diff options
| -rw-r--r-- | hv.h | 33 |
1 files changed, 25 insertions, 8 deletions
@@ -143,11 +143,19 @@ struct xpvhv { #define PERL_HASH_FUNC_MURMUR3 #define PERL_HASH_FUNC_SIPHASH #define PERL_HASH_FUNC_ONE_AT_A_TIME +#define PERL_HASH_FUNC_ONE_AT_A_TIME_OLD #define PERL_HASH_FUNC_BUZZHASH16 */ -#if !(defined(PERL_HASH_FUNC_SDBM) || defined(PERL_HASH_FUNC_DJB2) || defined(PERL_HASH_FUNC_SUPERFAST) \ - || defined(PERL_HASH_FUNC_MURMUR3) || defined(PERL_HASH_FUNC_ONE_AT_A_TIME) || defined(PERL_HASH_FUNC_BUZZHASH16)) +#if !( 0 \ + || defined(PERL_HASH_FUNC_SDBM) \ + || defined(PERL_HASH_FUNC_DJB2) \ + || defined(PERL_HASH_FUNC_SUPERFAST) \ + || defined(PERL_HASH_FUNC_MURMUR3) \ + || defined(PERL_HASH_FUNC_ONE_AT_A_TIME) \ + || defined(PERL_HASH_FUNC_ONE_AT_A_TIME_OLD) \ + || defined(PERL_HASH_FUNC_BUZZHASH16) \ + ) #define PERL_HASH_FUNC_MURMUR3 #endif @@ -627,11 +635,20 @@ struct xpvhv { (hash) = hash_PeRlHaSh;\ } STMT_END -#elif defined(PERL_HASH_FUNC_ONE_AT_A_TIME) -/* DEFAULT/HISTORIC HASH FUNCTION */ -#define PERL_HASH_FUNC "ONE_AT_A_TIME" +#elif defined(PERL_HASH_FUNC_ONE_AT_A_TIME) || defined(PERL_HASH_FUNC_ONE_AT_A_TIME_OLD) + #define PERL_HASH_SEED_BYTES 4 +#ifdef PERL_HASH_FUNC_ONE_AT_A_TIME +/* new version, add the length to the seed so that adding characters changes the "seed" being used. */ +#define PERL_HASH_FUNC "ONE_AT_A_TIME" +#define MIX_SEED_AND_LEN(seed,len) (seed + len) +#else +/* old version, just use the seed. - not recommended */ +#define PERL_HASH_FUNC "ONE_AT_A_TIME_OLD" +#define MIX_SEED_AND_LEN(seed,len) (seed) +#endif + /* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins * from requirements by Colin Plumb. * (http://burtleburtle.net/bob/hash/doobs.html) */ @@ -639,9 +656,9 @@ struct xpvhv { STMT_START { \ const char * const s_PeRlHaSh_tmp = (str); \ const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \ - I32 i_PeRlHaSh = len; \ - U32 hash_PeRlHaSh = PERL_HASH_SEED_U32 ^ len; \ - while (i_PeRlHaSh--) { \ + const unsigned char *end_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp + (len); \ + U32 hash_PeRlHaSh = MIX_SEED_AND_LEN(PERL_HASH_SEED_U32, len); \ + while (s_PeRlHaSh < end_PeRlHaSh) { \ hash_PeRlHaSh += (U8)*s_PeRlHaSh++; \ hash_PeRlHaSh += (hash_PeRlHaSh << 10); \ hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \ |