cpp-0.5.9/.cargo_vcs_info.json0000644000000001410000000000100116250ustar { "git": { "sha1": "9eda55bdc2922fa50c36cee80990a96bdf5e65c2" }, "path_in_vcs": "cpp" }cpp-0.5.9/Cargo.toml0000644000000017620000000000100076350ustar # THIS FILE IS AUTOMATICALLY GENERATED BY CARGO # # When uploading crates to the registry Cargo will automatically # "normalize" Cargo.toml files for maximal compatibility # with all versions of Cargo and also rewrite `path` dependencies # to registry (e.g., crates.io) dependencies. # # If you are reading this file be aware that the original Cargo.toml # will likely look very different (and much more reasonable). # See Cargo.toml.orig for the original contents. [package] edition = "2018" name = "cpp" version = "0.5.9" authors = [ "Nika Layzell ", "Olivier Goffart ", ] description = "Inline C++ code closures" documentation = "https://docs.rs/cpp" readme = "README.md" keywords = [ "c", "cxx", "ffi", "compiler", ] categories = ["development-tools::ffi"] license = "MIT/Apache-2.0" repository = "https://github.com/mystor/rust-cpp" [dependencies.cpp_macros] version = "=0.5.9" [dev-dependencies.cpp_build] version = "=0.5.9" cpp-0.5.9/Cargo.toml.orig000064400000000000000000000010771046102023000133150ustar 00000000000000[package] name = "cpp" version = "0.5.9" authors = ["Nika Layzell ", "Olivier Goffart "] edition = "2018" description = "Inline C++ code closures" readme = "../README.md" license = "MIT/Apache-2.0" keywords = ["c", "cxx", "ffi", "compiler"] categories = ["development-tools::ffi"] repository = "https://github.com/mystor/rust-cpp" documentation = "https://docs.rs/cpp" [dependencies] cpp_macros = { version = "=0.5.9", path = "../cpp_macros" } [dev-dependencies] cpp_build = { version = "=0.5.9", path = "../cpp_build" } cpp-0.5.9/README.md000064400000000000000000000032751046102023000117070ustar 00000000000000# rust-cpp - Embed C++ code directly in Rust [![Documentation](https://docs.rs/cpp/badge.svg)](https://docs.rs/cpp/) ## Overview `rust-cpp` is a build tool & macro which enables you to write C++ code inline in your rust code. ```rust let name = std::ffi::CString::new("World").unwrap(); let name_ptr = name.as_ptr(); let r = unsafe { cpp!([name_ptr as "const char *"] -> u32 as "int32_t" { std::cout << "Hello, " << name_ptr << std::endl; return 42; }) }; assert_eq!(r, 42) ``` The crate also help to expose some C++ class to Rust by automatically implementing trait such as Drop, Clone (if the C++ type can be copied), and others ```rust cpp_class!{ #[derive(PartialEq)] unsafe struct MyClass as "std::unique_ptr" } ``` ## Usage For usage information and in-depth documentation, see the [`cpp` crate module level documentation](https://docs.rs/cpp). ## Differences with the [`cxx`](https://cxx.rs) crate This crate allows to write C++ code "inline" within your Rust functions, while with the [`cxx`](https://cxx.rs) crate, you have to write a bit of boiler plate to have calls to functions declared in a different `.cpp` file. Having C++ code inline might be helpful when trying to call to a C++ library and that one may wish to make plenty of call to small snippets. It can otherwise be fastidious to write and maintain the boiler plate for many small functions in different places. These crate can also be used in together. The `cxx` crate offer some useful types such as `CxxString` that can also be used with this crate. The `cxx` bridge does more type checking which can avoid some classes of errors. While this crate can only check for equal size and alignment. cpp-0.5.9/src/lib.rs000064400000000000000000000370121046102023000123270ustar 00000000000000#![allow(clippy::needless_doctest_main)] //! This