Darrick J. Wongcrc32: bolt on crc32c46c580114 years agoHistory
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#include <stdio.h>#include "../include/generated/autoconf.h"#include "crc32defs.h"#include <inttypes.h> #define ENTRIES_PER_LINE 4 #if CRC_LE_BITS > 8# define LE_TABLE_ROWS (CRC_LE_BITS/8)# define LE_TABLE_SIZE 256#else# define LE_TABLE_ROWS 1# define LE_TABLE_SIZE (1 << CRC_LE_BITS)#endif #if CRC_BE_BITS > 8# define BE_TABLE_ROWS (CRC_BE_BITS/8)# define BE_TABLE_SIZE 256#else# define BE_TABLE_ROWS 1# define BE_TABLE_SIZE (1 << CRC_BE_BITS)#endif static uint32_t crc32table_le[LE_TABLE_ROWS][256];static uint32_t crc32table_be[BE_TABLE_ROWS][256];static uint32_t crc32ctable_le[LE_TABLE_ROWS][256]; /** * 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_generic(const uint32_t polynomial,				 uint32_t (*tab)[256]){	unsigned i, j;	uint32_t crc = 1; 	tab[0][0] = 0; 	for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) {		crc = (crc >> 1) ^ ((crc & 1) ? polynomial : 0);		for (j = 0; j < LE_TABLE_SIZE; j += 2 * i)			tab[0][i + j] = crc ^ tab[0][j];	}	for (i = 0; i < LE_TABLE_SIZE; i++) {		crc = tab[0][i];		for (j = 1; j < LE_TABLE_ROWS; j++) {			crc = tab[0][crc & 0xff] ^ (crc >> 8);			tab[j][i] = crc;		}	}} static void crc32init_le(void){	crc32init_le_generic(CRCPOLY_LE, crc32table_le);} static void crc32cinit_le(void){	crc32init_le_generic(CRC32C_POLY_LE, crc32ctable_le);} /** * crc32init_be() - allocate and initialize BE table data */static void crc32init_be(void){	unsigned i, j;	uint32_t crc = 0x80000000; 	crc32table_be[0][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[0][i + j] = crc ^ crc32table_be[0][j];	}	for (i = 0; i < BE_TABLE_SIZE; i++) {		crc = crc32table_be[0][i];		for (j = 1; j < BE_TABLE_ROWS; j++) {			crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8);			crc32table_be[j][i] = crc;		}	}} static void output_table(uint32_t (*table)[256], int rows, int len, char *trans){	int i, j; 	for (j = 0 ; j < rows; j++) {		printf("{");		for (i = 0; i < len - 1; i++) {			if (i % ENTRIES_PER_LINE == 0)				printf("\n");			printf("%s(0x%8.8xL), ", trans, table[j][i]);		}		printf("%s(0x%8.8xL)},\n", trans, table[j][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 __cacheline_aligned "		       "crc32table_le[%d][%d] = {",		       LE_TABLE_ROWS, LE_TABLE_SIZE);		output_table(crc32table_le, LE_TABLE_ROWS,			     LE_TABLE_SIZE, "tole");		printf("};\n");	} 	if (CRC_BE_BITS > 1) {		crc32init_be();		printf("static const u32 __cacheline_aligned "		       "crc32table_be[%d][%d] = {",		       BE_TABLE_ROWS, BE_TABLE_SIZE);		output_table(crc32table_be, LE_TABLE_ROWS,			     BE_TABLE_SIZE, "tobe");		printf("};\n");	}	if (CRC_LE_BITS > 1) {		crc32cinit_le();		printf("static const u32 __cacheline_aligned "		       "crc32ctable_le[%d][%d] = {",		       LE_TABLE_ROWS, LE_TABLE_SIZE);		output_table(crc32ctable_le, LE_TABLE_ROWS,			     LE_TABLE_SIZE, "tole");		printf("};\n");	} 	return 0;}