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     a_byte const *p = (a_byte const *)pdata;
  35     a_byte const *q = (a_byte const *)pdata + nbyte;
  36     while (p != q) { value = table[value ^ *p++]; }
  37     return value;
  38 }
  39
  40 void a_crc16m_init(a_u16 table[0x100], a_u16 poly)
  41 {
  42     for (unsigned int c = 0; c != 0x100; ++c)
  43     {
  44         unsigned int value = c << 8;
  45         for (unsigned int b = 8; b; --b)
  46         {
  47             unsigned int sig = A_U16_C(0x8000) & value;
  48             value <<= 1;
  49             if (sig) { value ^= poly; }
  50         }
  51         table[c] = (a_u16)value;
  52     }
  53 }
  54 void a_crc16l_init(a_u16 table[0x100], a_u16 poly)
  55 {
  56     poly = a_u16_rev(poly);
  57     for (unsigned int c = 0; c != 0x100; ++c)
  58     {
  59         unsigned int value = c;
  60         for (unsigned int b = 8; b; --b)
  61         {
  62             unsigned int sig = value & 1;
  63             value >>= 1;
  64             if (sig) { value ^= poly; }
  65         }
  66         table[c] = (a_u16)value;
  67     }
  68 }
  69 a_u16 a_crc16m(a_u16 const table[0x100], void const *pdata, a_size nbyte, a_u16 value)
  70 {
  71     a_byte const *p = (a_byte const *)pdata;
  72     a_byte const *q = (a_byte const *)pdata + nbyte;
  73     while (p != q) { value = (a_u16)((value << 8) ^ table[((value >> 8) ^ *p++) & 0xFF]); }
  74     return value;
  75 }
  76 a_u16 a_crc16l(a_u16 const table[0x100], void const *pdata, a_size nbyte, a_u16 value)
  77 {
  78     a_byte const *p = (a_byte const *)pdata;
  79     a_byte const *q = (a_byte const *)pdata + nbyte;
  80     while (p != q) { value = (a_u16)((value >> 8) ^ table[(value ^ *p++) & 0xFF]); }
  81     return value;
  82 }
  83
  84 void a_crc32m_init(a_u32 table[0x100], a_u32 poly)
  85 {
  86     for (a_u32 c = 0; c != 0x100; ++c)
  87     {
  88         a_u32 value = c << 24;
  89         for (unsigned int b = 8; b; --b)
  90         {
  91             a_u32 sig = A_U32_C(0x80000000) & value;
  92             value <<= 1;
  93             if (sig) { value ^= poly; }
  94         }
  95         table[c] = value;
  96     }
  97 }
  98 void a_crc32l_init(a_u32 table[0x100], a_u32 poly)
  99 {
 100     poly = a_u32_rev(poly);
 101     for (unsigned int c = 0; c != 0x100; ++c)
 102     {
 103         a_u32 value = c;
 104         for (unsigned int b = 8; b; --b)
 105         {
 106             a_u32 sig = value & 1;
 107             value >>= 1;
 108             if (sig) { value ^= poly; }
 109         }
 110         table[c] = value;
 111     }
 112 }
 113 a_u32 a_crc32m(a_u32 const table[0x100], void const *pdata, a_size nbyte, a_u32 value)
 114 {
 115     a_byte const *p = (a_byte const *)pdata;
 116     a_byte const *q = (a_byte const *)pdata + nbyte;
 117     while (p != q) { value = (value << 8) ^ table[((value >> 24) ^ *p++) & 0xFF]; }
 118     return value;
 119 }
 120 a_u32 a_crc32l(a_u32 const table[0x100], void const *pdata, a_size nbyte, a_u32 value)
 121 {
 122     a_byte const *p = (a_byte const *)pdata;
 123     a_byte const *q = (a_byte const *)pdata + nbyte;
 124     while (p != q) { value = (value >> 8) ^ table[(value ^ *p++) & 0xFF]; }
 125     return value;
 126 }
 127
 128 void a_crc64m_init(a_u64 table[0x100], a_u64 poly)
 129 {
 130     for (a_u64 c = 0; c != 0x100; ++c)
 131     {
 132         a_u64 value = c << 56;
 133         for (unsigned int b = 8; b; --b)
 134         {
 135             a_u64 sig = A_U64_C(0x8000000000000000) & value;
 136             value <<= 1;
 137             if (sig) { value ^= poly; }
 138         }
 139         table[c] = value;
 140     }
 141 }
 142 void a_crc64l_init(a_u64 table[0x100], a_u64 poly)
 143 {
 144     poly = a_u64_rev(poly);
 145     for (unsigned int c = 0; c != 0x100; ++c)
 146     {
 147         a_u64 value = c;
 148         for (unsigned int b = 8; b; --b)
 149         {
 150             a_u64 sig = value & 1;
 151             value >>= 1;
 152             if (sig) { value ^= poly; }
 153         }
 154         table[c] = value;
 155     }
 156 }
 157 a_u64 a_crc64m(a_u64 const table[0x100], void const *pdata, a_size nbyte, a_u64 value)
 158 {
 159     a_byte const *p = (a_byte const *)pdata;
 160     a_byte const *q = (a_byte const *)pdata + nbyte;
 161     while (p != q) { value = (value << 8) ^ table[((value >> 56) ^ *p++) & 0xFF]; }
 162     return value;
 163 }
 164 a_u64 a_crc64l(a_u64 const table[0x100], void const *pdata, a_size nbyte, a_u64 value)
 165 {
 166     a_byte const *p = (a_byte const *)pdata;
 167     a_byte const *q = (a_byte const *)pdata + nbyte;
 168     while (p != q) { value = (value >> 8) ^ table[(value ^ *p++) & 0xFF]; }
 169     return value;
 170 }