| commit | 76e52a6f845b0713961966ded00721761b08e094 | [log] [tgz] |
|---|---|---|
| author | Devin Jeanpierre <jeanpierreda@google.com> | Mon Sep 09 15:44:58 2024 -0700 |
| committer | Copybara-Service <copybara-worker@google.com> | Mon Sep 09 15:46:06 2024 -0700 |
| tree | d09be9fd270df6b63385cdca1d3a0d3e03996e6e | |
| parent | 13fa755b171246ac209d6ae3e89dd930520b124d [diff] |
Pass feature flags in from aspect hints down to cc_bindings_from_rs. This is not completely tested, because bazel unit testing is very troublesome, though I can do it. It's my hope I can get away with integration tests when this is actually used, and golden/unit tests for the trivial stuff. PiperOrigin-RevId: 672700966 Change-Id: Icc5ad759afa077b832747bef22e6639194a63f46
NOTE: Crubit currently expects deep integration with the build system, and is difficult to deploy to environments dissimilar to Google's monorepo. We do not have our tooling set up to accept external contributions at this time.
Crubit is a bidirectional bindings generator for C++ and Rust, with the goal of integrating the C++ and Rust ecosystems.
Support for calling FFI-friendly C++ from Rust is in progress.
Support for calling Rust from C++ will arrive in 2024H2.
Consider the following C++ function:
extern "C" bool IsGreater(int lhs, int rhs);
This function, if present in a header file which is processed by Crubit, becomes callable from Rust as if it were defined as:
pub fn IsGreater(lhs: ffi::c_int, rhs: ffi::c_int) -> bool {...}
Note: There are some temporary restrictions on the API shape. For example, functions that are not extern "C", or that accept a type like std::string, can't be called from Rust directly via Crubit. These restrictions will be relaxed over time.
Here are some resources for getting started with Crubit:
Rust Bindings for C++ Libraries is a detailed walkthrough on how to use C++ from Rust using Crubit.
The examples/cpp/ directory has copy-pastable examples of calling C++ from Rust, together with snapshots of what the generated Rust interface looks like.
$ apt install clang lld bazel $ git clone git@github.com:google/crubit.git $ cd crubit $ bazel build --linkopt=-fuse-ld=/usr/bin/ld.lld //rs_bindings_from_cc:rs_bindings_from_cc_impl
$ git clone https://github.com/llvm/llvm-project $ cd llvm-project $ CC=clang CXX=clang++ cmake -S llvm -B build -DLLVM_ENABLE_PROJECTS='clang' -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=install $ cmake --build build -j $ # wait... $ cmake --install build $ cd ../crubit $ LLVM_INSTALL_PATH=../llvm-project/install bazel build //rs_bindings_from_cc:rs_bindings_from_cc_impl