1 | //! Intermediate representation for C/C++ functions and methods. |
2 | |
3 | use super::comp::MethodKind; |
4 | use super::context::{BindgenContext, TypeId}; |
5 | use super::dot::DotAttributes; |
6 | use super::item::Item; |
7 | use super::traversal::{EdgeKind, Trace, Tracer}; |
8 | use super::ty::TypeKind; |
9 | use crate::callbacks::{ItemInfo, ItemKind}; |
10 | use crate::clang::{self, ABIKind, Attribute}; |
11 | use crate::parse::{ClangSubItemParser, ParseError, ParseResult}; |
12 | use clang_sys::{self, CXCallingConv}; |
13 | |
14 | use quote::TokenStreamExt; |
15 | use std::io; |
16 | use std::str::FromStr; |
17 | |
18 | const RUST_DERIVE_FUNPTR_LIMIT: usize = 12; |
19 | |
20 | /// What kind of a function are we looking at? |
21 | #[derive (Debug, Copy, Clone, PartialEq, Eq)] |
22 | pub(crate) enum FunctionKind { |
23 | /// A plain, free function. |
24 | Function, |
25 | /// A method of some kind. |
26 | Method(MethodKind), |
27 | } |
28 | |
29 | impl FunctionKind { |
30 | /// Given a clang cursor, return the kind of function it represents, or |
31 | /// `None` otherwise. |
32 | pub(crate) fn from_cursor(cursor: &clang::Cursor) -> Option<FunctionKind> { |
33 | // FIXME(emilio): Deduplicate logic with `ir::comp`. |
34 | Some(match cursor.kind() { |
35 | clang_sys::CXCursor_FunctionDecl => FunctionKind::Function, |
36 | clang_sys::CXCursor_Constructor => { |
37 | FunctionKind::Method(MethodKind::Constructor) |
38 | } |
39 | clang_sys::CXCursor_Destructor => { |
40 | FunctionKind::Method(if cursor.method_is_virtual() { |
41 | MethodKind::VirtualDestructor { |
42 | pure_virtual: cursor.method_is_pure_virtual(), |
43 | } |
44 | } else { |
45 | MethodKind::Destructor |
46 | }) |
47 | } |
48 | clang_sys::CXCursor_CXXMethod => { |
49 | if cursor.method_is_virtual() { |
50 | FunctionKind::Method(MethodKind::Virtual { |
51 | pure_virtual: cursor.method_is_pure_virtual(), |
52 | }) |
53 | } else if cursor.method_is_static() { |
54 | FunctionKind::Method(MethodKind::Static) |
55 | } else { |
56 | FunctionKind::Method(MethodKind::Normal) |
57 | } |
58 | } |
59 | _ => return None, |
60 | }) |
61 | } |
62 | } |
63 | |
64 | /// The style of linkage |
65 | #[derive (Debug, Clone, Copy)] |
66 | pub(crate) enum Linkage { |
67 | /// Externally visible and can be linked against |
68 | External, |
69 | /// Not exposed externally. 'static inline' functions will have this kind of linkage |
70 | Internal, |
71 | } |
72 | |
73 | /// A function declaration, with a signature, arguments, and argument names. |
74 | /// |
75 | /// The argument names vector must be the same length as the ones in the |
76 | /// signature. |
77 | #[derive (Debug)] |
78 | pub(crate) struct Function { |
79 | /// The name of this function. |
80 | name: String, |
81 | |
82 | /// The mangled name, that is, the symbol. |
83 | mangled_name: Option<String>, |
84 | |
85 | /// The link name. If specified, overwrite mangled_name. |
86 | link_name: Option<String>, |
87 | |
88 | /// The ID pointing to the current function signature. |
89 | signature: TypeId, |
90 | |
91 | /// The kind of function this is. |
92 | kind: FunctionKind, |
93 | |
94 | /// The linkage of the function. |
95 | linkage: Linkage, |
96 | } |
97 | |
98 | impl Function { |
99 | /// Construct a new function. |
100 | pub(crate) fn new( |
101 | name: String, |
102 | mangled_name: Option<String>, |
103 | link_name: Option<String>, |
104 | signature: TypeId, |
105 | kind: FunctionKind, |
