1//===--- clang/Basic/CharInfo.h - Classifying ASCII Characters --*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef LLVM_CLANG_BASIC_CHARINFO_H
11#define LLVM_CLANG_BASIC_CHARINFO_H
12
13#include "clang/Basic/LLVM.h"
14#include "llvm/ADT/StringRef.h"
15#include "llvm/Support/Compiler.h"
16#include "llvm/Support/DataTypes.h"
17
18namespace clang {
19namespace charinfo {
20 extern const uint16_t InfoTable[256];
21
22 enum {
23 CHAR_HORZ_WS = 0x0001, // '\t', '\f', '\v'. Note, no '\0'
24 CHAR_VERT_WS = 0x0002, // '\r', '\n'
25 CHAR_SPACE = 0x0004, // ' '
26 CHAR_DIGIT = 0x0008, // 0-9
27 CHAR_XLETTER = 0x0010, // a-f,A-F
28 CHAR_UPPER = 0x0020, // A-Z
29 CHAR_LOWER = 0x0040, // a-z
30 CHAR_UNDER = 0x0080, // _
31 CHAR_PERIOD = 0x0100, // .
32 CHAR_RAWDEL = 0x0200, // {}[]#<>%:;?*+-/^&|~!=,"'
33 CHAR_PUNCT = 0x0400 // `$@()
34 };
35
36 enum {
37 CHAR_XUPPER = CHAR_XLETTER | CHAR_UPPER,
38 CHAR_XLOWER = CHAR_XLETTER | CHAR_LOWER
39 };
40} // end namespace charinfo
41
42/// Returns true if this is an ASCII character.
43LLVM_READNONE inline bool isASCII(char c) {
44 return static_cast<unsigned char>(c) <= 127;
45}
46
47/// Returns true if this is a valid first character of a C identifier,
48/// which is [a-zA-Z_].
49LLVM_READONLY inline bool isIdentifierHead(unsigned char c,
50 bool AllowDollar = false) {
51 using namespace charinfo;
52 if (InfoTable[c] & (CHAR_UPPER|CHAR_LOWER|CHAR_UNDER))
53 return true;
54 return AllowDollar && c == '$';
55}
56
57/// Returns true if this is a body character of a C identifier,
58/// which is [a-zA-Z0-9_].
59LLVM_READONLY inline bool isIdentifierBody(unsigned char c,
60 bool AllowDollar = false) {
61 using namespace charinfo;
62 if (InfoTable[c] & (CHAR_UPPER|CHAR_LOWER|CHAR_DIGIT|CHAR_UNDER))
63 return true;
64 return AllowDollar && c == '$';
65}
66
67/// Returns true if this character is horizontal ASCII whitespace:
68/// ' ', '\\t', '\\f', '\\v'.
69///
70/// Note that this returns false for '\\0'.
71LLVM_READONLY inline bool isHorizontalWhitespace(unsigned char c) {
72 using namespace charinfo;
73 return (InfoTable[c] & (CHAR_HORZ_WS|CHAR_SPACE)) != 0;
74}
75
76/// Returns true if this character is vertical ASCII whitespace: '\\n', '\\r'.
77///
78/// Note that this returns false for '\\0'.
79LLVM_READONLY inline bool isVerticalWhitespace(unsigned char c) {
80 using namespace charinfo;
81 return (InfoTable[c] & CHAR_VERT_WS) != 0;
82}
83
84/// Return true if this character is horizontal or vertical ASCII whitespace:
85/// ' ', '\\t', '\\f', '\\v', '\\n', '\\r'.
86///
87/// Note that this returns false for '\\0'.
