6:43 p.m.
Author: mladen.turk(a)jboss.com
Date: 2007-09-08 12:43:04 -0400 (Sat, 08 Sep 2007)
New Revision: 989
Added:
trunk/sight/native/share/cache.c
Log:
Add cache.c for list based hash
Added: trunk/sight/native/share/cache.c
===================================================================
--- trunk/sight/native/share/cache.c (rev 0)
+++ trunk/sight/native/share/cache.c 2007-09-08 16:43:04 UTC (rev 989)
@@ -0,0 +1,147 @@
+/*
+ * SIGHT - System information gathering hybrid tool
+ *
+ * Copyright(c) 2007 Red Hat Middleware, LLC,
+ * and individual contributors as indicated by the @authors tag.
+ * See the copyright.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * 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 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 in the file COPYING.LIB;
+ * if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ *
+ * @author Mladen Turk
+ *
+ */
+
+#include "sight.h"
+#include "sight_local.h"
+#include "sight_types.h"
+
+static unsigned int times33hash(const char *key)
+{
+ const char *p;
+ unsigned int hash = 0;
+ for (p = key; *p; p++) {
+ hash = hash * 33 + *p;
+ }
+ return hash & CACHE_HASH_MASK;
+}
+
+cache_table_t *cache_new(size_t init)
+{
+ cache_table_t *t = (cache_table_t *)malloc(sizeof(cache_table_t));
+ if (!t)
+ return NULL;
+ t->siz = 0;
+ t->len = init;
+ if (!(t->list = (cache_entry_t **)malloc(init * sizeof(cache_entry_t *)))) {
+ int saved = errno;
+ free(t);
+ t = NULL;
+ errno = saved;
+ }
+ return t;
+}
+
+cache_entry_t *cache_add(cache_table_t *t, const char *key)
+{
+ cache_entry_t *e;
+ unsigned int hash;
+
+ if (!key || !*key) {
+ errno = EINVAL;
+ return NULL; /* Skip empty and null strings */
+ }
+ hash = times33hash(key);
+
+ if (t->hash[hash]) {
+ /*
+ * This spot in the table is already in use. See if the current string
+ * has already been inserted, and if so, increment its count.
+ */
+ for (e = t->hash[hash]; e; e = e->next) {
+ if (!strcmp(key, e->key))
+ return e;
+ }
+ }
+ if (!(e = (cache_entry_t *)malloc(sizeof(cache_entry_t ))))
+ return NULL;
+ e->data = NULL;
+ /* Insert new bucket into the list */
+ if (t->siz < t->len) {
+ t->list[t->siz++] = e;
+ }
+ else {
+ cache_entry_t **nl;
+ size_t len = t->len << 2;
+ if (!(nl = (cache_entry_t **)malloc(len * sizeof(cache_entry_t *))))
+ return NULL;
+ memcpy(nl, t->list, t->siz * sizeof(cache_entry_t *));
+ free(t->list);
+ t->len = len;
+ t->list = nl;
+ t->list[t->siz++] = e;
+ }
+ if (!(e->key = strdup(key)))
+ return NULL;
+ e->next = t->hash[hash];
+ t->hash[hash] = e;
+ return e;
+}
+
+cache_entry_t *cache_find(cache_table_t *t, const char *key)
+{
+ cache_entry_t *e;
+ unsigned int hash;
+
+ if (!key || !*key) {
+ return NULL; /* Skip empty and null strings */
+ }
+ hash = times33hash(key);
+
+ if (t->hash[hash]) {
+ /*
+ * This spot in the table is already in use. See if the current string
+ * has already been inserted, and if so, return existing entry.
+ */
+ for (e = t->hash[hash]; e; e = e->next) {
+ if (!strcmp(key, e->key))
+ return e;
+ }
+ }
+ return NULL;
+}
+
+void cache_free(cache_table_t *t, void (*destroy)(const char *, void *))
+{
+ size_t i;
+
+ if (!t)
+ return;
+ for (i = 0; i < t->siz; i++) {
+ if (t->list[i]) {
+ if (t->list[i]->data) {
+ if (destroy)
+ (*destroy)(t->list[i]->key, t->list[i]->data);
+ else
+ free(t->list[i]->data);
+ }
+ if (t->list[i]->key)
+ free(t->list[i]->key);
+ }
+ }
+ free(t->list);
+ free(t);
+}
Property changes on: trunk/sight/native/share/cache.c
___________________________________________________________________
Name: svn:eol-style
+ native