X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=lib%2Futimens.c;fp=lib%2Futimens.c;h=ffc60b699a68e014ffb1fa12e5596e971ec512af;hb=c7e61475680fa226bd9b8bdd469cd66914e630f5;hp=71bc510d86bb57db59203877a55fdd25d45ab694;hpb=800deb09b422a73c1212233a93839a223ff59678;p=debian%2Fgzip
diff --git a/lib/utimens.c b/lib/utimens.c
index 71bc510..ffc60b6 100644
--- a/lib/utimens.c
+++ b/lib/utimens.c
@@ -1,11 +1,11 @@
/* Set file access and modification times.
- Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software
- Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free
+ Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify it
+ 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 2, or (at your option) any
+ 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,
@@ -14,8 +14,7 @@
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, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program. If not, see . */
/* Written by Paul Eggert. */
@@ -25,11 +24,17 @@
#include "utimens.h"
+#include
#include
#include
+#include
+#include
#include
#include
+#include "stat-time.h"
+#include "timespec.h"
+
#if HAVE_UTIME_H
# include
#endif
@@ -44,26 +49,95 @@ struct utimbuf
};
#endif
-/* Some systems don't have ENOSYS. */
-#ifndef ENOSYS
-# ifdef ENOTSUP
-# define ENOSYS ENOTSUP
-# else
-/* Some systems don't have ENOTSUP either. */
-# define ENOSYS EINVAL
-# endif
-#endif
+/* Avoid recursion with rpl_futimens or rpl_utimensat. */
+#undef futimens
+#undef utimensat
-#ifndef __attribute__
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
-# define __attribute__(x)
-# endif
-#endif
+#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 */
-#ifndef ATTRIBUTE_UNUSED
-# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+/* 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
+/* 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;
+}
+
+/* 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.
FD must be either negative -- in which case it is ignored --
@@ -75,9 +149,35 @@ struct utimbuf
Return 0 on success, -1 (setting errno) on failure. */
int
-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
@@ -95,89 +195,154 @@ futimens (int fd ATTRIBUTE_UNUSED,
fsync (fd);
#endif
- /* There's currently no interface to set file timestamps with
+ /* 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)
+ {
+# 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 */
+ }
+ 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
fractional part of the timestamp. */
-#if HAVE_FUTIMESAT || HAVE_WORKING_UTIMES
- struct timeval timeval[2];
- struct timeval const *t;
- if (timespec)
+
+ if (adjustment_needed || (REPLACE_FUNC_STAT_FILE && fd < 0))
{
- 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;
- t = timeval;
+ struct stat st;
+ if (fd < 0 ? stat (file, &st) : fstat (fd, &st))
+ return -1;
+ if (ts && update_timespec (&st, &ts))
+ return 0;
}
- else
- t = NULL;
+ {
+#if HAVE_FUTIMESAT || HAVE_WORKING_UTIMES
+ 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;
- if (fd < 0)
- {
+ if (fd < 0)
+ {
# if HAVE_FUTIMESAT
- return futimesat (AT_FDCWD, file, t);
+ 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. */
+ }
+ 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
- if (futimesat (fd, NULL, t) == 0)
- return 0;
+ if (futimesat (fd, NULL, t) == 0)
+ return 0;
# elif HAVE_FUTIMES
- if (futimes (fd, t) == 0)
- return 0;
+ if (futimes (fd, t) == 0)
+ return 0;
# endif
- }
-#endif
+ }
+#endif /* HAVE_FUTIMESAT || HAVE_WORKING_UTIMES */
- if (!file)
- {
+ if (!file)
+ {
#if ! (HAVE_FUTIMESAT || (HAVE_WORKING_UTIMES && HAVE_FUTIMES))
- errno = ENOSYS;
+ 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;
- }
+ return -1;
+ }
#if HAVE_WORKING_UTIMES
- return utimes (file, t);
+ return utimes (file, t);
#else
- {
- struct utimbuf utimbuf;
- struct utimbuf const *ut;
- if (timespec)
- {
- utimbuf.actime = timespec[0].tv_sec;
- utimbuf.modtime = timespec[1].tv_sec;
- ut = &utimbuf;
- }
- else
- ut = NULL;
+ {
+ 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);
+ return utime (file, ut);
+ }
+#endif /* !HAVE_WORKING_UTIMES */
}
-#endif
+}
+
+/* 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
@@ -185,5 +350,95 @@ futimens (int fd ATTRIBUTE_UNUSED,
int
utimens (char const *file, struct timespec const timespec[2])
{
- return futimens (-1, file, timespec);
+ return fdutimens (file, -1, timespec);
+}
+
+/* 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)
+ {
+ 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
+ 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;
+# endif
+ 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
+ nanosecond resolution, so do the best we can, discarding any
+ fractional part of the timestamp. */
+
+ if (adjustment_needed || REPLACE_FUNC_STAT_FILE)
+ {
+ if (lstat (file, &st))
+ return -1;
+ if (ts && 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 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 (file, -1, ts);
+ errno = ENOSYS;
+ return -1;
}