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-rw-r--r--Utilities/cmcurl/hash.c315
1 files changed, 315 insertions, 0 deletions
diff --git a/Utilities/cmcurl/hash.c b/Utilities/cmcurl/hash.c
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+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * $Id$
+ ***************************************************************************/
+
+#include "setup.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+#include "hash.h"
+#include "llist.h"
+#include "memory.h"
+
+/* this must be the last include file */
+#include "memdebug.h"
+
+static unsigned long
+hash_str(const char *key, size_t key_length)
+{
+ char *end = (char *) key + key_length;
+ unsigned long h = 5381;
+
+ while (key < end) {
+ h += h << 5;
+ h ^= (unsigned long) *key++;
+ }
+
+ return h;
+}
+
+static void
+hash_element_dtor(void *user, void *element)
+{
+ struct curl_hash *h = (struct curl_hash *) user;
+ struct curl_hash_element *e = (struct curl_hash_element *) element;
+
+ if (e->key)
+ free(e->key);
+
+ h->dtor(e->ptr);
+
+ free(e);
+}
+
+/* return 1 on error, 0 is fine */
+int
+Curl_hash_init(struct curl_hash *h, int slots, curl_hash_dtor dtor)
+{
+ int i;
+
+ h->dtor = dtor;
+ h->size = 0;
+ h->slots = slots;
+
+ h->table = (struct curl_llist **) malloc(slots * sizeof(struct curl_llist *));
+ if(h->table) {
+ for (i = 0; i < slots; ++i) {
+ h->table[i] = Curl_llist_alloc((curl_llist_dtor) hash_element_dtor);
+ if(!h->table[i]) {
+ while(i--)
+ Curl_llist_destroy(h->table[i], NULL);
+ free(h->table);
+ return 1; /* failure */
+ }
+ }
+ return 0; /* fine */
+ }
+ else
+ return 1; /* failure */
+}
+
+struct curl_hash *
+Curl_hash_alloc(int slots, curl_hash_dtor dtor)
+{
+ struct curl_hash *h;
+
+ h = (struct curl_hash *) malloc(sizeof(struct curl_hash));
+ if (h) {
+ if(Curl_hash_init(h, slots, dtor)) {
+ /* failure */
+ free(h);
+ h = NULL;
+ }
+ }
+
+ return h;
+}
+
+static int
+hash_key_compare(char *key1, size_t key1_len, char *key2, size_t key2_len)
+{
+ if (key1_len == key2_len &&
+ *key1 == *key2 &&
+ memcmp(key1, key2, key1_len) == 0) {
+ return 1;
+ }
+
+ return 0;
+}
+
+static struct curl_hash_element *
+mk_hash_element(char *key, size_t key_len, const void *p)
+{
+ struct curl_hash_element *he =
+ (struct curl_hash_element *) malloc(sizeof(struct curl_hash_element));
+
+ if(he) {
+ char *dup = malloc(key_len);
+ if(dup) {
+ /* copy the key */
+ memcpy(dup, key, key_len);
+
+ he->key = dup;
+ he->key_len = key_len;
+ he->ptr = (void *) p;
+ }
+ else {
+ /* failed to duplicate the key, free memory and fail */
+ free(he);
+ he = NULL;
+ }
+ }
+ return he;
+}
+
+#define find_slot(__h, __k, __k_len) (hash_str(__k, __k_len) % (__h)->slots)
+
+#define FETCH_LIST(x,y,z) x->table[find_slot(x, y, z)]
+
+/* Return the data in the hash. If there already was a match in the hash,
+ that data is returned. */
+void *
+Curl_hash_add(struct curl_hash *h, char *key, size_t key_len, void *p)
+{
+ struct curl_hash_element *he;
+ struct curl_llist_element *le;
+ struct curl_llist *l = FETCH_LIST(h, key, key_len);
+
+ for (le = l->head; le; le = le->next) {
+ he = (struct curl_hash_element *) le->ptr;
+ if (hash_key_compare(he->key, he->key_len, key, key_len)) {
+ h->dtor(p); /* remove the NEW entry */
+ return he->ptr; /* return the EXISTING entry */
+ }
+ }
+
+ he = mk_hash_element(key, key_len, p);
+ if (he) {
+ if(Curl_llist_insert_next(l, l->tail, he)) {
+ ++h->size;
+ return p; /* return the new entry */
+ }
+ /*
+ * Couldn't insert it, destroy the 'he' element and the key again. We
+ * don't call hash_element_dtor() since that would also call the
+ * "destructor" for the actual data 'p'. When we fail, we shall not touch
+ * that data.
