mirror of https://github.com/jkjoy/sunpeiwen.git
86 lines
2.4 KiB
JavaScript
86 lines
2.4 KiB
JavaScript
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// Ported from https://github.com/mafintosh/pump with
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// permission from the author, Mathias Buus (@mafintosh).
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'use strict';
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var eos;
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function once(callback) {
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var called = false;
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return function () {
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if (called) return;
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called = true;
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callback.apply(void 0, arguments);
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};
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}
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var _require$codes = require('../../../errors').codes,
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ERR_MISSING_ARGS = _require$codes.ERR_MISSING_ARGS,
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ERR_STREAM_DESTROYED = _require$codes.ERR_STREAM_DESTROYED;
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function noop(err) {
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// Rethrow the error if it exists to avoid swallowing it
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if (err) throw err;
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}
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function isRequest(stream) {
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return stream.setHeader && typeof stream.abort === 'function';
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}
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function destroyer(stream, reading, writing, callback) {
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callback = once(callback);
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var closed = false;
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stream.on('close', function () {
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closed = true;
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});
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if (eos === undefined) eos = require('./end-of-stream');
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eos(stream, {
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readable: reading,
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writable: writing
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}, function (err) {
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if (err) return callback(err);
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closed = true;
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callback();
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});
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var destroyed = false;
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return function (err) {
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if (closed) return;
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if (destroyed) return;
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destroyed = true;
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// request.destroy just do .end - .abort is what we want
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if (isRequest(stream)) return stream.abort();
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if (typeof stream.destroy === 'function') return stream.destroy();
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callback(err || new ERR_STREAM_DESTROYED('pipe'));
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};
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}
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function call(fn) {
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fn();
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}
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function pipe(from, to) {
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return from.pipe(to);
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}
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function popCallback(streams) {
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if (!streams.length) return noop;
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if (typeof streams[streams.length - 1] !== 'function') return noop;
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return streams.pop();
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}
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function pipeline() {
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for (var _len = arguments.length, streams = new Array(_len), _key = 0; _key < _len; _key++) {
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streams[_key] = arguments[_key];
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}
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var callback = popCallback(streams);
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if (Array.isArray(streams[0])) streams = streams[0];
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if (streams.length < 2) {
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throw new ERR_MISSING_ARGS('streams');
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}
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var error;
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var destroys = streams.map(function (stream, i) {
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var reading = i < streams.length - 1;
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var writing = i > 0;
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return destroyer(stream, reading, writing, function (err) {
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if (!error) error = err;
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if (err) destroys.forEach(call);
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if (reading) return;
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destroys.forEach(call);
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callback(error);
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});
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});
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return streams.reduce(pipe);
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}
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module.exports = pipeline;
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