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-rw-r--r--trunk/main/hashtab.c805
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diff --git a/trunk/main/hashtab.c b/trunk/main/hashtab.c
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+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2007, Digium, Inc.
+ *
+ * Steve Murphy <murf@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+/*! \file
+ *
+ * \brief code to implement generic hash tables
+ *
+ * \author Steve Murphy <murf@digium.com>
+ */
+
+#include "asterisk.h"
+
+ASTERISK_FILE_VERSION(__FILE__, "$Revision")
+
+#include <ctype.h>
+
+#include "asterisk/lock.h"
+#include "asterisk/frame.h"
+#include "asterisk/channel.h"
+#include "asterisk/cli.h"
+#include "asterisk/term.h"
+#include "asterisk/utils.h"
+#include "asterisk/threadstorage.h"
+#include "asterisk/linkedlists.h"
+#include "asterisk/hashtab.h"
+
+static void ast_hashtab_resize( struct ast_hashtab *tab);
+static void *ast_hashtab_lookup_internal(struct ast_hashtab *tab, const void *obj, unsigned int h);
+
+/* some standard, default routines for general use */
+
+int ast_hashtab_compare_strings(const void *a, const void *b)
+{
+ return strcmp((char*)a,(char*)b);
+}
+
+int ast_hashtab_compare_strings_nocase(const void *a, const void *b)
+{
+ return strcasecmp((const char*)a,(const char*)b);
+}
+
+int ast_hashtab_compare_ints(const void *a, const void *b)
+{
+ int ai = *((int *) a);
+ int bi = *((int *) b);
+
+ if (ai < bi)
+ return -1;
+
+ return !(ai == bi);
+}
+
+int ast_hashtab_compare_shorts(const void *a, const void *b)
+{
+ short as = *((short *) a);
+ short bs = *((short *) b);
+
+ if (as < bs)
+ return -1;
+
+ return !(as == bs);
+}
+
+int ast_hashtab_resize_java(struct ast_hashtab *tab)
+{
+ double loadfactor = (double) tab->hash_tab_elements / (double) tab->hash_tab_size;
+
+ return (loadfactor > 0.75);
+}
+
+int ast_hashtab_resize_tight(struct ast_hashtab *tab)
+{
+ return (tab->hash_tab_elements > tab->hash_tab_size); /* this is quicker than division */
+}
+
+int ast_hashtab_resize_none(struct ast_hashtab *tab) /* always return 0 -- no resizing */
+{
+ return 0;
+}
+
+int ast_is_prime(int num)
+{
+ int tnum, limit;
+
+ if (!(num & 0x1)) /* even number -- not prime */
+ return 0;
+
+ /* Loop through ODD numbers starting with 3 */
+
+ tnum = 3;
+ limit = num;
+ while (tnum < limit) {
+ if (!(num % tnum))
+ return 0;
+
+ /* really, we only need to check sqrt(num) numbers */
+ limit = num / tnum;
+
+ /* we only check odd numbers */
+ tnum = tnum + 2;
+ }
+
+ /* if we made it through the loop, the number is a prime */
+
+ return 1;
+}
+
+int ast_hashtab_newsize_java(struct ast_hashtab *tab)
+{
+ int i = (tab->hash_tab_size << 1); /* multiply by two */
+
+ while (!ast_is_prime(i))
+ i++;
+
+ return i;
+}
+
+int ast_hashtab_newsize_tight(struct ast_hashtab *tab)
+{
+ int x = (tab->hash_tab_size << 1);
+ int i = (tab->hash_tab_size + x);
+
+ while (!ast_is_prime(i))
+ i++;
+
+ return i;
+}
+
+int ast_hashtab_newsize_none(struct ast_hashtab *tab) /* always return current size -- no resizing */
+{
+ return tab->hash_tab_size;
+}
+
+unsigned int ast_hashtab_hash_string(const void *obj)
+{
+ unsigned char *str = (unsigned char *) obj;
+ unsigned int total;
+
+ for (total = 0; *str; str++)
+ {
+ unsigned int tmp = total;
+ total <<= 1; /* multiply by 2 */
+ total += tmp; /* multiply by 3 */