+ */
+ free(he->key);
+ free(he);
+ }
+
+ return NULL; /* failure */
+}
+
+/* remove the identified hash entry, returns non-zero on failure */
+int Curl_hash_delete(struct curl_hash *h, char *key, size_t key_len)
+{
+ struct curl_llist_element *le;
+ struct curl_hash_element *he;
+ struct curl_llist *l = FETCH_LIST(h, key, key_len);
+
+ for (le = l->head; le; le = le->next) {
+ he = le->ptr;
+ if (hash_key_compare(he->key, he->key_len, key, key_len)) {
+ Curl_llist_remove(l, le, (void *) h);
+ return 0;
+ }
+ }
+ return 1;
+}
+
+void *
+Curl_hash_pick(struct curl_hash *h, char *key, size_t key_len)
+{
+ struct curl_llist_element *le;
+ struct curl_hash_element *he;
+ struct curl_llist *l = FETCH_LIST(h, key, key_len);
+
+ for (le = l->head; le; le = le->next) {
+ he = le->ptr;
+ if (hash_key_compare(he->key, he->key_len, key, key_len)) {
+ return he->ptr;
+ }
+ }
+
+ return NULL;
+}
+
+#if defined(CURLDEBUG) && defined(AGGRESIVE_TEST)
+void
+Curl_hash_apply(curl_hash *h, void *user,
+ void (*cb)(void *user, void *ptr))
+{
+ struct curl_llist_element *le;
+ int i;
+
+ for (i = 0; i < h->slots; ++i) {
+ for (le = (h->table[i])->head;
+ le;
+ le = le->next) {
+ curl_hash_element *el = le->ptr;
+ cb(user, el->ptr);
+ }
+ }
+}
+#endif
+
+void
+Curl_hash_clean(struct curl_hash *h)
+{
+ int i;
+
+ for (i = 0; i < h->slots; ++i) {
+ Curl_llist_destroy(h->table[i], (void *) h);
+ }
+
+ free(h->table);
+}
+
+void
+Curl_hash_clean_with_criterium(struct curl_hash *h, void *user,
+ int (*comp)(void *, void *))
+{
+ struct curl_llist_element *le;
+ struct curl_llist_element *lnext;
+ struct curl_llist *list;
+ int i;
+
+ for (i = 0; i < h->slots; ++i) {
+ list = h->table[i];
+ le = list->head; /* get first list entry */
+ while(le) {
+ struct curl_hash_element *he = le->ptr;
+ lnext = le->next;
+ /* ask the callback function if we shall remove this entry or not */
+ if (comp(user, he->ptr)) {
+ Curl_llist_remove(list, le, (void *) h);
+ --h->size; /* one less entry in the hash now */
+ }
+ le = lnext;
+ }
+ }
+}
+
+void
+Curl_hash_destroy(struct curl_hash *h)
+{
+ if (!h)
+ return;
+
+ Curl_hash_clean(h);
+ free(h);
+}
+
+#if 0 /* useful function for debugging hashes and their contents */
+void Curl_hash_print(struct curl_hash *h,
+ void (*func)(void *))
+{
+ int i;
+ struct curl_llist_element *le;
+ struct curl_llist *list;
+ struct curl_hash_element *he;
+ if (!h)
+ return;
+
+ fprintf(stderr, "=Hash dump=\n");
+
+ for (i = 0; i < h->slots; i++) {
+ list = h->table[i];
+ le = list->head; /* get first list entry */
+ if(le) {
+ fprintf(stderr, "index %d:", i);
+ while(le) {
+ he = le->ptr;
+ if(func)
+ func(he->ptr);
+ else
+ fprintf(stderr, " [%p]", he->ptr);
+ le = le->next;
+ }
+ fprintf(stderr, "\n");
+ }
+ }
+}
+#endif