1//===-- Collection of utils for implementing ctype functions-------*-C++-*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLVM_LIBC_SRC___SUPPORT_CTYPE_UTILS_H
10#define LLVM_LIBC_SRC___SUPPORT_CTYPE_UTILS_H
11
12#include "src/__support/macros/attributes.h"
13
14namespace LIBC_NAMESPACE {
15namespace internal {
16
17// ------------------------------------------------------
18// Rationale: Since these classification functions are
19// called in other functions, we will avoid the overhead
20// of a function call by inlining them.
21// ------------------------------------------------------
22
23LIBC_INLINE static constexpr bool isalpha(unsigned ch) {
24 return (ch | 32) - 'a' < 26;
25}
26
27LIBC_INLINE static constexpr bool isdigit(unsigned ch) {
28 return (ch - '0') < 10;
29}
30
31LIBC_INLINE static constexpr bool isalnum(unsigned ch) {
32 return isalpha(ch) || isdigit(ch);
33}
34
35LIBC_INLINE static constexpr bool isgraph(unsigned ch) {
36 return 0x20 < ch && ch < 0x7f;
37}
38
39LIBC_INLINE static constexpr bool islower(unsigned ch) {
40 return (ch - 'a') < 26;
41}
42
43LIBC_INLINE static constexpr bool isupper(unsigned ch) {
44 return (ch - 'A') < 26;
45}
46
47LIBC_INLINE static constexpr bool isspace(unsigned ch) {
48 return ch == ' ' || (ch - '\t') < 5;
49}
50
51LIBC_INLINE static constexpr int tolower(int ch) {
52 if (isupper(ch))
53 return ch + ('a' - 'A');
54 return ch;
55}
56
57} // namespace internal
58} // namespace LIBC_NAMESPACE
59
60#endif // LLVM_LIBC_SRC___SUPPORT_CTYPE_UTILS_H
61

source code of libc/src/__support/ctype_utils.h