+++ /dev/null
-#include <ccan/hashtable/hashtable.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <assert.h>
-
-/* This means a struct hashtable takes at least 512 bytes / 1k (32/64 bits). */
-#define HASHTABLE_BASE_BITS 7
-
-/* We use 0x1 as deleted marker. */
-#define HASHTABLE_DELETED ((void *)0x1)
-
-/* Number of redundant bits in a pointer. */
-#define PTR_STEAL_BITS 3
-
-static inline uintptr_t get_extra_ptr_bits(const void *p)
-{
- return (uintptr_t)p & (((uintptr_t)1 << PTR_STEAL_BITS)-1);
-}
-
-static inline void *get_raw_ptr(const void *p)
-{
- return (void *)((uintptr_t)p & ~(((uintptr_t)1 << PTR_STEAL_BITS)-1));
-}
-
-static inline void *make_ptr(const void *p, uintptr_t bits)
-{
- return (void *)((uintptr_t)p | bits);
-}
-
-struct hashtable {
- unsigned long (*rehash)(const void *elem, void *priv);
- void *priv;
- unsigned int bits;
- unsigned long elems, max;
- void **table;
-};
-
-static inline bool ptr_is_valid(const void *e)
-{
- return e > HASHTABLE_DELETED;
-}
-
-struct hashtable *hashtable_new(unsigned long (*rehash)(const void *elem,
- void *priv),
- void *priv)
-{
- struct hashtable *ht = malloc(sizeof(struct hashtable));
- if (ht) {
- ht->bits = HASHTABLE_BASE_BITS;
- ht->rehash = rehash;
- ht->priv = priv;
- ht->elems = 0;
- ht->max = (1 << ht->bits) * 3 / 4;
- ht->table = calloc(1 << ht->bits, sizeof(void *));
- if (!ht->table) {
- free(ht);
- ht = NULL;
- }
- }
- return ht;
-}
-
-void hashtable_free(struct hashtable *ht)
-{
- free(ht->table);
- free(ht);
-}
-
-static unsigned long hash_bucket(const struct hashtable *ht,
- unsigned long h, unsigned long *ptrbits)
-{
- *ptrbits = (h >> ht->bits) & (((uintptr_t)1 << PTR_STEAL_BITS)-1);
- return h & ((1 << ht->bits)-1);
-}
-
-/* This does not expand the hash table, that's up to caller. */
-static void ht_add(struct hashtable *ht, const void *new, unsigned long h)
-{
- unsigned long i, h2;
-
- i = hash_bucket(ht, h, &h2);
-
- while (ptr_is_valid(ht->table[i])) {
- i = (i + 1) & ((1 << ht->bits)-1);
- }
- ht->table[i] = make_ptr(new, h2);
-}
-
-static bool double_table(struct hashtable *ht)
-{
- unsigned int i;
- size_t oldnum = (size_t)1 << ht->bits;
- void **oldtable, *e;
-
- oldtable = ht->table;
- ht->table = calloc(1 << (ht->bits+1), sizeof(void *));
- if (!ht->table) {
- ht->table = oldtable;
- return false;
- }
- ht->bits++;
- ht->max *= 2;
-
- for (i = 0; i < oldnum; i++) {
- if (ptr_is_valid(e = oldtable[i])) {
- e = get_raw_ptr(e);
- ht_add(ht, e, ht->rehash(e, ht->priv));
- }
- }
- free(oldtable);
- return true;
-}
-
-bool hashtable_add(struct hashtable *ht, unsigned long hash, const void *p)
-{
- if (ht->elems+1 > ht->max && !double_table(ht))
- return false;
- ht->elems++;
- assert(p);
- assert(((uintptr_t)p & (((uintptr_t)1 << PTR_STEAL_BITS)-1)) == 0);
- ht_add(ht, p, hash);
- return true;
-}
-
-/* Find bucket for an element. */
-static size_t ht_find(struct hashtable *ht,
- unsigned long hash,
- bool (*cmp)(const void *htelem, void *cmpdata),
- void *cmpdata)
-{
- void *e;
- unsigned long i, h2;
-
- i = hash_bucket(ht, hash, &h2);
-
- while ((e = ht->table[i]) != NULL) {
- if (e != HASHTABLE_DELETED
- && h2 == get_extra_ptr_bits(e)
- && cmp(get_raw_ptr(ht->table[i]), cmpdata))
- return i;
- i = (i + 1) & ((1 << ht->bits)-1);
- }
- return (size_t)-1;
-}
-
-
-/* If every one of the following buckets are DELETED (up to the next unused
- one), we can actually mark them all unused. */
-static void delete_run(struct hashtable *ht, unsigned int num)
-{
- unsigned int i, last = num + 1;
-
- while (ht->table[last & ((1 << ht->bits)-1)]) {
- if (ptr_is_valid(ht->table[last & ((1 << ht->bits)-1)]))
- return;
- last++;
- }
- for (i = num; i < last; i++)
- ht->table[i & ((1 << ht->bits)-1)] = NULL;
-}
-
-void *hashtable_find(struct hashtable *ht,
- unsigned long hash,
- bool (*cmp)(const void *htelem, void *cmpdata),
- void *cmpdata)
-{
- size_t i = ht_find(ht, hash, cmp, cmpdata);
- if (i != (size_t)-1)
- return get_raw_ptr(ht->table[i]);
- return NULL;
-}
-
-static bool ptr_cmp(const void *htelem, void *cmpdata)
-{
- return htelem == cmpdata;
-}
-
-bool hashtable_del(struct hashtable *ht, unsigned long hash, const void *p)
-{
- size_t i = ht_find(ht, hash, ptr_cmp, (void *)p);
- if (i == (size_t)-1)
- return false;
-
- ht->elems--;
- ht->table[i] = HASHTABLE_DELETED;
- delete_run(ht, i);
- return true;
-}
-
-void _hashtable_traverse(struct hashtable *ht,
- bool (*cb)(void *p, void *cbarg),
- void *cbarg)
-{
- size_t i;
-
- for (i = 0; i < (1 << ht->bits); i++) {
- if (ptr_is_valid(ht->table[i]))
- if (cb(get_raw_ptr(ht->table[i]), cbarg))
- return;
- }
-}