1 /* Linux lseek implementation, 32 bits off_t.
2 Copyright (C) 2016-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.
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/>. */
21 #include <sys/types.h>
25 #ifndef __OFF_T_MATCHES_OFF64_T
27 /* Test for overflows of structures where we ask the kernel to fill them
28 in with standard 64-bit syscalls but return them through APIs that
29 only expose the low 32 bits of some fields. */
31 static inline off_t
lseek_overflow (loff_t res
)
33 off_t retval
= (off_t
) res
;
37 __set_errno (EOVERFLOW
);
42 __lseek (int fd
, off_t offset
, int whence
)
45 # define __NR__llseek __NR_llseek
50 int rc
= INLINE_SYSCALL_CALL (_llseek
, fd
,
51 (long) (((uint64_t) (offset
)) >> 32),
52 (long) offset
, &res
, whence
);
53 return rc
?: lseek_overflow (res
);
55 return INLINE_SYSCALL_CALL (lseek
, fd
, offset
, whence
);
58 libc_hidden_def (__lseek
)
59 weak_alias (__lseek
, lseek
)
60 strong_alias (__lseek
, __libc_lseek
)
61 #endif /* __OFF_T_MATCHES_OFF64_T */