You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

158 lines
2.5 KiB

#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);
}
}