diff options
Diffstat (limited to 'hashmap.c')
| -rw-r--r-- | hashmap.c | 46 |
1 files changed, 40 insertions, 6 deletions
@@ -50,6 +50,23 @@ unsigned int memihash(const void *buf, size_t len) return hash; } +/* + * Incoporate another chunk of data into a memihash + * computation. + */ +unsigned int memihash_cont(unsigned int hash_seed, const void *buf, size_t len) +{ + unsigned int hash = hash_seed; + unsigned char *ucbuf = (unsigned char *) buf; + while (len--) { + unsigned int c = *ucbuf++; + if (c >= 'a' && c <= 'z') + c -= 'a' - 'A'; + hash = (hash * FNV32_PRIME) ^ c; + } + return hash; +} + #define HASHMAP_INITIAL_SIZE 64 /* grow / shrink by 2^2 */ #define HASHMAP_RESIZE_BITS 2 @@ -78,7 +95,9 @@ static inline int entry_equals(const struct hashmap *map, const struct hashmap_entry *e1, const struct hashmap_entry *e2, const void *keydata) { - return (e1 == e2) || (e1->hash == e2->hash && !map->cmpfn(e1, e2, keydata)); + return (e1 == e2) || + (e1->hash == e2->hash && + !map->cmpfn(map->cmpfn_data, e1, e2, keydata)); } static inline unsigned int bucket(const struct hashmap *map, @@ -87,11 +106,19 @@ static inline unsigned int bucket(const struct hashmap *map, return key->hash & (map->tablesize - 1); } +int hashmap_bucket(const struct hashmap *map, unsigned int hash) +{ + return hash & (map->tablesize - 1); +} + static void rehash(struct hashmap *map, unsigned int newsize) { unsigned int i, oldsize = map->tablesize; struct hashmap_entry **oldtable = map->table; + if (map->disallow_rehash) + return; + alloc_table(map, newsize); for (i = 0; i < oldsize; i++) { struct hashmap_entry *e = oldtable[i]; @@ -115,17 +142,23 @@ static inline struct hashmap_entry **find_entry_ptr(const struct hashmap *map, return e; } -static int always_equal(const void *unused1, const void *unused2, const void *unused3) +static int always_equal(const void *unused_cmp_data, + const void *unused1, + const void *unused2, + const void *unused_keydata) { return 0; } void hashmap_init(struct hashmap *map, hashmap_cmp_fn equals_function, - size_t initial_size) + const void *cmpfn_data, size_t initial_size) { unsigned int size = HASHMAP_INITIAL_SIZE; - map->size = 0; + + memset(map, 0, sizeof(*map)); + map->cmpfn = equals_function ? equals_function : always_equal; + map->cmpfn_data = cmpfn_data; /* calculate initial table size and allocate the table */ initial_size = (unsigned int) ((uint64_t) initial_size * 100 @@ -233,7 +266,8 @@ struct pool_entry { unsigned char data[FLEX_ARRAY]; }; -static int pool_entry_cmp(const struct pool_entry *e1, +static int pool_entry_cmp(const void *unused_cmp_data, + const struct pool_entry *e1, const struct pool_entry *e2, const unsigned char *keydata) { @@ -248,7 +282,7 @@ const void *memintern(const void *data, size_t len) /* initialize string pool hashmap */ if (!map.tablesize) - hashmap_init(&map, (hashmap_cmp_fn) pool_entry_cmp, 0); + hashmap_init(&map, (hashmap_cmp_fn) pool_entry_cmp, NULL, 0); /* lookup interned string in pool */ hashmap_entry_init(&key, memhash(data, len)); |