream_duplex'); - - if (!(this instanceof Readable)) return new Readable(options); - - this._readableState = new ReadableState(options, this); - - // legacy - this.readable = true; - - if (options) { - if (typeof options.read === 'function') this._read = options.read; - - if (typeof options.destroy === 'function') this._destroy = options.destroy; - } - - Stream.call(this); -} - -Object.defineProperty(Readable.prototype, 'destroyed', { - get: function () { - if (this._readableState === undefined) { - return false; - } - return this._readableState.destroyed; - }, - set: function (value) { - // we ignore the value if the stream - // has not been initialized yet - if (!this._readableState) { - return; - } - - // backward compatibility, the user is explicitly - // managing destroyed - this._readableState.destroyed = value; - } -}); - -Readable.prototype.destroy = destroyImpl.destroy; -Readable.prototype._undestroy = destroyImpl.undestroy; -Readable.prototype._destroy = function (err, cb) { - this.push(null); - cb(err); -}; - -// Manually shove something into the read() buffer. -// This returns true if the highWaterMark has not been hit yet, -// similar to how Writable.write() returns true if you should -// write() some more. -Readable.prototype.push = function (chunk, encoding) { - var state = this._readableState; - var skipChunkCheck; - - if (!state.objectMode) { - if (typeof chunk === 'string') { - encoding = encoding || state.defaultEncoding; - if (encoding !== state.encoding) { - chunk = Buffer.from(chunk, encoding); - encoding = ''; - } - skipChunkCheck = true; - } - } else { - skipChunkCheck = true; - } - - return readableAddChunk(this, chunk, encoding, false, skipChunkCheck); -}; - -// Unshift should *always* be something directly out of read() -Readable.prototype.unshift = function (chunk) { - return readableAddChunk(this, chunk, null, true, false); -}; - -function readableAddChunk(stream, chunk, encoding, addToFront, skipChunkCheck) { - var state = stream._readableState; - if (chunk === null) { - state.reading = false; - onEofChunk(stream, state); - } else { - var er; - if (!skipChunkCheck) er = chunkInvalid(state, chunk); - if (er) { - stream.emit('error', er); - } else if (state.objectMode || chunk && chunk.length > 0) { - if (typeof chunk !== 'string' && !state.objectMode && Object.getPrototypeOf(chunk) !== Buffer.prototype) { - chunk = _uint8ArrayToBuffer(chunk); - } - - if (addToFront) { - if (state.endEmitted) stream.emit('error', new Error('stream.unshift() after end event'));else addChunk(stream, state, chunk, true); - } else if (state.ended) { - stream.emit('error', new Error('stream.push() after EOF')); - } else { - state.reading = false; - if (state.decoder && !encoding) { - chunk = state.decoder.write(chunk); - if (state.objectMode || chunk.length !== 0) addChunk(stream, state, chunk, false);else maybeReadMore(stream, state); - } else { - addChunk(stream, state, chunk, false); - } - } - } else if (!addToFront) { - state.reading = false; - } - } - - return needMoreData(state); -} - -function addChunk(stream, state, chunk, addToFront) { - if (state.flowing && state.length === 0 && !state.sync) { - stream.emit('data', chunk); - stream.read(0); - } else { - // update the buffer info. - state.length += state.objectMode ? 1 : chunk.length; - if (addToFront) state.buffer.unshift(chunk);else state.buffer.push(chunk); - - if (state.needReadable) emitReadable(stream); - } - maybeReadMore(stream, state); -} - -function chunkInvalid(state, chunk) { - var er; - if (!_isUint8Array(chunk) && typeof chunk !== 'string' && chunk !