106 | linkage: Linkage, |
107 | ) -> Self { |
108 | Function { |
109 | name, |
110 | mangled_name, |
111 | link_name, |
112 | signature, |
113 | kind, |
114 | linkage, |
115 | } |
116 | } |
117 | |
118 | /// Get this function's name. |
119 | pub(crate) fn name(&self) -> &str { |
120 | &self.name |
121 | } |
122 | |
123 | /// Get this function's name. |
124 | pub(crate) fn mangled_name(&self) -> Option<&str> { |
125 | self.mangled_name.as_deref() |
126 | } |
127 | |
128 | /// Get this function's link name. |
129 | pub fn link_name(&self) -> Option<&str> { |
130 | self.link_name.as_deref() |
131 | } |
132 | |
133 | /// Get this function's signature type. |
134 | pub(crate) fn signature(&self) -> TypeId { |
135 | self.signature |
136 | } |
137 | |
138 | /// Get this function's kind. |
139 | pub(crate) fn kind(&self) -> FunctionKind { |
140 | self.kind |
141 | } |
142 | |
143 | /// Get this function's linkage. |
144 | pub(crate) fn linkage(&self) -> Linkage { |
145 | self.linkage |
146 | } |
147 | } |
148 | |
149 | impl DotAttributes for Function { |
150 | fn dot_attributes<W>( |
151 | &self, |
152 | _ctx: &BindgenContext, |
153 | out: &mut W, |
154 | ) -> io::Result<()> |
155 | where |
156 | W: io::Write, |
157 | { |
158 | if let Some(ref mangled: &String) = self.mangled_name { |
159 | let mangled: String = |
160 | mangled.chars().flat_map(|c: char| c.escape_default()).collect(); |
161 | writeln!( |
162 | out, |
163 | "<tr><td>mangled name</td><td> {}</td></tr>" , |
164 | mangled |
165 | )?; |
166 | } |
167 | |
168 | Ok(()) |
169 | } |
170 | } |
171 | |
172 | /// A valid rust ABI. |
173 | #[derive (Debug, Copy, Clone, Hash, Eq, PartialEq)] |
174 | pub enum Abi { |
175 | /// The default C ABI. |
176 | C, |
177 | /// The "stdcall" ABI. |
178 | Stdcall, |
179 | /// The "efiapi" ABI. |
180 | EfiApi, |
181 | /// The "fastcall" ABI. |
182 | Fastcall, |
183 | /// The "thiscall" ABI. |
184 | ThisCall, |
185 | /// The "vectorcall" ABI. |
186 | Vectorcall, |
187 | /// The "aapcs" ABI. |
188 | Aapcs, |
189 | /// The "win64" ABI. |
190 | Win64, |
191 | /// The "C-unwind" ABI. |
192 | CUnwind, |
193 | /// The "system" ABI. |
194 | System, |
195 | } |
196 | |
197 | impl FromStr for Abi { |
198 | type Err = String; |
199 | |
200 | fn from_str(s: &str) -> Result<Self, Self::Err> { |
201 | match s { |
202 | "C" => Ok(Self::C), |
203 | "stdcall" => Ok(Self::Stdcall), |
204 | "efiapi" => Ok(Self::EfiApi), |
205 | "fastcall" => Ok(Self::Fastcall), |
206 | "thiscall" => Ok(Self::ThisCall), |
207 | "vectorcall" => Ok(Self::Vectorcall), |
208 | "aapcs" => Ok(Self::Aapcs), |
209 | "win64" => Ok(Self::Win64), |
210 | "C-unwind" => Ok(Self::CUnwind), |
211 | "system" => Ok(Self::System), |
212 | _ => Err(format!("Invalid or unknown ABI {:?}" , s)), |
213 | } |
214 | } |
215 | } |
216 | |
217 | impl std::fmt::Display for Abi { |
218 | fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { |
219 | let s: &str = match *self { |
220 | Self::C => "C" , |
221 | Self::Stdcall => "stdcall" , |
222 | Self::EfiApi => "efiapi" , |
223 | Self::Fastcall => "fastcall" , |
224 | Self::ThisCall => "thiscall" , |
225 | Self::Vectorcall => "vectorcall" , |
226 | Self::Aapcs => "aapcs" , |
227 | Self::Win64 => "win64" , |
228 | Self::CUnwind => "C-unwind" , |
229 | Abi::System => "system" , |
230 | }; |
231 | |
232 | s.fmt(f) |
233 | } |
234 | } |
235 | |
236 | impl quote::ToTokens for Abi { |
237 | fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) { |