+ total <<= 2; /* multiply by 12 */
+ total += tmp; /* multiply by 13 */
+
+ total += ((unsigned int)(*str));
+ }
+ return total;
+}
+
+unsigned int ast_hashtab_hash_string_sax(const void *obj) /* from Josh */
+{
+ unsigned char *str = (unsigned char *) obj;
+ unsigned int total = 0, c = 0;
+
+ while ((c = *str++))
+ total ^= (total << 5) + (total >> 2) + (total << 10) + c;
+
+ return total;
+}
+
+unsigned int ast_hashtab_hash_string_nocase(const void *obj)
+{
+ unsigned char *str = (unsigned char*)obj;
+ unsigned int total;
+
+ for (total = 0; *str; str++) {
+ unsigned int tmp = total;
+ unsigned int charval = toupper(*str);
+
+ /* hopefully, the following is faster than multiplication by 7 */
+ /* why do I go to this bother? A good compiler will do this
+ anyway, if I say total *= 13 */
+ /* BTW, tried *= 7, and it doesn't do as well in spreading things around! */
+ total <<= 1; /* multiply by 2 */
+ total += tmp; /* multiply by 3 */
+ total <<= 2; /* multiply by 12 */
+ total += tmp; /* multiply by 13 */
+
+ total += (charval);
+ }
+
+ return total;
+}
+
+unsigned int ast_hashtab_hash_int(const int x)
+{
+ return x;
+}
+
+unsigned int ast_hashtab_hash_short(const short x)
+{
+ /* hmmmm.... modulus is best < 65535 !! */
+ return x;
+}
+
+struct ast_hashtab *ast_hashtab_create(int initial_buckets,
+ int (*compare)(const void *a, const void *b),
+ int (*resize)(struct ast_hashtab *),
+ int (*newsize)(struct ast_hashtab *tab),
+ unsigned int (*hash)(const void *obj),
+ int do_locking)
+{
+ struct ast_hashtab *ht;
+
+ if (!(ht = ast_calloc(1, sizeof(*ht))))
+ return NULL;
+
+ while (!ast_is_prime(initial_buckets)) /* make sure this is prime */
+ initial_buckets++;
+
+ if (!(ht->array = ast_calloc(initial_buckets, sizeof(*(ht->array))))) {
+ free(ht);
+ return NULL;
+ }
+
+ ht->hash_tab_size = initial_buckets;
+ ht->compare = compare;
+ ht->resize = resize;
+ ht->newsize = newsize;
+ ht->hash = hash;
+ ht->do_locking = do_locking;
+
+ if (do_locking)
+ ast_rwlock_init(&ht->lock);
+
+ if (!ht->resize)
+ ht->resize = ast_hashtab_resize_java;
+
+ if (!ht->newsize)
+ ht->newsize = ast_hashtab_newsize_java;
+
+ return ht;
+}
+
+struct ast_hashtab *ast_hashtab_dup(struct ast_hashtab *tab, void *(*obj_dup_func)(const void *obj))
+{
+ struct ast_hashtab *ht;
+ unsigned int i;
+
+ if (!(ht = ast_calloc(1, sizeof(*ht))))
+ return NULL;
+
+ if (!(ht->array = ast_calloc(tab->hash_tab_size, sizeof(*(ht->array))))) {
+ free(ht);
+ return NULL;
+ }
+
+ ht->hash_tab_size = tab->hash_tab_size;
+ ht->compare = tab->compare;
+ ht->resize = tab->resize;
+ ht->newsize = tab->newsize;
+ ht->hash = tab->hash;
+ ht->do_locking = tab->do_locking;
+
+ if (ht->do_locking)
+ ast_rwlock_init(&ht->lock);
+
+ /* now, dup the objects in the buckets and get them into the table */
+ /* the fast way is to use the existing array index, and not have to hash
+ the objects again */
+ for (i = 0; i < ht->hash_tab_size; i++) {
+ struct ast_hashtab_bucket *b = tab->array[i];
+ while (b) {
+ void *newobj = (*obj_dup_func)(b->object);
+ if (newobj)
+ ast_hashtab_insert_immediate_bucket(ht, newobj, i);
+ b = b->next;
+ }
+ }
+
+ return ht;
+}
+
+static void tlist_del_item(struct ast_hashtab_bucket **head, struct ast_hashtab_bucket *item)
+{
+ /* item had better be in the list! or suffer the weirdness that occurs, later! */
+ if (*head == item) { /* first item in the list */
