/**************************************************************************
*
* Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/**
* Key lookup/associative container.
*
* Like Jose's util_hash_table, based on CSO cache code for now.
*
* Author: Brian Paul
*/
#include "pipe/p_compiler.h"
#include "util/u_debug.h"
#include "cso_cache/cso_hash.h"
#include "util/u_memory.h"
#include "util/u_keymap.h"
struct keymap
{
struct cso_hash *cso;
unsigned key_size;
unsigned max_entries; /* XXX not obeyed net */
unsigned num_entries;
keymap_delete_func delete_func;
};
struct keymap_item
{
void *key, *value;
};
/**
* This the default key-delete function used when the client doesn't
* provide one.
*/
static void
default_delete_func(const struct keymap *map,
const void *key, void *data, void *user)
{
FREE((void*) data);
}
static INLINE struct keymap_item *
hash_table_item(struct cso_hash_iter iter)
{
return (struct keymap_item *) cso_hash_iter_data(iter);
}
/**
* Return 4-byte hash key for a block of bytes.
*/
static unsigned
hash(const void *key, unsigned keySize)
{
unsigned i, hash;
keySize /= 4; /* convert from bytes to uints */
hash = 0;
for (i = 0; i < keySize; i++) {
hash ^= (i + 1) * ((const unsigned *) key)[i];
}
/*hash = hash ^ (hash >> 11) ^ (hash >> 22);*/
return hash;
}
/**
* Create a new map.
* \param keySize size of the keys in bytes
* \param maxEntries max number of entries to allow (~0 = infinity)
* \param deleteFunc optional callback to call when entries
* are deleted/replaced
*/
struct keymap *
util_new_keymap(unsigned keySize, unsigned maxEntries,
keymap_delete_func deleteFunc)
{
struct keymap *map = MALLOC_STRUCT(keymap);
if (!map)
return NULL;
map->cso = cso_hash_create();
if (!map->cso) {
FREE(map);
return NULL;
}
map->max_entries = maxEntries;
map->num_entries = 0;
map->key_size = keySize;
map->delete_func = deleteFunc ? deleteFunc : default_delete_func;
return map;
}
/**
* Delete/free a keymap and all entries. The deleteFunc that was given at
* create time will be called for each entry.
* \param user user-provided pointer passed through to the delete callback
*/
void
util_delete_keymap(struct keymap *map, void *user)
{
util_keymap_remove_all(map, user);
cso_hash_delete(map->cso);
FREE(map);
}
static INLINE struct cso_hash_iter
hash_table_find_iter(const struct keymap *map, const void *key,
unsigned key_hash)
{
struct cso_hash_iter iter;
struct keymap_item *item;
iter = cso_hash_find(map->cso, key_hash);
while (!cso_hash_iter_is_null(iter)) {
item = (struct keymap_item *) cso_hash_iter_data(iter);
if (!memcmp(item
->key
, key
, map
->key_size
)) break;
iter = cso_hash_iter_next(iter);
}
return iter;
}
static INLINE struct keymap_item *
hash_table_find_item(const struct keymap *map, const void *key,
unsigned key_hash)
{
struct cso_hash_iter iter = hash_table_find_iter(map, key, key_hash);
if (cso_hash_iter_is_null(iter)) {
return NULL;
}
else {
return hash_table_item(iter);
}
}
/**
* Insert a new key + data pointer into the table.
* Note: we create a copy of the key, but not the data!
* If the key is already present in the table, replace the existing
* entry (calling the delete callback on the previous entry).
* If the maximum capacity of the map is reached an old entry
* will be deleted (the delete callback will be called).
*/
boolean
util_keymap_insert(struct keymap *map, const void *key,
const void *data, void *user)
{
unsigned key_hash;
struct keymap_item *item;
struct cso_hash_iter iter;
if (!map)
return FALSE;
key_hash = hash(key, map->key_size);
item = hash_table_find_item(map, key, key_hash);
if (item) {
/* call delete callback for old entry/item */
map->delete_func(map, item->key, item->value, user);
item->value = (void *) data;
return TRUE;
}
item = MALLOC_STRUCT(keymap_item);
if (!item)
return FALSE;
item->key = mem_dup(key, map->key_size);
item->value = (void *) data;
iter = cso_hash_insert(map->cso, key_hash, item);
if (cso_hash_iter_is_null(iter)) {
FREE(item);
return FALSE;
}
map->num_entries++;
return TRUE;
}
/**
* Look up a key in the map and return the associated data pointer.
*/
const void *
util_keymap_lookup(const struct keymap *map, const void *key)
{
unsigned key_hash;
struct keymap_item *item;
if (!map)
return NULL;
key_hash = hash(key, map->key_size);
item = hash_table_find_item(map, key, key_hash);
if (!item)
return NULL;
return item->value;
}
/**
* Remove an entry from the map.
* The delete callback will be called if the given key/entry is found.
* \param user passed to the delete callback as the last param.
*/
void
util_keymap_remove(struct keymap *map, const void *key, void *user)
{
unsigned key_hash;
struct cso_hash_iter iter;
struct keymap_item *item;
if (!map)
return;
key_hash = hash(key, map->key_size);
iter = hash_table_find_iter(map, key, key_hash);
if (cso_hash_iter_is_null(iter))
return;
item = hash_table_item(iter);
if (!item)
return;
map->delete_func(map, item->key, item->value, user);
FREE(item->key);
FREE(item);
map->num_entries--;
cso_hash_erase(map->cso, iter);
}
/**
* Remove all entries from the map, calling the delete callback for each.
* \param user passed to the delete callback as the last param.
*/
void
util_keymap_remove_all(struct keymap *map, void *user)
{
struct cso_hash_iter iter;
struct keymap_item *item;
if (!map)
return;
iter = cso_hash_first_node(map->cso);
while (!cso_hash_iter_is_null(iter)) {
item = (struct keymap_item *)
cso_hash_take(map->cso, cso_hash_iter_key(iter));
map->delete_func(map, item->key, item->value, user);
FREE(item->key);
FREE(item);
iter = cso_hash_first_node(map->cso);
}
}
extern void
util_keymap_info(const struct keymap *map)
{
debug_printf("Keymap %p: %u of max %u entries\n",
(void *) map, map->num_entries, map->max_entries);
}