== undefined && !state.objectMode) { - er = new TypeError('Invalid non-string/buffer chunk'); - } - return er; -} - -// if it's past the high water mark, we can push in some more. -// Also, if we have no data yet, we can stand some -// more bytes. This is to work around cases where hwm=0, -// such as the repl. Also, if the push() triggered a -// readable event, and the user called read(largeNumber) such that -// needReadable was set, then we ought to push more, so that another -// 'readable' event will be triggered. -function needMoreData(state) { - return !state.ended && (state.needReadable || state.length < state.highWaterMark || state.length === 0); -} - -Readable.prototype.isPaused = function () { - return this._readableState.flowing === false; -}; - -// backwards compatibility. -Readable.prototype.setEncoding = function (enc) { - if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder; - this._readableState.decoder = new StringDecoder(enc); - this._readableState.encoding = enc; - return this; -}; - -// Don't raise the hwm > 8MB -var MAX_HWM = 0x800000; -function computeNewHighWaterMark(n) { - if (n >= MAX_HWM) { - n = MAX_HWM; - } else { - // Get the next highest power of 2 to prevent increasing hwm excessively in - // tiny amounts - n--; - n |= n >>> 1; - n |= n >>> 2; - n |= n >>> 4; - n |= n >>> 8; - n |= n >>> 16; - n++; - } - return n; -} - -// This function is designed to be inlinable, so please take care when making -// changes to the function body. -function howMuchToRead(n, state) { - if (n <= 0 || state.length === 0 && state.ended) return 0; - if (state.objectMode) return 1; - if (n !== n) { - // Only flow one buffer at a time - if (state.flowing && state.length) return state.buffer.head.data.length;else return state.length; - } - // If we're asking for more than the current hwm, then raise the hwm. - if (n > state.highWaterMark) state.highWaterMark = computeNewHighWaterMark(n); - if (n <= state.length) return n; - // Don't have enough - if (!state.ended) { - state.needReadable = true; - return 0; - } - return state.length; -} - -// you can override either this method, or the async _read(n) below. -Readable.prototype.read = function (n) { - debug('read', n); - n = parseInt(n, 10); - var state = this._readableState; - var nOrig = n; - - if (n !== 0) state.emittedReadable = false; - - // if we're doing read(0) to trigger a readable event, but we - // already have a bunch of data in the buffer, then just trigger - // the 'readable' event and move on. - if (n === 0 && state.needReadable && (state.length >= state.highWaterMark || state.ended)) { - debug('read: emitReadable', state.length, state.ended); - if (state.length === 0 && state.ended) endReadable(this);else emitReadable(this); - return null; - } - - n = howMuchToRead(n, state); - - // if we've ended, and we're now clear, then finish it up. - if (n === 0 && state.ended) { - if (state.length === 0) endReadable(this); - return null; - } - - // All the actual chunk generation logic needs to be - // *below* the call to _read. The reason is that in certain - // synthetic stream cases, such as passthrough streams, _read - // may be a completely synchronous operation which may change - // the state of the read buffer, providing enough data when - // before there was *not* enough. - // - // So, the steps are: - // 1. Figure out what the state of things will be after we do - // a read from the buffer. - // - // 2. If that resulting state will trigger a _read, then call _read. - // Note that this may be asynchronous, or synchronous. Yes, it is - // deeply ugly to write APIs this way, but that still doesn't mean - // that the Readable class should behave improperly, as streams are - // designed to be sync/async agnostic. - // Take note if the _read call is sync or async (ie, if the read call - // has returned yet), so that we know whether or not it's safe to emit - // 'readable' etc. - // - // 3. Actually pull the requested chunks out of the buffer and return. - - // if we need a readable event, then we need to do some reading. - var doRead = state.needReadable; - debug('need readable', doRead); - - // if we currently have less than the highWaterMark, then also read some - if (state.length === 0 || state.length - n < state.highWaterMark) { - doRead = true; - debug('length less than watermark', doRead); - } - - // however, if we've ended, then there's no point, and if we're already - // reading, then it's unnecessary. - if (state.ended || state.reading) { - doRead = false; - debug('reading or ended', doRead); - } else