1*adf37648SKyle Evans /* SPDX-License-Identifier: GPL-2.0 OR MIT */ 2*adf37648SKyle Evans /* 3*adf37648SKyle Evans * Copyright (C) 2015-2020 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. 4*adf37648SKyle Evans * 5*adf37648SKyle Evans * Specialized constant-time ctype.h reimplementations that aren't locale-specific. 6*adf37648SKyle Evans */ 7*adf37648SKyle Evans 8*adf37648SKyle Evans #ifndef CTYPE_H 9*adf37648SKyle Evans #define CTYPE_H 10*adf37648SKyle Evans 11*adf37648SKyle Evans #include <stdbool.h> 12*adf37648SKyle Evans char_is_space(int c)13*adf37648SKyle Evansstatic inline bool char_is_space(int c) 14*adf37648SKyle Evans { 15*adf37648SKyle Evans unsigned char d = c - 9; 16*adf37648SKyle Evans return (0x80001FU >> (d & 31)) & (1U >> (d >> 5)); 17*adf37648SKyle Evans } 18*adf37648SKyle Evans char_is_digit(int c)19*adf37648SKyle Evansstatic inline bool char_is_digit(int c) 20*adf37648SKyle Evans { 21*adf37648SKyle Evans return (unsigned int)(('0' - 1 - c) & (c - ('9' + 1))) >> (sizeof(c) * 8 - 1); 22*adf37648SKyle Evans } 23*adf37648SKyle Evans char_is_alpha(int c)24*adf37648SKyle Evansstatic inline bool char_is_alpha(int c) 25*adf37648SKyle Evans { 26*adf37648SKyle Evans return (unsigned int)(('a' - 1 - (c | 32)) & ((c | 32) - ('z' + 1))) >> (sizeof(c) * 8 - 1); 27*adf37648SKyle Evans } 28*adf37648SKyle Evans 29*adf37648SKyle Evans #endif 30