1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2019, KAIST 4 */ 5 #include <ctype.h> 6 7 int toupper(int c) 8 { 9 if (c >= 'a' && c <= 'z') 10 return c - 'a' + 'A'; 11 return c; 12 } 13