rules_rust_bindgen
These rules are for using Bindgen to generate Rust bindings to C (and some C++) libraries.
Rules
Setup
To use the Rust bindgen rules, add the following to your WORKSPACE file to add the
external repositories for the Rust bindgen toolchain (in addition to the rust rules setup):
load("@rules_rust_bindgen//:repositories.bzl", "rust_bindgen_dependencies", "rust_bindgen_register_toolchains")
rust_bindgen_dependencies()
rust_bindgen_register_toolchains()
load("@rules_rust_bindgen//:transitive_repositories.bzl", "rust_bindgen_transitive_dependencies")
rust_bindgen_transitive_dependencies()
Bindgen aims to be as hermetic as possible so will end up building libclang from llvm-project from
source. If this is found to be undesirable then no Bindgen related calls should be added to your WORKSPACE and instead
users should define their own repositories using something akin to crate_universe and define their own
toolchains following the instructions for rust_bindgen_toolchain.
rust_bindgen
load("@rules_rust_bindgen//:defs.bzl", "rust_bindgen")
rust_bindgen(name, bindgen_flags, cc_lib, clang_flags, header, merge_cc_lib_objects_into_rlib,
wrap_static_fns)
Generates a rust source file from a cc_library and a header.
ATTRIBUTES
| Name | Description | Type | Mandatory | