X-Git-Url: https://git.distorted.org.uk/~mdw/secnet/blobdiff_plain/ae5ae3bf5c5709938e3a2bb6203094ede8af45e6..1fc8a4acb3ef658696038c9c4bd3c155fbc27ac3:/util.h

diff --git a/util.h b/util.h
index 63ceef6..4e1f9d0 100644
--- a/util.h
+++ b/util.h
@@ -1,3 +1,22 @@
+/*
+ * This file is part of secnet.
+ * See README for full list of copyright holders.
+ *
+ * secnet 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 d of the License, or
+ * (at your option) any later version.
+ *
+ * secnet 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
+ * version 3 along with secnet; if not, see
+ * https://www.gnu.org/licenses/gpl.html.
+ */
+
 #ifndef util_h
 #define util_h
 
@@ -89,6 +108,21 @@ void string_item_to_iaddr(const item_t *item, uint16_t port, union iaddr *ia,
 			  const char *desc);
 
 
+/*
+ * SBUF_DEFINE(int nbufs, size_t size);
+ *   // Generates a number of definitions and statements organising
+ *   // nbufs rotating char[size] buffers such that subsequent code
+ *   // may refer to:
+ * char *const SBUF;
+ */
+#define SBUF_DEFINE(nbufs, size)			\
+    static int static_bufs__bufnum;			\
+    static char static_bufs__bufs[(nbufs)][(size)];	\
+    static_bufs__bufnum++;				\
+    static_bufs__bufnum %= (nbufs);			\
+    static_bufs__bufs[static_bufs__bufnum]
+#define SBUF (static_bufs__bufs[static_bufs__bufnum])
+
 /*----- line-buffered asynch input -----*/
 
 enum async_linebuf_result {