1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE>
5 // or the MIT license <LICENSE-MIT>, at your option.
6 // You may not use this file except in accordance with one or both of these
9 //! Printing logic for basic blocks of Rust-mapped code - parts of functions and declarations but
10 //! not the full mapping logic.
15 use proc_macro2::TokenTree;
16 use quote::format_ident;
20 /// Writes out a C++ wrapper class for the given type, which contains various utilities to access
21 /// the underlying C-mapped type safely avoiding some common memory management issues by handling
22 /// resource-freeing and prevending accidental raw copies.
23 pub fn write_cpp_wrapper(cpp_header_file: &mut File, ty: &str, has_destructor: bool) {
24 writeln!(cpp_header_file, "class {} {{", ty).unwrap();
25 writeln!(cpp_header_file, "private:").unwrap();
26 writeln!(cpp_header_file, "\tLDK{} self;", ty).unwrap();
27 writeln!(cpp_header_file, "public:").unwrap();
28 writeln!(cpp_header_file, "\t{}(const {}&) = delete;", ty, ty).unwrap();
29 writeln!(cpp_header_file, "\t{}({}&& o) : self(o.self) {{ memset(&o, 0, sizeof({})); }}", ty, ty, ty).unwrap();
30 writeln!(cpp_header_file, "\t{}(LDK{}&& m_self) : self(m_self) {{ memset(&m_self, 0, sizeof(LDK{})); }}", ty, ty, ty).unwrap();
31 writeln!(cpp_header_file, "\toperator LDK{}() && {{ LDK{} res = self; memset(&self, 0, sizeof(LDK{})); return res; }}", ty, ty, ty).unwrap();
33 writeln!(cpp_header_file, "\t~{}() {{ {}_free(self); }}", ty, ty).unwrap();
34 writeln!(cpp_header_file, "\t{}& operator=({}&& o) {{ {}_free(self); self = o.self; memset(&o, 0, sizeof({})); return *this; }}", ty, ty, ty, ty).unwrap();
36 writeln!(cpp_header_file, "\t{}& operator=({}&& o) {{ self = o.self; memset(&o, 0, sizeof({})); return *this; }}", ty, ty, ty).unwrap();
38 writeln!(cpp_header_file, "\tLDK{}* operator &() {{ return &self; }}", ty).unwrap();
39 writeln!(cpp_header_file, "\tLDK{}* operator ->() {{ return &self; }}", ty).unwrap();
40 writeln!(cpp_header_file, "\tconst LDK{}* operator &() const {{ return &self; }}", ty).unwrap();
41 writeln!(cpp_header_file, "\tconst LDK{}* operator ->() const {{ return &self; }}", ty).unwrap();
42 writeln!(cpp_header_file, "}};").unwrap();
45 /// Writes out a C-callable concrete Result<A, B> struct and utility methods
46 pub fn write_result_block<W: std::io::Write>(w: &mut W, mangled_container: &str, ok_type: &str, err_type: &str, clonable: bool) {
47 writeln!(w, "#[repr(C)]").unwrap();
48 writeln!(w, "/// The contents of {}", mangled_container).unwrap();
49 writeln!(w, "pub union {}Ptr {{", mangled_container).unwrap();
51 writeln!(w, "\t/// A pointer to the contents in the success state.").unwrap();
52 writeln!(w, "\t/// Reading from this pointer when `result_ok` is not set is undefined.").unwrap();
53 writeln!(w, "\tpub result: *mut {},", ok_type).unwrap();
55 writeln!(w, "\t/// Note that this value is always NULL, as there are no contents in the OK variant").unwrap();
56 writeln!(w, "\tpub result: *mut std::ffi::c_void,").unwrap();
59 writeln!(w, "\t/// A pointer to the contents in the error state.").unwrap();
60 writeln!(w, "\t/// Reading from this pointer when `result_ok` is set is undefined.").unwrap();
61 writeln!(w, "\tpub err: *mut {},", err_type).unwrap();
63 writeln!(w, "\t/// Note that this value is always NULL, as there are no contents in the Err variant").unwrap();
64 writeln!(w, "\tpub err: *mut std::ffi::c_void,").unwrap();
66 writeln!(w, "}}").unwrap();
67 writeln!(w, "#[repr(C)]").unwrap();
68 writeln!(w, "/// A {} represents the result of a fallible operation,", mangled_container).unwrap();
