diff options
Diffstat (limited to 'hash.c')
-rw-r--r-- | hash.c | 110 |
1 files changed, 0 insertions, 110 deletions
diff --git a/hash.c b/hash.c deleted file mode 100644 index 749ecfe484..0000000000 --- a/hash.c +++ /dev/null @@ -1,110 +0,0 @@ -/* - * Some generic hashing helpers. - */ -#include "cache.h" -#include "hash.h" - -/* - * Look up a hash entry in the hash table. Return the pointer to - * the existing entry, or the empty slot if none existed. The caller - * can then look at the (*ptr) to see whether it existed or not. - */ -static struct hash_table_entry *lookup_hash_entry(unsigned int hash, const struct hash_table *table) -{ - unsigned int size = table->size, nr = hash % size; - struct hash_table_entry *array = table->array; - - while (array[nr].ptr) { - if (array[nr].hash == hash) - break; - nr++; - if (nr >= size) - nr = 0; - } - return array + nr; -} - - -/* - * Insert a new hash entry pointer into the table. - * - * If that hash entry already existed, return the pointer to - * the existing entry (and the caller can create a list of the - * pointers or do anything else). If it didn't exist, return - * NULL (and the caller knows the pointer has been inserted). - */ -static void **insert_hash_entry(unsigned int hash, void *ptr, struct hash_table *table) -{ - struct hash_table_entry *entry = lookup_hash_entry(hash, table); - - if (!entry->ptr) { - entry->ptr = ptr; - entry->hash = hash; - table->nr++; - return NULL; - } - return &entry->ptr; -} - -static void grow_hash_table(struct hash_table *table) -{ - unsigned int i; - unsigned int old_size = table->size, new_size; - struct hash_table_entry *old_array = table->array, *new_array; - - new_size = alloc_nr(old_size); - new_array = xcalloc(sizeof(struct hash_table_entry), new_size); - table->size = new_size; - table->array = new_array; - table->nr = 0; - for (i = 0; i < old_size; i++) { - unsigned int hash = old_array[i].hash; - void *ptr = old_array[i].ptr; - if (ptr) - insert_hash_entry(hash, ptr, table); - } - free(old_array); -} - -void *lookup_hash(unsigned int hash, const struct hash_table *table) -{ - if (!table->array) - return NULL; - return lookup_hash_entry(hash, table)->ptr; -} - -void **insert_hash(unsigned int hash, void *ptr, struct hash_table *table) -{ - unsigned int nr = table->nr; - if (nr >= table->size/2) - grow_hash_table(table); - return insert_hash_entry(hash, ptr, table); -} - -int for_each_hash(const struct hash_table *table, int (*fn)(void *, void *), void *data) -{ - int sum = 0; - unsigned int i; - unsigned int size = table->size; - struct hash_table_entry *array = table->array; - - for (i = 0; i < size; i++) { - void *ptr = array->ptr; - array++; - if (ptr) { - int val = fn(ptr, data); - if (val < 0) - return val; - sum += val; - } - } - return sum; -} - -void free_hash(struct hash_table *table) -{ - free(table->array); - table->array = NULL; - table->size = 0; - table->nr = 0; -} |