94 lines
1.7 KiB
JavaScript
94 lines
1.7 KiB
JavaScript
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'use strict';
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var util = require('util');
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var Transform = require('stream').Transform;
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function ctor(options, transform) {
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util.inherits(FirstChunk, Transform);
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if (typeof options === 'function') {
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transform = options;
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options = {};
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}
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if (typeof transform !== 'function') {
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throw new Error('transform function required');
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}
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function FirstChunk(options2) {
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if (!(this instanceof FirstChunk)) {
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return new FirstChunk(options2);
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}
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Transform.call(this, options2);
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this._firstChunk = true;
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this._transformCalled = false;
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this._minSize = options.minSize;
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}
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FirstChunk.prototype._transform = function (chunk, enc, cb) {
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this._enc = enc;
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if (this._firstChunk) {
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this._firstChunk = false;
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if (this._minSize == null) {
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transform.call(this, chunk, enc, cb);
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this._transformCalled = true;
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return;
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}
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this._buffer = chunk;
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cb();
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return;
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}
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if (this._minSize == null) {
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this.push(chunk);
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cb();
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return;
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}
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if (this._buffer.length < this._minSize) {
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this._buffer = Buffer.concat([this._buffer, chunk]);
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cb();
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return;
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}
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if (this._buffer.length >= this._minSize) {
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transform.call(this, this._buffer.slice(), enc, function () {
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this.push(chunk);
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cb();
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}.bind(this));
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this._transformCalled = true;
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this._buffer = false;
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return;
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}
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this.push(chunk);
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cb();
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};
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FirstChunk.prototype._flush = function (cb) {
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if (!this._buffer) {
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cb();
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return;
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}
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if (this._transformCalled) {
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this.push(this._buffer);
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cb();
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} else {
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transform.call(this, this._buffer.slice(), this._enc, cb);
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}
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};
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return FirstChunk;
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}
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module.exports = function () {
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return ctor.apply(ctor, arguments)();
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};
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module.exports.ctor = ctor;
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