69 writeln!(w, "/// containing a {} on success and a {} on failure.", ok_type, err_type).unwrap();
70 writeln!(w, "/// `result_ok` indicates the overall state, and the contents are provided via `contents`.").unwrap();
71 writeln!(w, "pub struct {} {{", mangled_container).unwrap();
72 writeln!(w, "\t/// The contents of this {}, accessible via either", mangled_container).unwrap();
73 writeln!(w, "\t/// `err` or `result` depending on the state of `result_ok`.").unwrap();
74 writeln!(w, "\tpub contents: {}Ptr,", mangled_container).unwrap();
75 writeln!(w, "\t/// Whether this {} represents a success state.", mangled_container).unwrap();
76 writeln!(w, "\tpub result_ok: bool,").unwrap();
77 writeln!(w, "}}").unwrap();
79 writeln!(w, "#[no_mangle]").unwrap();
81 writeln!(w, "/// Creates a new {} in the success state.", mangled_container).unwrap();
82 writeln!(w, "pub extern \"C\" fn {}_ok(o: {}) -> {} {{", mangled_container, ok_type, mangled_container).unwrap();
84 writeln!(w, "/// Creates a new {} in the success state.", mangled_container).unwrap();
85 writeln!(w, "pub extern \"C\" fn {}_ok() -> {} {{", mangled_container, mangled_container).unwrap();
87 writeln!(w, "\t{} {{", mangled_container).unwrap();
88 writeln!(w, "\t\tcontents: {}Ptr {{", mangled_container).unwrap();
90 writeln!(w, "\t\t\tresult: Box::into_raw(Box::new(o)),").unwrap();
92 writeln!(w, "\t\t\tresult: std::ptr::null_mut(),").unwrap();
94 writeln!(w, "\t\t}},").unwrap();
95 writeln!(w, "\t\tresult_ok: true,").unwrap();
96 writeln!(w, "\t}}").unwrap();
97 writeln!(w, "}}").unwrap();
99 writeln!(w, "#[no_mangle]").unwrap();
100 if err_type != "()" {
101 writeln!(w, "/// Creates a new {} in the error state.", mangled_container).unwrap();
102 writeln!(w, "pub extern \"C\" fn {}_err(e: {}) -> {} {{", mangled_container, err_type, mangled_container).unwrap();
104 writeln!(w, "/// Creates a new {} in the error state.", mangled_container).unwrap();
105 writeln!(w, "pub extern \"C\" fn {}_err() -> {} {{", mangled_container, mangled_container).unwrap();
107 writeln!(w, "\t{} {{", mangled_container).unwrap();
108 writeln!(w, "\t\tcontents: {}Ptr {{", mangled_container).unwrap();
109 if err_type != "()" {
110 writeln!(w, "\t\t\terr: Box::into_raw(Box::new(e)),").unwrap();
112 writeln!(w, "\t\t\terr: std::ptr::null_mut(),").unwrap();
114 writeln!(w, "\t\t}},").unwrap();
115 writeln!(w, "\t\tresult_ok: false,").unwrap();
116 writeln!(w, "\t}}").unwrap();
117 writeln!(w, "}}").unwrap();
119 writeln!(w, "#[no_mangle]").unwrap();
120 writeln!(w, "/// Frees any resources used by the {}.", mangled_container).unwrap();
121 writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap();
122 writeln!(w, "impl Drop for {} {{", mangled_container).unwrap();
123 writeln!(w, "\tfn drop(&mut self) {{").unwrap();
124 writeln!(w, "\t\tif self.result_ok {{").unwrap();
126 writeln!(w, "\t\t\tif unsafe {{ !(self.contents.result as *mut ()).is_null() }} {{").unwrap();
127 writeln!(w, "\t\t\t\tlet _ = unsafe {{ Box::from_raw(self.contents.result) }};").unwrap();
128 writeln!(w, "\t\t\t}}").unwrap();
130 writeln!(w, "\t\t}} else {{").unwrap();
131 if err_type != "()" {
132 writeln!(w, "\t\t\tif unsafe {{ !(self.contents.err as *mut ()).is_null() }} {{").unwrap();
133 writeln!(w, "\t\t\t\tlet _ = unsafe {{ Box::from_raw(self.contents.err) }};").unwrap();
134 writeln!(w, "\t\t\t}}").unwrap();
136 writeln!(w, "\t\t}}").unwrap();
137 writeln!(w, "\t}}").unwrap();
138 writeln!(w, "}}").unwrap();
140 // TODO: Templates should use () now that they can, too
141 let templ_ok_type = if ok_type != "()" { ok_type } else { "u8" };
142 let templ_err_type = if err_type != "()" { err_type } else { "u8" };
144 writeln!(w, "impl From<crate::c_types::CResultTempl<{}, {}>> for {} {{", templ_ok_type, templ_err_type, mangled_container).unwrap();
145 writeln!(w, "\tfn from(mut o: crate::c_types::CResultTempl<{}, {}>) -> Self {{", templ_ok_type, templ_err_type).unwrap();
146 writeln!(w, "\t\tlet contents = if o.result_ok {{").unwrap();
148 writeln!(w, "\t\t\tlet result = unsafe {{ o.contents.result }};").unwrap();
149 writeln!(w, "\t\t\tunsafe {{ o.contents.result = std::ptr::null_mut() }};").unwrap();
150 writeln!(w, "\t\t\t{}Ptr {{ result }}", mangled_container).unwrap();
152 writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(o.contents.result) }};").unwrap();
153 writeln!(w, "\t\t\to.contents.result = std::ptr::null_mut();").unwrap();
154 writeln!(w, "\t\t\t{}Ptr {{ result: std::ptr::null_mut() }}", mangled_container).unwrap();
156 writeln!(w, "\t\t}} else {{").unwrap();
157 if err_type != "()" {
158 writeln!(w, "\t\t\tlet err = unsafe {{ o.contents.err }};").unwrap();
159 writeln!(w, "\t\t\tunsafe {{ o.contents.err = std::ptr::null_mut(); }}").unwrap();
160 writeln!(w, "\t\t\t{}Ptr {{ err }}", mangled_container).unwrap();
162 writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(o.contents.err) }};").unwrap();
163 writeln!(w, "\t\t\to.contents.err = std::ptr::null_mut();").unwrap();
164 writeln!(w, "\t\t\t{}Ptr {{ err: std::ptr::null_mut() }}", mangled_container).unwrap();
166 writeln!(w, "\t\t}};").unwrap();
167 writeln!(w, "\t\tSelf {{").unwrap();
168 writeln!(w, "\t\t\tcontents,").unwrap();
169 writeln!(w, "\t\t\tresult_ok: o.result_ok,").unwrap();
170 writeln!(w, "\t\t}}").unwrap();
171 writeln!(w, "\t}}").unwrap();
172 writeln!(w, "}}").unwrap();
175 writeln!(w, "impl Clone for {} {{", mangled_container).unwrap();
176 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
177 writeln!(w, "\t\tif self.result_ok {{").unwrap();
178 writeln!(w, "\t\t\tSelf {{ result_ok: true, contents: {}Ptr {{", mangled_container).unwrap();
180 writeln!(w, "\t\t\t\tresult: Box::into_raw(Box::new(<{}>::clone(unsafe {{ &*self.contents.result }})))", ok_type).unwrap();
182 writeln!(w, "\t\t\t\tresult: std::ptr::null_mut()").unwrap();
184 writeln!(w, "\t\t\t}} }}").unwrap();
185 writeln!(w, "\t\t}} else {{").unwrap();
186 writeln!(w, "\t\t\tSelf {{ result_ok: false, contents: {}Ptr {{", mangled_container).unwrap();
187 if err_type != "()" {
188 writeln!(w, "\t\t\t\terr: Box::into_raw(Box::new(<{}>::clone(unsafe {{ &*self.contents.err }})))", err_type).unwrap();
190 writeln!(w, "\t\t\t\terr: std::ptr::null_mut()").unwrap();
192 writeln!(w, "\t\t\t}} }}").unwrap();
193 writeln!(w, "\t\t}}").unwrap();
194 writeln!(w, "\t}}").unwrap();
195 writeln!(w, "}}").unwrap();
196 writeln!(w, "#[no_mangle]").unwrap();
197 writeln!(w, "/// Creates a new {} which has the same data as `orig`", mangled_container).unwrap();
198 writeln!(w, "/// but with all dynamically-allocated buffers duplicated in new buffers.").unwrap();
199 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{ orig.clone() }}", mangled_container, mangled_container, mangled_container).unwrap();
203 /// Writes out a C-callable concrete Vec<A> struct and utility methods
204 pub fn write_vec_block<W: std::io::Write>(w: &mut W, mangled_container: &str, inner_type: &str, clonable: bool) {
205 writeln!(w, "#[repr(C)]").unwrap();
206 writeln!(w, "/// A dynamically-allocated array of {}s of arbitrary size.", inner_type).unwrap();
207 writeln!(w, "/// This corresponds to std::vector in C++").unwrap();
208 writeln!(w, "pub struct {} {{", mangled_container).unwrap();
209 writeln!(w, "\t/// The elements in the array.").unwrap();
