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#include <stdio.h>

#include "crc32defs.h"

#include <sys/types.h>

#define ENTRIES_PER_LINE 4

#define LE_TABLE_SIZE (1 << CRC_LE_BITS)

#define BE_TABLE_SIZE (1 << CRC_BE_BITS)

static u_int32_t crc32table_le[LE_TABLE_SIZE];

static u_int32_t crc32table_be[BE_TABLE_SIZE];

/**

 * crc32init_le() - allocate and initialize LE table data

 *

 * crc is the crc of the byte i; other entries are filled in based on the

 * fact that crctable[i^j] = crctable[i] ^ crctable[j].

 *

 */

static void crc32init_le(void)

{

        unsigned i, j;

        u_int32_t crc = 1;

        crc32table_le[0] = 0;

        for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) {

                crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);

                for (j = 0; j < LE_TABLE_SIZE; j += 2 * i)

                        crc32table_le[i + j] = crc ^ crc32table_le[j];

        }

}

/**

 * crc32init_be() - allocate and initialize BE table data

 */

static void crc32init_be(void)

{

        unsigned i, j;

        u_int32_t crc = 0x80000000;

        crc32table_be[0] = 0;

        for (i = 1; i < BE_TABLE_SIZE; i <<= 1) {

                crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0);

                for (j = 0; j < i; j++)

                        crc32table_be[i + j] = crc ^ crc32table_be[j];

        }

}

static void output_table(u_int32_t table[], int len, char *trans)

{

        int i;

        for (i = 0; i < len - 1; i++) {

                if (i % ENTRIES_PER_LINE == 0)

                        printf("\n");

                printf("%s(0x%8.8xL), ", trans, table[i]);

        }

        printf("%s(0x%8.8xL)\n", trans, table[len - 1]);

}

int main(int argc, char** argv)

{

        printf("/* this file is generated - do not edit */\n\n");

        if (CRC_LE_BITS > 1) {

                crc32init_le();

                printf("static const u32 crc32table_le[] = {");

                output_table(crc32table_le, LE_TABLE_SIZE, "tole");

                printf("};\n");

        }

        if (CRC_BE_BITS > 1) {

                crc32init_be();

                printf("static const u32 crc32table_be[] = {");

                output_table(crc32table_be, BE_TABLE_SIZE, "tobe");

                printf("};\n");

        }

        return 0;

}