mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-26 07:33:47 +00:00
6bbbc38b34
This incorporates: 2017-09-16 manywarnings: port to GCC on 64-bit MS-Windows 2017-09-13 all: Replace many more http URLs by https URLs * build-aux/config.guess, build-aux/config.sub: * build-aux/gitlog-to-changelog, doc/misc/texinfo.tex: * lib/allocator.h, lib/count-leading-zeros.h: * lib/count-trailing-zeros.h, lib/dup2.c, lib/filevercmp.c: * lib/fstatat.c, lib/fsync.c, lib/ftoastr.c, lib/ftoastr.h: * lib/intprops.h, lib/signal.in.h, lib/stdio-impl.h, lib/stdio.in.h: * lib/unistd.in.h, lib/utimens.c, m4/alloca.m4, m4/extern-inline.m4: * m4/fstatat.m4, m4/gnulib-common.m4, m4/manywarnings.m4: * m4/std-gnu11.m4, m4/sys_types_h.m4, m4/vararrays.m4: Copy from Gnulib. * lib/gnulib.mk.in: Regenerate.
632 lines
21 KiB
C
632 lines
21 KiB
C
/* Set file access and modification times.
|
|
|
|
Copyright (C) 2003-2017 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
|
|
Free Software Foundation; either version 3 of the License, or any
|
|
later version.
|
|
|
|
This program 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <https://www.gnu.org/licenses/>. */
|
|
|
|
/* Written by Paul Eggert. */
|
|
|
|
/* derived from a function in touch.c */
|
|
|
|
#include <config.h>
|
|
|
|
#define _GL_UTIMENS_INLINE _GL_EXTERN_INLINE
|
|
#include "utimens.h"
|
|
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <stdbool.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/time.h>
|
|
#include <unistd.h>
|
|
#include <utime.h>
|
|
|
|
#include "stat-time.h"
|
|
#include "timespec.h"
|
|
|
|
/* On native Windows, use SetFileTime; but avoid this when compiling
|
|
GNU Emacs, which arranges for this in some other way and which
|
|
defines WIN32_LEAN_AND_MEAN itself. */
|
|
|
|
#if ((defined _WIN32 || defined __WIN32__) \
|
|
&& ! defined __CYGWIN__ && ! defined EMACS_CONFIGURATION)
|
|
# define USE_SETFILETIME
|
|
# define WIN32_LEAN_AND_MEAN
|
|
# include <windows.h>
|
|
# if GNULIB_MSVC_NOTHROW
|
|
# include "msvc-nothrow.h"
|
|
# else
|
|
# include <io.h>
|
|
# endif
|
|
#endif
|
|
|
|
/* Avoid recursion with rpl_futimens or rpl_utimensat. */
|
|
#undef futimens
|
|
#undef utimensat
|
|
|
|
/* Solaris 9 mistakenly succeeds when given a non-directory with a
|
|
trailing slash. Force the use of rpl_stat for a fix. */
|
|
#ifndef REPLACE_FUNC_STAT_FILE
|
|
# define REPLACE_FUNC_STAT_FILE 0
|
|
#endif
|
|
|
|
#if HAVE_UTIMENSAT || HAVE_FUTIMENS
|
|
/* Cache variables for whether the utimensat syscall works; used to
|
|
avoid calling the syscall if we know it will just fail with ENOSYS,
|
|
and to avoid unnecessary work in massaging timestamps if the
|
|
syscall will work. Multiple variables are needed, to distinguish
|
|
between the following scenarios on Linux:
|
|
utimensat doesn't exist, or is in glibc but kernel 2.6.18 fails with ENOSYS
|
|
kernel 2.6.22 and earlier rejects AT_SYMLINK_NOFOLLOW
|
|
kernel 2.6.25 and earlier reject UTIME_NOW/UTIME_OMIT with non-zero tv_sec
|
|
kernel 2.6.32 used with xfs or ntfs-3g fail to honor UTIME_OMIT
|
|
utimensat completely works
|
|
For each cache variable: 0 = unknown, 1 = yes, -1 = no. */
|
|
static int utimensat_works_really;
|
|
static int lutimensat_works_really;
|
|
#endif /* HAVE_UTIMENSAT || HAVE_FUTIMENS */
|
|
|
|
/* Validate the requested timestamps. Return 0 if the resulting
|
|
timespec can be used for utimensat (after possibly modifying it to
|
|
work around bugs in utimensat). Return a positive value if the
|
|
timespec needs further adjustment based on stat results: 1 if any
|
|
adjustment is needed for utimes, and 2 if any adjustment is needed
|
|
for Linux utimensat. Return -1, with errno set to EINVAL, if
|
|
timespec is out of range. */
|
|
static int
|
|
validate_timespec (struct timespec timespec[2])
|
|
{
|
|
int result = 0;
|
|
int utime_omit_count = 0;
|
|
if ((timespec[0].tv_nsec != UTIME_NOW
|
|
&& timespec[0].tv_nsec != UTIME_OMIT
|
|
&& ! (0 <= timespec[0].tv_nsec
|
|
&& timespec[0].tv_nsec < TIMESPEC_RESOLUTION))
|
|
|| (timespec[1].tv_nsec != UTIME_NOW
|
|
&& timespec[1].tv_nsec != UTIME_OMIT
|
|
&& ! (0 <= timespec[1].tv_nsec
|
|
&& timespec[1].tv_nsec < TIMESPEC_RESOLUTION)))
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
/* Work around Linux kernel 2.6.25 bug, where utimensat fails with
|
|
EINVAL if tv_sec is not 0 when using the flag values of tv_nsec.
|
|
Flag a Linux kernel 2.6.32 bug, where an mtime of UTIME_OMIT
|
|
fails to bump ctime. */
|
|
if (timespec[0].tv_nsec == UTIME_NOW
|
|
|| timespec[0].tv_nsec == UTIME_OMIT)
|
|
{
|
|
timespec[0].tv_sec = 0;
|
|
result = 1;
|
|
if (timespec[0].tv_nsec == UTIME_OMIT)
|
|
utime_omit_count++;
|
|
}
|
|
if (timespec[1].tv_nsec == UTIME_NOW
|
|
|| timespec[1].tv_nsec == UTIME_OMIT)
|
|
{
|
|
timespec[1].tv_sec = 0;
|
|
result = 1;
|
|
if (timespec[1].tv_nsec == UTIME_OMIT)
|
|
utime_omit_count++;
|
|
}
|
|
return result + (utime_omit_count == 1);
|
|
}
|
|
|
|
/* Normalize any UTIME_NOW or UTIME_OMIT values in *TS, using stat
|
|
buffer STATBUF to obtain the current timestamps of the file. If
|
|
both times are UTIME_NOW, set *TS to NULL (as this can avoid some
|
|
permissions issues). If both times are UTIME_OMIT, return true
|
|
(nothing further beyond the prior collection of STATBUF is
|
|
necessary); otherwise return false. */
|
|
static bool
|
|
update_timespec (struct stat const *statbuf, struct timespec *ts[2])
|
|
{
|
|
struct timespec *timespec = *ts;
|
|
if (timespec[0].tv_nsec == UTIME_OMIT
|
|
&& timespec[1].tv_nsec == UTIME_OMIT)
|
|
return true;
|
|
if (timespec[0].tv_nsec == UTIME_NOW
|
|
&& timespec[1].tv_nsec == UTIME_NOW)
|
|
{
|
|
*ts = NULL;
|
|
return false;
|
|
}
|
|
|
|
if (timespec[0].tv_nsec == UTIME_OMIT)
|
|
timespec[0] = get_stat_atime (statbuf);
|
|
else if (timespec[0].tv_nsec == UTIME_NOW)
|
|
gettime (×pec[0]);
|
|
|
|
if (timespec[1].tv_nsec == UTIME_OMIT)
|
|
timespec[1] = get_stat_mtime (statbuf);
|
|
else if (timespec[1].tv_nsec == UTIME_NOW)
|
|
gettime (×pec[1]);
|
|
|
|
return false;
|
|
}
|
|
|
|
/* Set the access and modification timestamps 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 timestamps to the current time.
