GNU libmicrohttpd  0.9.72
base64.c
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1 /*
2  * This code implements the BASE64 algorithm.
3  * This code is in the public domain; do with it what you wish.
4  *
5  * @file base64.c
6  * @brief This code implements the BASE64 algorithm
7  * @author Matthieu Speder
8  */
9 #include "base64.h"
10 
11 static const char base64_digits[] =
12 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
13  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
14  0, 0, 0, 0, 0, 62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
15  0, 0, 0, -1, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
16  14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0, 0, 0, 26,
17  27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44,
18  45, 46, 47, 48, 49, 50, 51, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
19  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
20  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
21  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
22  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
23  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
24 
25 
26 char *
27 BASE64Decode (const char*src)
28 {
29  size_t in_len = strlen (src);
30  char*dest;
31  char*result;
32 
33  if (in_len % 4)
34  {
35  /* Wrong base64 string length */
36  return NULL;
37  }
38  result = dest = malloc (in_len / 4 * 3 + 1);
39  if (NULL == result)
40  return NULL; /* out of memory */
41  while (*src)
42  {
43  char a = base64_digits[(unsigned char) *(src++)];
44  char b = base64_digits[(unsigned char) *(src++)];
45  char c = base64_digits[(unsigned char) *(src++)];
46  char d = base64_digits[(unsigned char) *(src++)];
47  *(dest++) = (a << 2) | ((b & 0x30) >> 4);
48  if (c == (char) -1)
49  break;
50  *(dest++) = ((b & 0x0f) << 4) | ((c & 0x3c) >> 2);
51  if (d == (char) -1)
52  break;
53  *(dest++) = ((c & 0x03) << 6) | d;
54  }
55  *dest = 0;
56  return result;
57 }
58 
59 
60 /* end of base64.c */
static const char base64_digits[]
Definition: base64.c:11
char * BASE64Decode(const char *src)
Definition: base64.c:27
#define NULL
Definition: reason_phrase.c:30