238 | let abi: String = self.to_string(); |
239 | tokens.append_all(iter:quote! { #abi }); |
240 | } |
241 | } |
242 | |
243 | /// An ABI extracted from a clang cursor. |
244 | #[derive (Debug, Copy, Clone)] |
245 | pub(crate) enum ClangAbi { |
246 | /// An ABI known by Rust. |
247 | Known(Abi), |
248 | /// An unknown or invalid ABI. |
249 | Unknown(CXCallingConv), |
250 | } |
251 | |
252 | impl ClangAbi { |
253 | /// Returns whether this Abi is known or not. |
254 | fn is_unknown(&self) -> bool { |
255 | matches!(*self, ClangAbi::Unknown(..)) |
256 | } |
257 | } |
258 | |
259 | impl quote::ToTokens for ClangAbi { |
260 | fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) { |
261 | match *self { |
262 | Self::Known(abi: Abi) => abi.to_tokens(tokens), |
263 | Self::Unknown(cc: i32) => panic!( |
264 | "Cannot turn unknown calling convention to tokens: {:?}" , |
265 | cc |
266 | ), |
267 | } |
268 | } |
269 | } |
270 | |
271 | /// A function signature. |
272 | #[derive (Debug)] |
273 | pub(crate) struct FunctionSig { |
274 | /// The name of this function signature. |
275 | name: String, |
276 | |
277 | /// The return type of the function. |
278 | return_type: TypeId, |
279 | |
280 | /// The type of the arguments, optionally with the name of the argument when |
281 | /// declared. |
282 | argument_types: Vec<(Option<String>, TypeId)>, |
283 | |
284 | /// Whether this function is variadic. |
285 | is_variadic: bool, |
286 | is_divergent: bool, |
287 | |
288 | /// Whether this function's return value must be used. |
289 | must_use: bool, |
290 | |
291 | /// The ABI of this function. |
292 | abi: ClangAbi, |
293 | } |
294 | |
295 | fn get_abi(cc: CXCallingConv) -> ClangAbi { |
296 | use clang_sys::*; |
297 | match cc { |
298 | CXCallingConv_Default => ClangAbi::Known(Abi::C), |
299 | CXCallingConv_C => ClangAbi::Known(Abi::C), |
300 | CXCallingConv_X86StdCall => ClangAbi::Known(Abi::Stdcall), |
301 | CXCallingConv_X86FastCall => ClangAbi::Known(Abi::Fastcall), |
302 | CXCallingConv_X86ThisCall => ClangAbi::Known(Abi::ThisCall), |
303 | CXCallingConv_X86VectorCall => ClangAbi::Known(Abi::Vectorcall), |
304 | CXCallingConv_AAPCS => ClangAbi::Known(Abi::Aapcs), |
305 | CXCallingConv_X86_64Win64 => ClangAbi::Known(Abi::Win64), |
306 | CXCallingConv_AArch64VectorCall => ClangAbi::Known(Abi::Vectorcall), |
307 | other: i32 => ClangAbi::Unknown(other), |
308 | } |
309 | } |
310 | |
311 | /// Get the mangled name for the cursor's referent. |
312 | pub(crate) fn cursor_mangling( |
313 | ctx: &BindgenContext, |
314 | cursor: &clang::Cursor, |
315 | ) -> Option<String> { |
316 | if !ctx.options().enable_mangling { |
317 | return None; |
318 | } |
319 | |
320 | // We early return here because libclang may crash in some case |
321 | // if we pass in a variable inside a partial specialized template. |
322 | // See rust-lang/rust-bindgen#67, and rust-lang/rust-bindgen#462. |
323 | if cursor.is_in_non_fully_specialized_template() { |
324 | return None; |
325 | } |
326 | |
327 | let is_itanium_abi = ctx.abi_kind() == ABIKind::GenericItanium; |
328 | let is_destructor = cursor.kind() == clang_sys::CXCursor_Destructor; |
329 | if let Ok(mut manglings) = cursor.cxx_manglings() { |
330 | while let Some(m) = manglings.pop() { |
331 | // Only generate the destructor group 1, see below. |
332 | if is_itanium_abi && is_destructor && !m.ends_with("D1Ev" ) { |
333 | continue; |
334 | } |
335 | |
