#include "utimens.h"
+#include <assert.h>
#include <errno.h>
#include <fcntl.h>
+#include <stdbool.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <unistd.h>
+#include "stat-time.h"
+#include "timespec.h"
+
#if HAVE_UTIME_H
# include <utime.h>
#endif
};
#endif
-#ifndef __attribute__
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
-# define __attribute__(x)
-# endif
-#endif
+/* 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 1 if the timespec needs
+ further adjustment based on stat results for utimes or other less
+ powerful interfaces. Return -1, with errno set to EINVAL, if
+ timespec is out of range. */
+static int
+validate_timespec (struct timespec timespec[2])
+{
+ int result = 0;
+ 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))
+ || (timespec[1].tv_nsec != UTIME_NOW
+ && timespec[1].tv_nsec != UTIME_OMIT
+ && (timespec[1].tv_nsec < 0 || 1000000000 <= timespec[1].tv_nsec)))
+ {
+ 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. */
+ if (timespec[0].tv_nsec == UTIME_NOW
+ || timespec[0].tv_nsec == UTIME_OMIT)
+ {
+ timespec[0].tv_sec = 0;
+ result = 1;
+ }
+ if (timespec[1].tv_nsec == UTIME_NOW
+ || timespec[1].tv_nsec == UTIME_OMIT)
+ {
+ timespec[1].tv_sec = 0;
+ result = 1;
+ }
+ return result;
+}
-#ifndef ATTRIBUTE_UNUSED
-# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
-#endif
+/* 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 time stamps of FD (a.k.a. FILE) to be
TIMESPEC[0] and TIMESPEC[1], respectively.
Return 0 on success, -1 (setting errno) on failure. */
int
-gl_futimens (int fd ATTRIBUTE_UNUSED,
- char const *file, struct timespec const timespec[2])
+fdutimens (char const *file, int fd, struct timespec const timespec[2])
{
+ struct timespec adjusted_timespec[2];
+ struct timespec *ts = timespec ? adjusted_timespec : NULL;
+ int adjustment_needed = 0;
+
+ 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 valid. Works around
+ a Linux bug where futimens (AT_FDCWD, NULL) changes "." rather
+ than failing. */
+ if (!file)
+ {
+ if (fd < 0)
+ {
+ errno = EBADF;
+ return -1;
+ }
+ if (dup2 (fd, fd) != fd)
+ return -1;
+ }
+
/* Some Linux-based NFS clients are buggy, and mishandle time stamps
of files in NFS file systems in some cases. We have no
configure-time test for this, but please see
fsync (fd);
#endif
- /* POSIX 200x added two interfaces to set file timestamps with
+ /* POSIX 2008 added two interfaces to set file timestamps with
nanosecond resolution. 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
if (fd < 0)
{
- int result = utimensat (AT_FDCWD, file, timespec, 0);
+ int result = utimensat (AT_FDCWD, file, ts, 0);
# ifdef __linux__
- /* Work around what might be a kernel bug:
+ /* Work around a kernel bug:
http://bugzilla.redhat.com/442352
http://bugzilla.redhat.com/449910
It appears that utimensat can mistakenly return 280 rather
/* 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)
+ {
+ struct stat st;
+ if (fd < 0 ? stat (file, &st) : fstat (fd, &st))
+ return -1;
+ if (update_timespec (&st, &ts))
+ return 0;
+ }
+
{
#if HAVE_FUTIMESAT || HAVE_WORKING_UTIMES
struct timeval timeval[2];
struct timeval const *t;
- if (timespec)
+ if (ts)
{
- timeval[0].tv_sec = timespec[0].tv_sec;
- timeval[0].tv_usec = timespec[0].tv_nsec / 1000;
- timeval[1].tv_sec = timespec[1].tv_sec;
- timeval[1].tv_usec = timespec[1].tv_nsec / 1000;
+ 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
#if ! (HAVE_FUTIMESAT || (HAVE_WORKING_UTIMES && HAVE_FUTIMES))
errno = ENOSYS;
#endif
-
- /* Prefer EBADF to ENOSYS if both error numbers apply. */
- if (errno == ENOSYS)
- {
- int fd2 = dup (fd);
- int dup_errno = errno;
- if (0 <= fd2)
- close (fd2);
- errno = (fd2 < 0 && dup_errno == EBADF ? EBADF : ENOSYS);
- }
-
return -1;
}
#else
{
struct utimbuf utimbuf;
- struct utimbuf const *ut;
- if (timespec)
+ struct utimbuf *ut;
+ if (ts)
{
- utimbuf.actime = timespec[0].tv_sec;
- utimbuf.modtime = timespec[1].tv_sec;
+ utimbuf.actime = ts[0].tv_sec;
+ utimbuf.modtime = ts[1].tv_sec;
ut = &utimbuf;
}
else
}
}
+/* 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
{
return gl_futimens (-1, file, timespec);
}
+
+/* Set the access and modification time stamps of the symlink FILE to
+ be TIMESPEC[0] and TIMESPEC[1], respectively. Fail with ENOSYS if
+ the platform does not support changing symlink timestamps. */
+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;
+
+ 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
+ gl_futimens' worry about buggy NFS clients. But we do have to
+ worry about bogus return values. */
+
+#if HAVE_UTIMENSAT
+ {
+ int result = utimensat (AT_FDCWD, file, ts, AT_SYMLINK_NOFOLLOW);
+# ifdef __linux__
+ /* Work around a kernel bug:
+ http://bugzilla.redhat.com/442352
+ http://bugzilla.redhat.com/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)
+ return result;
+ }
+#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)
+ {
+ struct stat st;
+ if (lstat (file, &st))
+ return -1;
+ if (update_timespec (&st, &ts))
+ return 0;
+ }
+
+#if HAVE_LUTIMES
+ {
+ struct timeval timeval[2];
+ struct timeval const *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;
+
+ return lutimes (file, t);
+ }
+#endif /* HAVE_LUTIMES */
+
+ /* Out of luck. Symlink timestamps can't be changed. We won't
+ bother changing the timestamps if FILE was not a symlink. */
+ errno = ENOSYS;
+ return -1;
+}
projects / gnulib.git / blobdiff