1// Take a look at the license at the top of the repository in the LICENSE file.
2
3#[cfg(feature = "debug")]
4#[doc(hidden)]
5#[allow(unused)]
6macro_rules! sysinfo_debug {
7 ($($x:tt)*) => {{
8 eprintln!($($x)*);
9 }}
10}
11
12#[cfg(not(feature = "debug"))]
13#[doc(hidden)]
14#[allow(unused)]
15macro_rules! sysinfo_debug {
16 ($($x:tt)*) => {{}};
17}
18
19#[cfg(feature = "system")]
20macro_rules! declare_signals {
21 ($kind:ty, _ => None,) => (
22 use crate::Signal;
23
24 pub(crate) const fn supported_signals() -> &'static [Signal] {
25 &[]
26 }
27 );
28
29 ($kind:ty, $(Signal::$signal:ident => $map:expr,)+ _ => None,) => (
30 use crate::Signal;
31
32 pub(crate) const fn supported_signals() -> &'static [Signal] {
33 &[$(Signal::$signal,)*]
34 }
35
36 #[inline]
37 pub(crate) fn convert_signal(s: Signal) -> Option<$kind> {
38 match s {
39 $(Signal::$signal => Some($map),)*
40 _ => None,
41 }
42 }
43 );
44
45 ($kind:ty, $(Signal::$signal:ident => $map:expr,)+) => (
46 use crate::Signal;
47
48 pub(crate) const fn supported_signals() -> &'static [Signal] {
49 &[$(Signal::$signal,)*]
50 }
51
52 #[inline]
53 pub(crate) fn convert_signal(s: Signal) -> Option<$kind> {
54 match s {
55 $(Signal::$signal => Some($map),)*
56 }
57 }
58 )
59}
60
61#[cfg(all(unix, not(feature = "unknown-ci")))]
62#[allow(unused_macros)]
63macro_rules! retry_eintr {
64 (set_to_0 => $($t:tt)+) => {{
65 let errno = crate::unix::libc_errno();
66 if !errno.is_null() {
67 *errno = 0;
68 }
69 retry_eintr!($($t)+)
70 }};
71 ($errno_value:ident => $($t:tt)+) => {{
72 loop {
73 let ret = $($t)+;
74 if ret < 0 {
75 let tmp = std::io::Error::last_os_error();
76 if tmp.kind() == std::io::ErrorKind::Interrupted {
77 continue;
78 }
79 $errno_value = tmp.raw_os_error().unwrap_or(0);
80 }
81 break ret;
82 }
83 }};
84 ($($t:tt)+) => {{
85 loop {
86 let ret = $($t)+;
87 if ret < 0 && std::io::Error::last_os_error().kind() == std::io::ErrorKind::Interrupted {
88 continue;
89 }
90 break ret;
91 }
92 }};
93}
94
95//FIXME: Remove this code if https://github.com/rust-lang/cfg-if/pull/78 is ever merged.
96macro_rules! cfg_if {
97 // match if/else chains with a final `else`
98 (
99 $(
100 if #[cfg( $i_meta:meta )] { $( $i_tokens:tt )* }
101 ) else+
102 else { $( $e_tokens:tt )* }
103 ) => {
104 cfg_if! {
105 @__items () ;
106 $(
107 (( $i_meta ) ( $( $i_tokens )* )) ,
108 )+
109 (() ( $( $e_tokens )* )) ,
110 }
111 };
112
113 // Allow to multiple conditions in a same call.
114 (
115 $(
116 if #[cfg( $i_meta:meta )] { $( $i_tokens:tt )* }
117 ) else+
118 else { $( $e_tokens:tt )* }
119 if $($extra_conditions:tt)+
120 ) => {
121 cfg_if! {
122 @__items () ;
123 $(
124 (( $i_meta ) ( $( $i_tokens )* )) ,
125 )+
126 (() ( $( $e_tokens )* )) ,
127 }
128 cfg_if! {
129 if $($extra_conditions)+
130 }
131 };
132
133 // match if/else chains lacking a final `else`
134 (
135 if #[cfg( $i_meta:meta )] { $( $i_tokens:tt )* }
136 $(
137 else if #[cfg( $e_meta:meta )] { $( $e_tokens:tt )* }
138 )*
139 ) => {
140 cfg_if! {
141 @__items () ;
142 (( $i_meta ) ( $( $i_tokens )* )) ,
143 $(
144 (( $e_meta ) ( $( $e_tokens )* )) ,
145 )*
146 }
147 };
148
149 // Allow to multiple conditions in a same call.
