1 files changed, 54 insertions, 0 deletions
diff --git a/sys/contrib/ngatm/netnatm/misc/unimsg_common.c b/sys/contrib/ngatm/netnatm/misc/unimsg_common.c
new file mode 100644
index 0000000..033213a
--- /dev/null
+++ b/sys/contrib/ngatm/netnatm/misc/unimsg_common.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2003-2003
+ *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
+ * 	All rights reserved.
+ *
+ * Author: Hartmut Brandt <harti@freebsd.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Begemot: libunimsg/netnatm/misc/unimsg_common.c,v 1.3 2004/07/08 08:22:03 brandt Exp $
+ */
+
+#include <netnatm/unimsg.h>
+
+/*
+ * Make sure there is enough space in front of the data for
+ * len bytes, and update the read pointer.
+ */
+int
+uni_msg_prepend(struct uni_msg *msg, size_t len)
+{
+	size_t need;
+
+	if (uni_msg_leading(msg) >= len) {
+		msg->b_rptr -= len;
+		return (0);
+	}
+	need = len - uni_msg_leading(msg);
+	if (uni_msg_ensure(msg, need))
+		return (-1);
+	memcpy(msg->b_rptr + need, msg->b_rptr, uni_msg_len(msg));
+	msg->b_rptr += need - len;
+	msg->b_wptr += need;
+	return (0);
+}