182 lines
3.5 KiB
C
182 lines
3.5 KiB
C
/***************************************************************************
|
|
* hash.c
|
|
*
|
|
* Copyright 2006 Philippe Rouquier
|
|
* Bonfire-app@wanadoo.fr
|
|
***************************************************************************/
|
|
|
|
/*
|
|
* 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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "hash.h"
|
|
|
|
static unsigned int
|
|
iso_hash_path(const char *path)
|
|
{
|
|
unsigned int hash_num=0;
|
|
const char *c;
|
|
|
|
c=path;
|
|
while(*c)
|
|
hash_num = (hash_num << 15) + (hash_num << 3) + (hash_num >> 3) + *c++;
|
|
|
|
return hash_num % HASH_NODES;
|
|
}
|
|
|
|
int
|
|
iso_hash_lookup(struct iso_hash_node **table, const char *path)
|
|
{
|
|
struct iso_hash_node *node;
|
|
unsigned int hash_num;
|
|
|
|
hash_num = iso_hash_path(path);
|
|
|
|
node=table[hash_num];
|
|
|
|
if (!node)
|
|
return 0;
|
|
|
|
if (!strcmp(path, node->path))
|
|
return 1;
|
|
|
|
while (node->next) {
|
|
node=node->next;
|
|
|
|
if (!strcmp(path, node->path))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct iso_hash_node*
|
|
iso_hash_node_new (const char *path)
|
|
{
|
|
struct iso_hash_node *node;
|
|
|
|
/*create an element to be inserted in the hash table */
|
|
node=malloc(sizeof(struct iso_hash_node));
|
|
node->path=strdup(path);
|
|
node->next=NULL;
|
|
|
|
return node;
|
|
}
|
|
|
|
int
|
|
iso_hash_insert(struct iso_hash_node **table, const char *path)
|
|
{
|
|
struct iso_hash_node *node;
|
|
unsigned int hash_num;
|
|
|
|
/* find the hash number */
|
|
hash_num = iso_hash_path(path);
|
|
|
|
/* insert it */
|
|
node = table[hash_num];
|
|
|
|
/* unfortunately, we can't safely consider that a path
|
|
* won't be twice in the hash table so make sure it
|
|
* doesn't already exists */
|
|
if (!node) {
|
|
table[hash_num]=iso_hash_node_new(path);
|
|
return 1;
|
|
}
|
|
|
|
/* if it's already in, we don't do anything */
|
|
if (!strcmp(path, node->path))
|
|
return 0;
|
|
|
|
while (node->next) {
|
|
node = node->next;
|
|
|
|
/* if it's already in, we don't do anything */
|
|
if (!strcmp (path, node->path))
|
|
return 0;
|
|
}
|
|
|
|
node->next = iso_hash_node_new(path);
|
|
return 1;
|
|
}
|
|
|
|
static void
|
|
iso_hash_node_free(struct iso_hash_node *node)
|
|
{
|
|
free(node->path);
|
|
free(node);
|
|
}
|
|
|
|
int
|
|
iso_hash_remove(struct iso_hash_node **table, const char *path)
|
|
{
|
|
unsigned int hash_num;
|
|
struct iso_hash_node *node;
|
|
|
|
hash_num = iso_hash_path(path);
|
|
|
|
node=table[hash_num];
|
|
if (!node)
|
|
return 0;
|
|
|
|
if (!strcmp(path, node->path)) {
|
|
table[hash_num]=node->next;
|
|
iso_hash_node_free(node);
|
|
return 1;
|
|
}
|
|
|
|
while (node->next) {
|
|
struct iso_hash_node *prev;
|
|
|
|
prev = node;
|
|
node = node->next;
|
|
|
|
if (!strcmp (path, node->path)) {
|
|
prev->next=node->next;
|
|
iso_hash_node_free(node);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
iso_hash_empty(struct iso_hash_node **table)
|
|
{
|
|
int i;
|
|
|
|
for (i=0; i < HASH_NODES; i++) {
|
|
struct iso_hash_node *node;
|
|
|
|
node=table[i];
|
|
if (!node)
|
|
continue;
|
|
|
|
table[i]=NULL;
|
|
|
|
do {
|
|
struct iso_hash_node *next;
|
|
|
|
next=node->next;
|
|
iso_hash_node_free(node);
|
|
node=next;
|
|
} while (node);
|
|
}
|
|
}
|
|
|