AP_Scripting: added isdirectory()

libraries/AP_Scripting/lua_bindings.cpp

@@ -720,6 +720,25 @@ int lua_dirlist(lua_State *L) {
     return 1;  /* table is already on top */
 }
 
+/*
+  return true if path is a directory
+ */
+int lua_isdirectory(lua_State *L) {
+    binding_argcheck(L, 1);
+
+    const char *path = luaL_checkstring(L, 1);
+    
+    struct stat st;
+    if (AP::FS().stat(path, &st) != 0) {
+        lua_pushnil(L);  /* return nil and ... */
+        lua_pushstring(L, strerror(errno));  /* error message */
+        return 2;
+    }
+    bool ret = (st.st_mode & S_IFMT) == S_IFDIR;
+    lua_pushboolean(L, ret);
+    return 1;
+}
+
 /*
   remove a file
  */