summaryrefslogtreecommitdiff
path: root/libc/sysdeps
diff options
context:
space:
mode:
Diffstat (limited to 'libc/sysdeps')
-rw-r--r--libc/sysdeps/linux/common/Makefile3
-rw-r--r--libc/sysdeps/linux/common/cmsg_nxthdr.c39
2 files changed, 41 insertions, 1 deletions
diff --git a/libc/sysdeps/linux/common/Makefile b/libc/sysdeps/linux/common/Makefile
index 0b387587d..34e4de015 100644
--- a/libc/sysdeps/linux/common/Makefile
+++ b/libc/sysdeps/linux/common/Makefile
@@ -26,7 +26,8 @@ include $(TOPDIR)Rules.mak
CSRC= waitpid.c kernel_version.c statfix.c getdnnm.c gethstnm.c \
mkfifo.c setegid.c wait.c errno.c getpagesize.c seteuid.c \
- wait3.c setpgrp.c getdtablesize.c create_module.c ptrace.c
+ wait3.c setpgrp.c getdtablesize.c create_module.c ptrace.c \
+ cmsg_nxthdr.c
COBJS=$(patsubst %.c,%.o, $(CSRC))
MSRC=syscalls.c
diff --git a/libc/sysdeps/linux/common/cmsg_nxthdr.c b/libc/sysdeps/linux/common/cmsg_nxthdr.c
new file mode 100644
index 000000000..fda37f37a
--- /dev/null
+++ b/libc/sysdeps/linux/common/cmsg_nxthdr.c
@@ -0,0 +1,39 @@
+/* Return point to next ancillary data entry in message header.
+ Copyright (C) 1997, 1998 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <sys/socket.h>
+
+
+struct cmsghdr *
+__cmsg_nxthdr (struct msghdr *mhdr, struct cmsghdr *cmsg)
+{
+ if ((size_t) cmsg->cmsg_len < sizeof (struct cmsghdr))
+ /* The kernel header does this so there may be a reason. */
+ return NULL;
+
+ cmsg = (struct cmsghdr *) ((unsigned char *) cmsg
+ + CMSG_ALIGN (cmsg->cmsg_len));
+ if ((unsigned char *) (cmsg + 1) >= ((unsigned char *) mhdr->msg_control
+ + mhdr->msg_controllen)
+ || ((unsigned char *) cmsg + CMSG_ALIGN (cmsg->cmsg_len)
+ >= ((unsigned char *) mhdr->msg_control + mhdr->msg_controllen)))
+ /* No more entries. */
+ return NULL;
+ return cmsg;
+}