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
|
// Copyright 2011 Google Inc. All Rights Reserved.
#include "globals.h"
#include "scoped_ptr.h"
#include <vector>
namespace art {
static const byte kMap[256] = {
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 62, 255, 255, 255, 63,
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 255, 255,
255, 254, 255, 255, 255, 0, 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, 255, 255, 255, 255, 255,
255, 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, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255
};
byte* DecodeBase64(const char* src, size_t* dst_size) {
std::vector<byte> tmp;
unsigned long t = 0, y = 0;
int g = 3;
for (size_t i = 0; src[i] != '\0'; ++i) {
byte c = kMap[src[i] & 0xFF];
if (c == 255) continue;
// the final = symbols are read and used to trim the remaining bytes
if (c == 254) {
c = 0;
// prevent g < 0 which would potentially allow an overflow later
if (--g < 0) {
return NULL;
}
} else if (g != 3) {
// we only allow = to be at the end
return NULL;
}
t = (t << 6) | c;
if (++y == 4) {
tmp.push_back((t >> 16) & 255);
if (g > 1) {
tmp.push_back((t >> 8) & 255);
}
if (g > 2) {
tmp.push_back(t & 255);
}
y = t = 0;
}
}
if (y != 0) {
return NULL;
}
scoped_ptr<byte> dst(new byte[tmp.size()]);
if (dst_size != NULL) {
*dst_size = tmp.size();
}
std::copy(tmp.begin(), tmp.end(), dst.get());
return dst.release();
}
};
|