X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fhash.c;h=ce47a44833ff4e5b5deaf7f28111974df405d714;hb=2df9084da8c73d8813f8740e88cd70fe63dd742c;hp=7683761ee28eb940a831de1403f44429a2eb6f1a;hpb=965bde2b42f5ef2dd7b55b6b4b74822e7cfaa1de;p=m6w6%2Flibmemcached

diff --git a/libmemcached/hash.c b/libmemcached/hash.c
index 7683761e..ce47a448 100644
--- a/libmemcached/hash.c
+++ b/libmemcached/hash.c
@@ -1,127 +1,28 @@
-#include "common.h"
-
+/* LibMemcached
+ * Copyright (C) 2006-2010 Brian Aker
+ * All rights reserved.
+ *
+ * Use and distribution licensed under the BSD license.  See
+ * the COPYING file in the parent directory for full text.
+ *
+ * Summary: 
+ *
+ */
 
-/* Defines */
-static uint64_t FNV_64_INIT= UINT64_C(0xcbf29ce484222325);
-static uint64_t FNV_64_PRIME= UINT64_C(0x100000001b3);
-
-static uint32_t FNV_32_INIT= 2166136261UL;
-static uint32_t FNV_32_PRIME= 16777619;
+#include "common.h"
 
-/* Prototypes */
-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 memcached_generate_hash_value(const char *key, size_t key_length, memcached_hash_t hash_algorithm)
 {
-  uint32_t hash= 1; /* Just here to remove compile warning */
-  uint32_t x= 0;
-
-  switch (hash_algorithm)
-  {
-  case MEMCACHED_HASH_DEFAULT:
-    hash= internal_generate_hash(key, key_length);
-    break;
-  case MEMCACHED_HASH_MD5:
-    hash= internal_generate_md5(key, key_length);
-    break;
-  case MEMCACHED_HASH_CRC:
-    hash= ((hash_crc32(key, key_length) >> 16) & 0x7fff);
-    if (hash == 0)
-      hash= 1;
-    break;
-    /* FNV hash'es lifted from Dustin Sallings work */
-  case MEMCACHED_HASH_FNV1_64:
-    {
-      /* Thanks to pierre@demartines.com for the pointer */
-      uint64_t temp_hash;
-
-      temp_hash= FNV_64_INIT;
-      for (x= 0; x < key_length; x++)
-      {
-        temp_hash *= FNV_64_PRIME;
-        temp_hash ^= (uint64_t)key[x];
-      }
-      hash= (uint32_t)temp_hash;
-    }
-    break;
-  case MEMCACHED_HASH_FNV1A_64:
-    {
-      hash= (uint32_t) FNV_64_INIT;
-      for (x= 0; x < key_length; x++)
-      {
-        uint32_t val= (uint32_t)key[x];
-        hash ^= val;
-        hash *= (uint32_t) FNV_64_PRIME;
-      }
-    }
-    break;
-  case MEMCACHED_HASH_FNV1_32:
-    {
-      hash= FNV_32_INIT;
-      for (x= 0; x < key_length; x++)
-      {
-        uint32_t val= (uint32_t)key[x];
-        hash *= FNV_32_PRIME;
-        hash ^= val;
-      }
-    }
-    break;
-  case MEMCACHED_HASH_FNV1A_32:
-    {
-      hash= FNV_32_INIT;
-      for (x= 0; x < key_length; x++)
-      {
-        uint32_t val= (uint32_t)key[x];
-        hash ^= val;
-        hash *= FNV_32_PRIME;
-      }
-    }
-    break;
-    case MEMCACHED_HASH_HSIEH:
-    {
-#ifdef HAVE_HSIEH_HASH
-      hash= hsieh_hash(key, key_length);
-#endif
-      break;
-    }
-    case MEMCACHED_HASH_MURMUR:
-    {
-      hash= murmur_hash(key, key_length);
-      break;
-    }
-    case MEMCACHED_HASH_JENKINS:
-    {
-      hash= jenkins_hash(key, key_length, 13);
-      break;
-    }
-    case MEMCACHED_HASH_MAX:
-    default:
-    {
-      WATCHPOINT_ASSERT(0);
-      break;
-    }
-  }
-
-  return hash;
+  return libhashkit_digest(key, key_length, (hashkit_hash_algorithm_t)hash_algorithm);
 }
 
