maint: minor cleanups

[gnulib.git] / lib / utimens.c

diff --git a/lib/utimens.c b/lib/utimens.c
index 1489df0..10d2c82 100644 (file)
--- a/lib/utimens.c
+++ b/lib/utimens.c
@@ -1,10 +1,11 @@
 /* Set file access and modification times.
 
 /* Set file access and modification times.
 

-   Copyright (C) 2003, 2004, 2005, 2006 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
    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,
    later version.
 
    This program is distributed in the hope that it will be useful,


@@ -13,21 +14,20 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    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 <http://www.gnu.org/licenses/>.  */

 
 /* Written by Paul Eggert.  */
 
 /* derived from a function in touch.c */
 
 
 /* Written by Paul Eggert.  */
 
 /* derived from a function in touch.c */
 

-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>

 
 #include "utimens.h"
 
 #include <errno.h>
 #include <fcntl.h>
 
 #include "utimens.h"
 
 #include <errno.h>
 #include <fcntl.h>

+#include <sys/stat.h>
+#include <sys/time.h>

 #include <unistd.h>
 
 #if HAVE_UTIME_H
 #include <unistd.h>
 
 #if HAVE_UTIME_H


@@ -44,26 +44,6 @@ struct utimbuf
 };
 #endif
 
 };
 #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
-
-#ifndef __attribute__
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
-#  define __attribute__(x)
-# endif
-#endif
-
-#ifndef ATTRIBUTE_UNUSED
-# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
-#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 --
 /* 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 --


@@ -75,92 +55,147 @@ struct utimbuf
    Return 0 on success, -1 (setting errno) on failure.  */
 
 int
    Return 0 on success, -1 (setting errno) on failure.  */
 
 int

-futimens (int fd ATTRIBUTE_UNUSED,
-         char const *file, struct timespec const timespec[2])
+gl_futimens (int fd _UNUSED_PARAMETER_,
+             char const *file, struct timespec const timespec[2])

 {
 {

-  /* There's currently no 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)
-    {
-      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;
-    }
+  /* 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
+     <http://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
   else

-    t = NULL;
-
+    fsync (fd);
+#endif

 
 

+  /* POSIX 200x 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)
     {
   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
-      if (futimesat (fd, NULL, t) == 0)
-       return 0;
-# elif HAVE_FUTIMES
-      if (futimes (fd, t) == 0)
-       return 0;
+      int result = utimensat (AT_FDCWD, file, timespec, 0);
+# ifdef __linux__
+      /* Work around what might be 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
 # endif

+
+      if (result == 0 || errno != ENOSYS)
+        return result;

     }
 #endif
     }
 #endif

-
-  if (!file)
-    {
-#if ! (HAVE_FUTIMESAT || (HAVE_WORKING_UTIMES && HAVE_FUTIMES))
+#if HAVE_FUTIMENS
+  {
+    int result = futimens (fd, timespec);
+# ifdef __linux__
+    /* Work around the same bug as above.  */
+    if (0 < result)

       errno = ENOSYS;
       errno = ENOSYS;

+# endif
+    if (result == 0 || errno != ENOSYS)
+      return result;
+  }

 #endif
 
 #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;
-    }
-
-#if HAVE_WORKING_UTIMES
-  return utimes (file, t);
-#else
+  /* 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.  */

   {
   {

-    struct utimbuf utimbuf;
-    struct utimbuf const *ut;
+#if HAVE_FUTIMESAT || HAVE_WORKING_UTIMES
+    struct timeval timeval[2];
+    struct timeval const *t;

     if (timespec)
       {
     if (timespec)
       {

-       utimbuf.actime = timespec[0].tv_sec;
-       utimbuf.modtime = timespec[1].tv_sec;
-       ut = &utimbuf;
+        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;

       }
     else
       }
     else

-      ut = NULL;
+      t = NULL;

 
 

-    return utime (file, ut);
-  }
+    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
+        if (futimesat (fd, NULL, t) == 0)
+          return 0;
+# elif HAVE_FUTIMES
+        if (futimes (fd, t) == 0)
+          return 0;
+# endif
+      }
+#endif /* HAVE_FUTIMESAT || HAVE_WORKING_UTIMES */
+
+    if (!file)
+      {
+#if ! (HAVE_FUTIMESAT || (HAVE_WORKING_UTIMES && HAVE_FUTIMES))
+        errno = ENOSYS;

 #endif
 #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;
+      }
+
+#if HAVE_WORKING_UTIMES
+    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;
+
+      return utime (file, ut);
+    }
+#endif /* !HAVE_WORKING_UTIMES */
+  }

 }
 
 /* Set the access and modification time stamps of FILE to be
 }
 
 /* Set the access and modification time stamps of FILE to be


@@ -168,5 +203,5 @@ futimens (int fd ATTRIBUTE_UNUSED,
 int
 utimens (char const *file, struct timespec const timespec[2])
 {
 int
 utimens (char const *file, struct timespec const timespec[2])
 {

-  return futimens (-1, file, timespec);
+  return gl_futimens (-1, file, timespec);

 }
 }