336 | return Some(m); |
337 | } |
338 | } |
339 | |
340 | let mut mangling = cursor.mangling(); |
341 | if mangling.is_empty() { |
342 | return None; |
343 | } |
344 | |
345 | if is_itanium_abi && is_destructor { |
346 | // With old (3.8-) libclang versions, and the Itanium ABI, clang returns |
347 | // the "destructor group 0" symbol, which means that it'll try to free |
348 | // memory, which definitely isn't what we want. |
349 | // |
350 | // Explicitly force the destructor group 1 symbol. |
351 | // |
352 | // See http://refspecs.linuxbase.org/cxxabi-1.83.html#mangling-special |
353 | // for the reference, and http://stackoverflow.com/a/6614369/1091587 for |
354 | // a more friendly explanation. |
355 | // |
356 | // We don't need to do this for constructors since clang seems to always |
357 | // have returned the C1 constructor. |
358 | // |
359 | // FIXME(emilio): Can a legit symbol in other ABIs end with this string? |
360 | // I don't think so, but if it can this would become a linker error |
361 | // anyway, not an invalid free at runtime. |
362 | // |
363 | // TODO(emilio, #611): Use cpp_demangle if this becomes nastier with |
364 | // time. |
365 | if mangling.ends_with("D0Ev" ) { |
366 | let new_len = mangling.len() - 4; |
367 | mangling.truncate(new_len); |
368 | mangling.push_str("D1Ev" ); |
369 | } |
370 | } |
371 | |
372 | Some(mangling) |
373 | } |
374 | |
375 | fn args_from_ty_and_cursor( |
376 | ty: &clang::Type, |
377 | cursor: &clang::Cursor, |
378 | ctx: &mut BindgenContext, |
379 | ) -> Vec<(Option<String>, TypeId)> { |
380 | let cursor_args = cursor.args().unwrap_or_default().into_iter(); |
381 | let type_args = ty.args().unwrap_or_default().into_iter(); |
382 | |
383 | // Argument types can be found in either the cursor or the type, but argument names may only be |
384 | // found on the cursor. We often have access to both a type and a cursor for each argument, but |
385 | // in some cases we may only have one. |
386 | // |
387 | // Prefer using the type as the source of truth for the argument's type, but fall back to |
388 | // inspecting the cursor (this happens for Objective C interfaces). |
389 | // |
390 | // Prefer using the cursor for the argument's type, but fall back to using the parent's cursor |
391 | // (this happens for function pointer return types). |
392 | cursor_args |
393 | .map(Some) |
394 | .chain(std::iter::repeat(None)) |
395 | .zip(type_args.map(Some).chain(std::iter::repeat(None))) |
396 | .take_while(|(cur, ty)| cur.is_some() || ty.is_some()) |
397 | .map(|(arg_cur, arg_ty)| { |
398 | let name = arg_cur.map(|a| a.spelling()).and_then(|name| { |
399 | if name.is_empty() { |
400 | None |
401 | } else { |
402 | Some(name) |
403 | } |
404 | }); |
405 | |
406 | let cursor = arg_cur.unwrap_or(*cursor); |
407 | let ty = arg_ty.unwrap_or_else(|| cursor.cur_type()); |
408 | (name, Item::from_ty_or_ref(ty, cursor, None, ctx)) |
409 | }) |
410 | .collect() |
411 | } |
412 | |
413 | impl FunctionSig { |
414 | /// Get the function name. |
415 | pub(crate) fn name(&self) -> &str { |
416 | &self.name |
417 | } |
418 | |
419 | /// Construct a new function signature from the given Clang type. |
420 | pub(crate) fn from_ty( |
421 | ty: &clang::Type, |
422 | cursor: &clang::Cursor, |
423 | ctx: &mut BindgenContext, |
424 | ) -> Result<Self, ParseError> { |
425 | use clang_sys::*; |
426 | debug!("FunctionSig::from_ty {:?} {:?}" , ty, cursor); |
427 | |
