99 lines
3.1 KiB
JavaScript
99 lines
3.1 KiB
JavaScript
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/*jslint browser: true, devel: true, bitwise: false, debug: true, eqeq: false, es5: true, evil: false, forin: false, newcap: false, nomen: true, plusplus: true, regexp: false, unparam: false, sloppy: true, stupid: false, sub: false, todo: true, vars: true, white: true */
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function DOMBufferStream(arrayBuffer, offset, length, bigEndian, global, parentOffset) {
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this.global = global;
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offset = offset || 0;
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length = length || (arrayBuffer.byteLength - offset);
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this.arrayBuffer = arrayBuffer.slice(offset, offset + length);
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this.view = new global.DataView(this.arrayBuffer, 0, this.arrayBuffer.byteLength);
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this.setBigEndian(bigEndian);
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this.offset = 0;
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this.parentOffset = (parentOffset || 0) + offset;
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}
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DOMBufferStream.prototype = {
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setBigEndian: function(bigEndian) {
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this.littleEndian = !bigEndian;
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},
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nextUInt8: function() {
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var value = this.view.getUint8(this.offset);
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this.offset += 1;
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return value;
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},
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nextInt8: function() {
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var value = this.view.getInt8(this.offset);
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this.offset += 1;
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return value;
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},
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nextUInt16: function() {
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var value = this.view.getUint16(this.offset, this.littleEndian);
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this.offset += 2;
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return value;
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},
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nextUInt32: function() {
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var value = this.view.getUint32(this.offset, this.littleEndian);
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this.offset += 4;
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return value;
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},
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nextInt16: function() {
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var value = this.view.getInt16(this.offset, this.littleEndian);
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this.offset += 2;
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return value;
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},
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nextInt32: function() {
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var value = this.view.getInt32(this.offset, this.littleEndian);
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this.offset += 4;
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return value;
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},
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nextFloat: function() {
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var value = this.view.getFloat32(this.offset, this.littleEndian);
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this.offset += 4;
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return value;
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},
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nextDouble: function() {
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var value = this.view.getFloat64(this.offset, this.littleEndian);
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this.offset += 8;
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return value;
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},
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nextBuffer: function(length) {
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//this won't work in IE10
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var value = this.arrayBuffer.slice(this.offset, this.offset + length);
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this.offset += length;
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return value;
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},
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remainingLength: function() {
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return this.arrayBuffer.byteLength - this.offset;
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},
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nextString: function(length) {
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var value = this.arrayBuffer.slice(this.offset, this.offset + length);
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value = String.fromCharCode.apply(null, new this.global.Uint8Array(value));
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this.offset += length;
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return value;
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},
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mark: function() {
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var self = this;
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return {
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openWithOffset: function(offset) {
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offset = (offset || 0) + this.offset;
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return new DOMBufferStream(self.arrayBuffer, offset, self.arrayBuffer.byteLength - offset, !self.littleEndian, self.global, self.parentOffset);
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},
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offset: this.offset,
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getParentOffset: function() {
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return self.parentOffset;
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}
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};
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},
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offsetFrom: function(marker) {
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return this.parentOffset + this.offset - (marker.offset + marker.getParentOffset());
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},
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skip: function(amount) {
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this.offset += amount;
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},
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branch: function(offset, length) {
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length = typeof length === 'number' ? length : this.arrayBuffer.byteLength - (this.offset + offset);
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return new DOMBufferStream(this.arrayBuffer, this.offset + offset, length, !this.littleEndian, this.global, this.parentOffset);
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}
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};
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module.exports = DOMBufferStream;
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