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+/* Work around a bug of lstat on some systems
+
+ Copyright (C) 1997-2006, 2008-2016 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 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
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ 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, see <http://www.gnu.org/licenses/>. */
+
+/* written by Jim Meyering */
+
+/* If the user's config.h happens to include <sys/stat.h>, let it include only
+ the system's <sys/stat.h> here, so that orig_lstat doesn't recurse to
+ rpl_lstat. */
+#define __need_system_sys_stat_h
+#include <config.h>
+
+#if !HAVE_LSTAT
+/* On systems that lack symlinks, our replacement <sys/stat.h> already
+ defined lstat as stat, so there is nothing further to do other than
+ avoid an empty file. */
+typedef int dummy;
+#else /* HAVE_LSTAT */
+
+/* Get the original definition of lstat. It might be defined as a macro. */
+# include <sys/types.h>
+# include <sys/stat.h>
+# undef __need_system_sys_stat_h
+
+static int
+orig_lstat (const char *filename, struct stat *buf)
+{
+ return lstat (filename, buf);
+}
+
+/* Specification. */
+/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
+ eliminates this include because of the preliminary #include <sys/stat.h>
+ above. */
+# include "sys/stat.h"
+
+# include <string.h>
+# include <errno.h>
+
+/* 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
+rpl_lstat (const char *file, struct stat *sbuf)
+{
+ size_t len;
+ int lstat_result = orig_lstat (file, sbuf);
+
+ if (lstat_result != 0)
+ return lstat_result;
+
+ /* This replacement file can blindly check against '/' rather than
+ using the ISSLASH macro, because all platforms with '\\' either
+ lack symlinks (mingw) or have working lstat (cygwin) and thus do
+ not compile this file. 0 len should have already been filtered
+ out above, with a failure return of ENOENT. */
+ len = strlen (file);
+ if (file[len - 1] != '/' || S_ISDIR (sbuf->st_mode))
+ return 0;
+
+ /* At this point, a trailing slash is only permitted on
+ symlink-to-dir; but it should have found information on the
+ directory, not the symlink. Call stat() to get info about the
+ link's referent. Our replacement stat guarantees valid results,
+ even if the symlink is not pointing to a directory. */
+ if (!S_ISLNK (sbuf->st_mode))
+ {
+ errno = ENOTDIR;
+ return -1;
+ }
+ return stat (file, sbuf);
+}
+
+#endif /* HAVE_LSTAT */