From: Jim Meyering <jim@meyering.net>
Date: Wed, 4 Dec 2002 10:11:15 +0000 (+0000)
Subject: * stat.c: New file.  Contents mostly from xstat.in.
X-Git-Tag: cvs-readonly~5116
X-Git-Url: http://erislabs.net/gitweb/?a=commitdiff_plain;h=6cb5549df8b0760c80962662441d7228a8eca96b;p=gnulib.git

* stat.c: New file.  Contents mostly from xstat.in.
Rework so that it may serve to define rpl_lstat, too.
---

diff --git a/lib/stat.c b/lib/stat.c
new file mode 100644
index 000000000..f3f373b95
--- /dev/null
+++ b/lib/stat.c
@@ -0,0 +1,128 @@
+/* Work around the bug in some systems whereby stat/lstat succeeds when
+   given the zero-length file name argument.  The stat/lstat from SunOS4.1.4
+   has this bug.
+   Copyright (C) 1997-2002 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.
+
+   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, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+/* written by Jim Meyering */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#ifndef errno
+extern int errno;
+#endif
+#ifdef LSTAT
+# include <string.h>
+
+# if HAVE_STDLIB_H
+#  include <stdlib.h>
+# endif
+
+# ifdef STAT_MACROS_BROKEN
+#  undef S_ISLNK
+# endif
+
+# ifndef S_ISLNK
+#  ifdef S_IFLNK
+#   define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
+#  else
+#   define S_ISLNK(m) 0
+#  endif
+# endif
+
+# ifndef HAVE_DECL_FREE
+"this configure-time declaration test was not run"
+# endif
+# if !HAVE_DECL_FREE
+void free ();
+# endif
+
+char *xmalloc ();
+
+/* 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 systems, the lstat function already
+   has the desired semantics (in treating `lstat("symlink/",sbuf)' just like
+   `lstat("symlink/.",sbuf)', but on Solaris it does not.
+
+   If FILE has a trailing slash and specifies a symbolic link,
+   then append a `.' to FILE and call lstat a second time.  */
+
+static int
+slash_aware_lstat (const char *file, struct stat *sbuf)
+{
+  size_t len;
+  char *new_file;
+
+  int lstat_result = lstat (file, sbuf);
+
+  if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode))
+    return lstat_result;
+
+  len = strlen (file);
+  if (file[len - 1] != '/')
+    return lstat_result;
+
+  /* FILE refers to a symbolic link and the name ends with a slash.
+     Append a `.' to FILE and repeat the lstat call.  */
+
+  /* Add one for the `.' we'll append, and one more for the trailing NUL.  */
+  new_file = xmalloc (len + 1 + 1);
+  memcpy (new_file, file, len);
+  new_file[len] = '.';
+  new_file[len + 1] = 0;
+
+  lstat_result = lstat (new_file, sbuf);
+  free (new_file);
+
+  return lstat_result;
+}
+#endif /* LSTAT */
+
+/* This is a wrapper for stat/lstat.
+   If FILE is the empty string, fail with errno == ENOENT.
+   Otherwise, return the result of calling the real stat/lstat.
+
+   This works around the bug in some systems whereby stat/lstat succeeds when
+   given the zero-length file name argument.  The stat/lstat from SunOS4.1.4
+   has this bug.  */
+
+/* This function also provides a version of lstat with consistent semantics
+   when FILE specifies a symbolic link and has a trailing slash.  */
+
+#ifdef LSTAT
+# define rpl_xstat rpl_lstat
+# define xstat_return_val(F, S) slash_aware_lstat (F, S)
+#else
+# define rpl_xstat rpl_stat
+# define xstat_return_val(F, S) stat (F, S)
+#endif
+
+int
+rpl_xstat (const char *file, struct stat *sbuf)
+{
+  if (file && *file == 0)
+    {
+      errno = ENOENT;
+      return -1;
+    }
+
+  return xstat_return_val (file, sbuf);
+}