210 writeln!(w, "\t/// If datalen is non-0 this must be a valid, non-NULL pointer allocated by malloc().").unwrap();
211 writeln!(w, "\tpub data: *mut {},", inner_type).unwrap();
212 writeln!(w, "\t/// The number of elements pointed to by `data`.").unwrap();
213 writeln!(w, "\tpub datalen: usize").unwrap();
214 writeln!(w, "}}").unwrap();
216 writeln!(w, "impl {} {{", mangled_container).unwrap();
217 writeln!(w, "\t#[allow(unused)] pub(crate) fn into_rust(&mut self) -> Vec<{}> {{", inner_type).unwrap();
218 writeln!(w, "\t\tif self.datalen == 0 {{ return Vec::new(); }}").unwrap();
219 writeln!(w, "\t\tlet ret = unsafe {{ Box::from_raw(std::slice::from_raw_parts_mut(self.data, self.datalen)) }}.into();").unwrap();
220 writeln!(w, "\t\tself.data = std::ptr::null_mut();").unwrap();
221 writeln!(w, "\t\tself.datalen = 0;").unwrap();
222 writeln!(w, "\t\tret").unwrap();
223 writeln!(w, "\t}}").unwrap();
224 writeln!(w, "\t#[allow(unused)] pub(crate) fn as_slice(&self) -> &[{}] {{", inner_type).unwrap();
225 writeln!(w, "\t\tunsafe {{ std::slice::from_raw_parts_mut(self.data, self.datalen) }}").unwrap();
226 writeln!(w, "\t}}").unwrap();
227 writeln!(w, "}}").unwrap();
229 writeln!(w, "impl From<Vec<{}>> for {} {{", inner_type, mangled_container).unwrap();
230 writeln!(w, "\tfn from(v: Vec<{}>) -> Self {{", inner_type).unwrap();
231 writeln!(w, "\t\tlet datalen = v.len();").unwrap();
232 writeln!(w, "\t\tlet data = Box::into_raw(v.into_boxed_slice());").unwrap();
233 writeln!(w, "\t\tSelf {{ datalen, data: unsafe {{ (*data).as_mut_ptr() }} }}").unwrap();
234 writeln!(w, "\t}}").unwrap();
235 writeln!(w, "}}").unwrap();
237 writeln!(w, "#[no_mangle]").unwrap();
238 writeln!(w, "/// Frees the buffer pointed to by `data` if `datalen` is non-0.").unwrap();
239 writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap();
240 writeln!(w, "impl Drop for {} {{", mangled_container).unwrap();
241 writeln!(w, "\tfn drop(&mut self) {{").unwrap();
242 writeln!(w, "\t\tif self.datalen == 0 {{ return; }}").unwrap();
243 writeln!(w, "\t\tunsafe {{ Box::from_raw(std::slice::from_raw_parts_mut(self.data, self.datalen)) }};").unwrap();
244 writeln!(w, "\t}}").unwrap();
245 writeln!(w, "}}").unwrap();
247 writeln!(w, "impl Clone for {} {{", mangled_container).unwrap();
248 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
249 writeln!(w, "\t\tlet mut res = Vec::new();").unwrap();
250 writeln!(w, "\t\tif self.datalen == 0 {{ return Self::from(res); }}").unwrap();
251 writeln!(w, "\t\tres.extend_from_slice(unsafe {{ std::slice::from_raw_parts_mut(self.data, self.datalen) }});").unwrap();
252 writeln!(w, "\t\tSelf::from(res)").unwrap();
253 writeln!(w, "\t}}").unwrap();
254 writeln!(w, "}}").unwrap();
258 /// Writes out a C-callable concrete (A, B, ...) struct and utility methods
259 pub fn write_tuple_block<W: std::io::Write>(w: &mut W, mangled_container: &str, types: &[String], clonable: bool) {
260 writeln!(w, "#[repr(C)]").unwrap();
261 writeln!(w, "/// A tuple of {} elements. See the individual fields for the types contained.", types.len()).unwrap();
262 writeln!(w, "pub struct {} {{", mangled_container).unwrap();
263 for (idx, ty) in types.iter().enumerate() {
264 writeln!(w, "\t/// The element at position {}", idx).unwrap();
265 writeln!(w, "\tpub {}: {},", ('a' as u8 + idx as u8) as char, ty).unwrap();
267 writeln!(w, "}}").unwrap();
269 let mut tuple_str = "(".to_owned();
270 for (idx, ty) in types.iter().enumerate() {
271 if idx != 0 { tuple_str += ", "; }
276 writeln!(w, "impl From<{}> for {} {{", tuple_str, mangled_container).unwrap();
