blob: 6dbb601201118a780105accdd89c2d9b215bda8a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
|
/*
* Copyright (c) 2021, Itamar S. <itamar8910@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "Preprocessor.h"
#include <AK/Assertions.h>
#include <AK/GenericLexer.h>
#include <AK/StringBuilder.h>
#include <ctype.h>
namespace Cpp {
Preprocessor::Preprocessor(const String& filename, const StringView& program)
: m_filename(filename)
, m_program(program)
{
m_lines = m_program.split_view('\n', true);
}
const String& Preprocessor::process()
{
for (; m_line_index < m_lines.size(); ++m_line_index) {
auto& line = m_lines[m_line_index];
bool include_in_processed_text = false;
if (line.starts_with("#")) {
auto keyword = handle_preprocessor_line(line);
if (m_options.keep_include_statements && keyword == "include")
include_in_processed_text = true;
} else if (m_state == State::Normal) {
include_in_processed_text = true;
}
if (include_in_processed_text) {
m_builder.append(line);
}
m_builder.append("\n");
}
m_processed_text = m_builder.to_string();
return m_processed_text;
}
static void consume_whitespace(GenericLexer& lexer)
{
lexer.ignore_while([](char ch) { return isspace(ch); });
if (lexer.peek() == '/' && lexer.peek(1) == '/')
lexer.ignore_until([](char ch) { return ch == '\n'; });
}
Preprocessor::PreprocessorKeyword Preprocessor::handle_preprocessor_line(const StringView& line)
{
GenericLexer lexer(line);
consume_whitespace(lexer);
lexer.consume_specific('#');
consume_whitespace(lexer);
auto keyword = lexer.consume_until(' ');
if (keyword.is_empty() || keyword.is_null() || keyword.is_whitespace())
return {};
handle_preprocessor_keyword(keyword, lexer);
return keyword;
}
void Preprocessor::handle_preprocessor_keyword(const StringView& keyword, GenericLexer& line_lexer)
{
if (keyword == "include") {
consume_whitespace(line_lexer);
m_included_paths.append(line_lexer.consume_all());
return;
}
if (keyword == "else") {
VERIFY(m_current_depth > 0);
if (m_depths_of_not_taken_branches.contains_slow(m_current_depth - 1)) {
m_depths_of_not_taken_branches.remove_all_matching([this](auto x) { return x == m_current_depth - 1; });
m_state = State::Normal;
}
if (m_depths_of_taken_branches.contains_slow(m_current_depth - 1)) {
m_state = State::SkipElseBranch;
}
return;
}
if (keyword == "endif") {
VERIFY(m_current_depth > 0);
--m_current_depth;
if (m_depths_of_not_taken_branches.contains_slow(m_current_depth)) {
m_depths_of_not_taken_branches.remove_all_matching([this](auto x) { return x == m_current_depth; });
}
if (m_depths_of_taken_branches.contains_slow(m_current_depth)) {
m_depths_of_taken_branches.remove_all_matching([this](auto x) { return x == m_current_depth; });
}
m_state = State::Normal;
return;
}
if (keyword == "define") {
if (m_state == State::Normal) {
auto key = line_lexer.consume_until(' ');
consume_whitespace(line_lexer);
DefinedValue value;
value.filename = m_filename;
value.line = m_line_index;
auto string_value = line_lexer.consume_all();
if (!string_value.is_empty())
value.value = string_value;
m_definitions.set(key, value);
}
return;
}
if (keyword == "undef") {
if (m_state == State::Normal) {
auto key = line_lexer.consume_until(' ');
line_lexer.consume_all();
m_definitions.remove(key);
}
return;
}
if (keyword == "ifdef") {
++m_current_depth;
if (m_state == State::Normal) {
auto key = line_lexer.consume_until(' ');
if (m_definitions.contains(key)) {
m_depths_of_taken_branches.append(m_current_depth - 1);
return;
} else {
m_depths_of_not_taken_branches.append(m_current_depth - 1);
m_state = State::SkipIfBranch;
return;
}
}
return;
}
if (keyword == "ifndef") {
++m_current_depth;
if (m_state == State::Normal) {
auto key = line_lexer.consume_until(' ');
if (!m_definitions.contains(key)) {
m_depths_of_taken_branches.append(m_current_depth - 1);
return;
} else {
m_depths_of_not_taken_branches.append(m_current_depth - 1);
m_state = State::SkipIfBranch;
return;
}
}
return;
}
if (keyword == "if") {
++m_current_depth;
if (m_state == State::Normal) {
// FIXME: Implement #if logic
// We currently always take #if branches.
m_depths_of_taken_branches.append(m_current_depth - 1);
}
return;
}
if (keyword == "elif") {
VERIFY(m_current_depth > 0);
// FIXME: Evaluate the elif expression
// We currently always treat the expression in #elif as true.
if (m_depths_of_not_taken_branches.contains_slow(m_current_depth - 1) /* && should_take*/) {
m_depths_of_not_taken_branches.remove_all_matching([this](auto x) { return x == m_current_depth - 1; });
m_state = State::Normal;
}
if (m_depths_of_taken_branches.contains_slow(m_current_depth - 1)) {
m_state = State::SkipElseBranch;
}
return;
}
if (keyword == "pragma") {
line_lexer.consume_all();
return;
}
if (!m_options.ignore_unsupported_keywords) {
dbgln("Unsupported preprocessor keyword: {}", keyword);
VERIFY_NOT_REACHED();
}
}
const String& Preprocessor::processed_text()
{
VERIFY(!m_processed_text.is_null());
return m_processed_text;
}
};
|
