51 lines
895 B
JavaScript
51 lines
895 B
JavaScript
'use strict';
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function hasListeners(stream) {
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return !!(stream.listenerCount('readable') || stream.listenerCount('data'));
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}
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function sink(stream) {
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var sinkAdded = false;
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function addSink() {
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if (sinkAdded) {
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return;
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}
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if (hasListeners(stream)) {
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return;
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}
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sinkAdded = true;
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stream.resume();
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}
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function removeSink(evt) {
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if (evt !== 'readable' && evt !== 'data') {
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return;
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}
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if (hasListeners(stream)) {
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sinkAdded = false;
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}
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process.nextTick(addSink);
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}
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function markSink() {
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sinkAdded = true;
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}
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stream.on('newListener', removeSink);
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stream.on('removeListener', removeSink);
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stream.on('piping', markSink);
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// Sink the stream to start flowing
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// Do this on nextTick, it will flow at slowest speed of piped streams
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process.nextTick(addSink);
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return stream;
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}
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module.exports = sink;
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