277 writeln!(w, "\tfn from (tup: {}) -> Self {{", tuple_str).unwrap();
278 writeln!(w, "\t\tSelf {{").unwrap();
279 for idx in 0..types.len() {
280 writeln!(w, "\t\t\t{}: tup.{},", ('a' as u8 + idx as u8) as char, idx).unwrap();
282 writeln!(w, "\t\t}}").unwrap();
283 writeln!(w, "\t}}").unwrap();
284 writeln!(w, "}}").unwrap();
285 writeln!(w, "impl {} {{", mangled_container).unwrap();
286 writeln!(w, "\t#[allow(unused)] pub(crate) fn to_rust(mut self) -> {} {{", tuple_str).unwrap();
287 write!(w, "\t\t(").unwrap();
288 for idx in 0..types.len() {
289 write!(w, "{}self.{}", if idx != 0 {", "} else {""}, ('a' as u8 + idx as u8) as char).unwrap();
291 writeln!(w, ")").unwrap();
292 writeln!(w, "\t}}").unwrap();
293 writeln!(w, "}}").unwrap();
296 writeln!(w, "impl Clone for {} {{", mangled_container).unwrap();
297 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
298 writeln!(w, "\t\tSelf {{").unwrap();
299 for idx in 0..types.len() {
300 writeln!(w, "\t\t\t{}: self.{}.clone(),", ('a' as u8 + idx as u8) as char, ('a' as u8 + idx as u8) as char).unwrap();
302 writeln!(w, "\t\t}}").unwrap();
303 writeln!(w, "\t}}").unwrap();
304 writeln!(w, "}}").unwrap();
305 writeln!(w, "#[no_mangle]").unwrap();
306 writeln!(w, "/// Creates a new tuple which has the same data as `orig`").unwrap();
307 writeln!(w, "/// but with all dynamically-allocated buffers duplicated in new buffers.").unwrap();
308 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{ orig.clone() }}", mangled_container, mangled_container, mangled_container).unwrap();
311 writeln!(w, "/// Creates a new {} from the contained elements.", mangled_container).unwrap();
312 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_new(", mangled_container).unwrap();
313 for (idx, gen) in types.iter().enumerate() {
314 write!(w, "{}{}: ", if idx != 0 { ", " } else { "" }, ('a' as u8 + idx as u8) as char).unwrap();
315 //if !self.write_c_type_intern(&mut created_container, gen, generics, false, false, false) { return false; }
316 write!(w, "{}", gen).unwrap();
318 writeln!(w, ") -> {} {{", mangled_container).unwrap();
319 write!(w, "\t{} {{ ", mangled_container).unwrap();
320 for idx in 0..types.len() {
321 write!(w, "{}, ", ('a' as u8 + idx as u8) as char).unwrap();
323 writeln!(w, "}}\n}}\n").unwrap();
325 writeln!(w, "#[no_mangle]").unwrap();
326 writeln!(w, "/// Frees any resources used by the {}.", mangled_container).unwrap();
327 writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap();
330 /// Writes out a C-callable concrete Option<A> struct and utility methods
331 pub fn write_option_block<W: std::io::Write>(w: &mut W, mangled_container: &str, inner_type: &str, clonable: bool) {
332 writeln!(w, "#[repr(C)]").unwrap();
334 writeln!(w, "#[derive(Clone)]").unwrap();
336 writeln!(w, "/// An enum which can either contain a {} or not", inner_type).unwrap();
337 writeln!(w, "pub enum {} {{", mangled_container).unwrap();
338 writeln!(w, "\t/// When we're in this state, this {} contains a {}", mangled_container, inner_type).unwrap();
339 writeln!(w, "\tSome({}),", inner_type).unwrap();
340 writeln!(w, "\t/// When we're in this state, this {} contains nothing", mangled_container).unwrap();
341 writeln!(w, "\tNone").unwrap();
342 writeln!(w, "}}").unwrap();
344 writeln!(w, "impl {} {{", mangled_container).unwrap();
345 writeln!(w, "\t#[allow(unused)] pub(crate) fn is_some(&self) -> bool {{").unwrap();
346 writeln!(w, "\t\tif let Self::Some(_) = self {{ true }} else {{ false }}").unwrap();
347 writeln!(w, "\t}}").unwrap();
348 writeln!(w, "\t#[allow(unused)] pub(crate) fn take(mut self) -> {} {{", inner_type).unwrap();
349 writeln!(w, "\t\tif let Self::Some(v) = self {{ v }} else {{ unreachable!() }}").unwrap();
350 writeln!(w, "\t}}").unwrap();
351 writeln!(w, "}}").unwrap();
353 writeln!(w, "#[no_mangle]").unwrap();
354 writeln!(w, "/// Constructs a new {} containing a {}", mangled_container, inner_type).unwrap();
355 writeln!(w, "pub extern \"C\" fn {}_some(o: {}) -> {} {{", mangled_container, inner_type, mangled_container).unwrap();
356 writeln!(w, "\t{}::Some(o)", mangled_container).unwrap();
357 writeln!(w, "}}").unwrap();
359 writeln!(w, "#[no_mangle]").unwrap();
360 writeln!(w, "/// Constructs a new {} containing nothing", mangled_container).unwrap();
361 writeln!(w, "pub extern \"C\" fn {}_none() -> {} {{", mangled_container, mangled_container).unwrap();
362 writeln!(w, "\t{}::None", mangled_container).unwrap();
363 writeln!(w, "}}").unwrap();
365 writeln!(w, "#[no_mangle]").unwrap();
366 writeln!(w, "/// Frees any resources associated with the {}, if we are in the Some state", inner_type).unwrap();
367 writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap();
369 writeln!(w, "#[no_mangle]").unwrap();
370 writeln!(w, "/// Creates a new {} which has the same data as `orig`", mangled_container).unwrap();
371 writeln!(w, "/// but with all dynamically-allocated buffers duplicated in new buffers.").unwrap();
372 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{ orig.clone() }}", mangled_container, mangled_container, mangled_container).unwrap();
376 /// Prints the docs from a given attribute list unless its tagged no export
377 pub fn writeln_docs<W: std::io::Write>(w: &mut W, attrs: &[syn::Attribute], prefix: &str) {
378 for attr in attrs.iter() {
379 let tokens_clone = attr.tokens.clone();
380 let mut token_iter = tokens_clone.into_iter();
381 if let Some(token) = token_iter.next() {
383 TokenTree::Punct(c) if c.as_char() == '=' => {
384 // syn gets '=' from '///' or '//!' as it is syntax for #[doc = ""]
386 TokenTree::Group(_) => continue, // eg #[derive()]
387 _ => unimplemented!(),
391 syn::AttrStyle::Inner(_) => {
392 match token_iter.next().unwrap() {
393 TokenTree::Literal(lit) => {
394 // Drop the first and last chars from lit as they are always "
395 let doc = format!("{}", lit);
396 writeln!(w, "{}//!{}", prefix, &doc[1..doc.len() - 1]).unwrap();
398 _ => unimplemented!(),
401 syn::AttrStyle::Outer => {
402 match token_iter.next().unwrap() {
403 TokenTree::Literal(lit) => {
404 // Drop the first and last chars from lit as they are always "
405 let doc = format!("{}", lit);
406 writeln!(w, "{}///{}", prefix, &doc[1..doc.len() - 1]).unwrap();
408 _ => unimplemented!(),
415 /// Print the parameters in a method declaration, starting after the open parenthesis, through and
416 /// including the closing parenthesis and return value, but not including the open bracket or any
417 /// trailing semicolons.
419 /// Usable both for a function definition and declaration.
421 /// this_param is used when returning Self or accepting a self parameter, and should be the
422 /// concrete, mapped type.
423 pub fn write_method_params<W: std::io::Write>(w: &mut W, sig: &syn::Signature, this_param: &str, types: &mut TypeResolver, generics: Option<&GenericTypes>, self_ptr: bool, fn_decl: bool) {
424 if sig.constness.is_some() || sig.asyncness.is_some() || sig.unsafety.is_some() ||
425 sig.abi.is_some() || sig.variadic.is_some() {
428 if sig.generics.lt_token.is_some() {
429 for generic in sig.generics.params.iter() {
431 syn::GenericParam::Type(_)|syn::GenericParam::Lifetime(_) => {
432 // We ignore these, if they're not on skipped args, we'll blow up
433 // later, and lifetimes we just hope the C client enforces.
