diff options
Diffstat (limited to 'sys/contrib/ngatm/netnatm/misc/unimsg_common.c')
-rw-r--r-- | sys/contrib/ngatm/netnatm/misc/unimsg_common.c | 54 |
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); +} |