+ *head = item->tnext;
+ if (item->tnext)
+ item->tnext->tprev = NULL;
+ } else {
+ /* short circuit stuff */
+ item->tprev->tnext = item->tnext;
+ if (item->tnext)
+ item->tnext->tprev = item->tprev;
+ }
+}
+
+static void tlist_add_head(struct ast_hashtab_bucket **head, struct ast_hashtab_bucket *item)
+{
+ if (*head) {
+ item->tnext = *head;
+ item->tprev = NULL;
+ (*head)->tprev = item;
+ *head = item;
+ } else {
+ /* the list is empty */
+ *head = item;
+ item->tprev = NULL;
+ item->tnext = NULL;
+ }
+}
+
+/* user-controlled hashtab locking. Create a hashtab without locking, then call the
+ following locking routines yourself to lock the table between threads. */
+
+void ast_hashtab_wrlock(struct ast_hashtab *tab)
+{
+ ast_rwlock_wrlock(&tab->lock);
+}
+
+void ast_hashtab_rdlock(struct ast_hashtab *tab)
+{
+ ast_rwlock_rdlock(&tab->lock);
+}
+
+void ast_hashtab_initlock(struct ast_hashtab *tab)
+{
+ ast_rwlock_init(&tab->lock);
+}
+
+void ast_hashtab_destroylock(struct ast_hashtab *tab)
+{
+ ast_rwlock_destroy(&tab->lock);
+}
+
+void ast_hashtab_unlock(struct ast_hashtab *tab)
+{
+ ast_rwlock_unlock(&tab->lock);
+}
+
+void ast_hashtab_destroy( struct ast_hashtab *tab, void (*objdestroyfunc)(void *obj))
+{
+ /* this func will free the hash table and all its memory. It
+ doesn't touch the objects stored in it */
+ if (tab) {
+
+ if (tab->do_locking)
+ ast_rwlock_wrlock(&tab->lock);
+
+ if (tab->array) {
+ /* go thru and destroy the buckets */
+ struct ast_hashtab_bucket *t;
+ int i;
+
+ while (tab->tlist) {
+ t = tab->tlist;
+ if (t->object && objdestroyfunc)
+ (*objdestroyfunc)((void *) t->object); /* I cast this because I'm not going to MOD it, I'm going to DESTROY it */
+
+ tlist_del_item(&(tab->tlist), tab->tlist);
+ free(t);
+ }
+
+ for (i = 0; i < tab->hash_tab_size; i++)
+ tab->array[i] = NULL; /* not totally necc., but best to destroy old ptrs */
+
+ free(tab->array);
+ }
+ if (tab->do_locking) {
+ ast_rwlock_unlock(&tab->lock);
+ ast_rwlock_destroy(&tab->lock);
+ }
+ free(tab);
+ }
+}
+
+int ast_hashtab_insert_immediate(struct ast_hashtab *tab, const void *obj)
+{
+ unsigned int h;
+ int res=0;
+
+ if (!tab || !obj)
+ return res;
+
+ if (tab->do_locking)
+ ast_rwlock_wrlock(&tab->lock);
+
+ h = (*tab->hash)(obj) % tab->hash_tab_size;
+
+ res = ast_hashtab_insert_immediate_bucket(tab,obj,h);
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return res;
+}
+
+int ast_hashtab_insert_immediate_bucket(struct ast_hashtab *tab, const void *obj, unsigned int h)
+{
+ int c;
+ struct ast_hashtab_bucket *b;
+
+ if (!tab || !obj)
+ return 0;
+
+ for (c = 0, b = tab->array[h]; b; b= b->next)
+ c++;
+
+ if (c + 1 > tab->largest_bucket_size)
+ tab->largest_bucket_size = c + 1;
+
+ if (!(b = ast_calloc(1, sizeof(*b))))
+ return 0;
+
+ b->object = obj;
+ b->next = tab->array[h];
+ tab->array[h] = b;
+
+ if (b->next)
+ b->next->prev = b;
+
+ tlist_add_head(&(tab->tlist), b);
+ tab->hash_tab_elements++;
+
+ if ((*tab->resize)(tab))
+ ast_hashtab_resize(tab);
+
+ return 1;
+}
+
+int ast_hashtab_insert_safe(struct ast_hashtab *tab, const void *obj)
+{
+ /* check to see if the element is already there; insert only if
+ it is not there. */
+ /* will force a resize if the resize func returns 1 */
+ /* returns 1 on success, 0 if there's a problem, or it's already there. */
+ unsigned int bucket = 0;
+
+ if (tab->do_locking)