crate `cpp` provides macros that allow embedding arbitrary C++ code. //! //! # Usage //! //! This crate must be used in tandem with the [`cpp_build`](https://docs.rs/cpp_build) crate. A basic Cargo //! project which uses these projects would have a structure like the following: //! //! ```text //! crate //! |-- Cargo.toml //! |-- src //! |-- main.rs //! |-- build.rs //! ``` //! //! Where the files look like the following: //! //! #### Cargo.toml //! //! ```toml //! [package] //! build = "build.rs" //! //! [dependencies] //! cpp = "0.5" //! //! [build-dependencies] //! cpp_build = "0.5" //! ``` //! //! #### build.rs //! //! ```no_run //! extern crate cpp_build; //! fn main() { //! cpp_build::build("src/main.rs"); //! } //! ``` //! //! #### main.rs //! //! ```ignore //! # // tested in test/src/examples.rs //! use cpp::cpp; //! //! cpp!{{ //! #include //! }} //! //! fn main() { //! let name = std::ffi::CString::new("World").unwrap(); //! let name_ptr = name.as_ptr(); //! let r = unsafe { //! cpp!([name_ptr as "const char *"] -> u32 as "int32_t" { //! std::cout << "Hello, " << name_ptr << std::endl; //! return 42; //! }) //! }; //! assert_eq!(r, 42) //! } //! ``` //! //! # Build script //! //! Use the `cpp_build` crates from your `build.rs` script. //! The same version of `cpp_build` and `cpp` crates should be used. //! You can simply use the `cpp_build::build` function, or the `cpp_build::Config` //! struct if you want more option. //! //! Behind the scene, it uses the `cc` crate. //! //! ## Using external libraries //! //! Most likely you will want to link against external libraries. You need to tell cpp_build //! about the include path and other flags via `cpp_build::Config` and you need to let cargo //! know about the link. More info in the [cargo docs](https://doc.rust-lang.org/cargo/reference/build-scripts.html). //! //! Your `build.rs` could look like this: //! //! ```no_run //! fn main() { //! let include_path = "/usr/include/myexternallib"; //! let lib_path = "/usr/lib/myexternallib"; //! cpp_build::Config::new().include(include_path).build("src/lib.rs"); //! println!("cargo:rustc-link-search={}", lib_path); //! println!("cargo:rustc-link-lib=myexternallib"); //! } //! ``` //! //! (But you probably want to allow to configure the path via environment variables or //! find them using some external tool such as the `pkg-config` crate, instead of hardcoding //! them in the source) //! //! # Limitations //! //! As with all procedure macro crates we also need to parse Rust source files to //! extract C++ code. That leads to the fact that some of the language features //! might not be supported in full. One example is the attributes. Only a limited //! number of attributes is supported, namely: `#[path = "..."]` for `mod` //! declarations to specify an alternative path to the module file and //! `#[cfg(feature = "...")]` for `mod` declarations to conditionally include the //! module into the parsing process. Please note that the latter is only supported //! in its simplest form: straight-forward `feature = "..."` without any //! additional conditions, `cfg!` macros are also not supported at the moment. //! //! Since the C++ code is included within a rust file, the C++ code must obey both //! the Rust and the C++ lexing rules. For example, Rust supports nested block comments //! (`/* ... /* ... */ ... */`) while C++ does not, so nested comments not be used in the //! `cpp!