if (doRead) { - debug('do read'); - state.reading = true; - state.sync = true; - // if the length is currently zero, then we *need* a readable event. - if (state.length === 0) state.needReadable = true; - // call internal read method - this._read(state.highWaterMark); - state.sync = false; - // If _read pushed data synchronously, then `reading` will be false, - // and we need to re-evaluate how much data we can return to the user. - if (!state.reading) n = howMuchToRead(nOrig, state); - } - - var ret; - if (n > 0) ret = fromList(n, state);else ret = null; - - if (ret === null) { - state.needReadable = true; - n = 0; - } else { - state.length -= n; - } - - if (state.length === 0) { - // If we have nothing in the buffer, then we want to know - // as soon as we *do* get something into the buffer. - if (!state.ended) state.needReadable = true; - - // If we tried to read() past the EOF, then emit end on the next tick. - if (nOrig !== n && state.ended) endReadable(this); - } - - if (ret !== null) this.emit('data', ret); - - return ret; -}; - -function onEofChunk(stream, state) { - if (state.ended) return; - if (state.decoder) { - var chunk = state.decoder.end(); - if (chunk && chunk.length) { - state.buffer.push(chunk); - state.length += state.objectMode ? 1 : chunk.length; - } - } - state.ended = true; - - // emit 'readable' now to make sure it gets picked up. - emitReadable(stream); -} - -// Don't emit readable right away in sync mode, because this can trigger -// another read() call => stack overflow. This way, it might trigger -// a nextTick recursion warning, but that's not so bad. -function emitReadable(stream) { - var state = stream._readableState; - state.needReadable = false; - if (!state.emittedReadable) { - debug('emitReadable', state.flowing); - state.emittedReadable = true; - if (state.sync) pna.nextTick(emitReadable_, stream);else emitReadable_(stream); - } -} - -function emitReadable_(stream) { - debug('emit readable'); - stream.emit('readable'); - flow(stream); -} - -// at this point, the user has presumably seen the 'readable' event, -// and called read() to consume some data. that may have triggered -// in turn another _read(n) call, in which case reading = true if -// it's in progress. -// However, if we're not ended, or reading, and the length < hwm, -// then go ahead and try to read some more preemptively. -function maybeReadMore(stream, state) { - if (!state.readingMore) { - state.readingMore = true; - pna.nextTick(maybeReadMore_, stream, state); - } -} - -function maybeReadMore_(stream, state) { - var len = state.length; - while (!state.reading && !state.flowing && !state.ended && state.length < state.highWaterMark) { - debug('maybeReadMore read 0'); - stream.read(0); - if (len === state.length) - // didn't get any data, stop spinning. - break;else len = state.length; - } - state.readingMore = false; -} - -// abstract method. to be overridden in specific implementation classes. -// call cb(er, data) where data is <= n in length. -// for virtual (non-string, non-buffer) streams, "length" is somewhat -// arbitrary, and perhaps not very meaningful. -Readable.prototype._read = function (n) { - this.emit('error', new Error('_read() is not implemented')); -}; - -Readable.prototype.pipe = function (dest, pipeOpts) { - var src = this; - var state = this._readableState; - - switch (state.pipesCount) { - case 0: - state.pipes = dest; - break; - case 1: - state.pipes = [state.pipes, dest]; - break; - default: - state.pipes.push(dest); - break; - } - state.pipesCount += 1; - debug('pipe count=%d opts=%j', state.pipesCount, pipeOpts); - - var doEnd = (!pipeOpts || pipeOpts.end !== false) && dest !== process.stdout && dest !