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diff --git a/include/util/hash_table.h b/include/util/hash_table.h
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+/*
+ * 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 <stdlib.h>
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include "sqfs/predef.h"
+
+struct hash_entry {
+   sqfs_u32 hash;
+   const void *key;
+   void *data;
+};
+
+struct hash_table {
+   struct hash_entry *table;
+   sqfs_u32 (*key_hash_function)(void *user, const void *key);
+   bool (*key_equals_function)(void *user, const void *a, const void *b);
+   const void *deleted_key;
+   void *user;
+   sqfs_u32 size;
+   sqfs_u32 rehash;
+   sqfs_u64 size_magic;
+   sqfs_u64 rehash_magic;
+   sqfs_u32 max_entries;
+   sqfs_u32 size_index;
+   sqfs_u32 entries;
+   sqfs_u32 deleted_entries;
+};
+
+SQFS_INTERNAL struct hash_table *
+hash_table_create(sqfs_u32 (*key_hash_function)(void *user, const void *key),
+                  bool (*key_equals_function)(void *user, const void *a,
+                                              const void *b));
+
+SQFS_INTERNAL struct hash_table *
+hash_table_clone(struct hash_table *src);
+
+SQFS_INTERNAL void
+hash_table_destroy(struct hash_table *ht,
+		   void (*delete_function)(struct hash_entry *entry));
+
+SQFS_INTERNAL struct hash_entry *
+hash_table_insert_pre_hashed(struct hash_table *ht, sqfs_u32 hash,
+                             const void *key, void *data);
+
+SQFS_INTERNAL struct hash_entry *
+hash_table_search_pre_hashed(struct hash_table *ht, sqfs_u32 hash,
+                             const void *key);
+
+SQFS_INTERNAL struct hash_entry *hash_table_next_entry(struct hash_table *ht,
+						       struct hash_entry *entry);
+
+/**
+ * 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 (struct hash_entry *entry = hash_table_next_entry(ht, NULL);  \
+        entry != NULL;                                                     \
+        entry = hash_table_next_entry(ht, entry))
+
+#endif /* _HASH_TABLE_H */