428 | // Skip function templates |
429 | let kind = cursor.kind(); |
430 | if kind == CXCursor_FunctionTemplate { |
431 | return Err(ParseError::Continue); |
432 | } |
433 | |
434 | let spelling = cursor.spelling(); |
435 | |
436 | // Don't parse operatorxx functions in C++ |
437 | let is_operator = |spelling: &str| { |
438 | spelling.starts_with("operator" ) && |
439 | !clang::is_valid_identifier(spelling) |
440 | }; |
441 | if is_operator(&spelling) { |
442 | return Err(ParseError::Continue); |
443 | } |
444 | |
445 | // Constructors of non-type template parameter classes for some reason |
446 | // include the template parameter in their name. Just skip them, since |
447 | // we don't handle well non-type template parameters anyway. |
448 | if (kind == CXCursor_Constructor || kind == CXCursor_Destructor) && |
449 | spelling.contains('<' ) |
450 | { |
451 | return Err(ParseError::Continue); |
452 | } |
453 | |
454 | let cursor = if cursor.is_valid() { |
455 | *cursor |
456 | } else { |
457 | ty.declaration() |
458 | }; |
459 | |
460 | let mut args = match kind { |
461 | CXCursor_FunctionDecl | |
462 | CXCursor_Constructor | |
463 | CXCursor_CXXMethod | |
464 | CXCursor_ObjCInstanceMethodDecl | |
465 | CXCursor_ObjCClassMethodDecl => { |
466 | args_from_ty_and_cursor(ty, &cursor, ctx) |
467 | } |
468 | _ => { |
469 | // For non-CXCursor_FunctionDecl, visiting the cursor's children |
470 | // is the only reliable way to get parameter names. |
471 | let mut args = vec![]; |
472 | cursor.visit(|c| { |
473 | if c.kind() == CXCursor_ParmDecl { |
474 | let ty = |
475 | Item::from_ty_or_ref(c.cur_type(), c, None, ctx); |
476 | let name = c.spelling(); |
477 | let name = |
478 | if name.is_empty() { None } else { Some(name) }; |
479 | args.push((name, ty)); |
480 | } |
481 | CXChildVisit_Continue |
482 | }); |
483 | |
484 | if args.is_empty() { |
485 | // FIXME(emilio): Sometimes libclang doesn't expose the |
486 | // right AST for functions tagged as stdcall and such... |
487 | // |
488 | // https://bugs.llvm.org/show_bug.cgi?id=45919 |
489 | args_from_ty_and_cursor(ty, &cursor, ctx) |
490 | } else { |
491 | args |
492 | } |
493 | } |
494 | }; |
495 | |
496 | let (must_use, mut is_divergent) = |
497 | if ctx.options().enable_function_attribute_detection { |
498 | let [must_use, no_return, no_return_cpp] = cursor.has_attrs(&[ |
499 | Attribute::MUST_USE, |
500 | Attribute::NO_RETURN, |
501 | Attribute::NO_RETURN_CPP, |
502 | ]); |
503 | (must_use, no_return || no_return_cpp) |
504 | } else { |
505 | Default::default() |
506 | }; |
507 | |
508 | // Check if the type contains __attribute__((noreturn)) outside of parentheses. This is |
509 | // somewhat fragile, but it seems to be the only way to get at this information as of |
510 | // libclang 9. |
511 | let ty_spelling = ty.spelling(); |
512 | let has_attribute_noreturn = ty_spelling |
513 | .match_indices("__attribute__((noreturn))" ) |
514 | .any(|(i, _)| { |
515 | let depth = ty_spelling[..i] |
516 | .bytes() |
517 | .filter_map(|ch| match ch { |
518 | b'(' => Some(1), |
519 | b')' => Some(-1), |
520 | _ => None, |
521 | }) |
522 | .sum::<isize>(); |
523 | depth == 0 |
524 | }); |
525 | is_divergent = is_divergent || has_attribute_noreturn; |
526 | |
527 | let is_method = kind == CXCursor_CXXMethod; |
528 | let is_constructor = kind == CXCursor_Constructor; |
529 | let is_destructor = kind == CXCursor_Destructor; |
530 | if (is_constructor || is_destructor || is_method) && |