== process.stderr; - - var endFn = doEnd ? onend : unpipe; - if (state.endEmitted) pna.nextTick(endFn);else src.once('end', endFn); - - dest.on('unpipe', onunpipe); - function onunpipe(readable, unpipeInfo) { - debug('onunpipe'); - if (readable === src) { - if (unpipeInfo && unpipeInfo.hasUnpiped === false) { - unpipeInfo.hasUnpiped = true; - cleanup(); - } - } - } - - function onend() { - debug('onend'); - dest.end(); - } - - // when the dest drains, it reduces the awaitDrain counter - // on the source. This would be more elegant with a .once() - // handler in flow(), but adding and removing repeatedly is - // too slow. - var ondrain = pipeOnDrain(src); - dest.on('drain', ondrain); - - var cleanedUp = false; - function cleanup() { - debug('cleanup'); - // cleanup event handlers once the pipe is broken - dest.removeListener('close', onclose); - dest.removeListener('finish', onfinish); - dest.removeListener('drain', ondrain); - dest.removeListener('error', onerror); - dest.removeListener('unpipe', onunpipe); - src.removeListener('end', onend); - src.removeListener('end', unpipe); - src.removeListener('data', ondata); - - cleanedUp = true; - - // if the reader is waiting for a drain event from this - // specific writer, then it would cause it to never start - // flowing again. - // So, if this is awaiting a drain, then we just call it now. - // If we don't know, then assume that we are waiting for one. - if (state.awaitDrain && (!dest._writableState || dest._writableState.needDrain)) ondrain(); - } - - // If the user pushes more data while we're writing to dest then we'll end up - // in ondata again. However, we only want to increase awaitDrain once because - // dest will only emit one 'drain' event for the multiple writes. - // => Introduce a guard on increasing awaitDrain. - var increasedAwaitDrain = false; - src.on('data', ondata); - function ondata(chunk) { - debug('ondata'); - increasedAwaitDrain = false; - var ret = dest.write(chunk); - if (false === ret && !increasedAwaitDrain) { - // If the user unpiped during `dest.write()`, it is possible - // to get stuck in a permanently paused state if that write - // also returned false. - // => Check whether `dest` is still a piping destination. - if ((state.pipesCount === 1 && state.pipes === dest || state.pipesCount > 1 && indexOf(state.pipes, dest) !== -1) && !cleanedUp) { - debug('false write response, pause', src._readableState.awaitDrain); - src._readableState.awaitDrain++; - increasedAwaitDrain = true; - } - src.pause(); - } - } - - // if the dest has an error, then stop piping into it. - // however, don't suppress the throwing behavior for this. - function onerror(er) { - debug('onerror', er); - unpipe(); - dest.removeListener('error', onerror); - if (EElistenerCount(dest, 'error') === 0) dest.emit('error', er); - } - - // Make sure our error handler is attached before userland ones. - prependListener(dest, 'error', onerror); - - // Both close and finish should trigger unpipe, but only once. - function onclose() { - dest.removeListener('finish', onfinish); - unpipe(); - } - dest.once('close', onclose); - function onfinish() { - debug('onfinish'); - dest.removeListener('close', onclose); - unpipe(); - } - dest.once('finish', onfinish); - - function unpipe() { - debug('unpipe'); - src.unpipe(dest); - } - - // tell the dest that it's being piped to - dest.emit('pipe', src); - - // start the flow if it hasn't been started already. - if (!state.flowing) { - debug('pipe resume'); - src.resume(); - } - - return dest; -}; - -function pipeOnDrain(src) { - return function () { - var state = src._readableState; - debug('pipeOnDrain', state.awaitDrain); - if (state.awaitDrain) state.awaitDrain--; - if (state.awaitDrain === 0 && EElistenerCount(src, 'data')) { - state.flowing = true; - flow(src); - } - }; -} - -Readable.prototype.unpipe = function (dest) { - var state = this._readableState; - var unpipeInfo = { hasUnpiped: false }; - - // if we're not piping anywhere, then do nothing. - if (state.pipesCount === 0) return this; - - // just one destination. most common case. - if (state.pipesCount === 1) { - // passed in one, but it's not the right one. - if (dest && dest !