'trap' portability trapped me...

[gnulib.git] / lib / utimens.c

diff --git a/lib/utimens.c b/lib/utimens.c
index b60ec87..8d8bef4 100644 (file)
--- a/lib/utimens.c
+++ b/lib/utimens.c
@@ -26,6 +26,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <unistd.h>
 
 #if HAVE_UTIME_H
 # include <utime.h>
@@ -98,26 +99,37 @@ futimens (int fd ATTRIBUTE_UNUSED,
       if (futimes (fd, t) == 0)
        return 0;
 
-      /* On GNU/Linux without the futimes syscall and without /proc
-        mounted, glibc futimes fails with errno == ENOENT.  Fall back
-        on utimes if we get a weird error number like that.  */
-      switch (errno)
-       {
-       case EACCES:
-       case EIO:
-       case EPERM:
-       case EROFS:
-         return -1;
-       }
+      /* Don't worry about trying to speed things up by returning right
+        away here.  glibc futimes 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 futimes incorrectly fails with errno == EACCES.  If futimes
+        fails with 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.  */
     }
 # endif
 #endif
 
-#if ! HAVE_FUTIMES_AT
+#if ! HAVE_FUTIMESAT
 
   if (!file)
     {
+# if ! (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;
     }