123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657 |
- "use strict";
- var DataReader = require("./DataReader");
- var utils = require("../utils");
- function ArrayReader(data) {
- DataReader.call(this, data);
- for(var i = 0; i < this.data.length; i++) {
- data[i] = data[i] & 0xFF;
- }
- }
- utils.inherits(ArrayReader, DataReader);
- /**
- * @see DataReader.byteAt
- */
- ArrayReader.prototype.byteAt = function(i) {
- return this.data[this.zero + i];
- };
- /**
- * @see DataReader.lastIndexOfSignature
- */
- ArrayReader.prototype.lastIndexOfSignature = function(sig) {
- var sig0 = sig.charCodeAt(0),
- sig1 = sig.charCodeAt(1),
- sig2 = sig.charCodeAt(2),
- sig3 = sig.charCodeAt(3);
- for (var i = this.length - 4; i >= 0; --i) {
- if (this.data[i] === sig0 && this.data[i + 1] === sig1 && this.data[i + 2] === sig2 && this.data[i + 3] === sig3) {
- return i - this.zero;
- }
- }
- return -1;
- };
- /**
- * @see DataReader.readAndCheckSignature
- */
- ArrayReader.prototype.readAndCheckSignature = function (sig) {
- var sig0 = sig.charCodeAt(0),
- sig1 = sig.charCodeAt(1),
- sig2 = sig.charCodeAt(2),
- sig3 = sig.charCodeAt(3),
- data = this.readData(4);
- return sig0 === data[0] && sig1 === data[1] && sig2 === data[2] && sig3 === data[3];
- };
- /**
- * @see DataReader.readData
- */
- ArrayReader.prototype.readData = function(size) {
- this.checkOffset(size);
- if(size === 0) {
- return [];
- }
- var result = this.data.slice(this.zero + this.index, this.zero + this.index + size);
- this.index += size;
- return result;
- };
- module.exports = ArrayReader;
|