/* Set file access and modification times.
- Copyright (C) 2003-2010 Free Software Foundation, Inc.
+ Copyright (C) 2003-2014 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
#include <config.h>
+#define _GL_UTIMENS_INLINE _GL_EXTERN_INLINE
#include "utimens.h"
#include <assert.h>
assert (timespec);
if ((timespec[0].tv_nsec != UTIME_NOW
&& timespec[0].tv_nsec != UTIME_OMIT
- && (timespec[0].tv_nsec < 0 || 1000000000 <= timespec[0].tv_nsec))
+ && ! (0 <= timespec[0].tv_nsec
+ && timespec[0].tv_nsec < TIMESPEC_RESOLUTION))
|| (timespec[1].tv_nsec != UTIME_NOW
&& timespec[1].tv_nsec != UTIME_OMIT
- && (timespec[1].tv_nsec < 0 || 1000000000 <= timespec[1].tv_nsec)))
+ && ! (0 <= timespec[1].tv_nsec
+ && timespec[1].tv_nsec < TIMESPEC_RESOLUTION)))
{
errno = EINVAL;
return -1;
Return 0 on success, -1 (setting errno) on failure. */
int
-fdutimens (char const *file, int fd, struct timespec const timespec[2])
+fdutimens (int fd, char const *file, struct timespec const timespec[2])
{
struct timespec adjusted_timespec[2];
struct timespec *ts = timespec ? adjusted_timespec : NULL;
if (adjustment_needed < 0)
return -1;
- /* Require that at least one of FD or FILE are valid. Works around
+ /* Require that at least one of FD or FILE are potentially valid, to avoid
a Linux bug where futimens (AT_FDCWD, NULL) changes "." rather
than failing. */
- if (!file)
+ if (fd < 0 && !file)
{
- if (fd < 0)
- {
- errno = EBADF;
- return -1;
- }
- if (dup2 (fd, fd) != fd)
- return -1;
+ errno = EBADF;
+ return -1;
}
/* Some Linux-based NFS clients are buggy, and mishandle time stamps
if (0 <= utimensat_works_really)
{
int result;
-# if __linux__
+# if __linux__ || __sun
/* As recently as Linux kernel 2.6.32 (Dec 2009), several file
systems (xfs, ntfs-3g) have bugs with a single UTIME_OMIT,
but work if both times are either explicitly specified or
UTIME_NOW. Work around it with a preparatory [f]stat prior
to calling futimens/utimensat; fortunately, there is not much
timing impact due to the extra syscall even on file systems
- where UTIME_OMIT would have worked. FIXME: Simplify this in
- 2012, when file system bugs are no longer common. */
+ where UTIME_OMIT would have worked.
+
+ The same bug occurs in Solaris 11.1 (Apr 2013).
+
+ FIXME: Simplify this for Linux in 2016 and for Solaris in
+ 2024, when file system bugs are no longer common. */
if (adjustment_needed == 2)
{
if (fd < 0 ? stat (file, &st) : fstat (fd, &st))
/* Note that st is good, in case utimensat gives ENOSYS. */
adjustment_needed++;
}
-# endif /* __linux__ */
+# endif
# if HAVE_UTIMENSAT
if (fd < 0)
{
worth optimizing, and who knows what other messed-up systems
are out there? So play it safe and fall back on the code
below. */
-# if HAVE_FUTIMESAT && !FUTIMESAT_NULL_BUG
- if (futimesat (fd, NULL, t) == 0)
- return 0;
-# elif HAVE_FUTIMES
+
+# if (HAVE_FUTIMESAT && !FUTIMESAT_NULL_BUG) || HAVE_FUTIMES
+# if HAVE_FUTIMESAT && !FUTIMESAT_NULL_BUG
+# undef futimes
+# define futimes(fd, t) futimesat (fd, NULL, t)
+# endif
if (futimes (fd, t) == 0)
- return 0;
+ {
+# if __linux__ && __GLIBC__
+ /* Work around a longstanding glibc bug, still present as
+ of 2010-12-27. On older Linux kernels that lack both
+ utimensat and utimes, glibc's futimes rounds instead of
+ truncating when falling back on utime. The same bug
+ occurs in futimesat with a null 2nd arg. */
+ if (t)
+ {
+ bool abig = 500000 <= t[0].tv_usec;
+ bool mbig = 500000 <= t[1].tv_usec;
+ if ((abig | mbig) && fstat (fd, &st) == 0)
+ {
+ /* If these two subtractions overflow, they'll
+ track the overflows inside the buggy glibc. */
+ time_t adiff = st.st_atime - t[0].tv_sec;
+ time_t mdiff = st.st_mtime - t[1].tv_sec;
+
+ struct timeval *tt = NULL;
+ struct timeval truncated_timeval[2];
+ truncated_timeval[0] = t[0];
+ truncated_timeval[1] = t[1];
+ if (abig && adiff == 1 && get_stat_atime_ns (&st) == 0)
+ {
+ tt = truncated_timeval;
+ tt[0].tv_usec = 0;
+ }
+ if (mbig && mdiff == 1 && get_stat_mtime_ns (&st) == 0)
+ {
+ tt = truncated_timeval;
+ tt[1].tv_usec = 0;
+ }
+ if (tt)
+ futimes (fd, tt);
+ }
+ }
+# endif
+
+ return 0;
+ }
# endif
}
#endif /* HAVE_FUTIMESAT || HAVE_WORKING_UTIMES */
}
}
-/* Set the access and modification time stamps of FD (a.k.a. FILE) to be
- TIMESPEC[0] and TIMESPEC[1], respectively.
- FD must be either negative -- in which case it is ignored --
- or a file descriptor that is open on FILE.
- If FD is nonnegative, then FILE can be NULL, which means
- use just futimes (or equivalent) instead of utimes (or equivalent),
- and fail if on an old system without futimes (or equivalent).
- If TIMESPEC is null, set the time stamps to the current time.
- Return 0 on success, -1 (setting errno) on failure. */
-
-int
-gl_futimens (int fd, char const *file, struct timespec const timespec[2])
-{
- return fdutimens (file, fd, timespec);
-}
-
/* Set the access and modification time stamps of FILE to be
TIMESPEC[0] and TIMESPEC[1], respectively. */
int
utimens (char const *file, struct timespec const timespec[2])
{
- return fdutimens (file, -1, timespec);
+ return fdutimens (-1, file, timespec);
}
/* Set the access and modification time stamps of FILE to be
/* The Linux kernel did not support symlink timestamps until
utimensat, in version 2.6.22, so we don't need to mimic
- gl_futimens' worry about buggy NFS clients. But we do have to
+ fdutimens' worry about buggy NFS clients. But we do have to
worry about bogus return values. */
#if HAVE_UTIMENSAT
if (0 <= lutimensat_works_really)
{
int result;
-# if __linux__
+# if __linux__ || __sun
/* As recently as Linux kernel 2.6.32 (Dec 2009), several file
systems (xfs, ntfs-3g) have bugs with a single UTIME_OMIT,
but work if both times are either explicitly specified or
UTIME_NOW. Work around it with a preparatory lstat prior to
calling utimensat; fortunately, there is not much timing
impact due to the extra syscall even on file systems where
- UTIME_OMIT would have worked. FIXME: Simplify this in 2012,
- when file system bugs are no longer common. */
+ UTIME_OMIT would have worked.
+
+ The same bug occurs in Solaris 11.1 (Apr 2013).
+
+ FIXME: Simplify this for Linux in 2016 and for Solaris in
+ 2024, when file system bugs are no longer common. */
if (adjustment_needed == 2)
{
if (lstat (file, &st))
/* Note that st is good, in case utimensat gives ENOSYS. */
adjustment_needed++;
}
-# endif /* __linux__ */
+# endif
result = utimensat (AT_FDCWD, file, ts, AT_SYMLINK_NOFOLLOW);
# ifdef __linux__
/* Work around a kernel bug:
if (!(adjustment_needed || REPLACE_FUNC_STAT_FILE) && lstat (file, &st))
return -1;
if (!S_ISLNK (st.st_mode))
- return fdutimens (file, -1, ts);
+ return fdutimens (-1, file, ts);
errno = ENOSYS;
return -1;
}
projects / gnulib.git / blobdiff