glibc/sysdeps/unix/sysv/linux/fexecve.c
Paul Eggert 2b778ceb40 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
2021-01-02 12:17:34 -08:00

72 lines
2.1 KiB
C

/* Copyright (C) 1994-2021 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
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sysdep.h>
#include <sys/syscall.h>
#include <kernel-features.h>
/* Execute the file FD refers to, overlaying the running program image.
ARGV and ENVP are passed to the new program, as for `execve'. */
int
fexecve (int fd, char *const argv[], char *const envp[])
{
if (fd < 0 || argv == NULL || envp == NULL)
{
__set_errno (EINVAL);
return -1;
}
#ifdef __NR_execveat
/* Avoid implicit array coercion in syscall macros. */
INLINE_SYSCALL (execveat, 5, fd, "", &argv[0], &envp[0], AT_EMPTY_PATH);
# ifndef __ASSUME_EXECVEAT
if (errno != ENOSYS)
return -1;
# endif
#endif
#ifndef __ASSUME_EXECVEAT
/* We use the /proc filesystem to get the information. If it is not
mounted we fail. */
char buf[sizeof "/proc/self/fd/" + sizeof (int) * 3];
__snprintf (buf, sizeof (buf), "/proc/self/fd/%d", fd);
/* We do not need the return value. */
__execve (buf, argv, envp);
int save = errno;
/* We come here only if the 'execve' call fails. Determine whether
/proc is mounted. If not we return ENOSYS. */
struct stat64 st;
if (__stat64 ("/proc/self/fd", &st) != 0 && errno == ENOENT)
save = ENOSYS;
__set_errno (save);
#endif
return -1;
}