Merge branch '2.6'

src/hashtable.c

@@ -5,8 +5,17 @@
  * it under the terms of the MIT license. See LICENSE for details.
  */
 
+#if HAVE_CONFIG_H
+#include <jansson_private_config.h>
+#endif
+
 #include <stdlib.h>
 #include <string.h>
+
+#if HAVE_STDINT_H
+#include <stdint.h>
+#endif
+
 #include <jansson_config.h>   /* for JSON_INLINE */
 #include "jansson_private.h"  /* for container_of() */
 #include "hashtable.h"
@@ -15,24 +24,13 @@ typedef struct hashtable_list list_t;
 typedef struct hashtable_pair pair_t;
 typedef struct hashtable_bucket bucket_t;
 
+extern volatile uint32_t hashtable_seed;
+
+/* Implementation of the hash function */
+#include "lookup3.h"
+
 #define list_to_pair(list_)  container_of(list_, pair_t, list)
-
-/* From http://www.cse.yorku.ca/~oz/hash.html */
-static size_t hash_str(const void *ptr)
-{
-    const char *str = (const char *)ptr;
-
-    size_t hash = 5381;
-    size_t c;
-
-    while((c = (size_t)*str))
-    {
-        hash = ((hash << 5) + hash) + c;
-        str++;
-    }
-
-    return hash;
-}
+#define hash_str(key)        ((size_t)hashlittle((key), strlen(key), hashtable_seed))
 
 static JSON_INLINE void list_init(list_t *list)
 {
@@ -74,19 +72,6 @@ static void insert_to_bucket(hashtable_t *hashtable, bucket_t *bucket,
     }
 }
 
-static const size_t primes[] = {
-    5, 13, 23, 53, 97, 193, 389, 769, 1543, 3079, 6151, 12289, 24593,
-    49157, 98317, 196613, 393241, 786433, 1572869, 3145739, 6291469,
-    12582917, 25165843, 50331653, 100663319, 201326611, 402653189,
-    805306457, 1610612741
-};
-
-static JSON_INLINE size_t num_buckets(hashtable_t *hashtable)
-{
-    return primes[hashtable->num_buckets];
-}
-
-
 static pair_t *hashtable_find_pair(hashtable_t *hashtable, bucket_t *bucket,
                                    const char *key, size_t hash)
 {
@@ -120,7 +105,7 @@ static int hashtable_do_del(hashtable_t *hashtable,
     bucket_t *bucket;
     size_t index;
 
-    index = hash % num_buckets(hashtable);
+    index = hash & hashmask(hashtable->order);
     bucket = &hashtable->buckets[index];
 
     pair = hashtable_find_pair(hashtable, bucket, key, hash);
@@ -167,14 +152,14 @@ static int hashtable_do_rehash(hashtable_t *hashtable)
 
     jsonp_free(hashtable->buckets);
 
-    hashtable->num_buckets++;
-    new_size = num_buckets(hashtable);
+    hashtable->order++;
+    new_size = hashsize(hashtable->order);
 
     hashtable->buckets = jsonp_malloc(new_size * sizeof(bucket_t));
     if(!hashtable->buckets)
         return -1;
 
-    for(i = 0; i < num_buckets(hashtable); i++)
+    for(i = 0; i < hashsize(hashtable->order); i++)
     {
         hashtable->buckets[i].first = hashtable->buckets[i].last =
             &hashtable->list;
@@ -199,14 +184,14 @@ int hashtable_init(hashtable_t *hashtable)
     size_t i;
 
     hashtable->size = 0;
-    hashtable->num_buckets = 0;  /* index to primes[] */
-    hashtable->buckets = jsonp_malloc(num_buckets(hashtable) * sizeof(bucket_t));
+    hashtable->order = 3;
+    hashtable->buckets = jsonp_malloc(hashsize(hashtable->order) * sizeof(bucket_t));
     if(!hashtable->buckets)
         return -1;
 
     list_init(&hashtable->list);
 
-    for(i = 0; i < num_buckets(hashtable); i++)
+    for(i = 0; i < hashsize(hashtable->order); i++)
     {
         hashtable->buckets[i].first = hashtable->buckets[i].last =
             &hashtable->list;
@@ -230,12 +215,12 @@ int hashtable_set(hashtable_t *hashtable,
     size_t hash, index;
 
     /* rehash if the load ratio exceeds 1 */
-    if(hashtable->size >= num_buckets(hashtable))
+    if(hashtable->size >= hashsize(hashtable->order))
         if(hashtable_do_rehash(hashtable))
             return -1;
 
     hash = hash_str(key);
-    index = hash % num_buckets(hashtable);
+    index = hash & hashmask(hashtable->order);
     bucket = &hashtable->buckets[index];
     pair = hashtable_find_pair(hashtable, bucket, key, hash);
 
@@ -280,7 +265,7 @@ void *hashtable_get(hashtable_t *hashtable, const char *key)
     bucket_t *bucket;
 
     hash = hash_str(key);
-    bucket = &hashtable->buckets[hash % num_buckets(hashtable)];
+    bucket = &hashtable->buckets[hash & hashmask(hashtable->order)];
 
     pair = hashtable_find_pair(hashtable, bucket, key, hash);
     if(!pair)
@@ -301,7 +286,7 @@ void hashtable_clear(hashtable_t *hashtable)
 
     hashtable_do_clear(hashtable);
 
-    for(i = 0; i < num_buckets(hashtable); i++)
+    for(i = 0; i < hashsize(hashtable->order); i++)
     {
         hashtable->buckets[i].first = hashtable->buckets[i].last =
             &hashtable->list;
@@ -323,7 +308,7 @@ void *hashtable_iter_at(hashtable_t *hashtable, const char *key)
     bucket_t *bucket;
 
     hash = hash_str(key);
-    bucket = &hashtable->buckets[hash % num_buckets(hashtable)];
+    bucket = &hashtable->buckets[hash & hashmask(hashtable->order)];
 
     pair = hashtable_find_pair(hashtable, bucket, key, hash);
     if(!pair)