+ ast_rwlock_wrlock(&tab->lock);
+
+ if (!ast_hashtab_lookup_bucket(tab, obj, &bucket)) {
+ int ret2 = ast_hashtab_insert_immediate_bucket(tab, obj, bucket);
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return ret2;
+ }
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return 0;
+}
+
+void *ast_hashtab_lookup(struct ast_hashtab *tab, const void *obj)
+{
+ /* lookup this object in the hash table. return a ptr if found, or NULL if not */
+ unsigned int h;
+ void *ret;
+
+ if (!tab || !obj)
+ return 0;
+
+ if (tab->do_locking)
+ ast_rwlock_rdlock(&tab->lock);
+
+ h = (*tab->hash)(obj) % tab->hash_tab_size;
+
+ ret = ast_hashtab_lookup_internal(tab,obj,h);
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return ret;
+}
+
+
+void *ast_hashtab_lookup_with_hash(struct ast_hashtab *tab, const void *obj, unsigned int hashval)
+{
+ /* lookup this object in the hash table. return a ptr if found, or NULL if not */
+ unsigned int h;
+ void *ret;
+
+ if (!tab || !obj)
+ return 0;
+
+ if (tab->do_locking)
+ ast_rwlock_rdlock(&tab->lock);
+
+ h = hashval % tab->hash_tab_size;
+
+ ret = ast_hashtab_lookup_internal(tab,obj,h);
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return ret;
+}
+
+void *ast_hashtab_lookup_bucket(struct ast_hashtab *tab, const void *obj, unsigned int *bucket)
+{
+ /* lookup this object in the hash table. return a ptr if found, or NULL if not */
+ unsigned int h;
+ void *ret;
+
+ if (!tab || !obj)
+ return 0;
+
+ h = (*tab->hash)(obj) % tab->hash_tab_size;
+
+ ret = ast_hashtab_lookup_internal(tab,obj,h);
+
+ *bucket = h;
+
+ return ret;
+}
+
+static void *ast_hashtab_lookup_internal(struct ast_hashtab *tab, const void *obj, unsigned int h)
+{
+ struct ast_hashtab_bucket *b;
+
+ for (b = tab->array[h]; b; b = b->next) {
+ if (!(*tab->compare)(obj,b->object)) {
+ return (void*) b->object; /* I can't touch obj in this func, but the outside world is welcome to */
+ }
+ }
+
+ return NULL;
+}
+
+void ast_hashtab_get_stats( struct ast_hashtab *tab, int *biggest_bucket_size, int *resize_count, int *num_objects, int *num_buckets)
+{
+ /* returns key stats for the table */
+ if (tab->do_locking)
+ ast_rwlock_rdlock(&tab->lock);
+ *biggest_bucket_size = tab->largest_bucket_size;
+ *resize_count = tab->resize_count;
+ *num_objects = tab->hash_tab_elements;
+ *num_buckets = tab->hash_tab_size;
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+}
+
+ /* this function returns the number of elements stored in the hashtab */
+int ast_hashtab_size( struct ast_hashtab *tab)
+{
+ return tab->hash_tab_elements;
+}
+
+ /* this function returns the size of the bucket array in the hashtab */
+int ast_hashtab_capacity( struct ast_hashtab *tab)
+{
+ return tab->hash_tab_size;
+}
+
+
+
+/* the insert operation calls this, and is wrlock'd when it does. */
+/* if you want to call it, you should set the wrlock yourself */
+
+
+static void ast_hashtab_resize( struct ast_hashtab *tab)
+{
+ /* this function is called either internally, when the resize func returns 1, or
+ externally by the user to force a resize of the hash table */
+ int newsize = (*tab->newsize)(tab), i, c;
+ unsigned int h;
+ struct ast_hashtab_bucket *b,*bn;
+
+ /* Since we keep a DLL of all the buckets in tlist,
+ all we have to do is free the array, malloc a new one,
+ and then go thru the tlist array and reassign them into
+ the bucket arrayj.