|
|
Return 0 on success, -1 (setting errno) on failure. */
|
|
|
|
int
|
|
fdutimens (int fd, char const *file, struct timespec const timespec[2])
|
|
{
|
|
struct timespec adjusted_timespec[2];
|
|
struct timespec *ts = timespec ? adjusted_timespec : NULL;
|
|
int adjustment_needed = 0;
|
|
struct stat st;
|
|
|
|
if (ts)
|
|
{
|
|
adjusted_timespec[0] = timespec[0];
|
|
adjusted_timespec[1] = timespec[1];
|
|
adjustment_needed = validate_timespec (ts);
|
|
}
|
|
if (adjustment_needed < 0)
|
|
return -1;
|
|
|
|
/* 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 (fd < 0 && !file)
|
|
{
|
|
errno = EBADF;
|
|
return -1;
|
|
}
|
|
|
|
/* Some Linux-based NFS clients are buggy, and mishandle timestamps
|
|
of files in NFS file systems in some cases. We have no
|
|
configure-time test for this, but please see
|
|
<https://bugs.gentoo.org/show_bug.cgi?id=132673> for references to
|
|
some of the problems with Linux 2.6.16. If this affects you,
|
|
compile with -DHAVE_BUGGY_NFS_TIME_STAMPS; this is reported to
|
|
help in some cases, albeit at a cost in performance. But you
|
|
really should upgrade your kernel to a fixed version, since the
|
|
problem affects many applications. */
|
|
|
|
#if HAVE_BUGGY_NFS_TIME_STAMPS
|
|
if (fd < 0)
|
|
sync ();
|
|
else
|
|
fsync (fd);
|
|
#endif
|
|
|
|
/* POSIX 2008 added two interfaces to set file timestamps with
|
|
nanosecond resolution; newer Linux implements both functions via
|
|
a single syscall. We provide a fallback for ENOSYS (for example,
|
|
compiling against Linux 2.6.25 kernel headers and glibc 2.7, but
|
|
running on Linux 2.6.18 kernel). */
|
|
#if HAVE_UTIMENSAT || HAVE_FUTIMENS
|
|
if (0 <= utimensat_works_really)
|
|
{
|
|
int result;
|
|
# 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.
|
|
|
|
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))
|
|
return -1;
|
|
if (ts[0].tv_nsec == UTIME_OMIT)
|
|
ts[0] = get_stat_atime (&st);
|
|
else if (ts[1].tv_nsec == UTIME_OMIT)
|
|
ts[1] = get_stat_mtime (&st);
|
|
/* Note that st is good, in case utimensat gives ENOSYS. */
|
|
adjustment_needed++;
|
|
}
|
|
# endif
|
|
# if HAVE_UTIMENSAT
|
|
if (fd < 0)
|
|
{
|
|
result = utimensat (AT_FDCWD, file, ts, 0);
|
|
# ifdef __linux__
|
|
/* Work around a kernel bug:
|
|
https://bugzilla.redhat.com/show_bug.cgi?id=442352
|
|
https://bugzilla.redhat.com/show_bug.cgi?id=449910
|
|
It appears that utimensat can mistakenly return 280 rather
|
|
than -1 upon ENOSYS failure.
