src/crc.c

   1 #include "a/crc.h"
   2
   3 void a_crc8m_init(a_u8 table[0x100], a_u8 poly)
   4 {
   5     for (unsigned int c = 0; c != 0x100; ++c)
   6     {
   7         unsigned int value = c;
   8         for (unsigned int b = 8; b; --b)
   9         {
  10             unsigned int sig = A_U8_C(0x80) & value;
  11             value <<= 1;
  12             if (sig) { value ^= poly; }
  13         }
  14         table[c] = (a_u8)value;
  15     }
  16 }
  17 void a_crc8l_init(a_u8 table[0x100], a_u8 poly)
  18 {
  19     poly = a_u8_rev(poly);
  20     for (unsigned int c = 0; c != 0x100; ++c)
  21     {
  22         unsigned int value = c;
  23         for (unsigned int b = 8; b; --b)
  24         {
  25             unsigned int sig = value & 1;
  26             value >>= 1;
  27             if (sig) { value ^= poly; }
  28         }
  29         table[c] = (a_u8)value;
  30     }
  31 }
  32 a_u8 a_crc8(a_u8 const table[0x100], void const *pdata, a_size nbyte, a_u8 value)
  33 {
  34     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
  35     {
  36         value = table[value ^ *p++];
  37     }
  38     return value;
  39 }
  40
  41 void a_crc16m_init(a_u16 table[0x100], a_u16 poly)
  42 {
  43     for (unsigned int c = 0; c != 0x100; ++c)
  44     {
  45         unsigned int value = c << 8;
  46         for (unsigned int b = 8; b; --b)
  47         {
  48             unsigned int sig = A_U16_C(0x8000) & value;
  49             value <<= 1;
  50             if (sig) { value ^= poly; }
  51         }
  52         table[c] = (a_u16)value;
  53     }
  54 }
  55 void a_crc16l_init(a_u16 table[0x100], a_u16 poly)
  56 {
  57     poly = a_u16_rev(poly);
  58     for (unsigned int c = 0; c != 0x100; ++c)
  59     {
  60         unsigned int value = c;
  61         for (unsigned int b = 8; b; --b)
  62         {
  63             unsigned int sig = value & 1;
  64             value >>= 1;
  65             if (sig) { value ^= poly; }
  66         }
  67         table[c] = (a_u16)value;
  68     }
  69 }
  70 a_u16 a_crc16m(a_u16 const table[0x100], void const *pdata, a_size nbyte, a_u16 value)
  71 {
  72     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
  73     {
  74         value = (a_u16)((value << 8) ^ table[((value >> 8) ^ *p++) & 0xFF]);
  75     }
  76     return value;
  77 }
  78 a_u16 a_crc16l(a_u16 const table[0x100], void const *pdata, a_size nbyte, a_u16 value)
  79 {
  80     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
  81     {
  82         value = (a_u16)((value >> 8) ^ table[(value ^ *p++) & 0xFF]);
  83     }
  84     return value;
  85 }
  86
  87 void a_crc32m_init(a_u32 table[0x100], a_u32 poly)
  88 {
  89     for (a_u32 c = 0; c != 0x100; ++c)
  90     {
  91         a_u32 value = c << 24;
  92         for (unsigned int b = 8; b; --b)
  93         {
  94             a_u32 sig = A_U32_C(0x80000000) & value;
  95             value <<= 1;
  96             if (sig) { value ^= poly; }
  97         }
  98         table[c] = value;
  99     }
 100 }
 101 void a_crc32l_init(a_u32 table[0x100], a_u32 poly)
 102 {
 103     poly = a_u32_rev(poly);
 104     for (unsigned int c = 0; c != 0x100; ++c)
 105     {
 106         a_u32 value = c;
 107         for (unsigned int b = 8; b; --b)
 108         {
 109             a_u32 sig = value & 1;
 110             value >>= 1;
 111             if (sig) { value ^= poly; }
 112         }
 113         table[c] = value;
 114     }
 115 }
 116 a_u32 a_crc32m(a_u32 const table[0x100], void const *pdata, a_size nbyte, a_u32 value)
 117 {
 118     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
 119     {
 120         value = (value << 8) ^ table[((value >> 24) ^ *p++) & 0xFF];
 121     }
 122     return value;
 123 }
 124 a_u32 a_crc32l(a_u32 const table[0x100], void const *pdata, a_size nbyte, a_u32 value)
 125 {
 126     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
 127     {
 128         value = (value >> 8) ^ table[(value ^ *p++) & 0xFF];
 129     }
 130     return value;
 131 }
 132
 133 void a_crc64m_init(a_u64 table[0x100], a_u64 poly)
 134 {
 135     for (a_u64 c = 0; c != 0x100; ++c)
 136     {
 137         a_u64 value = c << 56;
 138         for (unsigned int b = 8; b; --b)
 139         {
 140             a_u64 sig = A_U64_C(0x8000000000000000) & value;
 141             value <<= 1;
 142             if (sig) { value ^= poly; }
 143         }
 144         table[c] = value;
 145     }
 146 }
 147 void a_crc64l_init(a_u64 table[0x100], a_u64 poly)
 148 {
 149     poly = a_u64_rev(poly);
 150     for (unsigned int c = 0; c != 0x100; ++c)
 151     {
 152         a_u64 value = c;
 153         for (unsigned int b = 8; b; --b)
 154         {
 155             a_u64 sig = value & 1;
 156             value >>= 1;
 157             if (sig) { value ^= poly; }
 158         }
 159         table[c] = value;
 160     }
 161 }
 162 a_u64 a_crc64m(a_u64 const table[0x100], void const *pdata, a_size nbyte, a_u64 value)
 163 {
 164     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
 165     {
 166         value = (value << 8) ^ table[((value >> 56) ^ *p++) & 0xFF];
 167     }
 168     return value;
 169 }
 170 a_u64 a_crc64l(a_u64 const table[0x100], void const *pdata, a_size nbyte, a_u64 value)
 171 {
 172     for (a_byte const *p = (a_byte const *)pdata; nbyte; --nbyte)
 173     {
 174         value = (value >> 8) ^ table[(value ^ *p++) & 0xFF];
 175     }
 176     return value;
 177 }