1 #include <stdio.h> 2 #include "crc32defs.h" 3 #include <inttypes.h> 4 5 #define ENTRIES_PER_LINE 4 6 7 #define LE_TABLE_SIZE (1 << CRC_LE_BITS) 8 #define BE_TABLE_SIZE (1 << CRC_BE_BITS) 9 10 static uint32_t crc32table_le[LE_TABLE_SIZE]; 11 static uint32_t crc32table_be[BE_TABLE_SIZE]; 12 13 /** 14 * crc32init_le() - allocate and initialize LE table data 15 * 16 * crc is the crc of the byte i; other entries are filled in based on the 17 * fact that crctable[i^j] = crctable[i] ^ crctable[j]. 18 * 19 */ 20 static void crc32init_le(void) 21 { 22 unsigned i, j; 23 uint32_t crc = 1; 24 25 crc32table_le[0] = 0; 26 27 for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) { 28 crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); 29 for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) 30 crc32table_le[i + j] = crc ^ crc32table_le[j]; 31 } 32 } 33 34 /** 35 * crc32init_be() - allocate and initialize BE table data 36 */ 37 static void crc32init_be(void) 38 { 39 unsigned i, j; 40 uint32_t crc = 0x80000000; 41 42 crc32table_be[0] = 0; 43 44 for (i = 1; i < BE_TABLE_SIZE; i <<= 1) { 45 crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0); 46 for (j = 0; j < i; j++) 47 crc32table_be[i + j] = crc ^ crc32table_be[j]; 48 } 49 } 50 51 static void output_table(uint32_t table[], int len, char *trans) 52 { 53 int i; 54 55 for (i = 0; i < len - 1; i++) { 56 if (i % ENTRIES_PER_LINE == 0) 57 printf("\n"); 58 printf("%s(0x%8.8xL), ", trans, table[i]); 59 } 60 printf("%s(0x%8.8xL)\n", trans, table[len - 1]); 61 } 62 63 int main(int argc, char** argv) 64 { 65 printf("/* this file is generated - do not edit */\n\n"); 66 67 if (CRC_LE_BITS > 1) { 68 crc32init_le(); 69 printf("static const u32 crc32table_le[] = {"); 70 output_table(crc32table_le, LE_TABLE_SIZE, "tole"); 71 printf("};\n"); 72 } 73 74 if (CRC_BE_BITS > 1) { 75 crc32init_be(); 76 printf("static const u32 crc32table_be[] = {"); 77 output_table(crc32table_be, BE_TABLE_SIZE, "tobe"); 78 printf("};\n"); 79 } 80 81 return 0; 82 } 83