+ */
+ for (i = 0; i < tab->hash_tab_size; i++) { /* don't absolutely have to do this, but
+ why leave ptrs laying around */
+ tab->array[i] = 0; /* erase old ptrs */
+ }
+ free(tab->array);
+ if (!(tab->array = ast_calloc(newsize, sizeof(*(tab->array)))))
+ return;
+
+ /* now sort the buckets into their rightful new slots */
+ tab->resize_count++;
+ tab->hash_tab_size = newsize;
+ tab->largest_bucket_size = 0;
+
+ for (b = tab->tlist; b; b = bn) {
+ b->prev = 0;
+ bn = b->tnext;
+ h = (*tab->hash)(b->object) % tab->hash_tab_size;
+ b->next = tab->array[h];
+ if (b->next)
+ b->next->prev = b;
+ tab->array[h] = b;
+ }
+ /* recalc the largest bucket size */
+ for (i = 0; i < tab->hash_tab_size; i++) {
+ for (c = 0, b = tab->array[i]; b; b = b->next)
+ c++;
+ if (c > tab->largest_bucket_size)
+ tab->largest_bucket_size = c;
+ }
+}
+
+struct ast_hashtab_iter *ast_hashtab_start_traversal(struct ast_hashtab *tab)
+{
+ /* returns an iterator */
+ struct ast_hashtab_iter *it;
+
+ if (!(it = ast_calloc(1, sizeof(*it))))
+ return NULL;
+
+ it->next = tab->tlist;
+ it->tab = tab;
+ if (tab->do_locking)
+ ast_rwlock_rdlock(&tab->lock);
+
+ return it;
+}
+
+/* use this function to get a write lock */
+struct ast_hashtab_iter *ast_hashtab_start_write_traversal(struct ast_hashtab *tab)
+{
+ /* returns an iterator */
+ struct ast_hashtab_iter *it;
+
+ if (!(it = ast_calloc(1, sizeof(*it))))
+ return NULL;
+
+ it->next = tab->tlist;
+ it->tab = tab;
+ if (tab->do_locking)
+ ast_rwlock_wrlock(&tab->lock);
+
+ return it;
+}
+
+void ast_hashtab_end_traversal(struct ast_hashtab_iter *it)
+{
+ if (it->tab->do_locking)
+ ast_rwlock_unlock(&it->tab->lock);
+ free(it);
+}
+
+void *ast_hashtab_next(struct ast_hashtab_iter *it)
+{
+ /* returns the next object in the list, advances iter one step */
+ struct ast_hashtab_bucket *retval;
+
+ if (it && it->next) { /* there's a next in the bucket list */
+ retval = it->next;
+ it->next = retval->tnext;
+ return (void *) retval->object;
+ }
+
+ return NULL;
+}
+
+static void *ast_hashtab_remove_object_internal(struct ast_hashtab *tab, struct ast_hashtab_bucket *b, int h)
+{
+ const void *obj2;
+
+ if (b->prev)
+ b->prev->next = b->next;
+ else
+ tab->array[h] = b->next;
+
+ if (b->next)
+ b->next->prev = b->prev;
+
+ tlist_del_item(&(tab->tlist), b);
+
+ obj2 = b->object;
+ b->object = b->next = (void*)2;
+ free(b); /* free up the hashbucket */
+ tab->hash_tab_elements--;
+#ifdef DEBUG
+ {
+ int c2;
+ struct ast_hashtab_bucket *b2;
+ /* do a little checking */
+ for (c2 = 0, b2 = tab->tlist; b2; b2 = b2->tnext) {
+ c2++;
+ }
+ if (c2 != tab->hash_tab_elements) {
+ printf("Hey! we didn't delete right! there are %d elements in the list, and we expected %d\n",
+ c2, tab->hash_tab_elements);
+ }
+ for (c2 = 0, b2 = tab->tlist; b2; b2 = b2->tnext) {
+ unsigned int obj3 = (unsigned long) obj2;
+ unsigned int b3 = (unsigned long) b;
+ if (b2->object == obj2)
