forked from zhurui/management
60 lines
1.0 KiB
JavaScript
60 lines
1.0 KiB
JavaScript
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var eos = require('end-of-stream')
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var shift = require('stream-shift')
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module.exports = each
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function each (stream, fn, cb) {
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var want = true
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var error = null
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var ended = false
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var running = false
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var calling = false
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stream.on('readable', onreadable)
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onreadable()
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if (cb) eos(stream, {readable: true, writable: false}, done)
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return stream
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function done (err) {
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if (!error) error = err
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ended = true
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if (!running) cb(error)
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}
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function onreadable () {
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if (want) read()
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}
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function afterRead (err) {
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running = false
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if (err) {
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error = err
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if (ended) return cb(error)
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stream.destroy(err)
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return
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}
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if (ended) return cb(error)
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if (!calling) read()
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}
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function read () {
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while (!running && !ended) {
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want = false
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var data = shift(stream)
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if (ended) return
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if (data === null) {
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want = true
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return
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}
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running = true
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calling = true
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fn(data, afterRead)
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calling = false
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}
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}
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}
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