X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Flstat.c;h=3e07270801a9a019c747ca8c83d36136ee0116ca;hb=31d3154399f8c679ba23afb0f6bef03b73d4c741;hp=eb7b22843f14db5a2ed8c8ceef263e84f19f3be6;hpb=0941f53a92efc360e019b76923d0ecd380849939;p=gnulib.git

diff --git a/lib/lstat.c b/lib/lstat.c
index eb7b22843..3e0727080 100644
--- a/lib/lstat.c
+++ b/lib/lstat.c
@@ -1,12 +1,11 @@
-/* Work around the bug in some systems whereby lstat succeeds when
-   given the zero-length file name argument.  The lstat from SunOS4.1.4
-   has this bug.
-   Copyright (C) 1997 Free Software Foundation, Inc.
+/* Work around a bug of lstat on some systems
 
-   This program is free software; you can redistribute it and/or modify
+   Copyright (C) 1997-1999, 2000-2006, 2008 Free Software Foundation, Inc.
+
+   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 later version.
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -14,33 +13,70 @@
    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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* written by Jim Meyering */
 
 #include <config.h>
+
+/* Get the original definition of open.  It might be defined as a macro.  */
+#define __need_system_sys_stat_h
 #include <sys/types.h>
 #include <sys/stat.h>
+#undef __need_system_sys_stat_h
+
+static inline int
+orig_lstat (const char *filename, struct stat *buf)
+{
+  return lstat (filename, buf);
+}
+
+/* Specification.  */
+#include <sys/stat.h>
+
+#include <string.h>
 #include <errno.h>
-#ifndef errno
-extern int errno;
-#endif
 
-/* FIXME: describe.  */
+/* lstat works differently on Linux and Solaris systems.  POSIX (see
+   `pathname resolution' in the glossary) requires that programs like
+   `ls' take into consideration the fact that FILE has a trailing slash
+   when FILE is a symbolic link.  On Linux and Solaris 10 systems, the
+   lstat function already has the desired semantics (in treating
+   `lstat ("symlink/", sbuf)' just like `lstat ("symlink/.", sbuf)',
+   but on Solaris 9 and earlier it does not.
+
+   If FILE has a trailing slash and specifies a symbolic link,
+   then use stat() to get more info on the referent of FILE.
+   If the referent is a non-directory, then set errno to ENOTDIR
+   and return -1.  Otherwise, return stat's result.  */
 
 int
-lstat (file, sbuf)
-     const char *file;
-     struct stat *sbuf;
+rpl_lstat (const char *file, struct stat *sbuf)
 {
-  if (file && *file == 0)
-    {
-      errno = EINVAL;
-      return -1;
-    }
+  size_t len;
+  int lstat_result = orig_lstat (file, sbuf);
+
+  if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode))
+    return lstat_result;
+
+  len = strlen (file);
+  if (len == 0 || file[len - 1] != '/')
+    return 0;
+
+  /* FILE refers to a symbolic link and the name ends with a slash.
+     Call stat() to get info about the link's referent.  */
+
+  /* If stat fails, then we do the same.  */
+  if (stat (file, sbuf) != 0)
+    return -1;
 
-#undef lstat
+  /* If FILE references a directory, return 0.  */
+  if (S_ISDIR (sbuf->st_mode))
+    return 0;
 
-  return lstat (file, sbuf);
+  /* Here, we know stat succeeded and FILE references a non-directory.
+     But it was specified via a name including a trailing slash.
+     Fail with errno set to ENOTDIR to indicate the contradiction.  */
+  errno = ENOTDIR;
+  return -1;
 }