Annotation of embedaddon/php/ext/hash/hash_fnv.c, revision 1.1
1.1 ! misho 1: /*
! 2: +----------------------------------------------------------------------+
! 3: | PHP Version 5 |
! 4: +----------------------------------------------------------------------+
! 5: | Copyright (c) 1997-2012 The PHP Group |
! 6: +----------------------------------------------------------------------+
! 7: | This source file is subject to version 3.01 of the PHP license, |
! 8: | that is bundled with this package in the file LICENSE, and is |
! 9: | available through the world-wide-web at the following url: |
! 10: | http://www.php.net/license/3_01.txt |
! 11: | If you did not receive a copy of the PHP license and are unable to |
! 12: | obtain it through the world-wide-web, please send a note to |
! 13: | license@php.net so we can mail you a copy immediately. |
! 14: +----------------------------------------------------------------------+
! 15: | Author: Michael Maclean <mgdm@php.net> |
! 16: +----------------------------------------------------------------------+
! 17: */
! 18:
! 19: /* $Id$ */
! 20:
! 21: /* Based on the public domain algorithm found at
! 22: http://www.isthe.com/chongo/tech/comp/fnv/index.html */
! 23:
! 24: #include "php_hash.h"
! 25: #include "php_hash_fnv.h"
! 26:
! 27: const php_hash_ops php_hash_fnv132_ops = {
! 28: (php_hash_init_func_t) PHP_FNV132Init,
! 29: (php_hash_update_func_t) PHP_FNV132Update,
! 30: (php_hash_final_func_t) PHP_FNV132Final,
! 31: (php_hash_copy_func_t) php_hash_copy,
! 32: 4,
! 33: 4,
! 34: sizeof(PHP_FNV132_CTX)
! 35: };
! 36:
! 37: const php_hash_ops php_hash_fnv1a32_ops = {
! 38: (php_hash_init_func_t) PHP_FNV132Init,
! 39: (php_hash_update_func_t) PHP_FNV1a32Update,
! 40: (php_hash_final_func_t) PHP_FNV132Final,
! 41: (php_hash_copy_func_t) php_hash_copy,
! 42: 4,
! 43: 4,
! 44: sizeof(PHP_FNV132_CTX)
! 45: };
! 46:
! 47: const php_hash_ops php_hash_fnv164_ops = {
! 48: (php_hash_init_func_t) PHP_FNV164Init,
! 49: (php_hash_update_func_t) PHP_FNV164Update,
! 50: (php_hash_final_func_t) PHP_FNV164Final,
! 51: (php_hash_copy_func_t) php_hash_copy,
! 52: 8,
! 53: 4,
! 54: sizeof(PHP_FNV164_CTX)
! 55: };
! 56:
! 57: const php_hash_ops php_hash_fnv1a64_ops = {
! 58: (php_hash_init_func_t) PHP_FNV164Init,
! 59: (php_hash_update_func_t) PHP_FNV1a64Update,
! 60: (php_hash_final_func_t) PHP_FNV164Final,
! 61: (php_hash_copy_func_t) php_hash_copy,
! 62: 8,
! 63: 4,
! 64: sizeof(PHP_FNV164_CTX)
! 65: };
! 66:
! 67: /* {{{ PHP_FNV132Init
! 68: * 32-bit FNV-1 hash initialisation
! 69: */
! 70: PHP_HASH_API void PHP_FNV132Init(PHP_FNV132_CTX *context)
! 71: {
! 72: context->state = PHP_FNV1_32_INIT;
! 73: }
! 74: /* }}} */
! 75:
! 76: PHP_HASH_API void PHP_FNV132Update(PHP_FNV132_CTX *context, const unsigned char *input,
! 77: unsigned int inputLen)
! 78: {
! 79: context->state = fnv_32_buf((void *)input, inputLen, context->state, 0);
! 80: }
! 81:
! 82: PHP_HASH_API void PHP_FNV1a32Update(PHP_FNV132_CTX *context, const unsigned char *input,
! 83: unsigned int inputLen)
! 84: {
! 85: context->state = fnv_32_buf((void *)input, inputLen, context->state, 1);
! 86: }
! 87:
! 88: PHP_HASH_API void PHP_FNV132Final(unsigned char digest[4], PHP_FNV132_CTX * context)
! 89: {
! 90: #ifdef WORDS_BIGENDIAN
! 91: memcpy(digest, &context->state, 4);
! 92: #else
! 93: int i = 0;
! 94: unsigned char *c = (unsigned char *) &context->state;
! 95:
! 96: for (i = 0; i < 4; i++) {
! 97: digest[i] = c[3 - i];
! 98: }
! 99: #endif
! 100: }
! 101:
! 102: /* {{{ PHP_FNV164Init
! 103: * 64-bit FNV-1 hash initialisation
! 104: */
! 105: PHP_HASH_API void PHP_FNV164Init(PHP_FNV164_CTX *context)
! 106: {
! 107: context->state = PHP_FNV1_64_INIT;
! 108: }
! 109: /* }}} */
! 110:
