From 3277946b600ce546f849166f7f59b5ac4b539d3e Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Mon, 29 Mar 2021 12:43:00 -0400 Subject: [PATCH] Handle Option<(..)> as a non-transparent container, unlike Option<..> --- c-bindings-gen/src/blocks.rs | 28 ++++++++ c-bindings-gen/src/types.rs | 136 ++++++++++++++++++++++++++--------- 2 files changed, 131 insertions(+), 33 deletions(-) diff --git a/c-bindings-gen/src/blocks.rs b/c-bindings-gen/src/blocks.rs index 47785a7..b662261 100644 --- a/c-bindings-gen/src/blocks.rs +++ b/c-bindings-gen/src/blocks.rs @@ -295,6 +295,34 @@ pub fn write_tuple_block(w: &mut W, mangled_container: &str, writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap(); } +/// Writes out a C-callable concrete Option struct and utility methods +pub fn write_option_block(w: &mut W, mangled_container: &str, inner_type: &str, clonable: bool) { + writeln!(w, "#[repr(C)]").unwrap(); + if clonable { + writeln!(w, "#[derive(Clone)]").unwrap(); + } + writeln!(w, "pub enum {} {{", mangled_container).unwrap(); + writeln!(w, "\tSome({}),", inner_type).unwrap(); + writeln!(w, "\tNone").unwrap(); + writeln!(w, "}}").unwrap(); + + writeln!(w, "impl {} {{", mangled_container).unwrap(); + writeln!(w, "\t#[allow(unused)] pub(crate) fn is_some(&self) -> bool {{").unwrap(); + writeln!(w, "\t\tif let Self::Some(_) = self {{ true }} else {{ false }}").unwrap(); + writeln!(w, "\t}}").unwrap(); + writeln!(w, "\t#[allow(unused)] pub(crate) fn take(mut self) -> {} {{", inner_type).unwrap(); + writeln!(w, "\t\tif let Self::Some(v) = self {{ v }} else {{ unreachable!() }}").unwrap(); + writeln!(w, "\t}}").unwrap(); + writeln!(w, "}}").unwrap(); + + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap(); + if clonable { + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{ orig.clone() }}", mangled_container, mangled_container, mangled_container).unwrap(); + } +} + /// Prints the docs from a given attribute list unless its tagged no export pub fn writeln_docs(w: &mut W, attrs: &[syn::Attribute], prefix: &str) { for attr in attrs.iter() { diff --git a/c-bindings-gen/src/types.rs b/c-bindings-gen/src/types.rs index dfc1e41..1454f8b 100644 --- a/c-bindings-gen/src/types.rs +++ b/c-bindings-gen/src/types.rs @@ -970,14 +970,37 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { "crate::c_types" } - /// Returns true if this is a "transparent" container, ie an Option or a container which does + /// Returns true if the path containing the given args is a "transparent" container, ie an + /// Option or a container which does not require a generated continer class. + fn is_transparent_container<'i, I: Iterator>(&self, full_path: &str, _is_ref: bool, mut args: I) -> bool { + if full_path == "Option" { + let inner = args.next().unwrap(); + assert!(args.next().is_none()); + match inner { + syn::Type::Reference(_) => true, + syn::Type::Path(_) => true, + syn::Type::Tuple(_) => false, + _ => unimplemented!(), + } + } else { false } + } + /// Returns true if the path is a "transparent" container, ie an Option or a container which does /// not require a generated continer class. - fn is_transparent_container(&self, full_path: &str, _is_ref: bool) -> bool { - full_path == "Option" + fn is_path_transparent_container(&self, full_path: &syn::Path, generics: Option<&GenericTypes>, is_ref: bool) -> bool { + let inner_iter = match &full_path.segments.last().unwrap().arguments { + syn::PathArguments::None => return false, + syn::PathArguments::AngleBracketed(args) => args.args.iter().map(|arg| { + if let syn::GenericArgument::Type(ref ty) = arg { + ty + } else { unimplemented!() } + }), + syn::PathArguments::Parenthesized(_) => unimplemented!(), + }; + self.is_transparent_container(&self.resolve_path(full_path, generics), is_ref, inner_iter) } /// Returns true if this is a known, supported, non-transparent container. fn is_known_container(&self, full_path: &str, is_ref: bool) -> bool { - (full_path == "Result" && !is_ref) || (full_path == "Vec" && !is_ref) || full_path.ends_with("Tuple") + (full_path == "Result" && !is_ref) || (full_path == "Vec" && !is_ref) || full_path.ends_with("Tuple") || full_path == "Option" } fn to_c_conversion_container_new_var<'b>(&self, generics: Option<&GenericTypes>, full_path: &str, is_ref: bool, single_contained: Option<&syn::Type>, var_name: &syn::Ident, var_access: &str) // Returns prefix + Vec<(prefix, var-name-to-inline-convert)> + suffix @@ -1054,22 +1077,34 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { } if let Some(t) = single_contained { - let mut v = Vec::new(); - let ret_ref = self.write_empty_rust_val_check_suffix(generics, &mut v, t); - let s = String::from_utf8(v).unwrap(); - match ret_ref { - EmptyValExpectedTy::ReferenceAsPointer => - return Some(("if ", vec![ - (format!