Hash table question, code posted (~40ines)

From: exonic (exonic_at_triton.net)
Date: 03/31/04 

Date: Wed, 31 Mar 2004 12:23:33 -0500

I am having some trouble with a hash table routine, I have
a few problems with figuring out why I can't access the table in
the hash_t structure. And weather or not I have a decent hashing
function written. I am simply using modulus. This project is a
test to help me understand the 5W's of hashing..

Here are my structs
--------------------
#ifndef HAVE_HASH_H
#define HAVE_HASH_H

#include <stdlib.h>
#include <stdio.h>

typedef struct {
        unsigned int value;
} htable_t;

typedef struct {
        size_t size;
        htable_t *table;
} hash_t;

/* prototypes */
hash_t *hash_init(hash_t *h, size_t size);
int hash_index(hash_t *h, unsigned int value);
int hash_add(hash_t *h, unsigned int value);
int hash_find(hash_t *h, unsigned int value);
int hash_print(hash_t *h);
int hash_free(hash_t *h);

#endif

Here is my code
-------------
hash_t *hash_init(hash_t *h, size_t size) {
        htable_t *table;
        h = malloc(sizeof(hash_t));
        if (!h) return NULL;
        h->size = size;
        table = malloc(sizeof(htable_t) * size);
        if (!table) return NULL;
        h->table = table;
        printf("hash_init(): struct pointer %p, size %d %d\n", h, size, h->size);
        return h;
}
int hash_index(hash_t *h, unsigned int value) {
        int i, size;
        size = h->size;
        i = (int) value % size;
        return i;
}
int hash_add(hash_t *h, unsigned int value) {
        int size, i;
        htable_t *table;
        size = h->size;
        table = h->table;
        i = hash_index(h, value);
        printf("hash_add(): struct pointer %p, index %d\n", h, i);

/*
        Here is where I can't figure out how to access the table, I thought this
        was valid but doesn't seem to work.
        table[i]++;
*/

        return 0;
}
int hash_find(hash_t *h, unsigned int value) {
        return 0;
}
int hash_print(hash_t *h) {
        int i,size;
        htable_t *table;
        table = h->table;
        size = h->size;
        printf("hash_print(): struct pointer %p, size %d\n", h, size);
        for(i=0; i<size; i++) {
                /* I don't know if I am acessing the table correctly here either */
                printf("table[%d] = %d\n", i, (int) table[i]);
        }
        return 0;
}
int hash_free(hash_t *h) {
        free(h->table);
        free(h);
        return 0;
}

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