435 _ => unimplemented!(),
440 let mut first_arg = true;
441 let mut num_unused = 0;
442 for inp in sig.inputs.iter() {
444 syn::FnArg::Receiver(recv) => {
445 if !recv.attrs.is_empty() { unimplemented!(); }
446 write!(w, "{}this_arg: {}{}", if recv.reference.is_none() { "mut " } else { "" },
447 if recv.reference.is_some() {
448 match (self_ptr, recv.mutability.is_some()) {
449 (true, true) => "*mut ",
450 (true, false) => "*const ",
451 (false, true) => "&mut ",
452 (false, false) => "&",
454 } else { "" }, this_param).unwrap();
458 syn::FnArg::Typed(arg) => {
459 if types.skip_arg(&*arg.ty, generics) { continue; }
460 if !arg.attrs.is_empty() { unimplemented!(); }
461 // First get the c type so that we can check if it ends up being a reference:
462 let mut c_type = Vec::new();
463 types.write_c_type(&mut c_type, &*arg.ty, generics, false);
465 syn::Pat::Ident(ident) => {
466 if !ident.attrs.is_empty() || ident.subpat.is_some() {
469 write!(w, "{}{}{}: ", if first_arg { "" } else { ", " }, if !fn_decl || c_type[0] == '&' as u8 || c_type[0] == '*' as u8 { "" } else { "mut " }, ident.ident).unwrap();
472 syn::Pat::Wild(wild) => {
473 if !wild.attrs.is_empty() { unimplemented!(); }
474 write!(w, "{}unused_{}: ", if first_arg { "" } else { ", " }, num_unused).unwrap();
477 _ => unimplemented!(),
479 w.write(&c_type).unwrap();
483 write!(w, ")").unwrap();
485 syn::ReturnType::Type(_, rtype) => {
486 write!(w, " -> ").unwrap();
487 if let Some(mut remaining_path) = first_seg_self(&*rtype) {
488 if remaining_path.next().is_none() {
489 write!(w, "{}", this_param).unwrap();
493 types.write_c_type(w, &*rtype, generics, true);
499 /// Print the main part of a method declaration body, starting with a newline after the function
500 /// open bracket and converting each function parameter to or from C-mapped types. Ends with "let
501 /// mut ret = " assuming the next print will be the unmapped Rust function to call followed by the
502 /// parameters we mapped to/from C here.
503 pub fn write_method_var_decl_body<W: std::io::Write>(w: &mut W, sig: &syn::Signature, extra_indent: &str, types: &TypeResolver, generics: Option<&GenericTypes>, to_c: bool) {
504 let mut num_unused = 0u32;
505 for inp in sig.inputs.iter() {
507 syn::FnArg::Receiver(_) => {},
508 syn::FnArg::Typed(arg) => {
509 if types.skip_arg(&*arg.ty, generics) { continue; }
510 if !arg.attrs.is_empty() { unimplemented!(); }
511 macro_rules! write_new_var {
512 ($ident: expr, $ty: expr) => {
514 if types.write_to_c_conversion_new_var(w, &$ident, &$ty, generics, false) {
515 write!(w, "\n\t{}", extra_indent).unwrap();
518 if types.write_from_c_conversion_new_var(w, &$ident, &$ty, generics) {
519 write!(w, "\n\t{}", extra_indent).unwrap();
525 syn::Pat::Ident(ident) => {
526 if !ident.attrs.is_empty() || ident.subpat.is_some() {
529 write_new_var!(ident.ident, *arg.ty);
531 syn::Pat::Wild(w) => {
532 if !w.attrs.is_empty() { unimplemented!(); }
533 write_new_var!(format_ident!("unused_{}", num_unused), *arg.ty);
536 _ => unimplemented!(),
542 syn::ReturnType::Type(_, _) => {
543 write!(w, "let mut ret = ").unwrap();
549 /// Prints the parameters in a method call, starting after the open parenthesis and ending with a
550 /// final return statement returning the method's result. Should be followed by a single closing
553 /// The return value is expected to be bound to a variable named `ret` which is available after a
554 /// method-call-ending semicolon.
