util: Move the open-addressing linear-probing hash_table to src/util.

This hash table is used in core Mesa, the GLSL compiler, and the i965
driver, which makes it a good candidate for the new src/util module.

It's much faster than program/hash_table.[ch] (see commit 6991c2922f5
for data), and José's u_hash_table.c has a comment saying Gallium should
probably consider switching to a linear probing hash table at some point.
So this seems like the best candidate for a shared data structure.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>

v2 (Jason Ekstrand): Pick up another hash_table use and patch up scons

Signed-off-by: Jason Ekstrand <jason.ekstrand@intel.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

1 files changed, 106 insertions, 0 deletions

diff --git a/src/util/hash_table.h b/src/util/hash_table.h
new file mode 100644
index 0000000..5fa5899
--- /dev/null
+++ b/src/util/hash_table.h
@@ -0,0 +1,106 @@
+/*
+ * Copyright © 2009,2012 Intel Corporation
+ *
+ * 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, sublicense,
+ * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Authors:
+ *    Eric Anholt <eric@anholt.net>
+ *
+ */
+
+#ifndef _HASH_TABLE_H
+#define _HASH_TABLE_H
+
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include "main/compiler.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct hash_entry {
+   uint32_t hash;
+   const void *key;
+   void *data;
+};
+
+struct hash_table {
+   struct hash_entry *table;
+   bool (*key_equals_function)(const void *a, const void *b);
+   const void *deleted_key;
+   uint32_t size;
+   uint32_t rehash;
+   uint32_t max_entries;
+   uint32_t size_index;
+   uint32_t entries;
+   uint32_t deleted_entries;
+};
+
+struct hash_table *
+_mesa_hash_table_create(void *mem_ctx,
+                        bool (*key_equals_function)(const void *a,
+                                                    const void *b));
+void _mesa_hash_table_destroy(struct hash_table *ht,
+                              void (*delete_function)(struct hash_entry *entry));
+void _mesa_hash_table_set_deleted_key(struct hash_table *ht,
+                                      const void *deleted_key);
+
+struct hash_entry *
+_mesa_hash_table_insert(struct hash_table *ht, uint32_t hash,
+                        const void *key, void *data);
+struct hash_entry *
+_mesa_hash_table_search(struct hash_table *ht, uint32_t hash,
+                        const void *key);
+void _mesa_hash_table_remove(struct hash_table *ht,
+                             struct hash_entry *entry);
+
+struct hash_entry *_mesa_hash_table_next_entry(struct hash_table *ht,
+                                               struct hash_entry *entry);
+struct hash_entry *
+_mesa_hash_table_random_entry(struct hash_table *ht,
+                              bool (*predicate)(struct hash_entry *entry));
+
+uint32_t _mesa_hash_data(const void *data, size_t size);
+uint32_t _mesa_hash_string(const char *key);
+bool _mesa_key_string_equal(const void *a, const void *b);
+bool _mesa_key_pointer_equal(const void *a, const void *b);
+
+static inline uint32_t _mesa_hash_pointer(const void *pointer)
+{
+   return _mesa_hash_data(&pointer, sizeof(pointer));
+}
+
+/**
+ * This foreach function is safe against deletion (which just replaces
+ * an entry's data with the deleted marker), but not against insertion
+ * (which may rehash the table, making entry a dangling pointer).
+ */
+#define hash_table_foreach(ht, entry)                   \
+   for (entry = _mesa_hash_table_next_entry(ht, NULL);  \
+        entry != NULL;                                  \
+        entry = _mesa_hash_table_next_entry(ht, entry))
+
+#ifdef __cplusplus
+} /* extern C */
+#endif
+
+#endif /* _HASH_TABLE_H */