FFmpeg: libavutil/base64.c Source File

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libavutil

base64.c

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1 /*

3 *

4 * This file is part of FFmpeg.

5 *

6 * FFmpeg is free software; you can redistribute it and/or

7 * modify it under the terms of the GNU Lesser General Public

8 * License as published by the Free Software Foundation; either

9 * version 2.1 of the License, or (at your option) any later version.

10 *

11 * FFmpeg is distributed in the hope that it will be useful,

12 * but WITHOUT ANY WARRANTY; without even the implied warranty of

13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

14 * Lesser General Public License for more details.

15 *

16 * You should have received a copy of the GNU Lesser General Public

17 * License along with FFmpeg; if not, write to the Free Software

18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

19 */

21 /**

22 * @file

23 * @brief Base64 encode/decode

24 * @author Ryan Martell <rdm4@martellventures.com> (with lots of Michael)

25 */

27 #include "common.h"

28 #include "base64.h"

29 #include "intreadwrite.h"

30 #include "timer.h"

32 /* ---------------- private code */

33 static const uint8_t map2[256] =

34 {

35 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

36 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

37 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

38 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

39 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

40 0xff, 0xff, 0xff,

42 0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36,

43 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff,

44 0xff, 0xff, 0xfe, 0xff, 0xff, 0xff, 0x00, 0x01,

45 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,

46 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,

47 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19,

48 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1a, 0x1b,

49 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,

50 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,

51 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33,

53 0xff, 0xff, 0xff, 0xff, 0xff,

54 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

55 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

56 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

57 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

58 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

59 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

60 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

61 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

62 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

63 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

64 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

65 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

66 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

67 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

68 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

69 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,

70 };

72 #define BASE64_DEC_STEP(i) do { \

73 bits = map2[in[i]]; \

74 if (bits & 0x80) \

75 goto out ## i; \

76 v = i ? (v << 6) + bits : bits; \

77 } while(0)

79 int av_base64_decode(uint8_t *out, const char *in_str, int out_size)

80 {

81 uint8_t *dst = out;

82 uint8_t *end;

83 // no sign extension

84 const uint8_t *in = in_str;

85 unsigned bits = 0xff;

86 unsigned v;

88 if (!out)

89 goto validity_check;

91 end = out + out_size;

92 while (end - dst > 3) {

93 BASE64_DEC_STEP(0);

94 BASE64_DEC_STEP(1);

95 BASE64_DEC_STEP(2);

96 BASE64_DEC_STEP(3);

97 // Using AV_WB32 directly confuses compiler

98 v = av_be2ne32(v << 8);

99 AV_WN32(dst, v);

100 dst += 3;

101 in += 4;

102 }

103 if (end - dst) {

104 BASE64_DEC_STEP(0);

105 BASE64_DEC_STEP(1);

106 BASE64_DEC_STEP(2);

107 BASE64_DEC_STEP(3);

108 *dst++ = v >> 16;

109 if (end - dst)

110 *dst++ = v >> 8;

111 if (end - dst)

112 *dst++ = v;

113 in += 4;

114 }

115 validity_check:

116 while (1) {

117 BASE64_DEC_STEP(0);

118 in++;

119 BASE64_DEC_STEP(0);

120 in++;

121 BASE64_DEC_STEP(0);

122 in++;

123 BASE64_DEC_STEP(0);

124 in++;

125 }

126

127 out3:

128 *dst++ = v >> 10;

129 v <<= 2;

130 out2:

131 *dst++ = v >> 4;

132 out1:

133 out0:

134 return bits & 1 ? AVERROR_INVALIDDATA : out ? dst - out : 0;

135 }

136

137 /*****************************************************************************

138 * b64_encode: Stolen from VLC's http.c.

139 * Simplified by Michael.

140 * Fixed edge cases and made it work from data (vs. strings) by Ryan.

141 *****************************************************************************/

142

143 char *av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size)

144 {

145 static const char b64[] =

146 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

147 char *ret, *dst;

148 unsigned i_bits = 0;

149 int i_shift = 0;

150 int bytes_remaining = in_size;

151

152 if (in_size >= UINT_MAX / 4 ||

153 out_size < AV_BASE64_SIZE(in_size))

154 return NULL;

155 ret = dst = out;

156 while (bytes_remaining > 3) {

157 i_bits = AV_RB32(in);

158 in += 3; bytes_remaining -= 3;

159 *dst++ = b64[ i_bits>>26 ];

160 *dst++ = b64[(i_bits>>20) & 0x3F];

161 *dst++ = b64[(i_bits>>14) & 0x3F];

162 *dst++ = b64[(i_bits>>8 ) & 0x3F];

163 }

164 i_bits = 0;

165 while (bytes_remaining) {

166 i_bits = (i_bits << 8) + *in++;

167 bytes_remaining--;

168 i_shift += 8;

169 }

170 while (i_shift > 0) {

171 *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f];

172 i_shift -= 6;

173 }

174 while ((dst - ret) & 3)

175 *dst++ = '=';

176 *dst = '0円';

177

178 return ret;

179 }

out

FILE * out

Definition: movenc.c:54

out_size

int out_size

Definition: movenc.c:55

intreadwrite.h

bits

uint8_t bits

Definition: vp3data.h:141

av_be2ne32

#define av_be2ne32(x)

Definition: bswap.h:93

NULL

#define NULL

Definition: coverity.c:32

map2

static const uint8_t map2[256]

Definition: base64.c:33

timer.h

av_base64_decode

int av_base64_decode(uint8_t *out, const char *in_str, int out_size)

Decode a base64-encoded string.

Definition: base64.c:79

base64.h

AV_WN32

#define AV_WN32(p, v)

Definition: intreadwrite.h:376

AV_RB32

uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32

Definition: bytestream.h:96

AV_BASE64_SIZE

#define AV_BASE64_SIZE(x)

Calculate the output size needed to base64-encode x bytes to a null-terminated string.

Definition: base64.h:66

common.h

ret

Definition: filter_design.txt:187

av_base64_encode

char * av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size)

Encode data to base64 and null-terminate.

Definition: base64.c:143

AVERROR_INVALIDDATA

#define AVERROR_INVALIDDATA

Invalid data found when processing input.

Definition: error.h:61

BASE64_DEC_STEP

#define BASE64_DEC_STEP(i)

Definition: base64.c:72

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