("{} {{ None }} else {{ Some(", s), format!("unsafe {{ &mut *{} }}", var_access)) - ], ") }", ContainerPrefixLocation::NoPrefix)), - EmptyValExpectedTy::OwnedPointer => - return Some(("if ", vec![ - (format!("{} {{ None }} else {{ Some(", s), format!("unsafe {{ *Box::from_raw({}) }}", var_access)) - ], ") }", ContainerPrefixLocation::NoPrefix)), - EmptyValExpectedTy::NonPointer => - return Some(("if ", vec![ - (format!("{} {{ None }} else {{ Some(", s), format!("{}", var_access)) - ], ") }", ContainerPrefixLocation::PerConv)), + match t { + syn::Type::Reference(_)|syn::Type::Path(_)|syn::Type::Slice(_) => { + let mut v = Vec::new(); + let ret_ref = self.write_empty_rust_val_check_suffix(generics, &mut v, t); + let s = String::from_utf8(v).unwrap(); + match ret_ref { + EmptyValExpectedTy::ReferenceAsPointer => + return Some(("if ", vec![ + (format!("{} {{ None }} else {{ Some(", s), format!("unsafe {{ &mut *{} }}", var_access)) + ], ") }", ContainerPrefixLocation::NoPrefix)), + EmptyValExpectedTy::OwnedPointer => { + if let syn::Type::Slice(_) = t { + panic!(); + } + return Some(("if ", vec![ + (format!("{} {{ None }} else {{ Some(", s), format!("unsafe {{ *Box::from_raw({}) }}", var_access)) + ], ") }", ContainerPrefixLocation::NoPrefix)); + } + EmptyValExpectedTy::NonPointer => + return Some(("if ", vec![ + (format!("{} {{ None }} else {{ Some(", s), format!("{}", var_access)) + ], ") }", ContainerPrefixLocation::PerConv)), + } + }, + syn::Type::Tuple(_) => { + return Some(("if ", vec![(".is_some() { Some(".to_string(), format!("{}.take()", var_access))], ") } else { None }", ContainerPrefixLocation::PerConv)) + }, + _ => unimplemented!(), } } else { unreachable!(); } }, @@ -1265,12 +1300,37 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { } } + fn is_real_type_array(&self, resolved_type: &str) -> Option { + if let Some(real_ty) = self.c_type_from_path(&resolved_type, true, false) { + if real_ty.ends_with("]") && real_ty.starts_with("*const [u8; ") { + let mut split = real_ty.split("; "); + split.next().unwrap(); + let tail_str = split.next().unwrap(); + assert!(split.next().is_none()); + let len = &tail_str[..tail_str.len() - 1]; + Some(syn::Type::Array(syn::TypeArray { + bracket_token: syn::token::Bracket { span: Span::call_site() }, + elem: Box::new(syn::Type::Path(syn::TypePath { + qself: None, + path: syn::Path::from(syn::PathSegment::from(syn::Ident::new("u8", Span::call_site()))), + })), + semi_token: syn::Token!(;)(Span::call_site()), + len: syn::Expr::Lit(syn::ExprLit { attrs: Vec::new(), lit: syn::Lit::Int(syn::LitInt::new(len, Span::call_site())) }), + })) + } else { None } + } else { None } + } + /// Prints a suffix to determine if a variable is empty (ie was set by write_empty_rust_val). /// See EmptyValExpectedTy for information on return types. fn write_empty_rust_val_check_suffix(&self, generics: Option<&GenericTypes>, w: &mut W, t: &syn::Type) -> EmptyValExpectedTy { match t { syn::Type::Path(p) => { let resolved = self.resolve_path(&p.path, generics); + if let Some(arr_ty) = self.is_real_type_array(&resolved) { + write!(w, ".data").unwrap(); + return self.write_empty_rust_val_check_suffix(generics, w, &arr_ty); + } if self.crate_types.opaques.get(&resolved).is_some() { write!(w, ".inner.is_null()").unwrap(); EmptyValExpectedTy::NonPointer @@ -1700,7 +1760,7 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { if let Some(aliased_type) = self.crate_types.type_aliases.get(&resolved_path) { return self.write_conversion_new_var_intern(w, ident, var, aliased_type, None, is_ref, ptr_for_ref, to_c, path_lookup, container_lookup, var_prefix, var_suffix); } - if self.is_known_container(&resolved_path, is_ref) || self.is_transparent_container(&resolved_path, is_ref) { + if self.is_known_container(&resolved_path, is_ref) || self.is_path_transparent_container(&p.path, generics, is_ref) { if let syn::PathArguments::AngleBracketed(args) = &p.path.segments.iter().next().unwrap().arguments { convert_container!(resolved_path, args.args.len(), || args.args.iter().map(|arg| { if let syn::GenericArgument::Type(ty) = arg { @@ -1737,7 +1797,7 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { } else if let syn::Type::Reference(ty) = &*s.elem { let tyref = [&*ty.elem]; is_ref = true; - convert_container!("Slice", 1, || tyref.iter()); + convert_container!("Slice", 1, || tyref.iter().map(|t| *t)); unimplemented!