--- /dev/null
+//! Printing logic for basic blocks of Rust-mapped code - parts of functions and declarations but
+//! not the full mapping logic.
+
+use std::collections::HashMap;
+use std::fs::File;
+use std::io::Write;
+use proc_macro2::{TokenTree, Span};
+
+use crate::types::*;
+
+/// Writes out a C++ wrapper class for the given type, which contains various utilities to access
+/// the underlying C-mapped type safely avoiding some common memory management issues by handling
+/// resource-freeing and prevending accidental raw copies.
+pub fn write_cpp_wrapper(cpp_header_file: &mut File, ty: &str, has_destructor: bool) {
+ writeln!(cpp_header_file, "class {} {{", ty).unwrap();
+ writeln!(cpp_header_file, "private:").unwrap();
+ writeln!(cpp_header_file, "\tLDK{} self;", ty).unwrap();
+ writeln!(cpp_header_file, "public:").unwrap();
+ writeln!(cpp_header_file, "\t{}(const {}&) = delete;", ty, ty).unwrap();
+ if has_destructor {
+ writeln!(cpp_header_file, "\t~{}() {{ {}_free(self); }}", ty, ty).unwrap();
+ }
+ writeln!(cpp_header_file, "\t{}({}&& o) : self(o.self) {{ memset(&o, 0, sizeof({})); }}", ty, ty, ty).unwrap();
+ writeln!(cpp_header_file, "\t{}(LDK{}&& m_self) : self(m_self) {{ memset(&m_self, 0, sizeof(LDK{})); }}", ty, ty, ty).unwrap();
+ writeln!(cpp_header_file, "\toperator LDK{}() {{ LDK{} res = self; memset(&self, 0, sizeof(LDK{})); return res; }}", ty, ty, ty).unwrap();
+ writeln!(cpp_header_file, "\tLDK{}* operator &() {{ return &self; }}", ty).unwrap();
+ writeln!(cpp_header_file, "\tLDK{}* operator ->() {{ return &self; }}", ty).unwrap();
+ writeln!(cpp_header_file, "\tconst LDK{}* operator &() const {{ return &self; }}", ty).unwrap();
+ writeln!(cpp_header_file, "\tconst LDK{}* operator ->() const {{ return &self; }}", ty).unwrap();
+ writeln!(cpp_header_file, "}};").unwrap();
+}
+
+/// Prints the docs from a given attribute list unless its tagged no export
+pub fn writeln_docs<W: std::io::Write>(w: &mut W, attrs: &[syn::Attribute], prefix: &str) {
+ for attr in attrs.iter() {
+ let tokens_clone = attr.tokens.clone();
+ let mut token_iter = tokens_clone.into_iter();
+ if let Some(token) = token_iter.next() {
+ match token {
+ TokenTree::Punct(c) if c.as_char() == '=' => {
+ // syn gets '=' from '///' or '//!' as it is syntax for #[doc = ""]
+ },
+ TokenTree::Group(_) => continue, // eg #[derive()]
+ _ => unimplemented!(),
+ }
+ } else { continue; }
+ match attr.style {
+ syn::AttrStyle::Inner(_) => {
+ match token_iter.next().unwrap() {
+ TokenTree::Literal(lit) => {
+ // Drop the first and last chars from lit as they are always "
+ let doc = format!("{}", lit);
+ writeln!(w, "{}//!{}", prefix, &doc[1..doc.len() - 1]).unwrap();
+ },
+ _ => unimplemented!(),
+ }
+ },
+ syn::AttrStyle::Outer => {
+ match token_iter.next().unwrap() {
+ TokenTree::Literal(lit) => {
+ // Drop the first and last chars from lit as they are always "
+ let doc = format!("{}", lit);
+ writeln!(w, "{}///{}", prefix, &doc[1..doc.len() - 1]).unwrap();
+ },
+ _ => unimplemented!(),
+ }
+ },
+ }
+ }
+}
+
+/// Print the parameters in a method declaration, starting after the open parenthesis, through and
+/// including the closing parenthesis and return value, but not including the open bracket or any
+/// trailing semicolons.
+///
+/// Usable both for a function definition and declaration.
+///
+/// this_param is used when returning Self or accepting a self parameter, and should be the
+/// concrete, mapped type.
