mesa: add set support (stores a set of pointers)

From: git://people.freedesktop.org/~anholt/hash_table

Reviewed-by: Jordan Justen <[email protected]>
[[email protected]: minor rework for mesa]
Signed-off-by: Jordan Justen <[email protected]>
Reviewed-by: Brian Paul <[email protected]>

1 files changed, 94 insertions, 0 deletions

diff --git a/src/mesa/main/set.h b/src/mesa/main/set.h
new file mode 100644
index 00000000000..206d0c4d24f
--- /dev/null
+++ b/src/mesa/main/set.h
@@ -0,0 +1,94 @@
+/*
+ * 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 <[email protected]>
+ *
+ */
+
+#ifndef _SET_H
+#define _SET_H
+
+#include <inttypes.h>
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct set_entry {
+   uint32_t hash;
+   const void *key;
+};
+
+struct set {
+   void *mem_ctx;
+   struct set_entry *table;
+   bool (*key_equals_function)(const void *a, const void *b);
+   uint32_t size;
+   uint32_t rehash;
+   uint32_t max_entries;
+   uint32_t size_index;
+   uint32_t entries;
+   uint32_t deleted_entries;
+};
+
+struct set *
+_mesa_set_create(void *mem_ctx,
+                 bool (*key_equals_function)(const void *a,
+                                             const void *b));
+void
+_mesa_set_destroy(struct set *set,
+                  void (*delete_function)(struct set_entry *entry));
+
+struct set_entry *
+_mesa_set_add(struct set *set, uint32_t hash, const void *key);
+
+struct set_entry *
+_mesa_set_search(const struct set *set, uint32_t hash,
+                 const void *key);
+
+void
+_mesa_set_remove(struct set *set, struct set_entry *entry);
+
+struct set_entry *
+_mesa_set_next_entry(const struct set *set, struct set_entry *entry);
+
+struct set_entry *
+_mesa_set_random_entry(struct set *set,
+                       int (*predicate)(struct set_entry *entry));
+
+/**
+ * This foreach function is safe against deletion, but not against
+ * insertion (which may rehash the set, making entry a dangling
+ * pointer).
+ */
+#define set_foreach(set, entry)                          \
+   for (entry = _mesa_set_next_entry(set, NULL);  \
+        entry != NULL;                                   \
+        entry = _mesa_set_next_entry(set, entry))
+
+#ifdef __cplusplus
+} /* extern C */
+#endif
+
+#endif /* _SET_H */