|
|
FIXME: remove in 2010 or whenever the offending kernels
|
|
are no longer in common use. */
|
|
if (0 < result)
|
|
errno = ENOSYS;
|
|
# endif /* __linux__ */
|
|
if (result == 0 || errno != ENOSYS)
|
|
{
|
|
utimensat_works_really = 1;
|
|
return result;
|
|
}
|
|
}
|
|
# endif /* HAVE_UTIMENSAT */
|
|
# if HAVE_FUTIMENS
|
|
if (0 <= fd)
|
|
{
|
|
result = futimens (fd, ts);
|
|
# ifdef __linux__
|
|
/* Work around the same bug as above. */
|
|
if (0 < result)
|
|
errno = ENOSYS;
|
|
# endif /* __linux__ */
|
|
if (result == 0 || errno != ENOSYS)
|
|
{
|
|
utimensat_works_really = 1;
|
|
return result;
|
|
}
|
|
}
|
|
# endif /* HAVE_FUTIMENS */
|
|
}
|
|
utimensat_works_really = -1;
|
|
lutimensat_works_really = -1;
|
|
#endif /* HAVE_UTIMENSAT || HAVE_FUTIMENS */
|
|
|
|
#ifdef USE_SETFILETIME
|
|
/* On native Windows, use SetFileTime(). See
|
|
<https://msdn.microsoft.com/en-us/library/ms724933.aspx>
|
|
<https://msdn.microsoft.com/en-us/library/ms724284.aspx> */
|
|
if (0 <= fd)
|
|
{
|
|
HANDLE handle;
|
|
FILETIME current_time;
|
|
FILETIME last_access_time;
|
|
FILETIME last_write_time;
|
|
|
|
handle = (HANDLE) _get_osfhandle (fd);
|
|
if (handle == INVALID_HANDLE_VALUE)
|
|
{
|
|
errno = EBADF;
|
|
return -1;
|
|
}
|
|
|
|
if (ts == NULL || ts[0].tv_nsec == UTIME_NOW || ts[1].tv_nsec == UTIME_NOW)
|
|
{
|
|
/* GetSystemTimeAsFileTime
|
|
<https://msdn.microsoft.com/en-us/library/ms724397.aspx>.
|
|
It would be overkill to use
|
|
GetSystemTimePreciseAsFileTime
|
|
<https://msdn.microsoft.com/en-us/library/hh706895.aspx>. */
|
|
GetSystemTimeAsFileTime (¤t_time);
|
|
}
|
|
|
|
if (ts == NULL || ts[0].tv_nsec == UTIME_NOW)
|
|
{
|
|
last_access_time = current_time;
|
|
}
|
|
else if (ts[0].tv_nsec == UTIME_OMIT)
|
|
{
|
|
last_access_time.dwLowDateTime = 0;
|
|
last_access_time.dwHighDateTime = 0;
|
|
}
|
|
else
|
|
{
|
|
ULONGLONG time_since_16010101 =
|
|
(ULONGLONG) ts[0].tv_sec * 10000000 + ts[0].tv_nsec / 100 + 116444736000000000LL;
|
|
last_access_time.dwLowDateTime = (DWORD) time_since_16010101;
|
|
last_access_time.dwHighDateTime = time_since_16010101 >> 32;
|
|
}
|
|
|
|
if (ts == NULL || ts[1].tv_nsec == UTIME_NOW)
|
|
{
|
|
last_write_time = current_time;
|
|
}
|
|
else if (ts[1].tv_nsec == UTIME_OMIT)
|
|
{
|
|
last_write_time.dwLowDateTime = 0;
|
|
last_write_time.dwHighDateTime = 0;
|
|
}
|
|
else
|
|
{
|
|
ULONGLONG time_since_16010101 =
|
|
(ULONGLONG) ts[1].tv_sec * 10000000 + ts[1].tv_nsec / 100 + 116444736000000000LL;
|
|
last_write_time.dwLowDateTime = (DWORD) time_since_16010101;
|
|
last_write_time.dwHighDateTime = time_since_16010101 >> 32;
|
|
}
|
|
|
|
if (SetFileTime (handle, NULL, &last_access_time, &last_write_time))
|
|
return 0;
|
|
else
|
|
{
|
|
DWORD sft_error = GetLastError ();
|
|
#if 0
|
|
fprintf (stderr, "fdutimens SetFileTime error 0x%x\n", (unsigned int) sft_error);
|
|
#endif
|
|
switch (sft_error)
|
|
{
|
|
case ERROR_ACCESS_DENIED: /* fd was opened without O_RDWR */
|
|
errno = EACCES; /* not specified by POSIX */
|
|
break;
|
|
default:
|
|
errno = EINVAL;
|
|
break;
|
|
}
|
|
return -1;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* The platform lacks an interface to set file timestamps with
|
|
nanosecond resolution, so do the best we can, discarding any
|
|
