/*
* Copyright (C) 1996-2009 Michael R. Elkins <me@mutt.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.
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "mutt.h"
#define SOMEPRIME 149711
static unsigned int gen_string_hash (union hash_key key, unsigned int n)
{
unsigned int h = 0;
unsigned char *s = (unsigned char *)key.strkey;
while (*s)
h += (h << 7) + *s++;
h = (h * SOMEPRIME) % n;
return h;
}
static int cmp_string_key (union hash_key a, union hash_key b)
{
return mutt_strcmp (a.strkey, b.strkey);
}
static unsigned int gen_case_string_hash (union hash_key key, unsigned int n)
{
unsigned int h = 0;
unsigned char *s = (unsigned char *)key.strkey;
while (*s)
h += (h << 7) + tolower (*s++);
h = (h * SOMEPRIME) % n;
return h;
}
static int cmp_case_string_key (union hash_key a, union hash_key b)
{
return mutt_strcasecmp (a.strkey, b.strkey);
}
static unsigned int gen_int_hash (union hash_key key, unsigned int n)
{
return key.intkey % n;
}
static int cmp_int_key (union hash_key a, union hash_key b)
{
if (a.intkey == b.intkey)
return 0;
if (a.intkey < b.intkey)
return -1;
return 1;
}
static HASH *new_hash (int nelem)
{
HASH *table = safe_calloc (1, sizeof (HASH));
if (nelem == 0)
nelem = 2;
table->nelem = nelem;
table->table = safe_calloc (nelem, sizeof (struct hash_elem *));
return table;
}
HASH *hash_create (int nelem, int flags)
{
HASH *table = new_hash (nelem);
if (flags & MUTT_HASH_STRCASECMP)
{
table->gen_hash = gen_case_string_hash;
table->cmp_key = cmp_case_string_key;
}
else
{
table->gen_hash = gen_string_hash;
table->cmp_key = cmp_string_key;
}
if (flags & MUTT_HASH_STRDUP_KEYS)
table->strdup_keys = 1;
if (flags & MUTT_HASH_ALLOW_DUPS)
table->allow_dups = 1;
return table;
}
HASH *int_hash_create (int nelem, int flags)
{
HASH *table = new_hash (nelem);
table->gen_hash = gen_int_hash;
table->cmp_key = cmp_int_key;
if (flags & MUTT_HASH_ALLOW_DUPS)
table->allow_dups = 1;
return table;
}
/* table hash table to update
* key key to hash on
* data data to associate with `key'
* allow_dup if nonzero, duplicate keys are allowed in the table
*/
static int union_hash_insert (HASH * table, union hash_key key, void *data)
{
struct hash_elem *ptr;
unsigned int h;
ptr = (struct hash_elem *) safe_malloc (sizeof (struct hash_elem));
h = table->gen_hash (key, table->nelem);
ptr->key = key;
ptr->data = data;
if (table->allow_dups)
{
ptr->next = table->table[h];
table->table[h] = ptr;
}
else
{
struct hash_elem *tmp, *last;
int r;
for (tmp = table->table[h], last = NULL; tmp; last = tmp, tmp = tmp->next)
{
r = table->cmp_key (tmp->key, key);
if (r == 0)
{
FREE (&ptr);
return (-1);
}
if (r > 0)
break;
}
if (last)
last->next = ptr;
else
table->table[h] = ptr;
ptr->next = tmp;
}
return h;
}
int hash_insert (HASH * table, const char *strkey, void *data)
{
union hash_key key;
key.strkey = table->strdup_keys ? safe_strdup (strkey) : strkey;
return union_hash_insert (table, key, data);
}
int int_hash_insert (HASH * table, unsigned int intkey, void *data)
{
union hash_key key;
key.intkey = intkey;
return union_hash_insert (table, key, data);
}
static struct hash_elem *union_hash_find_elem (const HASH *table, union hash_key key)
{
int hash;
struct hash_elem *ptr;
if (!table)
return NULL;
hash = table->gen_hash (key, table->nelem);
ptr = table->table[hash];
for (; ptr; ptr = ptr->next)
{
if (table->cmp_key (key, ptr->key) == 0)
return (ptr);
}
return NULL;
}
static void *union_hash_find (const HASH *table, union hash_key key)
{
struct hash_elem *ptr = union_hash_find_elem (table, key);
if (ptr)
return ptr->data;
else
return NULL;
}
void *hash_find (const HASH *table, const char *strkey)
{
union hash_key key;
key.strkey = strkey;
return union_hash_find (table, key);
}
struct hash_elem *hash_find_elem (const HASH *table, const char *strkey)
{
union hash_key key;
key.strkey = strkey;
return union_hash_find_elem (table, key);
}
void *int_hash_find (const HASH *table, unsigned int intkey)
{
union hash_key key;
key.intkey = intkey;
return union_hash_find (table, key);
}
struct hash_elem *hash_find_bucket (const HASH *table, const char *strkey)
{
union hash_key key;
int hash;
if (!table)
return NULL;
key.strkey = strkey;
hash = table->gen_hash (key, table->nelem);
return table->table[hash];
}
static void union_hash_delete (HASH *table, union hash_key key, const void *data,
void (*destroy) (void *))
{
int hash;
struct hash_elem *ptr, **last;
if (!table)
return;
hash = table->gen_hash (key, table->nelem);
ptr = table->table[hash];
last = &table->table[hash];
while (ptr)
{
if ((data == ptr->data || !data)
&& table->cmp_key (ptr->key, key) == 0)
{
*last = ptr->next;
if (destroy)
destroy (ptr->data);
if (table->strdup_keys)
FREE (&ptr->key.strkey);
FREE (&ptr);
ptr = *last;
}
else
{
last = &ptr->next;
ptr = ptr->next;
}
}
}
void hash_delete (HASH *table, const char *strkey, const void *data,
void (*destroy) (void *))
{
union hash_key key;
key.strkey = strkey;
union_hash_delete (table, key, data, destroy);
}
void int_hash_delete (HASH *table, unsigned int intkey, const void *data,
void (*destroy) (void *))
{
union hash_key key;
key.intkey = intkey;
union_hash_delete (table, key, data, destroy);
}
/* ptr pointer to the hash table to be freed
* destroy() function to call to free the ->data member (optional)
*/
void hash_destroy (HASH **ptr, void (*destroy) (void *))
{
int i;
HASH *pptr;
struct hash_elem *elem, *tmp;
if (!ptr || !*ptr)
return;
pptr = *ptr;
for (i = 0 ; i < pptr->nelem; i++)
{
for (elem = pptr->table[i]; elem; )
{
tmp = elem;
elem = elem->next;
if (destroy)
destroy (tmp->data);
if (pptr->strdup_keys)
FREE (&tmp->key.strkey);
FREE (&tmp);
}
}
FREE (&pptr->table);
FREE (ptr); /* __FREE_CHECKED__ */
}
struct hash_elem *hash_walk(const HASH *table, struct hash_walk_state *state)
{
if (state->last && state->last->next)
{
state->last = state->last->next;
return state->last;
}
if (state->last)
state->index++;
while (state->index < table->nelem)
{
if (table->table[state->index])
{
state->last = table->table[state->index];
return state->last;
}
state->index++;
}
state->index = 0;
state->last = NULL;
return NULL;
}