1 /* { dg-do run } */
2 /* { dg-options "-fno-strict-aliasing" } */
3 /* { dg-require-effective-target int32plus } */
4
5 #include <stdint.h>
6 #include <stdio.h>
7
8 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
9 #define av_le2ne32(x) (x)
10 #else
11 #define av_le2ne32(x) av_bswap32(x)
12 #endif
13
14 static __attribute__((always_inline)) inline __attribute__((const)) uint32_t av_bswap32(uint32_t x)
15 {
16 return ((((x) << 8 & 0xff00) | ((x) >> 8 & 0x00ff)) << 16 | ((((x) >> 16) << 8 & 0xff00) | (((x) >> 16) >> 8 & 0x00ff)));
17 }
18
19 typedef uint32_t AVCRC;
20
21 typedef enum {
22 AV_CRC_8_ATM,
23 AV_CRC_16_ANSI,
24 AV_CRC_16_CCITT,
25 AV_CRC_32_IEEE,
26 AV_CRC_32_IEEE_LE,
27 AV_CRC_16_ANSI_LE,
28 AV_CRC_24_IEEE = 12,
29 AV_CRC_MAX,
30 } AVCRCId;
31
32 int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size);
33
34
35
36
37
38
39 uint32_t av_crc(const AVCRC *ctx, uint32_t crc,
40 const uint8_t *buffer, size_t length) __attribute__((pure));
41 static struct {
42 uint8_t le;
43 uint8_t bits;
44 uint32_t poly;
45 } av_crc_table_params[AV_CRC_MAX] = {
46 [AV_CRC_8_ATM] = { 0, 8, 0x07 },
47 [AV_CRC_16_ANSI] = { 0, 16, 0x8005 },
48 [AV_CRC_16_CCITT] = { 0, 16, 0x1021 },
49 [AV_CRC_24_IEEE] = { 0, 24, 0x864CFB },
50 [AV_CRC_32_IEEE] = { 0, 32, 0x04C11DB7 },
51 [AV_CRC_32_IEEE_LE] = { 1, 32, 0xEDB88320 },
52 [AV_CRC_16_ANSI_LE] = { 1, 16, 0xA001 },
53 };
54 static AVCRC av_crc_table[AV_CRC_MAX][1024];
55
56
57 int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size)
58 {
59 unsigned i, j;
60 uint32_t c;
61
62 if (bits < 8 || bits > 32 || poly >= (1LL << bits))
63 return -1;
64 if (ctx_size != sizeof(AVCRC) * 257 && ctx_size != sizeof(AVCRC) * 1024)
65 return -1;
66
67 for (i = 0; i < 256; i++) {
68 if (le) {
69 for (c = i, j = 0; j < 8; j++)
70 c = (c >> 1) ^ (poly & (-(c & 1)));
71 ctx[i] = c;
72 } else {
73 for (c = i << 24, j = 0; j < 8; j++)
74 c = (c << 1) ^ ((poly << (32 - bits)) & (((int32_t) c) >> 31));
75 ctx[i] = av_bswap32(c);
76 }
77 }
78 ctx[256] = 1;
79
80 if (ctx_size >= sizeof(AVCRC) * 1024)
81 for (i = 0; i < 256; i++)
82 for (j = 0; j < 3; j++)
83 ctx[256 *(j + 1) + i] =
84 (ctx[256 * j + i] >> 8) ^ ctx[ctx[256 * j + i] & 0xFF];
85
86
87 return 0;
88 }
89
90 const AVCRC *av_crc_get_table(AVCRCId crc_id)
91 {
92 if (!av_crc_table[crc_id][(sizeof(av_crc_table[crc_id]) / sizeof((av_crc_table[crc_id])[0])) - 1])
93 if (av_crc_init(av_crc_table[crc_id],
94 av_crc_table_params[crc_id].le,
95 av_crc_table_params[crc_id].bits,
96 av_crc_table_params[crc_id].poly,
97 sizeof(av_crc_table[crc_id])) < 0)
98 return ((void *)0);
99
100 return av_crc_table[crc_id];
101 }
102
103 uint32_t av_crc(const AVCRC *ctx, uint32_t crc,
104 const uint8_t *buffer, size_t length)
105 {
106 const uint8_t *end = buffer + length;
107
108
109 if (!ctx[256]) {
110 while (((intptr_t) buffer & 3) && buffer < end)
111 crc = ctx[((uint8_t) crc) ^ *buffer++] ^ (crc >> 8);
112
113 while (buffer < end - 3) {
114 crc ^= av_le2ne32(*(const uint32_t *) buffer); buffer += 4;
115 crc = ctx[3 * 256 + ( crc & 0xFF)] ^
116 ctx[2 * 256 + ((crc >> 8 ) & 0xFF)] ^
117 ctx[1 * 256 + ((crc >> 16) & 0xFF)] ^
118 ctx[0 * 256 + ((crc >> 24) )];
119 }
120 }
121
122 while (buffer < end)
123 crc = ctx[((uint8_t) crc) ^ *buffer++] ^ (crc >> 8);
124
125 return crc;
126 }
127
128
129 int main(void)
130 {
131 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ || __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
132 uint8_t buf[1999];
133 int i;
134 unsigned
135 p[6][3] = { { AV_CRC_32_IEEE_LE, 0xEDB88320, 0x3D5CDD04 },
136 { AV_CRC_32_IEEE , 0x04C11DB7, 0xE0BAF5C0 },
137 { AV_CRC_24_IEEE , 0x864CFB , 0x326039 },
138 { AV_CRC_16_ANSI_LE, 0xA001 , 0xBFD8 },
139 { AV_CRC_16_ANSI , 0x8005 , 0xBB1F },
140 { AV_CRC_8_ATM , 0x07 , 0xE3 }
141 };
142 const AVCRC *ctx;
143
144 for (i = 0; i < sizeof(buf); i++)
145 buf[i] = i + i * i;
146
147 for (i = 0; i < 6; i++) {
148 int id = p[i][0];
149 uint32_t result;
150 ctx = av_crc_get_table (id);
151 result = av_crc(ctx, 0, buf, sizeof(buf));
152 if (result != p[i][2])
153 __builtin_abort ();
154 }
155 #endif
156 return 0;
157 }