Added hash-based stat cache code from Ying Chen.

Jeremy.
(This used to be commit b62a1bd6328f5894ae1a2fef3ef6fc66304ade52)

1 files changed, 75 insertions, 0 deletions

diff --git a/source3/include/hash.h b/source3/include/hash.h
new file mode 100644
index 0000000000..2de7031855
--- /dev/null
+++ b/source3/include/hash.h
@@ -0,0 +1,75 @@
+/* 
+   Unix SMB/Netbios implementation.
+   Version 2.0
+
+   Copyright (C) Ying Chen 2000.
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef	_HASH_H_
+#define	_HASH_H_
+
+#define MAX_HASH_TABLE_SIZE    32768
+#define HASH_TABLE_INCREMENT  2
+
+typedef int (*compare_function)(char *, char *);
+typedef int (*hash_function)(int, char *);
+
+/*
+ * lru_link: links the node to the LRU list.
+ * hash_elem: the pointer to the element that is tied onto the link.
+ */
+typedef struct lru_node {
+        ubi_dlNode lru_link;
+        void *hash_elem;
+} lru_node;
+
+/* 
+ * bucket_link: link the hash element to the bucket chain that it belongs to.
+ * lru_link: this element ties the hash element to the lru list. 
+ * bucket: a pointer to the hash bucket that this element belongs to.
+ * value: a pointer to the hash element content. It can be anything.
+ * key: stores the string key. The hash_element is always allocated with
+ * more memory space than the structure shown below to accomodate the space
+ * used for the whole string. But the memory is always appended at the 
+ * end of the structure, so keep "key" at the end of the structure.
+ * Don't move it.
+ */
+typedef struct hash_element {
+        ubi_dlNode	bucket_link;          
+        lru_node    lru_link;
+        ubi_dlList	*bucket;
+        void	*value;		
+        char key[1];	
+} hash_element;
+
+/*
+ * buckets: a list of buckets, implemented as a dLinkList. 
+ * lru_chain: the lru list of all the hash elements. 
+ * num_elements: the # of elements in the hash table.
+ * size: the hash table size.
+ * comp_func: the compare function used during hash key comparisons.
+ */
+
+typedef struct hash_table {
+        ubi_dlList      *buckets;
+        ubi_dlList      lru_chain;     
+        int     num_elements;	
+        int     size;
+        compare_function        comp_func; 
+} hash_table;
+
+#endif /* _HASH_H_ */