root/trunk/freewrt/tools/nfotizer/hash.c

/* nfotizer - split information given in info.nfo files into several places.
 * Copyright (C) 2007  Phil Sutter <n0-1@freewrt.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
#include "nfotizer.h"
#include <stdlib.h>             /* malloc */
#include <string.h>             /* strcmp */

/* Create a new hash table.
 * This initially holds size elements,
 * but is dynamically growing. */
struct htab *
htab_create(int size)
{
        struct htab *table = malloc(sizeof(struct htab));
        table->size = size;
        table->data = calloc(size, sizeof(struct entry));
        table->items = 0;
        return table;
}

/* destroy a hash table, freeing it's space */
void
htab_destroy(struct htab *tab)
{
        int i = 0;
        for (; i < tab->size; i++) {
                zap(tab->data[i].key);
                zap(tab->data[i].val);
        }
        zap(tab->data);
        zap(tab);
}

/* return the index of key in the hash table tab or -1 if not found */
int
htab_indexof(char *key, struct htab tab)
{
        int i = 0;
        for (; i < tab.items; i++) {
                if (!strcmp(key, tab.data[i].key)) {
                        DBG("struct htab_indexof(): found \"%s\" at %i", key, i);
                        return i;
                }
        }
        return -1;
}

/* return the value of key in tab */
char *
htab_get(char *key, struct htab tab)
{
        int i;
        if ((i = htab_indexof(key, tab)) >= 0)
                return strdup(tab.data[i].val);
        else
                return NULL;
}

/* insert key with value val into tab */
int
htab_put(char *key, char *val, struct htab *tab)
{
        if (htab_indexof(key, *tab) >= 0)
                return -1;
        if (tab->items == tab->size) {
                tab->size = tab->size << 2;
                DBG("resizing hash to %i items", tab->size);
                tab->data = realloc(tab->data, tab->size);
        }
        tab->data[tab->items].key = strdup(key);
        tab->data[tab->items].val = strdup(val);
        DBG("inserted item: %s: %s", tab->data[tab->items].key,
              tab->data[tab->items].val);
        tab->items++;
        return 0;
}

/* print the whole hash table tab */
void
htab_print(struct htab tab)
{
        int i=0;
        for (; i < tab.items; i++)
                PINFO("%s: %s", tab.data[i].key, tab.data[i].val);
}