52 lines
1.1 KiB
JavaScript
52 lines
1.1 KiB
JavaScript
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'use strict';
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var SyncReader = module.exports = function(buffer) {
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this._buffer = buffer;
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this._reads = [];
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};
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SyncReader.prototype.read = function(length, callback) {
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this._reads.push({
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length: Math.abs(length), // if length < 0 then at most this length
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allowLess: length < 0,
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func: callback
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});
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};
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SyncReader.prototype.process = function() {
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// as long as there is any data and read requests
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while (this._reads.length > 0 && this._buffer.length) {
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var read = this._reads[0];
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if (this._buffer.length && (this._buffer.length >= read.length || read.allowLess)) {
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// ok there is any data so that we can satisfy this request
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this._reads.shift(); // == read
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var buf = this._buffer;
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this._buffer = buf.slice(read.length);
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read.func.call(this, buf.slice(0, read.length));
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}
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else {
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break;
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}
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}
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if (this._reads.length > 0) {
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return new Error('There are some read requests waitng on finished stream');
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}
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if (this._buffer.length > 0) {
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return new Error('unrecognised content at end of stream');
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}
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};
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