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/*
Copyright 2002 Matthew Allum
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, 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.
*/
#include "hash.h"
// static struct nlist *hashtab[HASHSIZE];
struct hash*
hash_new(int size)
{
struct hash *h = (struct hash *)(malloc(sizeof(struct hash)));
h->size = size;
h->hashtab = (struct nlist **)(malloc(sizeof(struct nlist)*size));
memset((void *)h->hashtab, 0, sizeof(struct nlist)*size);
return h;
}
unsigned int hashfunc(struct hash *h, char *s)
{
unsigned int hashval;
for(hashval = 0; *s != '\0'; s++)
hashval = *s + 21 * hashval;
return hashval % h->size;
}
struct nlist *hash_lookup(struct hash *h, char *s)
{
struct nlist *np;
for (np = h->hashtab[hashfunc(h, s)]; np != NULL; np = np->next)
if (strcmp(s, np->key) == 0)
return np;
return NULL;
}
struct nlist *hash_add(struct hash *h, char *key, char *val)
{
struct nlist *np;
unsigned int hashval;
if ((np = hash_lookup(h, key)) == NULL)
{
np = (struct nlist * ) malloc(sizeof(*np));
if ( np == NULL || (np->key = strdup(key)) == NULL)
return NULL;
hashval = hashfunc(h, key);
np->next = h->hashtab[hashval];
h->hashtab[hashval] = np;
} else {
free((void *) np->value);
}
if ((np->value = strdup(val)) == NULL)
return NULL;
return np;
}
void hash_empty(struct hash *h)
{
memset(h->hashtab, 0, sizeof(h->hashtab));
}
void
hash_destroy(struct hash *h)
{
free(h->hashtab);
free(h);
}
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