1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
/** @fileOverview Bit array codec implementations.
*
* @author Marco Munizaga
*/
//patch arraybuffers if they don't exist
if (typeof(ArrayBuffer) === 'undefined') {
(function(globals){
"use strict";
globals.ArrayBuffer = function(){};
globals.DataView = function(){};
}(this));
}
/** @namespace ArrayBuffer */
sjcl.codec.arrayBuffer = {
/** Convert from a bitArray to an ArrayBuffer.
* Will default to 8byte padding if padding is undefined*/
fromBits: function (arr, padding, padding_count) {
var out, i, ol, tmp, smallest;
padding = padding==undefined ? true : padding
padding_count = padding_count || 8
if (arr.length === 0) {
return new ArrayBuffer(0);
}
ol = sjcl.bitArray.bitLength(arr)/8;
//check to make sure the bitLength is divisible by 8, if it isn't
//we can't do anything since arraybuffers work with bytes, not bits
if ( sjcl.bitArray.bitLength(arr)%8 !== 0 ) {
throw new sjcl.exception.invalid("Invalid bit size, must be divisble by 8 to fit in an arraybuffer correctly")
}
if (padding && ol%padding_count !== 0){
ol += padding_count - (ol%padding_count);
}
//padded temp for easy copying
tmp = new DataView(new ArrayBuffer(arr.length*4));
for (i=0; i<arr.length; i++) {
tmp.setUint32(i*4, (arr[i]<<32)); //get rid of the higher bits
}
//now copy the final message if we are not going to 0 pad
out = new DataView(new ArrayBuffer(ol));
//save a step when the tmp and out bytelength are ===
if (out.byteLength === tmp.byteLength){
return tmp.buffer;
}
smallest = tmp.byteLength < out.byteLength ? tmp.byteLength : out.byteLength;
for(i=0; i<smallest; i++){
out.setUint8(i,tmp.getUint8(i));
}
return out.buffer
},
toBits: function (buffer) {
var i, out=[], len, inView, tmp;
if (buffer.byteLength === 0) {
return [];
}
inView = new DataView(buffer);
len = inView.byteLength - inView.byteLength%4;
for (var i = 0; i < len; i+=4) {
out.push(inView.getUint32(i));
}
if (inView.byteLength%4 != 0) {
tmp = new DataView(new ArrayBuffer(4));
for (var i = 0, l = inView.byteLength%4; i < l; i++) {
//we want the data to the right, because partial slices off the starting bits
tmp.setUint8(i+4-l, inView.getUint8(len+i)); // big-endian,
}
out.push(
sjcl.bitArray.partial( (inView.byteLength%4)*8, tmp.getUint32(0) )
);
}
return out;
},
/** Prints a hex output of the buffer contents, akin to hexdump **/
hexDumpBuffer: function(buffer){
var stringBufferView = new DataView(buffer)
var string = ''
var pad = function (n, width) {
n = n + '';
return n.length >= width ? n : new Array(width - n.length + 1).join('0') + n;
}
for (var i = 0; i < stringBufferView.byteLength; i+=2) {
if (i%16 == 0) string += ('\n'+(i).toString(16)+'\t')
string += ( pad(stringBufferView.getUint16(i).toString(16),4) + ' ')
}
if ( typeof console === undefined ){
console = console || {log:function(){}} //fix for IE
}
console.log(string.toUpperCase())
}
};
|