150 (
151 if #[cfg( $i_meta:meta )] { $( $i_tokens:tt )* }
152 $(
153 else if #[cfg( $e_meta:meta )] { $( $e_tokens:tt )* }
154 )*
155 if $($extra_conditions:tt)+
156 ) => {
157 cfg_if! {
158 @__items () ;
159 (( $i_meta ) ( $( $i_tokens )* )) ,
160 $(
161 (( $e_meta ) ( $( $e_tokens )* )) ,
162 )*
163 }
164 cfg_if! {
165 if $($extra_conditions)+
166 }
167 };
168
169 // Internal and recursive macro to emit all the items
170 //
171 // Collects all the previous cfgs in a list at the beginning, so they can be
172 // negated. After the semicolon is all the remaining items.
173 (@__items ( $( $_:meta , )* ) ; ) => {};
174 (
175 @__items ( $( $no:meta , )* ) ;
176 (( $( $yes:meta )? ) ( $( $tokens:tt )* )) ,
177 $( $rest:tt , )*
178 ) => {
179 // Emit all items within one block, applying an appropriate #[cfg]. The
180 // #[cfg] will require all `$yes` matchers specified and must also negate
181 // all previous matchers.
182 #[cfg(all(
183 $( $yes , )?
184 not(any( $( $no ),* ))
185 ))]
186 cfg_if! { @__identity $( $tokens )* }
187
188 // Recurse to emit all other items in `$rest`, and when we do so add all
189 // our `$yes` matchers to the list of `$no` matchers as future emissions
190 // will have to negate everything we just matched as well.
191 cfg_if! {
192 @__items ( $( $no , )* $( $yes , )? ) ;
193 $( $rest , )*
194 }
195 };
196
197 // Internal macro to make __apply work out right for different match types,
198 // because of how macros match/expand stuff.
199 (@__identity $( $tokens:tt )* ) => {
200 $( $tokens )*
201 };
202}
203
204#[cfg(test)]
205#[allow(unexpected_cfgs)]
206mod tests {
207 cfg_if! {
208 if #[cfg(test)] {
209 use core::option::Option as Option2;
210 fn works1() -> Option2<u32> { Some(1) }
211 } else {
212 fn works1() -> Option<u32> { None }
213 }
214 }
215
216 cfg_if! {
217 if #[cfg(foo)] {
218 fn works2() -> bool { false }
219 } else if #[cfg(test)] {
220 fn works2() -> bool { true }
221 } else {
222 fn works2() -> bool { false }
223 }
224 }
225
226 cfg_if! {
227 if #[cfg(foo)] {
228 fn works3() -> bool { false }
229 } else {
230 fn works3() -> bool { true }
231 }
232 }
233
234 cfg_if! {
235 if #[cfg(test)] {
236 use core::option::Option as Option3;
237 fn works4() -> Option3<u32> { Some(1) }
238 }
239 }
240
241 cfg_if! {
242 if #[cfg(foo)] {
243 fn works5() -> bool { false }
244 } else if #[cfg(test)] {
245 fn works5() -> bool { true }
246 }
247 }
248
249 cfg_if! {
250 if #[cfg(foo)] {
251 fn works6() -> bool { false }
252 } else if #[cfg(test)] {
253 fn works6() -> bool { true }
254 }
255 if #[cfg(test)] {
256 fn works7() -> bool { true }
257 } else {
258 fn works7() -> bool { false }
259 }
260 }
261
262 cfg_if! {
263 if #[cfg(test)] {
264 fn works8() -> bool { true }
265 } else if #[cfg(foo)] {
266 fn works8() -> bool { false }
267 }
268 if #[cfg(foo)] {
269 fn works9() -> bool { false }
270 } else if #[cfg(test)] {
271 fn works9() -> bool { true }
272 }
273 }
274
275 #[test]
276 fn it_works() {
277 assert!(works1().is_some());
278 assert!(works2());
279 assert!(works3());
280 assert!(works4().is_some());
281 assert!(works5());
282 assert!(works6());
283 assert!(works7());
284 assert!(works8());
285 assert!(works9());
286 }
287
288 #[test]
289 #[allow(clippy::assertions_on_constants)]
290 fn test_usage_within_a_function() {
291 cfg_if! {if #[cfg(debug_assertions)] {
292 // we want to put more than one thing here to make sure that they
293 // all get configured properly.
294 assert!(cfg!(debug_assertions));
295 assert_eq!(4, 2+2);
296 } else {
297 assert!(works1().is_some());
298 assert_eq!(10, 5+5);
299 }}
300 }
301
302 #[allow(dead_code)]
303 trait Trait {
304 fn blah(&self);
305 }
306
307 #[allow(dead_code)]
308 struct Struct;
309
310 impl Trait for Struct {
311 cfg_if! {
312 if #[cfg(feature = "blah")] {
313 fn blah(&self) {
314 unimplemented!();
315 }
316 } else {
317 fn blah(&self) {
318 unimplemented!();
319 }
320 }
321 }
322 }
323}
324