};
#endif
+/* Avoid recursion with rpl_futimens or rpl_utimensat. */
+#undef futimens
+#undef utimensat
+
+#if HAVE_UTIMENSAT || HAVE_FUTIMENS
+/* Cache variable for whether syscall works; used to avoid calling the
+ syscall if we know it will just fail with ENOSYS. 0 = unknown, 1 =
+ yes, -1 = no. */
+static int utimensat_works_really;
+#endif /* HAVE_UTIMENSAT || HAVE_UTIMENSAT */
+
/* 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
Return 0 on success, -1 (setting errno) on failure. */
int
-gl_futimens (int fd, 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;
#endif
/* 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)
+ 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 = utimensat (AT_FDCWD, file, ts, 0);
-# 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 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;
+# if HAVE_UTIMENSAT
+ if (fd < 0)
+ {
+ int result = utimensat (AT_FDCWD, file, ts, 0);
+# 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 /* __linux__ */
+ if (result == 0 || errno != ENOSYS)
+ {
+ utimensat_works_really = 1;
+ return result;
+ }
+ }
+# endif /* HAVE_UTIMENSAT */
+# if HAVE_FUTIMENS
+ {
+ int result = futimens (fd, timespec);
+# 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 */
}
-#endif
-#if HAVE_FUTIMENS
- {
- int result = futimens (fd, timespec);
-# ifdef __linux__
- /* Work around the same bug as above. */
- if (0 < result)
- errno = ENOSYS;
-# endif
- if (result == 0 || errno != ENOSYS)
- return result;
- }
-#endif
+ utimensat_works_really = -1;
+#endif /* HAVE_UTIMENSAT || HAVE_FUTIMENS */
/* The platform lacks an interface to set file timestamps with
nanosecond resolution, so do the best we can, discarding any
}
}
+/* 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 gl_futimens (-1, file, timespec);
+ return fdutimens (file, -1, 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. */
+/* Set the access and modification time stamps 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)
{
worry about bogus return values. */
#if HAVE_UTIMENSAT
- {
- int result = utimensat (AT_FDCWD, file, ts, AT_SYMLINK_NOFOLLOW);
+ if (0 <= utimensat_works_really)
+ {
+ 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;
+ /* 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;
- }
+ if (result == 0 || errno != ENOSYS)
+ {
+ utimensat_works_really = 1;
+ return result;
+ }
+ }
+ utimensat_works_really = -1;
#endif /* HAVE_UTIMENSAT */
/* The platform lacks an interface to set file timestamps with
if (adjustment_needed)
{
- struct stat st;
if (lstat (file, &st))
return -1;
if (update_timespec (&st, &ts))
}
#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. */
+ /* Out of luck for symlinks, but we still handle regular files. */
+ if (!adjustment_needed && lstat (file, &st))
+ return -1;
+ if (!S_ISLNK (st.st_mode))
+ return fdutimens (file, -1, ts);
errno = ENOSYS;
return -1;
}
projects / gnulib.git / blobdiff