dliste.h copied from epithet and DLIST2_PREPEND added

diff --git a/hostside/dliste.h b/hostside/dliste.h
new file mode 100644 (file)
index 0000000..72a235c
--- /dev/null
+++ b/hostside/dliste.h
@@ -0,0 +1,65 @@
+/*
+ * dlist.h
+ * Doubly linked lists
+ *
+ * This file is part of epithet, a DNS nameserver.
+ * epithet is Copyright 2001 Ian Jackson.
+ *
+ * epithet 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 and documentation 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 epithet; if not, write to the Free Software Foundation,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA, or email
+ * epithet-maint@chiark.greenend.org.uk.
+ */
+
+#ifndef DLIST_H
+#define DLIST_H
+
+
+#define DLIST_NNODE(nodetype,linktag) struct linktag { nodetype *next, *back; }
+#define DLIST_NODE(nodetype)          DLIST_NNODE(nodetype, )
+
+#define DLIST1_PREPEND(head,node,linkmemb)                                    \
+  ((void)((node)->linkmemb.next= (head),                                     \
+         (node)->linkmemb.back= 0,                                           \
+         ((head) ? (head)->linkmemb.back= (node) : 0),                       \
+         (head)= (node)))
+
+#define DLIST1_REMOVE(head,node,link)                                        \
+  ((void)                                                                    \
+   ((node)->link.next ? ((node)->link.next->link.back= (node)->link.back) :0, \
+    (node)->link.back ? ((node)->link.back->link.next= (node)->link.next)     \
+                      : ((head)=                       (node)->link.next)))
+
+
+#define DLIST2_NHEAD(nodetype,listtag) struct listtag { nodetype *head,*tail; }
+#define DLIST2_HEAD(nodetype)          DLIST2_NHEAD(nodetype, )
+
+#define DLIST2_INIT(list) ((list).head= (list).tail= 0)
+
+#define DLIST2_REMOVE(list,node,link)                                        \
+  ((void)                                                                    \
+   (((node)->link.back ? ((node)->link.back->link.next= (node)->link.next)    \
+                       : (                 (list).head= (node)->link.next)),  \
+    ((node)->link.next ? ((node)->link.next->link.back= (node)->link.back)    \
+                       : (                 (list).tail= (node)->link.back))))
+
+#define DLIST2_APPEND(list,node,link)                  \
+  ((void)                                              \
+   ((node)->link.next= 0,                              \
+    (node)->link.back= (list).tail,                    \
+    ((list).tail ? ((list).tail->link.next= (node))    \
+                 : ((list).head= (node))),             \
+    (list).tail= (node)))
+
+     
+#endif /*DLIST_H*/