/*************************************************************************** * _ _ ____ _ * 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