merge from gcc

libiberty/unlink-if-ordinary.c

@@ -0,0 +1,71 @@
+/* unlink-if-ordinary.c - remove link to a file unless it is special
+   Copyright (C) 2004 Free Software Foundation, Inc.
+
+This file is part of the libiberty library.  This library 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 library 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 GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+As a special exception, if you link this library with files
+compiled with a GNU compiler to produce an executable, this does not cause
+the resulting executable to be covered by the GNU General Public License.
+This exception does not however invalidate any other reasons why
+the executable file might be covered by the GNU General Public License. */
+
+/*
+
+@deftypefn Supplemental int unlink_if_ordinary (const char*)
+
+Unlinks the named file, unless it is special (e.g. a device file).
+Returns 0 when the file was unlinked, a negative value (and errno set) when
+there was an error deleting the file, and a positive value if no attempt
+was made to unlink the file because it is special.
+
+@end deftypefn
+
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+
+#include "libiberty.h"
+
+#ifndef S_ISLNK
+#ifdef S_IFLNK
+#define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
+#else
+#define S_ISLNK(m) 0
+#define lstat stat
+#endif
+#endif
+
+int
+unlink_if_ordinary (name)
+  const char *name;
+{
+  struct stat st;
+
+  if (lstat (name, &st) == 0
+      && (S_ISREG (st.st_mode) || S_ISLNK (st.st_mode)))
+    return unlink (name);
+
+  return 1;
+}