555 pub fn write_method_call_params<W: std::io::Write>(w: &mut W, sig: &syn::Signature, extra_indent: &str, types: &TypeResolver, generics: Option<&GenericTypes>, this_type: &str, to_c: bool) {
556 let mut first_arg = true;
557 let mut num_unused = 0;
558 for inp in sig.inputs.iter() {
560 syn::FnArg::Receiver(recv) => {
561 if !recv.attrs.is_empty() { unimplemented!(); }
563 if recv.reference.is_none() { unimplemented!(); }
564 write!(w, "self.this_arg").unwrap();
568 syn::FnArg::Typed(arg) => {
569 if types.skip_arg(&*arg.ty, generics) {
572 write!(w, ", ").unwrap();
575 types.no_arg_to_rust(w, &*arg.ty, generics);
579 if !arg.attrs.is_empty() { unimplemented!(); }
580 macro_rules! write_ident {
583 write!(w, ", ").unwrap();
587 types.write_to_c_conversion_inline_prefix(w, &*arg.ty, generics, false);
588 write!(w, "{}", $ident).unwrap();
589 types.write_to_c_conversion_inline_suffix(w, &*arg.ty, generics, false);
591 types.write_from_c_conversion_prefix(w, &*arg.ty, generics);
592 write!(w, "{}", $ident).unwrap();
593 types.write_from_c_conversion_suffix(w, &*arg.ty, generics);
598 syn::Pat::Ident(ident) => {
599 if !ident.attrs.is_empty() || ident.subpat.is_some() {
602 write_ident!(ident.ident);
604 syn::Pat::Wild(w) => {
605 if !w.attrs.is_empty() { unimplemented!(); }
606 write_ident!(format!("unused_{}", num_unused));
609 _ => unimplemented!(),
614 write!(w, ")").unwrap();
616 syn::ReturnType::Type(_, rtype) => {
617 write!(w, ";\n\t{}", extra_indent).unwrap();
619 let self_segs_iter = first_seg_self(&*rtype);
620 if to_c && first_seg_self(&*rtype).is_some() {
621 // Assume rather blindly that we're returning an associated trait from a C fn call to a Rust trait object.
622 write!(w, "ret").unwrap();
623 } else if !to_c && self_segs_iter.is_some() && self_segs_iter.unwrap().next().is_none() {
624 // If we're returning "Self" (and not "Self::X"), just do it manually
625 write!(w, "{} {{ inner: Box::into_raw(Box::new(ret)), is_owned: true }}", this_type).unwrap();
627 let new_var = types.write_from_c_conversion_new_var(w, &format_ident!("ret"), rtype, generics);
629 write!(w, "\n\t{}", extra_indent).unwrap();
631 types.write_from_c_conversion_prefix(w, &*rtype, generics);
632 write!(w, "ret").unwrap();
633 types.write_from_c_conversion_suffix(w, &*rtype, generics);
635 let new_var = types.write_to_c_conversion_new_var(w, &format_ident!("ret"), &rtype, generics, true);
637 write!(w, "\n\t{}", extra_indent).unwrap();
639 types.write_to_c_conversion_inline_prefix(w, &rtype, generics, true);
640 write!(w, "ret").unwrap();
641 types.write_to_c_conversion_inline_suffix(w, &rtype, generics, true);
648 /// Prints concrete generic parameters for a struct/trait/function, including the less-than and
649 /// greater-than symbols, if any generic parameters are defined.
650 pub fn maybe_write_generics<W: std::io::Write>(w: &mut W, generics: &syn::Generics, types: &TypeResolver, concrete_lifetimes: bool) {
651 let mut gen_types = GenericTypes::new();
652 assert!(gen_types.learn_generics(generics, types));
653 if !generics.params.is_empty() {
654 write!(w, "<").unwrap();
655 for (idx, generic) in generics.params.iter().enumerate() {
657 syn::GenericParam::Type(type_param) => {
658 let mut printed_param = false;
659 for bound in type_param.bounds.iter() {
660 if let syn::TypeParamBound::Trait(trait_bound) = bound {
661 assert_simple_bound(&trait_bound);
662 write!(w, "{}{}", if idx != 0 { ", " } else { "" }, gen_types.maybe_resolve_ident(&type_param.ident).unwrap()).unwrap();
664 unimplemented!("Can't print generic params that have multiple non-lifetime bounds");
666 printed_param = true;
670 syn::GenericParam::Lifetime(lt) => {
671 if concrete_lifetimes {
672 write!(w, "'static").unwrap();
674 write!(w, "{}'{}", if idx != 0 { ", " } else { "" }, lt.lifetime.ident).unwrap();
677 _ => unimplemented!(),
680 write!(w, ">").unwrap();