531 | cursor.lexical_parent() != cursor.semantic_parent() |
532 | { |
533 | // Only parse constructors once. |
534 | return Err(ParseError::Continue); |
535 | } |
536 | |
537 | if is_method || is_constructor || is_destructor { |
538 | let is_const = is_method && cursor.method_is_const(); |
539 | let is_virtual = is_method && cursor.method_is_virtual(); |
540 | let is_static = is_method && cursor.method_is_static(); |
541 | if !is_static && !is_virtual { |
542 | let parent = cursor.semantic_parent(); |
543 | let class = Item::parse(parent, None, ctx) |
544 | .expect("Expected to parse the class" ); |
545 | // The `class` most likely is not finished parsing yet, so use |
546 | // the unchecked variant. |
547 | let class = class.as_type_id_unchecked(); |
548 | |
549 | let class = if is_const { |
550 | let const_class_id = ctx.next_item_id(); |
551 | ctx.build_const_wrapper( |
552 | const_class_id, |
553 | class, |
554 | None, |
555 | &parent.cur_type(), |
556 | ) |
557 | } else { |
558 | class |
559 | }; |
560 | |
561 | let ptr = |
562 | Item::builtin_type(TypeKind::Pointer(class), false, ctx); |
563 | args.insert(0, (Some("this" .into()), ptr)); |
564 | } else if is_virtual { |
565 | let void = Item::builtin_type(TypeKind::Void, false, ctx); |
566 | let ptr = |
567 | Item::builtin_type(TypeKind::Pointer(void), false, ctx); |
568 | args.insert(0, (Some("this" .into()), ptr)); |
569 | } |
570 | } |
571 | |
572 | let ty_ret_type = if kind == CXCursor_ObjCInstanceMethodDecl || |
573 | kind == CXCursor_ObjCClassMethodDecl |
574 | { |
575 | ty.ret_type() |
576 | .or_else(|| cursor.ret_type()) |
577 | .ok_or(ParseError::Continue)? |
578 | } else { |
579 | ty.ret_type().ok_or(ParseError::Continue)? |
580 | }; |
581 | |
582 | let ret = if is_constructor && ctx.is_target_wasm32() { |
583 | // Constructors in Clang wasm32 target return a pointer to the object |
584 | // being constructed. |
585 | let void = Item::builtin_type(TypeKind::Void, false, ctx); |
586 | Item::builtin_type(TypeKind::Pointer(void), false, ctx) |
587 | } else { |
588 | Item::from_ty_or_ref(ty_ret_type, cursor, None, ctx) |
589 | }; |
590 | |
591 | // Clang plays with us at "find the calling convention", see #549 and |
592 | // co. This seems to be a better fix than that commit. |
593 | let mut call_conv = ty.call_conv(); |
594 | if let Some(ty) = cursor.cur_type().canonical_type().pointee_type() { |
595 | let cursor_call_conv = ty.call_conv(); |
596 | if cursor_call_conv != CXCallingConv_Invalid { |
597 | call_conv = cursor_call_conv; |
598 | } |
599 | } |
600 | |
601 | let abi = get_abi(call_conv); |
602 | |
603 | if abi.is_unknown() { |
604 | warn!("Unknown calling convention: {:?}" , call_conv); |
605 | } |
606 | |
607 | Ok(Self { |
608 | name: spelling, |
609 | return_type: ret, |
610 | argument_types: args, |
611 | is_variadic: ty.is_variadic(), |
612 | is_divergent, |
613 | must_use, |
614 | abi, |
615 | }) |
616 | } |
617 | |
618 | /// Get this function signature's return type. |
619 | pub(crate) fn return_type(&self) -> TypeId { |
620 | self.return_type |
621 | } |
622 | |
623 | /// Get this function signature's argument (name, type) pairs. |
624 | pub(crate) fn argument_types(&self) -> &[(Option<String>, TypeId)] { |
625 | &self.argument_types |
626 | } |
627 | |
628 | /// Get this function signature's ABI. |
629 | pub(crate) fn abi( |
630 | &self, |
631 | ctx: &BindgenContext, |
632 | name: Option<&str>, |
