From 024e755d9f3c33e742ce158542b1ded057a88f4f Mon Sep 17 00:00:00 2001 From: Nikias Bassen Date: Fri, 27 May 2011 14:55:31 +0200 Subject: Make libplist glib free --- src/hashtable.c | 107 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) create mode 100644 src/hashtable.c (limited to 'src/hashtable.c') diff --git a/src/hashtable.c b/src/hashtable.c new file mode 100644 index 0000000..9716c25 --- /dev/null +++ b/src/hashtable.c @@ -0,0 +1,107 @@ +/* + * hashtable.c + * really simple hash table implementation + * + * Copyright (c) 2011 Nikias Bassen, All Rights Reserved. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ +#include "hashtable.h" + +hashtable_t* hash_table_new(hash_func_t hash_func, compare_func_t compare_func) +{ + hashtable_t* ht = (hashtable_t*)malloc(sizeof(hashtable_t)); + int i; + for (i = 0; i < 256; i++) { + ht->entries[i] = NULL; + } + ht->count = 0; + ht->hash_func = hash_func; + ht->compare_func = compare_func; + return ht; +} + +void hash_table_destroy(hashtable_t *ht) +{ + if (!ht) return; + + int i = 0; + for (i = 0; i < 256; i++) { + if (ht->entries[i]) { + hashentry_t* e = ht->entries[i]; + while (e) { + free(e->value); + hashentry_t* old = e; + e = e->next; + free(old); + } + } + } + free(ht); +} + +void hash_table_insert(hashtable_t* ht, void *key, void *value) +{ + if (!ht || !key) return; + int i; + + unsigned int hash = ht->hash_func(key); + + int idx0 = hash & 0xFF; + + // get the idx0 list + hashentry_t* e = ht->entries[idx0]; + while (e) { + if (ht->compare_func(e->key, key)) { + // element already present. replace value. + e->value = value; + return; + } + e = e->next; + } + + // if we get here, the element is not yet in the list. + + // make a new entry. + hashentry_t* entry = (hashentry_t*)malloc(sizeof(hashentry_t)); + entry->key = key; + entry->value = value; + if (!ht->entries[idx0]) { + // first entry + entry->next = NULL; + } else { + // add to list + entry->next = ht->entries[idx0]; + } + ht->entries[idx0] = entry; + ht->count++; +} + +void* hash_table_lookup(hashtable_t* ht, void *key) +{ + if (!ht || !key) return NULL; + unsigned int hash = ht->hash_func(key); + + int idx0 = hash & 0xFF; + + hashentry_t* e = ht->entries[idx0]; + while (e) { + if (ht->compare_func(e->key, key)) { + return e->value; + } + e = e->next; + } + return NULL; +} -- cgit v1.1-32-gdbae