120 lines
2.5 KiB
JavaScript
120 lines
2.5 KiB
JavaScript
var events = require('events');
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var util = require('util');
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function Stream() {
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events.EventEmitter.call(this);
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}
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util.inherits(Stream, events.EventEmitter);
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module.exports = Stream;
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// Backwards-compat with node 0.4.x
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Stream.Stream = Stream;
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Stream.prototype.pipe = function(dest, options) {
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var source = this;
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function ondata(chunk) {
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if (dest.writable) {
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if (false === dest.write(chunk) && source.pause) {
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source.pause();
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}
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}
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}
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source.on('data', ondata);
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function ondrain() {
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if (source.readable && source.resume) {
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source.resume();
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}
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}
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dest.on('drain', ondrain);
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// If the 'end' option is not supplied, dest.end() will be called when
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// source gets the 'end' or 'close' events. Only dest.end() once, and
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// only when all sources have ended.
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if (!dest._isStdio && (!options || options.end !== false)) {
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dest._pipeCount = dest._pipeCount || 0;
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dest._pipeCount++;
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source.on('end', onend);
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source.on('close', onclose);
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}
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var didOnEnd = false;
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function onend() {
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if (didOnEnd) return;
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didOnEnd = true;
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dest._pipeCount--;
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// remove the listeners
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cleanup();
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if (dest._pipeCount > 0) {
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// waiting for other incoming streams to end.
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return;
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}
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dest.end();
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}
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function onclose() {
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if (didOnEnd) return;
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didOnEnd = true;
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dest._pipeCount--;
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// remove the listeners
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cleanup();
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if (dest._pipeCount > 0) {
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// waiting for other incoming streams to end.
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return;
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}
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dest.destroy();
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}
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// don't leave dangling pipes when there are errors.
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function onerror(er) {
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cleanup();
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if (this.listeners('error').length === 0) {
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throw er; // Unhandled stream error in pipe.
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}
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}
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source.on('error', onerror);
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dest.on('error', onerror);
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// remove all the event listeners that were added.
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function cleanup() {
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source.removeListener('data', ondata);
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dest.removeListener('drain', ondrain);
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source.removeListener('end', onend);
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source.removeListener('close', onclose);
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source.removeListener('error', onerror);
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dest.removeListener('error', onerror);
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source.removeListener('end', cleanup);
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source.removeListener('close', cleanup);
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dest.removeListener('end', cleanup);
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dest.removeListener('close', cleanup);
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}
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source.on('end', cleanup);
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source.on('close', cleanup);
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dest.on('end', cleanup);
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dest.on('close', cleanup);
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dest.emit('pipe', source);
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// Allow for unix-like usage: A.pipe(B).pipe(C)
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return dest;
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};
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