-uint32_t generate_hash(memcached_st *ptr, const char *key, size_t key_length)
+static inline uint32_t generate_hash(const memcached_st *ptr, const char *key, size_t key_length)
 {
-  uint32_t hash= 1; /* Just here to remove compile warning */
-
-
-  WATCHPOINT_ASSERT(ptr->number_of_hosts);
-
-  if (ptr->number_of_hosts == 1)
-    return 0;
-
-  hash= memcached_generate_hash_value(key, key_length, ptr->hash);
-  WATCHPOINT_ASSERT(hash);
-  return hash;
+  return hashkit_digest(&ptr->hashkit, key, key_length);
 }
 
-static uint32_t dispatch_host(memcached_st *ptr, uint32_t hash)
+static uint32_t dispatch_host(const memcached_st *ptr, uint32_t hash)
 {
   switch (ptr->distribution)
   {
@@ -150,50 +51,49 @@ static uint32_t dispatch_host(memcached_st *ptr, uint32_t hash)
       return right->index;
     }
   case MEMCACHED_DISTRIBUTION_MODULA:
-    return hash % ptr->number_of_hosts;
+    return hash % memcached_server_count(ptr);
   case MEMCACHED_DISTRIBUTION_RANDOM:
-    return (uint32_t) random() % ptr->number_of_hosts;
+    return (uint32_t) random() % memcached_server_count(ptr);
   case MEMCACHED_DISTRIBUTION_CONSISTENT_MAX:
   default:
     WATCHPOINT_ASSERT(0); /* We have added a distribution without extending the logic */
-    return hash % ptr->number_of_hosts;
+    return hash % memcached_server_count(ptr);
   }
   /* NOTREACHED */
 }
 
 /*
-  One day make this public, and have it return the actual memcached_server_st
-  to the calling application.
+  One version is public and will not modify the distribution hash, the other will.
 */
-uint32_t memcached_generate_hash(memcached_st *ptr, const char *key, size_t key_length)
+static inline uint32_t _generate_hash_wrapper(const memcached_st *ptr, const char *key, size_t key_length)
 {
-  uint32_t hash= 1; /* Just here to remove compile warning */
+  WATCHPOINT_ASSERT(memcached_server_count(ptr));
 
-  WATCHPOINT_ASSERT(ptr->number_of_hosts);
-
-  if (ptr->number_of_hosts == 1)
+  if (memcached_server_count(ptr) == 1)
     return 0;
 
   if (ptr->flags.hash_with_prefix_key)
   {
-    size_t temp_length= ptr->prefix_key_length + key_length;
+    size_t temp_length= memcached_array_size(ptr->prefix_key) + key_length;
     char temp[temp_length];
 
     if (temp_length > MEMCACHED_MAX_KEY -1)
       return 0;
 
-    strncpy(temp, ptr->prefix_key, ptr->prefix_key_length);
-    strncpy(temp + ptr->prefix_key_length, key, key_length);
-    hash= generate_hash(ptr, temp, temp_length);
+    strncpy(temp, memcached_array_string(ptr->prefix_key), memcached_array_size(ptr->prefix_key));
+    strncpy(temp + memcached_array_size(ptr->prefix_key), key, key_length);
+
+    return generate_hash(ptr, temp, temp_length);
   }
   else
   {
-    hash= generate_hash(ptr, key, key_length);
+    return generate_hash(ptr, key, key_length);
   }
+}
 
