string: add GNU basename(3)

* libc/include/libgen.h (_BASENAME_DEFINED): Define.
* libc/include/string.h (basename): Declare.
* libc/string/Makefile.am (ELIX_4_SOURCES): Add gnu_basename.c.
* libc/string/Makefile.in: Regenerate.
* libc/string/gnu_basename.c: New file.

1 files changed, 26 insertions, 0 deletions

diff --git a/newlib/libc/string/gnu_basename.c b/newlib/libc/string/gnu_basename.c
new file mode 100644
index 000000000..46b92d0fd
--- /dev/null
+++ b/newlib/libc/string/gnu_basename.c
@@ -0,0 +1,26 @@
+#ifndef _NO_BASENAME
+/* Copyright 2015 Red Hat, Inc.
+ * Permission to use, copy, modify, and distribute this software
+ * is freely granted, provided that this notice is preserved.
+ */
+
+/* The differences with the POSIX version (unix/basename.c):
+ * - declared in <string.h> (instead of <libgen.h>);
+ * - the argument is never modified, and therefore is marked const;
+ * - the empty string is returned if path is an empty string, "/", or ends
+ *   with a trailing slash.
+ */
+
+#include <string.h>
+
+char *
+_DEFUN (__gnu_basename, (path),
+	const char *path)
+{
+  char *p;
+  if ((p = strrchr (path, '/')))
+    return p + 1;
+  return path;
+}
+
+#endif /* !_NO_BASENAME  */