633 | ) -> crate::codegen::error::Result<ClangAbi> { |
634 | // FIXME (pvdrz): Try to do this check lazily instead. Maybe store the ABI inside `ctx` |
635 | // instead?. |
636 | let abi = if let Some(name) = name { |
637 | if let Some((abi, _)) = ctx |
638 | .options() |
639 | .abi_overrides |
640 | .iter() |
641 | .find(|(_, regex_set)| regex_set.matches(name)) |
642 | { |
643 | ClangAbi::Known(*abi) |
644 | } else { |
645 | self.abi |
646 | } |
647 | } else if let Some((abi, _)) = ctx |
648 | .options() |
649 | .abi_overrides |
650 | .iter() |
651 | .find(|(_, regex_set)| regex_set.matches(&self.name)) |
652 | { |
653 | ClangAbi::Known(*abi) |
654 | } else { |
655 | self.abi |
656 | }; |
657 | |
658 | match abi { |
659 | ClangAbi::Known(Abi::ThisCall) |
660 | if !ctx.options().rust_features().thiscall_abi => |
661 | { |
662 | Err(crate::codegen::error::Error::UnsupportedAbi("thiscall" )) |
663 | } |
664 | ClangAbi::Known(Abi::Vectorcall) |
665 | if !ctx.options().rust_features().vectorcall_abi => |
666 | { |
667 | Err(crate::codegen::error::Error::UnsupportedAbi("vectorcall" )) |
668 | } |
669 | ClangAbi::Known(Abi::CUnwind) |
670 | if !ctx.options().rust_features().c_unwind_abi => |
671 | { |
672 | Err(crate::codegen::error::Error::UnsupportedAbi("C-unwind" )) |
673 | } |
674 | ClangAbi::Known(Abi::EfiApi) |
675 | if !ctx.options().rust_features().abi_efiapi => |
676 | { |
677 | Err(crate::codegen::error::Error::UnsupportedAbi("efiapi" )) |
678 | } |
679 | ClangAbi::Known(Abi::Win64) if self.is_variadic() => { |
680 | Err(crate::codegen::error::Error::UnsupportedAbi("Win64" )) |
681 | } |
682 | abi => Ok(abi), |
683 | } |
684 | } |
685 | |
686 | /// Is this function signature variadic? |
687 | pub(crate) fn is_variadic(&self) -> bool { |
688 | // Clang reports some functions as variadic when they *might* be |
689 | // variadic. We do the argument check because rust doesn't codegen well |
690 | // variadic functions without an initial argument. |
691 | self.is_variadic && !self.argument_types.is_empty() |
692 | } |
693 | |
694 | /// Must this function's return value be used? |
695 | pub(crate) fn must_use(&self) -> bool { |
696 | self.must_use |
697 | } |
698 | |
699 | /// Are function pointers with this signature able to derive Rust traits? |
700 | /// Rust only supports deriving traits for function pointers with a limited |
701 | /// number of parameters and a couple ABIs. |
702 | /// |
703 | /// For more details, see: |
704 | /// |
705 | /// * <https://github.com/rust-lang/rust-bindgen/issues/547>, |
706 | /// * <https://github.com/rust-lang/rust/issues/38848>, |
707 | /// * and <https://github.com/rust-lang/rust/issues/40158> |
708 | pub(crate) fn function_pointers_can_derive(&self) -> bool { |
709 | if self.argument_types.len() > RUST_DERIVE_FUNPTR_LIMIT { |
710 | return false; |
711 | } |
712 | |
713 | matches!(self.abi, ClangAbi::Known(Abi::C) | ClangAbi::Unknown(..)) |
714 | } |
715 | |
716 | /// Whether this function has attributes marking it as divergent. |
717 | pub(crate) fn is_divergent(&self) -> bool { |
718 | self.is_divergent |
719 | } |
720 | } |
721 | |
722 | impl ClangSubItemParser for Function { |
723 | fn parse( |
724 | cursor: clang::Cursor, |
725 | context: &mut BindgenContext, |
726 | ) -> Result<ParseResult<Self>, ParseError> { |
727 | use clang_sys::*; |
728 | |
729 | let kind = match FunctionKind::from_cursor(&cursor) { |
730 | None => return Err(ParseError::Continue), |
