commit | f60650427d7b04042a05fd906fe3ac60b9c1757b | [log] [tgz] |
---|---|---|
author | Marcel Hlopko <hlopko@google.com> | Mon Jul 01 00:17:11 2024 -0700 |
committer | Copybara-Service <copybara-worker@google.com> | Mon Jul 01 00:18:34 2024 -0700 |
tree | b1755124374756779321d6b2c3bfee86b1b38aee | |
parent | 9ec82cc8eb98dcff5e6691c07d4af5efc96da556 [diff] |
Rollback of: Disable Crubit on grpc and targets that disable header parsing. This allows Crubit to work on targets that depend on grpc, as long as they do not transitively include the headers. So, that's a workaround, at least. This is not "strictly correct": a target might disable header parsing because it has a bad header in `srcs`, which isn't relevant to Crubit which only reads `hdrs`. However, it's almost certainly (also) broken in `srcs`. If ever we need to enable Crubit on a target that... PiperOrigin-RevId: 648267674 Change-Id: I35cbdeed7928cfe93b133221b7201ddacb2bf813
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