+pub fn write_method_params<W: std::io::Write>(w: &mut W, sig: &syn::Signature, associated_types: &HashMap<&syn::Ident, &syn::Ident>, this_param: &str, types: &mut TypeResolver, generics: Option<&GenericTypes>, self_ptr: bool, fn_decl: bool) {
+ if sig.constness.is_some() || sig.asyncness.is_some() || sig.unsafety.is_some() ||
+ sig.abi.is_some() || sig.variadic.is_some() {
+ unimplemented!();
+ }
+ if sig.generics.lt_token.is_some() {
+ for generic in sig.generics.params.iter() {
+ match generic {
+ syn::GenericParam::Type(_)|syn::GenericParam::Lifetime(_) => {
+ // We ignore these, if they're not on skipped args, we'll blow up
+ // later, and lifetimes we just hope the C client enforces.
+ },
+ _ => unimplemented!(),
+ }
+ }
+ }
+
+ let mut first_arg = true;
+ let mut num_unused = 0;
+ for inp in sig.inputs.iter() {
+ match inp {
+ syn::FnArg::Receiver(recv) => {
+ if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); }
+ write!(w, "this_arg: {}{}",
+ match (self_ptr, recv.mutability.is_some()) {
+ (true, true) => "*mut ",
+ (true, false) => "*const ",
+ (false, true) => "&mut ",
+ (false, false) => "&",
+ }, this_param).unwrap();
+ assert!(first_arg);
+ first_arg = false;
+ },
+ syn::FnArg::Typed(arg) => {
+ if types.skip_arg(&*arg.ty, generics) { continue; }
+ if !arg.attrs.is_empty() { unimplemented!(); }
+ let mut is_ref = if let syn::Type::Reference(_) = *arg.ty { true } else { false };
+ if let syn::Type::Reference(syn::TypeReference { ref elem, .. }) = *arg.ty {
+ if let syn::Type::Slice(_) = &**elem {
+ // Slices are mapped to non-ref Vec types, so we want them to be mut
+ // letting us drain(..) the underlying Vec.
+ is_ref = false;
+ }
+ }
+ match &*arg.pat {
+ syn::Pat::Ident(ident) => {
+ if !ident.attrs.is_empty() || ident.subpat.is_some() {
+ unimplemented!();
+ }
+ write!(w, "{}{}{}: ", if first_arg { "" } else { ", " }, if is_ref || !fn_decl { "" } else { "mut " }, ident.ident).unwrap();
+ first_arg = false;
+ },
+ syn::Pat::Wild(wild) => {
+ if !wild.attrs.is_empty() { unimplemented!(); }
+ write!(w, "{}unused_{}: ", if first_arg { "" } else { ", " }, num_unused).unwrap();
+ num_unused += 1;
+ },
+ _ => unimplemented!(),
+ }
+ types.write_c_type(w, &*arg.ty, generics, false);
+ }
+ }
+ }
+ write!(w, ")").unwrap();
+ match &sig.output {
+ syn::ReturnType::Type(_, rtype) => {
+ write!(w, " -> ").unwrap();
+ if let Some(mut remaining_path) = first_seg_self(&*rtype) {
+ if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) {
+ // We're returning an associated type in a trait impl. Its probably a safe bet
+ // that its also a trait, so just return the trait type.
+ let real_type = associated_types.get(associated_seg).unwrap();
+ types.write_c_type(w, &syn::Type::Path(syn::TypePath { qself: None,
+ path: syn::PathSegment {
+ ident: (*real_type).clone(),
+ arguments: syn::PathArguments::None
+ }.into()
+ }), generics, true);
+ } else {
+ write!(w, "{}", this_param).unwrap();
+ }
+ } else {
+ if let syn::Type::Reference(r) = &**rtype {
+ // We can't return a reference, cause we allocate things on the stack.
+ types.write_c_type(w, &*r.elem, generics, true);
+ } else {
+ types.write_c_type(w, &*rtype, generics, true);
+ }
+ }
+ },
+ _ => {},
+ }
+}
+
+/// Print the main part of a method declaration body, starting with a newline after the function
+/// open bracket and converting each function parameter to or from C-mapped types. Ends with "let
+/// mut ret = " assuming the next print will be the unmapped Rust function to call followed by the
+/// parameters we mapped to/from C here.
