gallium: General purpose hash table, which is actually just a convenient frontend to cso_hash.

4 files changed, 287 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/util/Makefile b/src/gallium/auxiliary/util/Makefile
index 2abbe9500ec..2016c6fb1f7 100644
--- a/src/gallium/auxiliary/util/Makefile
+++ b/src/gallium/auxiliary/util/Makefile
@@ -8,6 +8,7 @@ C_SOURCES = \
 	p_tile.c \
 	p_util.c \
 	u_handle_table.c \
+	u_hash_table.c \
 	u_mm.c \
 	u_snprintf.c
 
diff --git a/src/gallium/auxiliary/util/SConscript b/src/gallium/auxiliary/util/SConscript
index 2030214aa7e..154a3eca8cc 100644
--- a/src/gallium/auxiliary/util/SConscript
+++ b/src/gallium/auxiliary/util/SConscript
@@ -7,6 +7,7 @@ util = env.ConvenienceLibrary(
 		'p_tile.c',
 		'p_util.c',
 		'u_handle_table.c',
+		'u_hash_table.c',
 		'u_mm.c',
 		'u_snprintf.c',
 	])
diff --git a/src/gallium/auxiliary/util/u_hash_table.c b/src/gallium/auxiliary/util/u_hash_table.c
new file mode 100644
index 00000000000..ac2cb1b540d
--- /dev/null
+++ b/src/gallium/auxiliary/util/u_hash_table.c
@@ -0,0 +1,199 @@
+/**************************************************************************
+ *
+ * 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 <[email protected]>
+ */
+
+
+#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);
+}
+
diff --git a/src/gallium/auxiliary/util/u_hash_table.h b/src/gallium/auxiliary/util/u_hash_table.h
new file mode 100644
index 00000000000..d941f2c6b16
--- /dev/null
+++ b/src/gallium/auxiliary/util/u_hash_table.h
@@ -0,0 +1,86 @@
+/**************************************************************************
+ *
+ * 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 <[email protected]>
+ */
+
+#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_ */