Initial import

[samba] / source / include / dlinklist.h

diff --git a/source/include/dlinklist.h b/source/include/dlinklist.h
new file mode 100644 (file)
index 0000000..c856aaa
--- /dev/null
+++ b/source/include/dlinklist.h
@@ -0,0 +1,92 @@
+/* 
+   Unix SMB/CIFS implementation.
+   some simple double linked list macros
+   Copyright (C) Andrew Tridgell 1998
+   
+   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.
+*/
+
+/* To use these macros you must have a structure containing a next and
+   prev pointer */
+
+
+/* hook into the front of the list */
+#define DLIST_ADD(list, p) \
+{ \
+        if (!(list)) { \
+               (list) = (p); \
+               (p)->next = (p)->prev = NULL; \
+       } else { \
+               (list)->prev = (p); \
+               (p)->next = (list); \
+               (p)->prev = NULL; \
+               (list) = (p); \
+       }\
+}
+
+/* remove an element from a list - element doesn't have to be in list. */
+#define DLIST_REMOVE(list, p) \
+{ \
+       if ((p) == (list)) { \
+               (list) = (p)->next; \
+               if (list) (list)->prev = NULL; \
+       } else { \
+               if ((p)->prev) (p)->prev->next = (p)->next; \
+               if ((p)->next) (p)->next->prev = (p)->prev; \
+       } \
+       if ((p) && ((p) != (list))) (p)->next = (p)->prev = NULL; \
+}
+
+/* promote an element to the top of the list */
+#define DLIST_PROMOTE(list, p) \
+{ \
+          DLIST_REMOVE(list, p) \
+          DLIST_ADD(list, p) \
+}
+
+/* hook into the end of the list - needs a tmp pointer */
+#define DLIST_ADD_END(list, p, tmp) \
+{ \
+               if (!(list)) { \
+                       (list) = (p); \
+                       (p)->next = (p)->prev = NULL; \
+               } else { \
+                       for ((tmp) = (list); (tmp)->next; (tmp) = (tmp)->next) ; \
+                       (tmp)->next = (p); \
+                       (p)->next = NULL; \
+                       (p)->prev = (tmp); \
+               } \
+}
+
+/* insert 'p' after the given element 'el' in a list. If el is NULL then
+   this is the same as a DLIST_ADD() */
+#define DLIST_ADD_AFTER(list, p, el) \
+do { \
+        if (!(list) || !(el)) { \
+               DLIST_ADD(list, p); \
+       } else { \
+               p->prev = el; \
+               p->next = el->next; \
+               el->next = p; \
+               if (p->next) p->next->prev = p; \
+       }\
+} while (0)
+
+/* demote an element to the top of the list, needs a tmp pointer */
+#define DLIST_DEMOTE(list, p, tmp) \
+{ \
+               DLIST_REMOVE(list, p) \
+               DLIST_ADD_END(list, p, tmp) \
+}