+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) {
+ let mut num_unused = 0;
+ for inp in sig.inputs.iter() {
+ match inp {
+ syn::FnArg::Receiver(_) => {},
+ syn::FnArg::Typed(arg) => {
+ if types.skip_arg(&*arg.ty, generics) { continue; }
+ if !arg.attrs.is_empty() { unimplemented!(); }
+ macro_rules! write_new_var {
+ ($ident: expr, $ty: expr) => {
+ if to_c {
+ if types.write_to_c_conversion_new_var(w, &$ident, &$ty, generics, false) {
+ write!(w, "\n\t{}", extra_indent).unwrap();
+ }
+ } else {
+ if types.write_from_c_conversion_new_var(w, &$ident, &$ty, generics) {
+ write!(w, "\n\t{}", extra_indent).unwrap();
+ }
+ }
+ }
+ }
+ match &*arg.pat {
+ syn::Pat::Ident(ident) => {
+ if !ident.attrs.is_empty() || ident.subpat.is_some() {
+ unimplemented!();
+ }
+ write_new_var!(ident.ident, *arg.ty);
+ },
+ syn::Pat::Wild(w) => {
+ if !w.attrs.is_empty() { unimplemented!(); }
+ write_new_var!(syn::Ident::new(&format!("unused_{}", num_unused), Span::call_site()), *arg.ty);
+ num_unused += 1;
+ },
+ _ => unimplemented!(),
+ }
+ }
+ }
+ }
+ match &sig.output {
+ syn::ReturnType::Type(_, _) => {
+ write!(w, "let mut ret = ").unwrap();
+ },
+ _ => {},
+ }
+}
+
+/// Prints the parameters in a method call, starting after the open parenthesis and ending with a
+/// final return statement returning the method's result. Should be followed by a single closing
+/// bracket.
+///
+/// The return value is expected to be bound to a variable named `ret` which is available after a
+/// method-call-ending semicolon.
+pub fn write_method_call_params<W: std::io::Write>(w: &mut W, sig: &syn::Signature, associated_types: &HashMap<&syn::Ident, &syn::Ident>, extra_indent: &str, types: &TypeResolver, generics: Option<&GenericTypes>, this_type: &str, to_c: bool) {
+ let mut first_arg = true;
+ let mut num_unused = 0;
+ for inp in sig.inputs.iter() {
+ match inp {
+ syn::FnArg::Receiver(recv) => {
+ if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); }
+ if to_c {
+ write!(w, "self.this_arg").unwrap();
+ first_arg = false;
+ }
+ },
+ syn::FnArg::Typed(arg) => {
+ if types.skip_arg(&*arg.ty, generics) {
+ if !to_c {
+ if !first_arg {
+ write!(w, ", ").unwrap();
+ }
+ first_arg = false;
+ types.no_arg_to_rust(w, &*arg.ty, generics);
+ }
+ continue;
+ }
+ if !arg.attrs.is_empty() { unimplemented!(); }
+ macro_rules! write_ident {
+ ($ident: expr) => {
+ if !first_arg {
+ write!(w, ", ").unwrap();
+ }
+ first_arg = false;
+ if to_c {
+ types.write_to_c_conversion_inline_prefix(w, &*arg.ty, generics, false);
+ write!(w, "{}", $ident).unwrap();
+ types.write_to_c_conversion_inline_suffix(w, &*arg.ty, generics, false);
+ } else {
+ types.write_from_c_conversion_prefix(w, &*arg.ty, generics);
+ write!(w, "{}", $ident).unwrap();
+ types.write_from_c_conversion_suffix(w, &*arg.ty, generics);
+ }
+ }
+ }
+ match &*arg.pat {
+ syn::Pat::Ident(ident) => {
+ if !ident.attrs.is_empty() || ident.subpat.is_some() {
+ unimplemented!();
+ }
+ write_ident!(ident.ident);
+ },
+ syn::Pat::Wild(w) => {
+ if !w.attrs.is_empty() { unimplemented!(); }
+ write_ident!(format!("unused_{}", num_unused));
+ num_unused += 1;
+ },
+ _ => unimplemented!(),
+ }
+ }
+ }
+ }
+ write!(w, ")").unwrap();
+ match &sig.output {
+ syn::ReturnType::Type(_, rtype) => {
+ write!(w, ";\n\t{}", extra_indent).unwrap();
+
+ if to_c && first_seg_self(&*rtype).is_some() {
+ // Assume rather blindly that we're returning an associated trait from a C fn call to a Rust trait object.