` macro. Also the Rust lexer will not understand the C++ raw literal, nor all //! the C++ escape sequences within literal, so only string literals that are both valid //! in Rust and in C++ should be used. The same applies for group separators in numbers. //! Be careful to properly use `#if` / `#else` / `#endif`, and not have unbalanced delimiters. #![no_std] #[macro_use] #[allow(unused_imports)] extern crate cpp_macros; #[doc(hidden)] pub use cpp_macros::*; /// Internal macro which is used to locate the `rust!` invocations in the /// C++ code embedded in `cpp!` invocation, to translate them into `extern` /// functions #[doc(hidden)] #[macro_export] macro_rules! __cpp_internal { (@find_rust_macro [$($a:tt)*] rust!($($rust_body:tt)*) $($rest:tt)*) => { $crate::__cpp_internal!{ @expand_rust_macro [$($a)*] $($rust_body)* } $crate::__cpp_internal!{ @find_rust_macro [$($a)*] $($rest)* } }; (@find_rust_macro [$($a:tt)*] ( $($in:tt)* ) $($rest:tt)* ) => { $crate::__cpp_internal!{ @find_rust_macro [$($a)*] $($in)* $($rest)* } }; (@find_rust_macro [$($a:tt)*] [ $($in:tt)* ] $($rest:tt)* ) => { $crate::__cpp_internal!{ @find_rust_macro [$($a)*] $($in)* $($rest)* } }; (@find_rust_macro [$($a:tt)*] { $($in:tt)* } $($rest:tt)* ) => { $crate::__cpp_internal!{ @find_rust_macro [$($a)*] $($in)* $($rest)* } }; (@find_rust_macro [$($a:tt)*] $t:tt $($rest:tt)*) => { $crate::__cpp_internal!{ @find_rust_macro [$($a)*] $($rest)* } }; (@find_rust_macro [$($a:tt)*]) => {}; (@expand_rust_macro [$($a:tt)*] $i:ident [$($an:ident : $at:ty as $ac:tt),*] {$($body:tt)*}) => { #[allow(non_snake_case)] #[allow(unused_unsafe)] #[cfg_attr(feature = "cargo-clippy", allow(clippy::forget_copy))] #[cfg_attr(feature = "cargo-clippy", allow(clippy::forget_ref))] #[doc(hidden)] $($a)* unsafe extern "C" fn $i($($an : *const $at),*) { $(let $an : $at = unsafe { $an.read() };)* (|| { $($body)* })(); $(::core::mem::forget($an);)* } }; (@expand_rust_macro [$($a:tt)*] $i:ident [$($an:ident : $at:ty as $ac:tt),*] -> $rt:ty as $rc:tt {$($body:tt)*}) => { #[allow(non_snake_case)] #[allow(unused_unsafe)] #[cfg_attr(feature = "cargo-clippy", allow(clippy::forget_copy))] #[cfg_attr(feature = "cargo-clippy", allow(clippy::forget_ref))] #[doc(hidden)] $($a)* unsafe extern "C" fn $i($($an : *const $at, )* rt : *mut $rt) -> *mut $rt { $(let $an : $at = unsafe { $an.read() };)* { #[allow(unused_mut)] let mut lambda = || {$($body)*}; unsafe { ::core::ptr::write(rt, lambda()) }; } $(::core::mem::forget($an);)* rt } }; (@expand_rust_macro $($invalid:tt)*) => { compile_error!(concat!( "Cannot parse rust! macro: ", stringify!([ $($invalid)* ]) )) }; } /// This macro is used to embed arbitrary C++ code. /// /// There are two variants of the `cpp!` macro. The first variant is used for /// raw text inclusion. Text is included into the generated `C++` file in the /// order which they were defined, inlining module declarations. /// /// ```ignore /// cpp! {{ /// #include /// #include /// }} /// ``` /// /// The second variant is used to embed C++ code within Rust code. A list of /// variable names which should be captured are taken as the first argument, /// with their corresponding C++ type. The body is compiled as a C++ function. /// /// This variant of the macro may only be invoked in expression context, and /// requires an `unsafe` block, as it is performing FFI. /// /// ```ignore /// let y: i32 = 10; /// let mut z: i32 = 20; /// let x: i32 = unsafe { cpp!([y as "int32_t", mut z as "int32_t"] -> i32 as "int32_t" { /// z++; /// return y + z; /// })}; /// ``` /// /// You can also put the unsafe keyword as the first keyword of the `cpp!` macro, which /// has the same effect as putting the whole macro in an `unsafe` block: /// /// ```ignore /// let x: i32 = cpp!(unsafe [y as "int32_t", mut z as "int32_t"] -> i32 as "int32_t" { /// z++; /// return y + z; /// }); /// ``` /// /// ## rust! pseudo-macro /// /// The `cpp!