--- /dev/null
+/**************************************************************************
+ *
+ * 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.
+ *
+ **************************************************************************/
+
+/**
+ * @file
+ * General purpose hash table implementation.
+ *
+ * Just uses the cso_hash for now, but it might be better switch to a linear
+ * probing hash table implementation at some point -- as it is said they have
+ * better lookup and cache performance and it appears to be possible to write
+ * a lock-free implementation of such hash tables .
+ *
+ * @author José Fonseca <jrfonseca@tungstengraphics.com>
+ */
+
+
+#include "pipe/p_compiler.h"
+#include "pipe/p_debug.h"
+#include "pipe/p_util.h"
+
+#include "cso_cache/cso_hash.h"
+#include "u_hash_table.h"
+
+
+struct hash_table
+{
+ struct cso_hash *cso;
+
+ /** Hash function */
+ unsigned (*hash)(void *key);
+
+ /** Compare two keys */
+ int (*compare)(void *key1, void *key2);
+
+ /* TODO: key, value destructors? */
+};
+
+
+struct hash_table_item
+{
+ void *key;
+ void *value;
+};
+
+
+struct hash_table *
+hash_table_create(unsigned (*hash)(void *key),
+ int (*compare)(void *key1, void *key2))
+{
+ struct hash_table *ht;
+
+ ht = MALLOC_STRUCT(hash_table);
+ if(!ht)
+ return NULL;
+
+ ht->cso = cso_hash_create();
+ if(!ht->cso) {
+ FREE(ht);
+ return NULL;
+ }
+
+ ht->hash = hash;
+ ht->compare = compare;
+
+ return ht;
+}
+
+
+static struct hash_table_item *
+hash_table_find_item(struct hash_table *ht,
+ void *key,
+ unsigned key_hash)
+{
+ struct cso_hash_iter iter;
+ struct hash_table_item *item;
+
+ iter = cso_hash_find(ht->cso, key_hash);
+ while (!cso_hash_iter_is_null(iter)) {
+ item = (struct hash_table_item *)cso_hash_iter_data(iter);
+ if (!ht->compare(item->key, key))
+ return item;
+ iter = cso_hash_iter_next(iter);
+ }
+
+ return NULL;
+}
+
+
+enum pipe_error
+hash_table_set(struct hash_table *ht,
+ void *key,
+ void *value)
+{
+ unsigned key_hash;
+ struct hash_table_item *item;
+
+ assert(ht);
+
+ key_hash = ht->hash(key);
+
+ item = hash_table_find_item(ht, key, key_hash);
+ if(item) {
+ /* TODO: key/value destruction? */
+ item->value = value;
+ return PIPE_OK;
+ }
+
+ item = MALLOC_STRUCT(hash_table_item);
+ if(!item)
+ return PIPE_ERROR_OUT_OF_MEMORY;
+
+ item->key = key;
+ item->value = value;
+
+ cso_hash_insert(ht->cso, key_hash, item);
+ /* FIXME: there is no OOM propagation in cso_hash */
+ if(0) {
+ FREE(item);
+ return PIPE_ERROR_OUT_OF_MEMORY;
+ }
+
+ return PIPE_OK;
+}
+
+
+void *
+hash_table_get(struct hash_table *ht,
+ void *key)
+{
+ unsigned key_hash;
+ struct hash_table_item *item;
+
+ assert(ht);
+
+ key_hash = ht->hash(key);
+
+ item = hash_table_find_item(ht, key, key_hash);
+ if(!item)
+ return NULL;
+
+ return item->value;
+}
+
+
+void
+hash_table_remove(struct hash_table *ht,
+ void *key)
+{
+ unsigned key_hash;
+ struct hash_table_item *item;
+
+ assert(ht);
+
+ key_hash = ht->hash(key);
+
+ item = hash_table_find_item(ht, key, key_hash);
+ if(!item)
+ return;
+
+ /* FIXME: cso_hash_take takes the first element of the collision list
+ * indiscriminately, so we can not take the item down. */
+ item->value = NULL;
+}
+
+
+void
+hash_table_destroy(struct hash_table *ht)
+{
+ assert(ht);
+
+ cso_hash_delete(ht->cso);
+
+ FREE(ht);
+}
+
--- /dev/null
+/**************************************************************************
+ *
+ * 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.
+ *
+ **************************************************************************/
+
+/**
+ * General purpose hash table.
+ *
+ * @author José Fonseca <jrfonseca@tungstengraphics.com>
+ */
+
+#ifndef U_HASH_TABLE_H_
+#define U_HASH_TABLE_H_
+
+
+#include "pipe/p_error.h"
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/**
+ * Generic purpose hash table.
+ */
+struct hash_table;
+
+
+/**
+ * Create an hash table.
+ *
+ * @param hash hash function
+ * @param compare should return 0 for two equal keys.
+ */
+struct hash_table *
+hash_table_create(unsigned (*hash)(void *key),
+ int (*compare)(void *key1, void *key2));
+
+
+enum pipe_error
+hash_table_set(struct hash_table *ht,
+ void *key,
+ void *value);
+
+void *
+hash_table_get(struct hash_table *ht,
+ void *key);
+
+
+void
+hash_table_remove(struct hash_table *ht,
+ void *key);
+
+
+void
+hash_table_destroy(struct hash_table *ht);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* U_HASH_TABLE_H_ */
projects / mesa.git / commitdiff