fractional part of the timestamp. */
|
|
|
|
if (adjustment_needed || (REPLACE_FUNC_STAT_FILE && fd < 0))
|
|
{
|
|
if (adjustment_needed != 3
|
|
&& (fd < 0 ? stat (file, &st) : fstat (fd, &st)))
|
|
return -1;
|
|
if (ts && update_timespec (&st, &ts))
|
|
return 0;
|
|
}
|
|
|
|
{
|
|
#if HAVE_FUTIMESAT || HAVE_WORKING_UTIMES
|
|
struct timeval timeval[2];
|
|
struct timeval *t;
|
|
if (ts)
|
|
{
|
|
timeval[0].tv_sec = ts[0].tv_sec;
|
|
timeval[0].tv_usec = ts[0].tv_nsec / 1000;
|
|
timeval[1].tv_sec = ts[1].tv_sec;
|
|
timeval[1].tv_usec = ts[1].tv_nsec / 1000;
|
|
t = timeval;
|
|
}
|
|
else
|
|
t = NULL;
|
|
|
|
if (fd < 0)
|
|
{
|
|
# if HAVE_FUTIMESAT
|
|
return futimesat (AT_FDCWD, file, t);
|
|
# endif
|
|
}
|
|
else
|
|
{
|
|
/* If futimesat or futimes fails here, don't try to speed things
|
|
up by returning right away. glibc can incorrectly fail with
|
|
errno == ENOENT if /proc isn't mounted. Also, Mandrake 10.0
|
|
in high security mode doesn't allow ordinary users to read
|
|
/proc/self, so glibc incorrectly fails with errno == EACCES.
|
|
If errno == EIO, EPERM, or EROFS, it's probably safe to fail
|
|
right away, but these cases are rare enough that they're not
|
|
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) || HAVE_FUTIMES
|
|
# if HAVE_FUTIMESAT && !FUTIMESAT_NULL_BUG
|
|
# undef futimes
|
|
# define futimes(fd, t) futimesat (fd, NULL, t)
|
|
# endif
|
|
if (futimes (fd, t) == 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 */
|
|
|
|
if (!file)
|
|
{
|
|
#if ! ((HAVE_FUTIMESAT && !FUTIMESAT_NULL_BUG) \
|
|
|| (HAVE_WORKING_UTIMES && HAVE_FUTIMES))
|
|
errno = ENOSYS;
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
#ifdef USE_SETFILETIME
|
|
return _gl_utimens_windows (file, ts);
|
|
#elif HAVE_WORKING_UTIMES
|
|
return utimes (file, t);
|
|
#else
|
|
{
|
|
struct utimbuf utimbuf;
|
|
struct utimbuf *ut;
|
|
if (ts)
|
|
{
|
|
utimbuf.actime = ts[0].tv_sec;
|
|
utimbuf.modtime = ts[1].tv_sec;
|
|
ut = &utimbuf;
|
|
}
|
|
else
|
|
ut = NULL;
|
|
|
|
return utime (file, ut);
|
|
}
|
|
#endif /* !HAVE_WORKING_UTIMES */
|
|
}
|
|
}
|
|
|
|
/* Set the access and modification timestamps of FILE to be
|
|
TIMESPEC[0] and TIMESPEC[1], respectively. */
|
|
int
|
|
utimens (char const *file, struct timespec const timespec[2])
|
|
{
|
|
return fdutimens (-1, file, timespec);
|
|
}
|
|
|
|
/* Set the access and modification timestamps of FILE to be
|
|
TIMESPEC[0] and TIMESPEC[1], respectively, without dereferencing
|
|
symlinks. Fail with ENOSYS if the platform does not support
|
|
changing symlink timestamps, but FILE was a symlink. */
|
|
int
|
|
lutimens (char const *file, struct timespec const timespec[2])
|
|
{
|
|
struct timespec adjusted_timespec[2];
|
|
struct timespec *ts = timespec ? adjusted_timespec : NULL;
|
|
int adjustment_needed = 0;
|
|
struct stat st;
|
|
|
|
if (ts)
|
|
{
|
|
adjusted_timespec[0] = timespec[0];
|
|
adjusted_timespec[1] = timespec[1];
|
|
adjustment_needed = validate_timespec (ts);
|
|
}
|
|
if (adjustment_needed < 0)
|
|
return -1;
|
|
|
|
/* The Linux kernel did not support symlink timestamps until
|
|
utimensat, in version 2.6.22, so we don't need to mimic
|
|
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__ || __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.