! 111: PHP_HASH_API void PHP_FNV164Update(PHP_FNV164_CTX *context, const unsigned char *input,
! 112: unsigned int inputLen)
! 113: {
! 114: context->state = fnv_64_buf((void *)input, inputLen, context->state, 0);
! 115: }
! 116:
! 117: PHP_HASH_API void PHP_FNV1a64Update(PHP_FNV164_CTX *context, const unsigned char *input,
! 118: unsigned int inputLen)
! 119: {
! 120: context->state = fnv_64_buf((void *)input, inputLen, context->state, 1);
! 121: }
! 122:
! 123: PHP_HASH_API void PHP_FNV164Final(unsigned char digest[8], PHP_FNV164_CTX * context)
! 124: {
! 125: #ifdef WORDS_BIGENDIAN
! 126: memcpy(digest, &context->state, 8);
! 127: #else
! 128: int i = 0;
! 129: unsigned char *c = (unsigned char *) &context->state;
! 130:
! 131: for (i = 0; i < 8; i++) {
! 132: digest[i] = c[7 - i];
! 133: }
! 134: #endif
! 135: }
! 136:
! 137:
! 138: /*
! 139: * fnv_32_buf - perform a 32 bit Fowler/Noll/Vo hash on a buffer
! 140: *
! 141: * input:
! 142: * buf - start of buffer to hash
! 143: * len - length of buffer in octets
! 144: * hval - previous hash value or 0 if first call
! 145: * alternate - if > 0 use the alternate version
! 146: *
! 147: * returns:
! 148: * 32 bit hash as a static hash type
! 149: */
! 150: static php_hash_uint32
! 151: fnv_32_buf(void *buf, size_t len, php_hash_uint32 hval, int alternate)
! 152: {
! 153: unsigned char *bp = (unsigned char *)buf; /* start of buffer */
! 154: unsigned char *be = bp + len; /* beyond end of buffer */
! 155:
! 156: /*
! 157: * FNV-1 hash each octet in the buffer
! 158: */
! 159: while (bp < be) {
! 160:
! 161: if (alternate == 0) {
! 162: /* multiply by the 32 bit FNV magic prime mod 2^32 */
! 163: hval *= PHP_FNV_32_PRIME;
! 164:
! 165: /* xor the bottom with the current octet */
! 166: hval ^= (php_hash_uint32)*bp++;
! 167: } else {
! 168: /* xor the bottom with the current octet */
! 169: hval ^= (php_hash_uint32)*bp++;
! 170:
! 171: /* multiply by the 32 bit FNV magic prime mod 2^32 */
! 172: hval *= PHP_FNV_32_PRIME;
! 173: }
! 174: }
! 175:
! 176: /* return our new hash value */
! 177: return hval;
! 178: }
! 179:
! 180: /*
! 181: * fnv_64_buf - perform a 64 bit Fowler/Noll/Vo hash on a buffer
! 182: *
! 183: * input:
! 184: * buf - start of buffer to hash
! 185: * len - length of buffer in octets
! 186: * hval - previous hash value or 0 if first call
! 187: * alternate - if > 0 use the alternate version
! 188: *
! 189: * returns:
! 190: * 64 bit hash as a static hash type
! 191: */
! 192: static php_hash_uint64
! 193: fnv_64_buf(void *buf, size_t len, php_hash_uint64 hval, int alternate)
! 194: {
! 195: unsigned char *bp = (unsigned char *)buf; /* start of buffer */
! 196: unsigned char *be = bp + len; /* beyond end of buffer */
! 197:
! 198: /*
! 199: * FNV-1 hash each octet of the buffer
! 200: */
! 201: while (bp < be) {
! 202:
! 203: if (alternate == 0) {
! 204: /* multiply by the 64 bit FNV magic prime mod 2^64 */
! 205: hval *= PHP_FNV_64_PRIME;
! 206:
! 207: /* xor the bottom with the current octet */
! 208: hval ^= (php_hash_uint64)*bp++;
! 209: } else {
! 210: /* xor the bottom with the current octet */
! 211: hval ^= (php_hash_uint64)*bp++;
! 212:
! 213: /* multiply by the 64 bit FNV magic prime mod 2^64 */
! 214: hval *= PHP_FNV_64_PRIME;
! 215: }
! 216: }
! 217:
! 218: /* return our new hash value */
! 219: return hval;
! 220: }
! 221:
! 222: /*
! 223: * Local variables:
! 224: * tab-width: 4
! 225: * c-basic-offset: 4
! 226: * End:
! 227: * vim600: noet sw=4 ts=4 fdm=marker
! 228: * vim<600: noet sw=4 ts=4
! 229: */
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>
![[BACK]](/icons/cvsweb/back.gif){kind=icon}
Return to hash_fnv.c CVS log ![[TXT]](/icons/cvsweb/text.gif){kind=icon}
![[DIR]](/icons/cvsweb/dir.gif){kind=icon}
Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / php / ext / hash