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-rw-r--r--hash.c110
1 files changed, 0 insertions, 110 deletions
diff --git a/hash.c b/hash.c
deleted file mode 100644
index 749ecfe..0000000
--- 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;
-}