|
|
|
|
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))
|
|
return -1;
|
|
if (ts[0].tv_nsec == UTIME_OMIT)
|
|
ts[0] = get_stat_atime (&st);
|
|
else if (ts[1].tv_nsec == UTIME_OMIT)
|
|
ts[1] = get_stat_mtime (&st);
|
|
/* Note that st is good, in case utimensat gives ENOSYS. */
|
|
adjustment_needed++;
|
|
}
|
|
# endif
|
|
result = utimensat (AT_FDCWD, file, ts, AT_SYMLINK_NOFOLLOW);
|
|
# ifdef __linux__
|
|
/* Work around a kernel bug:
|
|
https://bugzilla.redhat.com/show_bug.cgi?id=442352
|
|
https://bugzilla.redhat.com/show_bug.cgi?id=449910
|
|
It appears that utimensat can mistakenly return 280 rather
|
|
than -1 upon ENOSYS failure.
|
|
FIXME: remove in 2010 or whenever the offending kernels
|
|
are no longer in common use. */
|
|
if (0 < result)
|
|
errno = ENOSYS;
|
|
# endif
|
|
if (result == 0 || errno != ENOSYS)
|
|
{
|
|
utimensat_works_really = 1;
|
|
lutimensat_works_really = 1;
|
|
return result;
|
|
}
|
|
}
|
|
lutimensat_works_really = -1;
|
|
#endif /* HAVE_UTIMENSAT */
|
|
|
|
/* The platform lacks an interface to set file timestamps with
|
|
nanosecond resolution, so do the best we can, discarding any
|
|
fractional part of the timestamp. */
|
|
|
|
if (adjustment_needed || REPLACE_FUNC_STAT_FILE)
|
|
{
|
|
if (adjustment_needed != 3 && lstat (file, &st))
|
|
return -1;
|
|
if (ts && update_timespec (&st, &ts))
|
|
return 0;
|
|
}
|
|
|
|
/* On Linux, lutimes is a thin wrapper around utimensat, so there is
|
|
no point trying lutimes if utimensat failed with ENOSYS. */
|
|
#if HAVE_LUTIMES && !HAVE_UTIMENSAT
|
|
{
|
|
struct timeval timeval[2];
|
|
struct timeval *t;
|
|
int result;
|
|
if (ts)
|
|
{
|
|
timeval[0].tv_sec = ts[0].tv_sec;
|
|
timeval[0].tv_usec = ts[0].tv_nsec / 1000;
|
|
timeval[1].tv_sec = ts[1].tv_sec;
|
|
timeval[1].tv_usec = ts[1].tv_nsec / 1000;
|
|
t = timeval;
|
|
}
|
|
else
|
|
t = NULL;
|
|
|
|
result = lutimes (file, t);
|
|
if (result == 0 || errno != ENOSYS)
|
|
return result;
|
|
}
|
|
#endif /* HAVE_LUTIMES && !HAVE_UTIMENSAT */
|
|
|
|
/* Out of luck for symlinks, but we still handle regular files. */
|
|
if (!(adjustment_needed || REPLACE_FUNC_STAT_FILE) && lstat (file, &st))
|
|
return -1;
|
|
if (!S_ISLNK (st.st_mode))
|
|
return fdutimens (-1, file, ts);
|
|
errno = ENOSYS;
|
|
return -1;
|
|
}
|