== state.pipes) return this; - - if (!dest) dest = state.pipes; - - // got a match. - state.pipes = null; - state.pipesCount = 0; - state.flowing = false; - if (dest) dest.emit('unpipe', this, unpipeInfo); - return this; - } - - // slow case. multiple pipe destinations. - - if (!dest) { - // remove all. - var dests = state.pipes; - var len = state.pipesCount; - state.pipes = null; - state.pipesCount = 0; - state.flowing = false; - - for (var i = 0; i < len; i++) { - dests[i].emit('unpipe', this, unpipeInfo); - }return this; - } - - // try to find the right one. - var index = indexOf(state.pipes, dest); - if (index === -1) return this; - - state.pipes.splice(index, 1); - state.pipesCount -= 1; - if (state.pipesCount === 1) state.pipes = state.pipes[0]; - - dest.emit('unpipe', this, unpipeInfo); - - return this; -}; - -// set up data events if they are asked for -// Ensure readable listeners eventually get something -Readable.prototype.on = function (ev, fn) { - var res = Stream.prototype.on.call(this, ev, fn); - - if (ev === 'data') { - // Start flowing on next tick if stream isn't explicitly paused - if (this._readableState.flowing !== false) this.resume(); - } else if (ev === 'readable') { - var state = this._readableState; - if (!state.endEmitted && !state.readableListening) { - state.readableListening = state.needReadable = true; - state.emittedReadable = false; - if (!state.reading) { - pna.nextTick(nReadingNextTick, this); - } else if (state.length) { - emitReadable(this); - } - } - } - - return res; -}; -Readable.prototype.addListener = Readable.prototype.on; - -function nReadingNextTick(self) { - debug('readable nexttick read 0'); - self.read(0); -} - -// pause() and resume() are remnants of the legacy readable stream API -// If the user uses them, then switch into old mode. -Readable.prototype.resume = function () { - var state = this._readableState; - if (!state.flowing) { - debug('resume'); - state.flowing = true; - resume(this, state); - } - return this; -}; - -function resume(stream, state) { - if (!state.resumeScheduled) { - state.resumeScheduled = true; - pna.nextTick(resume_, stream, state); - } -} - -function resume_(stream, state) { - if (!state.reading) { - debug('resume read 0'); - stream.read(0); - } - - state.resumeScheduled = false; - state.awaitDrain = 0; - stream.emit('resume'); - flow(stream); - if (state.flowing && !state.reading) stream.read(0); -} - -Readable.prototype.pause = function () { - debug('call pause flowing=%j', this._readableState.flowing); - if (false !== this._readableState.flowing) { - debug('pause'); - this._readableState.flowing = false; - this.emit('pause'); - } - return this; -}; - -function flow(stream) { - var state = stream._readableState; - debug('flow', state.flowing); - while (state.flowing && stream.read() !== null) {} -} - -// wrap an old-style stream as the async data source. -// This is *not* part of the readable stream interface. -// It is an ugly unfortunate mess of history. -Readable.prototype.wrap = function (stream) { - var _this = this; - - var state = this._readableState; - var paused = false; - - stream.on('end', function () { - debug('wrapped end'); - if (state.decoder && !state.ended) { - var chunk = state.decoder.end(); - if (chunk && chunk.length) _this.push(chunk); - } - - _this.push(null); - }); - - stream.on('data', function (chunk) { - debug('wrapped data'); - if (state.decoder) chunk = state.decoder.write(chunk); - - // don't skip over falsy values in objectMode - if (state.objectMode && (chunk === null || chunk === undefined)) return;else if (!state.objectMode && (!chunk || !chunk.length)) return; - - var ret = _this.push(chunk); - if (!ret) { - paused = true; - stream.pause(); - } - }); - - // proxy all the other methods. - // important when wrapping filters and duplexes. - for (var i in stream) { - if (this[i] === undefined && typeof stream[i] === 'function') { - this[i] = function (method) { - return function () { - return stream[method].apply(stream, arguments); - }; - }(i); - } - } - - // proxy certain important events. - for (var n = 0; n < kProxyEvents.length; n++) { - stream.on(kProxyEvents[n], this.emit.bind(this, kProxyEvents[n])); - } - - // when we try to consume some more bytes, simply unpause the - // underlying stream. - this._read = function (n) { - debug('wrapped _read', n); - if (paused) { - paused = false; - stream.resume(); - } - }; - - return this; -}; - -Object.defineProperty(Readable.prototype, 'readableHighWaterMark', { - // making it explicit this property is not enumerable - // because otherwise some prototype manipulation in - // userland will fail - enumerable: false, - get: function () { - return this._readableState.highWaterMark; - } -}); - -// exposed for testing purposes only. -Readable._fromList = fromList; - -// Pluck off n bytes from an array of buffers. -// Length is the combined lengths of all the buffers in the list. -// This function is designed to be inlinable, so please take care when making -// changes to the function body. -function fromList(n, state) { - // nothing buffered - if (state.length === 0) return null; - - var ret; - if (state.objectMode) ret = state.buffer.shift();else if (!n || n >= state.length) { - // read it all, truncate the list - if (state.decoder) ret = state.buffer.join('');else if (state.buffer.length === 1) ret = state.buffer.head.data;else ret = state.buffer.concat(state.length); - state.buffer.clear(); - } else { - // read part of list - ret = fromListPartial(n, state.buffer, state.decoder); - } - - return ret; -} - -// Extracts only enough buffered data to satisfy the amount requested. -// This function is designed to be inlinable, so please take care when making -// changes to the function body. -function fromListPartial(n, list, hasStrings) { - var ret; - if (n < list.head.data.length) { - // slice is the same for buffers and strings - ret = list.head.data.slice(0, n); - list.head.data = list.head.data.slice(n); - } else if (n === list.head.data.length) { - // first chunk is a perfect match - ret = list.shift(); - } else { - // result spans more than one buffer - ret = hasStrings ? copyFromBufferString(n, list) : copyFromBuffer(n, list); - } - return ret; -} - -// Copies a specified amount of characters from the list of buffered data -// chunks. -// This function is designed to be inlinable, so please take care when making -// changes to the function body. -function copyFromBufferString(n, list) { - var p = list.head; - var c = 1; - var ret = p.data; - n -= ret.length; - while (p = p.next) { - var str = p.data; - var nb = n > str.length ? str.length : n; - if (nb === str.length) ret += str;else ret += str.slice(0, n); - n -= nb; - if (n === 0) { - if (nb === str.length) { - ++c; - if (p.next) list.head = p.next;else list.head = list.tail = null; - } else { - list.head = p; - p.data = str.slice(nb); - } - break; - } - ++c; - } - list.length -= c; - return ret; -} - -// Copies a specified amount of bytes from the list of buffered data chunks. -// This function is designed to be inlinable, so please take care when making -// changes to the function body. -function copyFromBuffer(n, list) { - var ret = Buffer.allocUnsafe(n); - var p = list.head; - var c = 1; - p.data.copy(ret); - n -= p.data.length; - while (p = p.next) { - var buf = p.data; - var nb = n > buf.length ? buf.length : n; - buf.copy(ret, ret.length - n, 0, nb); - n -= nb; - if (n === 0) { - if (nb === buf.length) { - ++c; - if (p.next) list.head = p.next;else list.head = list.tail = null; - } else { - list.head = p; - p.data = buf.slice(nb); - } - break; - } - ++c; - } - list.length -= c; - return ret; -} - -function endReadable(stream) { - var state = stream._readableState; - - // If we get here before consuming all the bytes, then that is a - // bug in node. Should never happen. - if (state.length > 0) throw new Error('"endReadable()" called on non-empty stream'); - - if (!state.endEmitted) { - state.ended = true; - pna.nextTick(endReadableNT, state, stream); - } -} - -function endReadableNT(state, stream) { - // Check that we didn't get one last unshift. - if (!state.endEmitted && state.length === 0) { - state.endEmitted = true; - stream.readable = false; - stream.emit('end'); - } -} - -function indexOf(xs, x) { - for (var i = 0, l = xs.length; i < l; i++) { - if (xs[i] === x) return i; - } - return -1; -}
\ No newline at end of file |