88LLVM_READONLY inline bool isWhitespace(unsigned char c) {
89 using namespace charinfo;
90 return (InfoTable[c] & (CHAR_HORZ_WS|CHAR_VERT_WS|CHAR_SPACE)) != 0;
91}
92
93/// Return true if this character is an ASCII digit: [0-9]
94LLVM_READONLY inline bool isDigit(unsigned char c) {
95 using namespace charinfo;
96 return (InfoTable[c] & CHAR_DIGIT) != 0;
97}
98
99/// Return true if this character is a lowercase ASCII letter: [a-z]
100LLVM_READONLY inline bool isLowercase(unsigned char c) {
101 using namespace charinfo;
102 return (InfoTable[c] & CHAR_LOWER) != 0;
103}
104
105/// Return true if this character is an uppercase ASCII letter: [A-Z]
106LLVM_READONLY inline bool isUppercase(unsigned char c) {
107 using namespace charinfo;
108 return (InfoTable[c] & CHAR_UPPER) != 0;
109}
110
111/// Return true if this character is an ASCII letter: [a-zA-Z]
112LLVM_READONLY inline bool isLetter(unsigned char c) {
113 using namespace charinfo;
114 return (InfoTable[c] & (CHAR_UPPER|CHAR_LOWER)) != 0;
115}
116
117/// Return true if this character is an ASCII letter or digit: [a-zA-Z0-9]
118LLVM_READONLY inline bool isAlphanumeric(unsigned char c) {
119 using namespace charinfo;
120 return (InfoTable[c] & (CHAR_DIGIT|CHAR_UPPER|CHAR_LOWER)) != 0;
121}
122
123/// Return true if this character is an ASCII hex digit: [0-9a-fA-F]
124LLVM_READONLY inline bool isHexDigit(unsigned char c) {
125 using namespace charinfo;
126 return (InfoTable[c] & (CHAR_DIGIT|CHAR_XLETTER)) != 0;
127}
128
129/// Return true if this character is an ASCII punctuation character.
130///
131/// Note that '_' is both a punctuation character and an identifier character!
132LLVM_READONLY inline bool isPunctuation(unsigned char c) {
133 using namespace charinfo;
134 return (InfoTable[c] & (CHAR_UNDER|CHAR_PERIOD|CHAR_RAWDEL|CHAR_PUNCT)) != 0;
135}
136
137/// Return true if this character is an ASCII printable character; that is, a
138/// character that should take exactly one column to print in a fixed-width
139/// terminal.
140LLVM_READONLY inline bool isPrintable(unsigned char c) {
141 using namespace charinfo;
142 return (InfoTable[c] & (CHAR_UPPER|CHAR_LOWER|CHAR_PERIOD|CHAR_PUNCT|
143 CHAR_DIGIT|CHAR_UNDER|CHAR_RAWDEL|CHAR_SPACE)) != 0;
144}
145
146/// Return true if this is the body character of a C preprocessing number,
147/// which is [a-zA-Z0-9_.].
148LLVM_READONLY inline bool isPreprocessingNumberBody(unsigned char c) {
149 using namespace charinfo;
150 return (InfoTable[c] &
151 (CHAR_UPPER|CHAR_LOWER|CHAR_DIGIT|CHAR_UNDER|CHAR_PERIOD)) != 0;
152}
153
154/// Return true if this is the body character of a C++ raw string delimiter.
155LLVM_READONLY inline bool isRawStringDelimBody(unsigned char c) {
156 using namespace charinfo;
157 return (InfoTable[c] & (CHAR_UPPER|CHAR_LOWER|CHAR_PERIOD|
158 CHAR_DIGIT|CHAR_UNDER|CHAR_RAWDEL)) != 0;
159}
160
161
162/// Converts the given ASCII character to its lowercase equivalent.
163///
164/// If the character is not an uppercase character, it is returned as is.
165LLVM_READONLY inline char toLowercase(char c) {
166 if (isUppercase(c))
167 return c + 'a' - 'A';
168 return c;
169}
170
171/// Converts the given ASCII character to its uppercase equivalent.
172///
173/// If the character is not a lowercase character, it is returned as is.
174LLVM_READONLY inline char toUppercase(char c) {
175 if (isLowercase(c))
176 return c + 'A' - 'a';
177 return c;
178}
179
180
181/// Return true if this is a valid ASCII identifier.
182///
183/// Note that this is a very simple check; it does not accept UCNs as valid
184/// identifier characters.
185LLVM_READONLY inline bool isValidIdentifier(StringRef S,
186 bool AllowDollar = false) {
187 if (S.empty() || !isIdentifierHead(S[0], AllowDollar))
188 return false;
189
190 for (StringRef::iterator I = S.begin(), E = S.end(); I != E; ++I)
191 if (!isIdentifierBody(*I, AllowDollar))
192 return false;
193
194 return true;
195}
196
197} // end namespace clang
198
199#endif
200