+ printf("Hey-- you've still got a bucket pointing at ht_element %x\n", obj3);
+ if (b2->next == b)
+ printf("Hey-- you've still got a bucket with next ptr pointing to deleted bucket %x\n", b3);
+ if (b2->prev == b)
+ printf("Hey-- you've still got a bucket with prev ptr pointing to deleted bucket %x\n", b3);
+ if (b2->tprev == b)
+ printf("Hey-- you've still got a bucket with tprev ptr pointing to deleted bucket %x\n", b3);
+ if (b2->tnext == b)
+ printf("Hey-- you've still got a bucket with tnext ptr pointing to deleted bucket %x\n", b3);
+ }
+ }
+#endif
+ return (void *) obj2; /* inside this code, the obj's are untouchable, but outside, they aren't */
+}
+
+void *ast_hashtab_remove_object_via_lookup(struct ast_hashtab *tab, void *obj)
+{
+ /* looks up the object; removes the corresponding bucket */
+ const void *obj2;
+
+ if (!tab || !obj)
+ return 0;
+
+ if (tab->do_locking)
+ ast_rwlock_wrlock(&tab->lock);
+
+ obj2 = ast_hashtab_remove_object_via_lookup_nolock(tab,obj);
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return (void *)obj2;
+}
+
+void *ast_hashtab_remove_object_via_lookup_nolock(struct ast_hashtab *tab, void *obj)
+{
+ /* looks up the object; removes the corresponding bucket */
+ unsigned int h;
+ struct ast_hashtab_bucket *b;
+
+ if (!tab || !obj)
+ return 0;
+
+ h = (*tab->hash)(obj) % tab->hash_tab_size;
+ for (b = tab->array[h]; b; b = b->next) {
+
+ if (!(*tab->compare)(obj, b->object)) {
+ const void *obj2;
+
+ obj2 = ast_hashtab_remove_object_internal(tab, b, h);
+
+ return (void *) obj2; /* inside this code, the obj's are untouchable, but outside, they aren't */
+ }
+ }
+
+ return 0;
+}
+
+void *ast_hashtab_remove_this_object(struct ast_hashtab *tab, void *obj)
+{
+ /* looks up the object by hash and then comparing pts in bucket list instead of
+ calling the compare routine; removes the bucket -- a slightly cheaper operation */
+ /* looks up the object; removes the corresponding bucket */
+ const void *obj2;
+
+ if (!tab || !obj)
+ return 0;
+
+ if (tab->do_locking)
+ ast_rwlock_wrlock(&tab->lock);
+
+ obj2 = ast_hashtab_remove_this_object_nolock(tab,obj);
+
+ if (tab->do_locking)
+ ast_rwlock_unlock(&tab->lock);
+
+ return (void *)obj2;
+}
+
+void *ast_hashtab_remove_this_object_nolock(struct ast_hashtab *tab, void *obj)
+{
+ /* looks up the object by hash and then comparing pts in bucket list instead of
+ calling the compare routine; removes the bucket -- a slightly cheaper operation */
+ /* looks up the object; removes the corresponding bucket */
+ unsigned int h;
+ struct ast_hashtab_bucket *b;
+
+ if (!tab || !obj)
+ return 0;
+
+ h = (*tab->hash)(obj) % tab->hash_tab_size;
+ for (b = tab->array[h]; b; b = b->next) {
+
+ if (obj == b->object) {
+ const void *obj2;
+ obj2 = ast_hashtab_remove_object_internal(tab, b, h);
+
+ return (void *) obj2; /* inside this code, the obj's are untouchable, but outside, they aren't */
+ }
+ }
+
+ return 0;
+}