1use std::path::Path;
34
35use crate::walk::{filter_dirs, walk};
36
37const EXCEPTION_PATHS: &[&str] = &[
39 "library/compiler-builtins",
40 "library/windows_targets",
41 "library/panic_abort",
42 "library/panic_unwind",
43 "library/unwind",
44 "library/rtstartup", "library/test", "library/core/src/ffi/va_list.rs",
52 "library/core/src/ffi/mod.rs",
54 "library/core/src/ffi/primitives.rs",
55 "library/std/src/sys", "library/std/src/os", "library/std/src/io/copy.rs",
60 "library/std/src/io/stdio.rs",
61 "library/std/src/lib.rs", "library/std/src/path.rs",
63 "library/std/src/sys_common", "library/std/src/net/test.rs", "library/std/src/io/error.rs", ];
67
68pub fn check(path: &Path, bad: &mut bool) {
69 let mut saw_target_arch = false;
71 let mut saw_cfg_bang = false;
72 walk(path, |path, _is_dir| filter_dirs(path), &mut |entry, contents| {
73 let file = entry.path();
74 let filestr = file.to_string_lossy().replace("\\", "/");
75 if !filestr.ends_with(".rs") {
76 return;
77 }
78
79 let is_exception_path = EXCEPTION_PATHS.iter().any(|s| filestr.contains(&**s));
80 if is_exception_path {
81 return;
82 }
83
84 if filestr.contains("tests") || filestr.contains("benches") {
86 return;
87 }
88
89 check_cfgs(contents, &file, bad, &mut saw_target_arch, &mut saw_cfg_bang);
90 });
91
92 assert!(saw_target_arch);
93 assert!(saw_cfg_bang);
94}
95
96fn check_cfgs(
97 contents: &str,
98 file: &Path,
99 bad: &mut bool,
100 saw_target_arch: &mut bool,
101 saw_cfg_bang: &mut bool,
102) {
103 let cfgs = parse_cfgs(contents);
105
106 let mut line_numbers: Option<Vec<usize>> = None;
107 let mut err = |idx: usize, cfg: &str| {
108 if line_numbers.is_none() {
109 line_numbers = Some(contents.match_indices('\n').map(|(i, _)| i).collect());
110 }
111 let line_numbers = line_numbers.as_ref().expect("");
112 let line = match line_numbers.binary_search(&idx) {
113 Ok(_) => unreachable!(),
114 Err(i) => i + 1,
115 };
116 tidy_error!(bad, "{}:{}: platform-specific cfg: {}", file.display(), line, cfg);
117 };
118
119 for (idx, cfg) in cfgs {
120 if !*saw_target_arch && cfg.contains("target_arch") {
122 *saw_target_arch = true
123 }
124 if !*saw_cfg_bang && cfg.contains("cfg!") {
125 *saw_cfg_bang = true
126 }
127
128 let contains_platform_specific_cfg = cfg.contains("target_os")
129 || cfg.contains("target_env")
130 || cfg.contains("target_abi")
131 || cfg.contains("target_vendor")
132 || cfg.contains("target_family")
133 || cfg.contains("unix")
134 || cfg.contains("windows");
135
136 if !contains_platform_specific_cfg {
137 continue;
138 }
139
140 let preceded_by_doc_comment = {
141 let pre_contents = &contents[..idx];
142 let pre_newline = pre_contents.rfind('\n');
143 let pre_doc_comment = pre_contents.rfind("///");
144 match (pre_newline, pre_doc_comment) {
145 (Some(n), Some(c)) => n < c,
146 (None, Some(_)) => true,
147 (_, None) => false,
148 }
149 };
150
151 if preceded_by_doc_comment {
152 continue;
153 }
154
155 if cfg.contains("test") {
157 continue;
158 }
159
160 err(idx, cfg);
161 }
162}
163
164fn parse_cfgs(contents: &str) -> Vec<(usize, &str)> {
165 let candidate_cfgs = contents.match_indices("cfg");
166 let candidate_cfg_idxs = candidate_cfgs.map(|(i, _)| i);
167 let cfgs = candidate_cfg_idxs.filter(|i| {
170 let pre_idx = i.saturating_sub(1);
171 let succeeds_non_ident = !contents
172 .as_bytes()
173 .get(pre_idx)
174 .cloned()
175 .map(char::from)
176 .map(char::is_alphanumeric)
177 .unwrap_or(false);
178 let contents_after = &contents[*i..];
179 let first_paren = contents_after.find('(');
180 let paren_idx = first_paren.map(|ip| i + ip);
181 let preceeds_whitespace_and_paren = paren_idx
182 .map(|ip| {
183 let maybe_space = &contents[*i + "cfg".len()..ip];
184 maybe_space.chars().all(|c| char::is_whitespace(c) || c == '!')
185 })
186 .unwrap_or(false);
187
188 succeeds_non_ident && preceeds_whitespace_and_paren
189 });
190
191 cfgs.flat_map(|i| {
192 let mut depth = 0;
193 let contents_from = &contents[i..];
194 for (j, byte) in contents_from.bytes().enumerate() {
195 match byte {
196 b'(' => {
197 depth += 1;
198 }
199 b')' => {
200 depth -= 1;
201 if depth == 0 {
202 return Some((i, &contents_from[..=j]));
203 }
204 }
205 _ => {}
206 }
207 }
208
209 None
212 })
213 .collect()
214}