1 files changed, 261 insertions, 0 deletions
diff --git a/source4/lib/json/linkhash.h b/source4/lib/json/linkhash.h
new file mode 100644
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+++ b/source4/lib/json/linkhash.h
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+/*
+ * $Id: linkhash.h,v 1.6 2006/01/30 23:07:57 mclark Exp $
+ *
+ * Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd.
+ * Michael Clark <michael@metaparadigm.com>
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See COPYING for details.
+ *
+ */
+ 
+#ifndef _linkhash_h_
+#define _linkhash_h_
+
+/**
+ * golden prime used in hash functions
+ */
+#define LH_PRIME 0x9e370001UL
+
+/**
+ * sentinel pointer value for empty slots
+ */
+#define LH_EMPTY (void*)-1
+
+/**
+ * sentinel pointer value for freed slots
+ */
+#define LH_FREED (void*)-2
+
+struct lh_entry;
+
+/**
+ * callback function prototypes
+ */
+typedef void (lh_entry_free_fn) (struct lh_entry *e);
+/**
+ * callback function prototypes
+ */
+typedef unsigned long (lh_hash_fn) (void *k);
+/**
+ * callback function prototypes
+ */
+typedef int (lh_equal_fn) (void *k1, void *k2);
+
+/**
+ * An entry in the hash table
+ */
+struct lh_entry {
+	/**
+	 * The key.
+	 */
+	void *k;
+	/**
+	 * The value.
+	 */
+	void *v;
+	/**
+	 * The next entry
+	 */
+	struct lh_entry *next;
+	/**
+	 * The previous entry.
+	 */
+	struct lh_entry *prev;
+};
+
+
+/**
+ * The hash table structure.
+ */
+struct lh_table {
+	/**
+	 * Size of our hash.
+	 */
+	int size;
+	/**
+	 * Numbers of entries.
+	 */
+	int count;
+
+	/**
+	 * Number of collisions.
+	 */
+	int collisions;
+
+	/**
+	 * Number of resizes.
+	 */
+	int resizes;
+
+	/**
+	 * Number of lookups.
+	 */
+	int lookups;
+
+	/**
+	 * Number of inserts.
+	 */
+	int inserts;
+
+	/**
+	 * Number of deletes.
+	 */
+	int deletes;
+
+	/**
+	 * Name of the hash table.
+	 */
+	char *name;
+
+	/**
+	 * The first entry.
+	 */
+	struct lh_entry *head;
+
+	/**
+	 * The last entry.
+	 */
+	struct lh_entry *tail;
+
+	struct lh_entry *table;
+
+	/**
+	 * A pointer onto the function responsible for freeing an entry.
+	 */
+	lh_entry_free_fn *free_fn;
+	lh_hash_fn *hash_fn;
+	lh_equal_fn *equal_fn;
+};
+
+
+/**
+ * Pre-defined hash and equality functions
+ */
+extern unsigned long lh_ptr_hash(void *k);
+extern int lh_ptr_equal(void *k1, void *k2);
+
+extern unsigned long lh_char_hash(void *k);
+extern int lh_char_equal(void *k1, void *k2);
+
+
+/**
+ * Convenience list iterator.
+ */
+#define lh_foreach(table, entry) \
+for(entry = table->head; entry; entry = entry->next)
+
+/**
+ * lh_foreach_safe allows calling of deletion routine while iterating.
+ */
+#define lh_foreach_safe(table, entry, tmp) \
+for(entry = table->head; entry && ((tmp = entry->next) || 1); entry = tmp)
+
+
+
+/**
+ * Create a new linkhash table.
+ * @param size initial table size. The table is automatically resized
+ * although this incurs a performance penalty.
+ * @param name the table name.
+ * @param free_fn callback function used to free memory for entries
+ * when lh_table_free or lh_table_delete is called.
+ * If NULL is provided, then memory for keys and values
+ * must be freed by the caller.
+ * @param hash_fn  function used to hash keys. 2 standard ones are defined:
+ * lh_ptr_hash and lh_char_hash for hashing pointer values
+ * and C strings respectively.
+ * @param equal_fn comparison function to compare keys. 2 standard ones defined:
+ * lh_ptr_hash and lh_char_hash for comparing pointer values
+ * and C strings respectively.
+ * @return a pointer onto the linkhash table.
+ */
+extern struct lh_table* lh_table_new(int size, char *name,
+				     lh_entry_free_fn *free_fn,
+				     lh_hash_fn *hash_fn,
+				     lh_equal_fn *equal_fn);
+
+/**
+ * Convenience function to create a new linkhash
+ * table with char keys.
+ * @param size initial table size.
+ * @param name table name.
+ * @param free_fn callback function used to free memory for entries.
+ * @return a pointer onto the linkhash table.
+ */
+extern struct lh_table* lh_kchar_table_new(int size, char *name,
+					   lh_entry_free_fn *free_fn);
+
+
+/**
+ * Convenience function to create a new linkhash
+ * table with ptr keys.
+ * @param size initial table size.
+ * @param name table name.
+ * @param free_fn callback function used to free memory for entries.
+ * @return a pointer onto the linkhash table.
+ */
+extern struct lh_table* lh_kptr_table_new(int size, char *name,
+					  lh_entry_free_fn *free_fn);
+
+
+/**
+ * Free a linkhash table.
+ * If a callback free function is provided then it is called for all
+ * entries in the table.
+ * @param t table to free.
+ */
+extern void lh_table_free(struct lh_table *t);
+
+
+/**
+ * Insert a record into the table.
+ * @param t the table to insert into.
+ * @param k a pointer to the key to insert.
+ * @param v a pointer to the value to insert.
+ */
+extern int lh_table_insert(struct lh_table *t, void *k, void *v);
+
+
+/**
+ * Lookup a record into the table.
+ * @param t the table to lookup
+ * @param k a pointer to the key to lookup
+ * @return a pointer to the record structure of the value or NULL if it does not exist.
+ */
+extern struct lh_entry* lh_table_lookup_entry(struct lh_table *t, void *k);
+
+/**
+ * Lookup a record into the table
+ * @param t the table to lookup
+ * @param k a pointer to the key to lookup
+ * @return a pointer to the found value or NULL if it does not exist.
+ */
+extern void* lh_table_lookup(struct lh_table *t, void *k);
+
+
+/**
+ * Delete a record from the table.
+ * If a callback free function is provided then it is called for the
+ * for the item being deleted.
+ * @param t the table to delete from.
+ * @param e a pointer to the entry to delete.
+ * @return 0 if the item was deleted.
+ * @return -1 if it was not found.
+ */
+extern int lh_table_delete_entry(struct lh_table *t, struct lh_entry *e);
+
+
+/**
+ * Delete a record from the table.
+ * If a callback free function is provided then it is called for the
+ * for the item being deleted.
+ * @param t the table to delete from.
+ * @param k a pointer to the key to delete.
+ * @return 0 if the item was deleted.
+ * @return -1 if it was not found.
+ */
+extern int lh_table_delete(struct lh_table *t, void *k);
+
+
+#endif