1 /* Linux implementation of pwritev2.
2    Copyright (C) 2017-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <sys/uio.h>
20 #include <sysdep-cancel.h>
21 
22 #ifndef __OFF_T_MATCHES_OFF64_T
23 
24 ssize_t
pwritev2(int fd,const struct iovec * vector,int count,off_t offset,int flags)25 pwritev2 (int fd, const struct iovec *vector, int count, off_t offset,
26 	  int flags)
27 {
28 
29   ssize_t result = SYSCALL_CANCEL (pwritev2, fd, vector, count,
30 				   LO_HI_LONG (offset), flags);
31   if (result >= 0 || errno != ENOSYS)
32     return result;
33 
34   /* Trying to emulate the pwritev2 syscall flags is troublesome:
35 
36      * We can not temporary change the file state of the O_DSYNC and O_SYNC
37        flags to emulate RWF_{D}SYNC (attempts to change the state of using
38        fcntl are silently ignored).
39 
40      * IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal
41        semantic not provided by any other flag (O_NONBLOCK for instance).  */
42 
43   if (flags != 0)
44     {
45       __set_errno (ENOTSUP);
46       return -1;
47     }
48   if (offset == -1)
49     return __writev (fd, vector, count);
50   else
51     return pwritev (fd, vector, count, offset);
52 }
53 
54 #endif
55