+ write!(w, "ret").unwrap();
+ } else if !to_c && first_seg_self(&*rtype).is_some() {
+ if let Some(mut remaining_path) = first_seg_self(&*rtype) {
+ if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) {
+ let real_type = associated_types.get(associated_seg).unwrap();
+ if let Some(t) = types.crate_types.traits.get(&types.maybe_resolve_ident(&real_type).unwrap()) {
+ // We're returning an associated trait from a Rust fn call to a C trait
+ // object.
+ writeln!(w, "let mut rust_obj = {} {{ inner: Box::into_raw(Box::new(ret)), is_owned: true }};", this_type).unwrap();
+ writeln!(w, "\t{}let mut ret = {}_as_{}(&rust_obj);", extra_indent, this_type, t.ident).unwrap();
+ writeln!(w, "\t{}// We want to free rust_obj when ret gets drop()'d, not rust_obj, so wipe rust_obj's pointer and set ret's free() fn", extra_indent).unwrap();
+ writeln!(w, "\t{}rust_obj.inner = std::ptr::null_mut();", extra_indent).unwrap();
+ writeln!(w, "\t{}ret.free = Some({}_free_void);", extra_indent, this_type).unwrap();
+ writeln!(w, "\t{}ret", extra_indent).unwrap();
+ return;
+ }
+ }
+ }
+ write!(w, "{} {{ inner: Box::into_raw(Box::new(ret)), is_owned: true }}", this_type).unwrap();
+ } else if to_c {
+ let new_var = types.write_from_c_conversion_new_var(w, &syn::Ident::new("ret", Span::call_site()), rtype, generics);
+ if new_var {
+ write!(w, "\n\t{}", extra_indent).unwrap();
+ }
+ types.write_from_c_conversion_prefix(w, &*rtype, generics);
+ write!(w, "ret").unwrap();
+ types.write_from_c_conversion_suffix(w, &*rtype, generics);
+ } else {
+ let ret_returned = if let syn::Type::Reference(_) = &**rtype { true } else { false };
+ let new_var = types.write_to_c_conversion_new_var(w, &syn::Ident::new("ret", Span::call_site()), &rtype, generics, true);
+ if new_var {
+ write!(w, "\n\t{}", extra_indent).unwrap();
+ }
+ types.write_to_c_conversion_inline_prefix(w, &rtype, generics, true);
+ write!(w, "{}ret", if ret_returned && !new_var { "*" } else { "" }).unwrap();
+ types.write_to_c_conversion_inline_suffix(w, &rtype, generics, true);
+ }
+ }
+ _ => {},
+ }
+}
+
+/// Prints concrete generic parameters for a struct/trait/function, including the less-than and
+/// greater-than symbols, if any generic parameters are defined.
+pub fn maybe_write_generics<W: std::io::Write>(w: &mut W, generics: &syn::Generics, types: &TypeResolver, concrete_lifetimes: bool) {
+ let mut gen_types = GenericTypes::new();
+ assert!(gen_types.learn_generics(generics, types));
+ if !generics.params.is_empty() {
+ write!(w, "<").unwrap();
+ for (idx, generic) in generics.params.iter().enumerate() {
+ match generic {
+ syn::GenericParam::Type(type_param) => {
+ let mut printed_param = false;
+ for bound in type_param.bounds.iter() {
+ if let syn::TypeParamBound::Trait(trait_bound) = bound {
+ assert_simple_bound(&trait_bound);
+ write!(w, "{}{}", if idx != 0 { ", " } else { "" }, gen_types.maybe_resolve_ident(&type_param.ident).unwrap()).unwrap();
+ if printed_param {
+ unimplemented!("Can't print generic params that have multiple non-lifetime bounds");
+ }
+ printed_param = true;
+ }
+ }
+ },
+ syn::GenericParam::Lifetime(lt) => {
+ if concrete_lifetimes {
+ write!(w, "'static").unwrap();
+ } else {
+ write!(w, "{}'{}", if idx != 0 { ", " } else { "" }, lt.lifetime.ident).unwrap();
+ }
+ },
+ _ => unimplemented!(),
+ }
+ }
+ write!(w, ">").unwrap();
+ }
+}
+
+
projects / rust-lightning / blobdiff