diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/cmsg_nxthdr.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/cmsg_nxthdr.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/cmsg_nxthdr.c b/sysdeps/unix/sysv/linux/cmsg_nxthdr.c new file mode 100644 index 0000000000..2245db7f25 --- /dev/null +++ b/sysdeps/unix/sysv/linux/cmsg_nxthdr.c @@ -0,0 +1,38 @@ +/* Return point to next ancillary data entry in message header. + Copyright (C) 1997 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) +{ + unsigned char *p; + + if ((size_t) cmsg->cmsg_len < sizeof (struct cmsghdr)) + /* The kernel header does this so there may be a reason. */ + return NULL; + + p = (((unsigned char *) cmsg) + + ((cmsg->cmsg_len + sizeof (long int) - 1) & ~sizeof (long int))); + if (p >= (unsigned char *) mhdr->msg_control + mhdr->msg_controllen) + /* No more entries. */ + return NULL; + return (struct cmsghdr *) p; +} |