forgot to add libbb/get_shell_name.c

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

libbb/get_shell_name.c

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2011, Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+
+//kbuild:lib-y += get_shell_name.o
+
+#include "libbb.h"
+
+const char *get_shell_name(void)
+{
+	struct passwd *pw;
+	char *shell;
+
+	shell = getenv("SHELL");
+	if (shell && shell[0])
+		return shell;
+
+	pw = getpwuid(getuid());
+	if (pw && pw->pw_shell && pw->pw_shell[0])
+		return pw->pw_shell;
+
+	return DEFAULT_SHELL;
+}