[jbossnative-commits] JBoss Native SVN: r989 - trunk/sight/native/share.

[jbossnative-commits at lists.jboss.org]

Author: mladen.turk at 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