glibc/sysdeps/unix/sysv/linux/futimes.c
2005-01-07 04:56:33 +00:00

99 lines
3.0 KiB
C

/* futimes -- change access and modification times of open file. Linux version.
Copyright (C) 2002, 2003, 2005 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <sysdep.h>
#include <string.h>
#include <utime.h>
#include <sys/time.h>
#include <stdio-common/_itoa.h>
#include <fcntl.h>
#include "kernel-features.h"
/* Change the access time of FILE to TVP[0] and
the modification time of FILE to TVP[1], but do not follow symlinks.
The Linux kernel has no futimes() syscall so we use the /proc
filesystem. */
int
__futimes (int fd, const struct timeval tvp[2])
{
static const char selffd[] = "/proc/self/fd/";
char fname[sizeof (selffd) + 3 * sizeof (int)];
fname[sizeof (fname) - 1] = '\0';
char *cp = _itoa_word ((unsigned int) fd, fname + sizeof (fname) - 1, 10, 0);
cp = memcpy (cp - sizeof (selffd) + 1, selffd, sizeof (selffd) - 1);
int result;
#ifdef __NR_utimes
result = INLINE_SYSCALL (utimes, 2, cp, tvp);
# ifndef __ASSUME_UTIMES
if (result == -1 && errno == ENOSYS)
# endif
#endif
{
/* The utimes() syscall does not exist or is not available in the
used kernel. Use utime(). For this we have to convert to the
data format utime() expects. */
#ifndef __ASSUME_UTIMES
struct utimbuf buf;
struct utimbuf *times;
if (tvp != NULL)
{
times = &buf;
buf.actime = tvp[0].tv_sec + (tvp[0].tv_usec + 500000) / 1000000;
buf.modtime = tvp[1].tv_sec + (tvp[1].tv_usec + 500000) / 1000000;
}
else
times = NULL;
result = INLINE_SYSCALL (utime, 2, cp, times);
#endif
}
if (result == -1)
/* Check for errors that result from failing to find /proc.
This means we can't do futimes at all, so return ENOSYS
rather than some confusing error. */
switch (errno)
{
case EACCES:
if (tvp == NULL) /* Could be a path problem or a file problem. */
break;
/*FALLTHROUGH*/
case ELOOP:
case ENAMETOOLONG:
case ENOTDIR:
__set_errno (ENOSYS);
break;
case ENOENT:
/* Validate the file descriptor by letting fcntl set errno to
EBADF if it's bogus. Otherwise it's a /proc issue. */
if (INLINE_SYSCALL (fcntl, 3, fd, F_GETFD, 0) != -1)
__set_errno (ENOSYS);
break;
}
return result;
}
weak_alias (__futimes, futimes)