-  WATCHPOINT_ASSERT(hash);
-
-  if (memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_AUTO_EJECT_HOSTS) && ptr->next_distribution_rebuild)
+static inline void _regen_for_auto_eject(memcached_st *ptr)
+{
+  if (_is_auto_eject_host(ptr) && ptr->next_distribution_rebuild)
   {
     struct timeval now;
 
@@ -203,37 +103,56 @@ uint32_t memcached_generate_hash(memcached_st *ptr, const char *key, size_t key_
       run_distribution(ptr);
     }
   }
+}
 
-  return dispatch_host(ptr, hash);
+void memcached_autoeject(memcached_st *ptr)
+{
+  _regen_for_auto_eject(ptr);
 }
 
-static uint32_t internal_generate_hash(const char *key, size_t key_length)
+uint32_t memcached_generate_hash_with_redistribution(memcached_st *ptr, const char *key, size_t key_length)
 {
-  const char *ptr= key;
-  uint32_t value= 0;
+  uint32_t hash= _generate_hash_wrapper(ptr, key, key_length);
 
-  while (key_length--)
-  {
-    uint32_t val= (uint32_t) *ptr++;
-    value += val;
-    value += (value << 10);
-    value ^= (value >> 6);
-  }
-  value += (value << 3);
-  value ^= (value >> 11);
-  value += (value << 15);
+  _regen_for_auto_eject(ptr);
 
-  return value == 0 ? 1 : (uint32_t) value;
+  return dispatch_host(ptr, hash);
 }
 
-static uint32_t internal_generate_md5(const char *key, size_t key_length)
+uint32_t memcached_generate_hash(const memcached_st *ptr, const char *key, size_t key_length)
 {
-  unsigned char results[16];
+  return dispatch_host(ptr, _generate_hash_wrapper(ptr, key, key_length));
+}
 
-  md5_signature((unsigned char*)key, (unsigned int)key_length, results);
+const hashkit_st *memcached_get_hashkit(const memcached_st *ptr)
+{
+  return &ptr->hashkit;
+}
 
-  return ((uint32_t) (results[3] & 0xFF) << 24)
-    | ((uint32_t) (results[2] & 0xFF) << 16)
-    | ((uint32_t) (results[1] & 0xFF) << 8)
-    | (results[0] & 0xFF);
+memcached_return_t memcached_set_hashkit(memcached_st *self, hashkit_st *hashk)
+{
+  hashkit_free(&self->hashkit);
+  hashkit_clone(&self->hashkit, hashk);
+
+  return MEMCACHED_SUCCESS;
+}
+
+const char * libmemcached_string_hash(memcached_hash_t type)
+{
+  switch (type)
+  {
+  case MEMCACHED_HASH_DEFAULT: return "MEMCACHED_HASH_DEFAULT";
+  case MEMCACHED_HASH_MD5: return "MEMCACHED_HASH_MD5";
+  case MEMCACHED_HASH_CRC: return "MEMCACHED_HASH_CRC";
+  case MEMCACHED_HASH_FNV1_64: return "MEMCACHED_HASH_FNV1_64";
+  case MEMCACHED_HASH_FNV1A_64: return "MEMCACHED_HASH_FNV1A_64";
+  case MEMCACHED_HASH_FNV1_32: return "MEMCACHED_HASH_FNV1_32";
+  case MEMCACHED_HASH_FNV1A_32: return "MEMCACHED_HASH_FNV1A_32";
+  case MEMCACHED_HASH_HSIEH: return "MEMCACHED_HASH_HSIEH";
+  case MEMCACHED_HASH_MURMUR: return "MEMCACHED_HASH_MURMUR";
+  case MEMCACHED_HASH_JENKINS: return "MEMCACHED_HASH_JENKINS";
+  case MEMCACHED_HASH_CUSTOM: return "MEMCACHED_HASH_CUSTOM";
+  default:
+  case MEMCACHED_HASH_MAX: return "INVALID memcached_hash_t";
+  }
 }