X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fmemcached_hash.c;h=cca7b5a40ab7e3ec3c6457a7cc0dda4e6c5fbafa;hb=a0c633caf29c00e70b540d5a2cf2cd99207dfdd7;hp=3294a0a6875c16a87e113f35967b7c415b8f4b8a;hpb=002a16ba3cd4638664880a644d73ddf3dc3b2b6b;p=awesomized%2Flibmemcached diff --git a/libmemcached/memcached_hash.c b/libmemcached/memcached_hash.c index 3294a0a6..cca7b5a4 100644 --- a/libmemcached/memcached_hash.c +++ b/libmemcached/memcached_hash.c @@ -8,11 +8,10 @@ static uint32_t FNV_32_INIT= 2166136261UL; static uint32_t FNV_32_PRIME= 16777619; /* Prototypes */ -static uint32_t internal_generate_hash(char *key, size_t key_length); -static uint32_t internal_generate_md5(char *key, size_t key_length); -static uint32_t internal_generate_ketama_md5(char *key, size_t key_length); +static uint32_t internal_generate_hash(const char *key, size_t key_length); +static uint32_t internal_generate_md5(const char *key, size_t key_length); -uint32_t generate_hash(memcached_st *ptr, char *key, size_t key_length) +uint32_t generate_hash(memcached_st *ptr, const char *key, size_t key_length) { uint32_t hash= 1; /* Just here to remove compile warning */ uint32_t x= 0; @@ -81,11 +80,6 @@ uint32_t generate_hash(memcached_st *ptr, char *key, size_t key_length) } } break; - case MEMCACHED_HASH_KETAMA: - { - hash= internal_generate_ketama_md5(key, key_length); - break; - } case MEMCACHED_HASH_HSIEH: { hash= hsieh_hash(key, key_length); @@ -109,7 +103,8 @@ unsigned int dispatch_host(memcached_st *ptr, uint32_t hash) case MEMCACHED_DISTRIBUTION_CONSISTENT: case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA: { - int num= ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER; + uint32_t num= ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER; + WATCHPOINT_ASSERT(ptr->continuum); hash= hash; memcached_continuum_item_st *begin, *end, *left, *right, *middle; @@ -147,7 +142,7 @@ unsigned int dispatch_host(memcached_st *ptr, uint32_t hash) { unsigned int server_key; - server_key= hash % MEMCACHED_WHEEL_SIZE; + server_key= hash % MEMCACHED_STRIDE * ptr->wheel_count; return ptr->wheel[server_key]; } @@ -158,58 +153,15 @@ unsigned int dispatch_host(memcached_st *ptr, uint32_t hash) return hash % ptr->number_of_hosts; } - if (ptr->distribution == MEMCACHED_DISTRIBUTION_MODULA) - { - return hash % ptr->number_of_hosts; - } - else if (ptr->distribution == MEMCACHED_DISTRIBUTION_CONSISTENT) - { - unsigned int server_key; - - server_key= hash % MEMCACHED_WHEEL_SIZE; - - return ptr->wheel[server_key]; - } - else if (ptr->distribution == MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA) - { - int num = ptr->number_of_hosts * MEMCACHED_POINTS_PER_SERVER; - - hash = hash; - memcached_continuum_item_st *begin, *end, *left, *right, *middle; - begin = left = ptr->continuum; - end = right = ptr->continuum + (num - 1); - while(1) - { - middle = left + (right - left) / 2; - if(middle==end) - { - return begin->index; - } - if(middle==begin) - { - return end->index; - } - memcached_continuum_item_st *rmiddle = middle+1; - if(hashvalue && hash>=middle->value) - return middle->index; - - if(middle->value < hash) { - left = middle + 1; - }else if(middle->value > hash) { - right = middle - 1; - } - - if (left>right) - return left->index; - } - } - else - { - WATCHPOINT_ASSERT(0); - } + WATCHPOINT_ASSERT(0); /* We should never reach here */ + return 0; } -unsigned int memcached_generate_hash(memcached_st *ptr, char *key, size_t key_length) +/* + One day make this public, and have it return the actual memcached_server_st + to the calling application. +*/ +uint32_t memcached_generate_hash(memcached_st *ptr, const char *key, size_t key_length) { uint32_t hash= 1; /* Just here to remove compile warning */ @@ -224,9 +176,9 @@ unsigned int memcached_generate_hash(memcached_st *ptr, char *key, size_t key_le return dispatch_host(ptr, hash); } -static uint32_t internal_generate_hash(char *key, size_t key_length) +static uint32_t internal_generate_hash(const char *key, size_t key_length) { - char *ptr= key; + const char *ptr= key; uint32_t value= 0; while (--key_length) @@ -242,19 +194,7 @@ static uint32_t internal_generate_hash(char *key, size_t key_length) return value == 0 ? 1 : value; } -static uint32_t internal_generate_md5(char *key, size_t key_length) -{ - unsigned char results[16]; - - md5_signature((unsigned char*)key, (unsigned int)key_length, results); - - return (uint32_t)(( results[3] << 24 ) - | ( results[2] << 16 ) - | ( results[1] << 8 ) - | results[0] ); -} - -static uint32_t internal_generate_ketama_md5(char *key, size_t key_length) +static uint32_t internal_generate_md5(const char *key, size_t key_length) { unsigned char results[16];