` macro can contain, in the C++ code, a `rust!` sub-macro, which allows /// the inclusion of Rust code in C++ code. This is useful to /// implement callback or override virtual functions. Example: /// /// ```ignore /// trait MyTrait { /// fn compute_value(&self, x : i32) -> i32; /// } /// /// cpp!{{ /// struct TraitPtr { void *a,*b; }; /// class MyClassImpl : public MyClass { /// public: /// TraitPtr m_trait; /// int computeValue(int x) const override { /// return rust!(MCI_computeValue [m_trait : &MyTrait as "TraitPtr", x : i32 as "int"] /// -> i32 as "int" { /// m_trait.compute_value(x) /// }); /// } /// } /// }} /// ``` /// /// The syntax for the `rust!` macro is: /// ```ignore /// rust!($uniq_ident:ident [$($arg_name:ident : $arg_rust_type:ty as $arg_c_type:tt),*] /// $(-> $ret_rust_type:ty as $rust_c_type:tt)* {$($body:tt)*}) /// ``` /// `uniq_ident` is a unique identifier which will be used to name the `extern` function #[macro_export] macro_rules! cpp { // raw text inclusion ({$($body:tt)*}) => { $crate::__cpp_internal!{ @find_rust_macro [#[no_mangle] pub] $($body)*} }; // inline closure ([$($captures:tt)*] $($rest:tt)*) => { { $crate::__cpp_internal!{ @find_rust_macro [] $($rest)*} #[allow(unused)] #[derive($crate::__cpp_internal_closure)] enum CppClosureInput { Input = (stringify!([$($captures)*] $($rest)*), 0).1 } __cpp_closure_impl![$($captures)*] } }; // wrap unsafe (unsafe $($tail:tt)*) => { unsafe { cpp!($($tail)*) } }; } #[doc(hidden)] pub trait CppTrait { type BaseType; const ARRAY_SIZE: usize; const CPP_TYPE: &'static str; } /// This macro allows wrapping a relocatable C++ struct or class that might have /// a destructor or copy constructor, implementing the `Drop` and `Clone` trait /// appropriately. /// /// ```ignore /// cpp_class!(pub unsafe struct MyClass as "MyClass"); /// impl MyClass { /// fn new() -> Self { /// unsafe { cpp!([] -> MyClass as "MyClass" { return MyClass(); }) } /// } /// fn member_function(&self, param : i32) -> i32 { /// unsafe { cpp!([self as "const MyClass*", param as "int"] -> i32 as "int" { /// return self->member_function(param); /// }) } /// } /// } /// ``` /// /// This will create a Rust struct `MyClass`, which has the same size and /// alignment as the C++ class `MyClass`. It will also implement the `Drop` trait /// calling the destructor, the `Clone` trait calling the copy constructor, if the /// class is copyable (or `Copy` if it is trivially copyable), and `Default` if the class /// is default constructible /// /// ## Derived Traits /// /// The `Default`, `Clone` and `Copy` traits are implicitly implemented if the C++ /// type has the corresponding constructors. /// /// You can add the `#[derive(...)]` attribute in the macro in order to get automatic /// implementation of the following traits: /// /// * The trait `PartialEq` will call the C++ `operator==`. /// * You can add the trait `Eq` if the semantics of the C++ operator are those of `Eq` /// * The trait `PartialOrd` need the C++ `operator<` for that type. `lt`, `le`, `gt` and /// `ge` will use the corresponding C++ operator if it is defined, otherwise it will /// fallback to the less than operator. For PartialOrd::partial_cmp, the `operator<` will /// be called twice. Note that it will never return `None`. /// * The trait `Ord` can also be specified when the semantics of the `operator<` corresponds /// to a total order /// /// ## Safety Warning /// /// Use of this macro is highly unsafe. Only certain C++ classes can be bound /// to, C++ classes may perform arbitrary unsafe operations, and invariants are /// easy to break. /// /// A notable restriction is that this macro only works