("convert_container should return true as container_lookup should succeed for slices"); } else if let syn::Type::Tuple(t) = &*s.elem { // When mapping into a temporary new var, we need to own all the underlying objects. @@ -1932,6 +1992,15 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { if is_clonable { self.crate_types.clonable_types.insert(Self::generated_container_path().to_owned() + "::" + &mangled_container); } + } else if container_type == "Option" { + let mut a_ty: Vec = Vec::new(); + if !self.write_template_generics(&mut a_ty, &mut args.iter().map(|t| *t), generics, is_ref) { return false; } + let ty = String::from_utf8(a_ty).unwrap(); + let is_clonable = self.is_clonable(&ty); + write_option_block(&mut created_container, &mangled_container, &ty, is_clonable); + if is_clonable { + self.crate_types.clonable_types.insert(Self::generated_container_path().to_owned() + "::" + &mangled_container); + } } else { unreachable!(); } @@ -1949,7 +2018,7 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { fn write_c_mangled_container_path_intern (&mut self, w: &mut W, args: Vec<&syn::Type>, generics: Option<&GenericTypes>, ident: &str, is_ref: bool, is_mut: bool, ptr_for_ref: bool, in_type: bool) -> bool { let mut mangled_type: Vec = Vec::new(); - if !self.is_transparent_container(ident, is_ref) { + if !self.is_transparent_container(ident, is_ref, args.iter().map(|a| *a)) { write!(w, "C{}_", ident).unwrap(); write!(mangled_type, "C{}_", ident).unwrap(); } else { assert_eq!(args.len(), 1); } @@ -1957,22 +2026,23 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { macro_rules! write_path { ($p_arg: expr, $extra_write: expr) => { if let Some(subtype) = self.maybe_resolve_path(&$p_arg.path, generics) { - if self.is_transparent_container(ident, is_ref) { - // We dont (yet) support primitives or containers inside transparent - // containers, so check for that first: + if self.is_transparent_container(ident, is_ref, args.iter().map(|a| *a)) { if self.is_primitive(&subtype) { return false; } - if self.is_known_container(&subtype, is_ref) { return false; } if !in_type { if self.c_type_has_inner_from_path(&subtype) { if !self.write_c_path_intern(w, &$p_arg.path, generics, is_ref, is_mut, ptr_for_ref) { return false; } } else { - // Option needs to be converted to a *mut T, ie mut ptr-for-ref - if !self.write_c_path_intern(w, &$p_arg.path, generics, true, true, true) { return false; } + if let Some(arr_ty) = self.is_real_type_array(&subtype) { + if !self.write_c_type_intern(w, &arr_ty, generics, false, true, false) { return false; } + } else { + // Option needs to be converted to a *mut T, ie mut ptr-for-ref + if !self.write_c_path_intern(w, &$p_arg.path, generics, true, true, true) { return false; } + } } } else { write!(w, "{}", $p_arg.path.segments.last().unwrap().ident).unwrap(); } - } else if self.is_known_container(&subtype, is_ref) || self.is_transparent_container(&subtype, is_ref) { + } else if self.is_known_container(&subtype, is_ref) || self.is_path_transparent_container(&$p_arg.path, generics, is_ref) { if !self.write_c_mangled_container_path_intern(w, Self::path_to_generic_args(&$p_arg.path), generics, &subtype, is_ref, is_mut, ptr_for_ref, true) { return false; @@ -2051,7 +2121,7 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { } else { return false; } } else { return false; } } - if self.is_transparent_container(ident, is_ref) { return true; } + if self.is_transparent_container(ident, is_ref, args.iter().map(|a| *a)) { return true; } // Push the "end of type" Z write!(w, "Z").unwrap(); write!(mangled_type, "Z").unwrap(); @@ -2060,7 +2130,7 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { self.check_create_container(String::from_utf8(mangled_type).unwrap(), ident, args, generics, is_ref) } fn write_c_mangled_container_path(&mut self, w: &mut W, args: Vec<&syn::Type>, generics: Option<&GenericTypes>, ident: &str, is_ref: bool, is_mut: bool, ptr_for_ref: bool) -> bool { - if !self.is_transparent_container(ident, is_ref) { + if !self.is_transparent_container(ident, is_ref, args.iter().map(|a| *a)) { write!(w, "{}::", Self::generated_container_path()).unwrap(); } self.write_c_mangled_container_path_intern(w, args, generics, ident, is_ref, is_mut, ptr_for_ref, false) @@ -2109,7 +2179,7 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> { return false; } if let Some(full_path) = self.maybe_resolve_path(&p.path, generics) { - if self.is_known_container(&full_path, is_ref) || self.is_transparent_container(&full_path, is_ref) { + if self.is_known_container(&full_path, is_ref) || self.is_path_transparent_container(&p.path, generics, is_ref) { return self.write_c_mangled_container_path(w, Self::path_to_generic_args(&p.path), generics, &full_path, is_ref, is_mut, ptr_for_ref); } if let Some(aliased_type) = self.crate_types.type_aliases.get(&full_path).cloned() { -- 2.30.2