diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/preadv2.c')
-rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/preadv2.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/preadv2.c b/REORG.TODO/sysdeps/unix/sysv/linux/preadv2.c new file mode 100644 index 0000000000..11fe85eaa8 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/preadv2.c @@ -0,0 +1,55 @@ +/* Linux implementation of preadv2. + Copyright (C) 2017 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 Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <sys/uio.h> +#include <sysdep-cancel.h> + +#ifndef __OFF_T_MATCHES_OFF64_T + +# if !defined (__NR_preadv2) && defined (__NR_pread64v2) +# define __NR_preadv2 __NR_pread64v2 +# endif + +ssize_t +preadv2 (int fd, const struct iovec *vector, int count, off_t offset, + int flags) +{ +# ifdef __NR_preadv2 + ssize_t result = SYSCALL_CANCEL (preadv2, fd, vector, count, + LO_HI_LONG (offset), flags); + if (result >= 0 || errno != ENOSYS) + return result; +# endif + /* Trying to emulate the preadv2 syscall flags is troublesome: + + * We can not temporary change the file state of the O_DSYNC and O_SYNC + flags to emulate RWF_{D}SYNC (attempts to change the state of using + fcntl are silently ignored). + + * IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal + semantic not provided by any other flag (O_NONBLOCK for instance). */ + + if (flags != 0) + { + __set_errno (EOPNOTSUPP); + return -1; + } + return preadv (fd, vector, count, offset); +} + +#endif |