if the C++ class is /// relocatable. /// /// ## Relocatable classes /// /// In order to be able to we wrapped the C++ class must be relocatable. That means /// that it can be moved in memory using `memcpy`. This restriction exists because /// safe Rust is allowed to move your types around. /// /// Most C++ types which do not contain self-references will be compatible, /// although this property cannot be statically checked by `rust-cpp`. /// All types that satisfy `std::is_trivially_copyable` are compatible. /// Maybe future version of the C++ standard would allow a compile-time check: /// [P1144](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1144r4.html) /// /// Unfortunately, as the STL often uses internal self-references for /// optimization purposes, such as the small-string optimization, this disallows /// most std:: classes. /// But `std::unique_ptr` and `std::shared_ptr` works. /// #[macro_export] macro_rules! cpp_class { ($(#[$($attrs:tt)*])* unsafe struct $name:ident as $type:expr) => { $crate::__cpp_class_internal!{@parse [ $(#[$($attrs)*])* ] [] [unsafe struct $name as $type] } }; ($(#[$($attrs:tt)*])* pub unsafe struct $name:ident as $type:expr) => { $crate::__cpp_class_internal!{@parse [ $(#[$($attrs)*])* ] [pub] [unsafe struct $name as $type] } }; ($(#[$($attrs:tt)*])* pub($($pub:tt)*) unsafe struct $name:ident as $type:expr) => { $crate::__cpp_class_internal!{@parse [ $(#[$($attrs)*])* ] [pub($($pub)*)] [unsafe struct $name as $type] } }; } /// Implementation details for cpp_class! #[doc(hidden)] #[macro_export] macro_rules! __cpp_class_internal { (@parse [$($attrs:tt)*] [$($vis:tt)*] [unsafe struct $name:ident as $type:expr]) => { $crate::__cpp_class_internal!{@parse_attributes [ $($attrs)* ] [] [ #[derive($crate::__cpp_internal_class)] #[repr(C)] $($vis)* struct $name { _opaque : [<$name as $crate::CppTrait>::BaseType ; <$name as $crate::CppTrait>::ARRAY_SIZE + (stringify!($($attrs)* $($vis)* unsafe struct $name as $type), 0).1] } ]} }; (@parse_attributes [] [$($attributes:tt)*] [$($result:tt)*]) => ( $($attributes)* $($result)* ); (@parse_attributes [#[derive($($der:ident),*)] $($tail:tt)* ] [$($attributes:tt)*] [$($result:tt)*] ) => ($crate::__cpp_class_internal!{@parse_derive [$($der),*] @parse_attributes [$($tail)*] [ $($attributes)* ] [ $($result)* ] } ); (@parse_attributes [ #[$m:meta] $($tail:tt)* ] [$($attributes:tt)*] [$($result:tt)*]) => ($crate::__cpp_class_internal!{@parse_attributes [$($tail)*] [$($attributes)* #[$m] ] [ $($result)* ] } ); (@parse_derive [] @parse_attributes $($result:tt)*) => ($crate::__cpp_class_internal!{@parse_attributes $($result)*} ); (@parse_derive [PartialEq $(,$tail:ident)*] $($result:tt)*) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] $($result)*} ); (@parse_derive [PartialOrd $(,$tail:ident)*] $($result:tt)*) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] $($result)*} ); (@parse_derive [Ord $(,$tail:ident)*] $($result:tt)*) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] $($result)*} ); (@parse_derive [Default $(,$tail:ident)*] $($result:tt)*) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] $($result)*} ); (@parse_derive [Clone $(,$tail:ident)*] $($result:tt)*) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] $($result)*} ); (@parse_derive [Copy $(,$tail:ident)*] $($result:tt)*) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] $($result)*} ); (@parse_derive [$i:ident $(,$tail:ident)*] @parse_attributes [$($attr:tt)*] [$($attributes:tt)*] [$($result:tt)*] ) => ( $crate::__cpp_class_internal!{@parse_derive [$($tail),*] @parse_attributes [$($attr)*] [$($attributes)* #[derive($i)] ] [ $($result)* ] } ); }