731 | Some(k) => k, |
732 | }; |
733 | |
734 | debug!("Function::parse( {:?}, {:?})" , cursor, cursor.cur_type()); |
735 | let visibility = cursor.visibility(); |
736 | if visibility != CXVisibility_Default { |
737 | return Err(ParseError::Continue); |
738 | } |
739 | |
740 | if cursor.access_specifier() == CX_CXXPrivate { |
741 | return Err(ParseError::Continue); |
742 | } |
743 | |
744 | let linkage = cursor.linkage(); |
745 | let linkage = match linkage { |
746 | CXLinkage_External | CXLinkage_UniqueExternal => Linkage::External, |
747 | CXLinkage_Internal => Linkage::Internal, |
748 | _ => return Err(ParseError::Continue), |
749 | }; |
750 | |
751 | if cursor.is_inlined_function() || |
752 | cursor |
753 | .definition() |
754 | .map_or(false, |x| x.is_inlined_function()) |
755 | { |
756 | if !context.options().generate_inline_functions && |
757 | !context.options().wrap_static_fns |
758 | { |
759 | return Err(ParseError::Continue); |
760 | } |
761 | |
762 | if cursor.is_deleted_function() { |
763 | return Err(ParseError::Continue); |
764 | } |
765 | |
766 | // We cannot handle `inline` functions that are not `static`. |
767 | if context.options().wrap_static_fns && |
768 | cursor.is_inlined_function() && |
769 | matches!(linkage, Linkage::External) |
770 | { |
771 | return Err(ParseError::Continue); |
772 | } |
773 | } |
774 | |
775 | // Grab the signature using Item::from_ty. |
776 | let sig = Item::from_ty(&cursor.cur_type(), cursor, None, context)?; |
777 | |
778 | let mut name = cursor.spelling(); |
779 | assert!(!name.is_empty(), "Empty function name?" ); |
780 | |
781 | if cursor.kind() == CXCursor_Destructor { |
782 | // Remove the leading `~`. The alternative to this is special-casing |
783 | // code-generation for destructor functions, which seems less than |
784 | // ideal. |
785 | if name.starts_with('~' ) { |
786 | name.remove(0); |
787 | } |
788 | |
789 | // Add a suffix to avoid colliding with constructors. This would be |
790 | // technically fine (since we handle duplicated functions/methods), |
791 | // but seems easy enough to handle it here. |
792 | name.push_str("_destructor" ); |
793 | } |
794 | if let Some(nm) = context.options().last_callback(|callbacks| { |
795 | callbacks.generated_name_override(ItemInfo { |
796 | name: name.as_str(), |
797 | kind: ItemKind::Function, |
798 | }) |
799 | }) { |
800 | name = nm; |
801 | } |
802 | assert!(!name.is_empty(), "Empty function name." ); |
803 | |
804 | let mangled_name = cursor_mangling(context, &cursor); |
805 | |
806 | let link_name = context.options().last_callback(|callbacks| { |
807 | callbacks.generated_link_name_override(ItemInfo { |
808 | name: name.as_str(), |
809 | kind: ItemKind::Function, |
810 | }) |
811 | }); |
812 | |
813 | let function = Self::new( |
814 | name.clone(), |
815 | mangled_name, |
816 | link_name, |
817 | sig, |
818 | kind, |
819 | linkage, |
820 | ); |
821 | |
822 | Ok(ParseResult::New(function, Some(cursor))) |
823 | } |
824 | } |
825 | |
826 | impl Trace for FunctionSig { |
827 | type Extra = (); |
828 | |
829 | fn trace<T>(&self, _: &BindgenContext, tracer: &mut T, _: &()) |
830 | where |
831 | T: Tracer, |
832 | { |
833 | tracer.visit_kind(self.return_type().into(), kind:EdgeKind::FunctionReturn); |
834 | |
835 | for &(_, ty: TypeId) in self.argument_types() { |
836 | tracer.visit_kind(item:ty.into(), kind:EdgeKind::FunctionParameter); |
837 | } |
838 | } |
839 | } |
840 | |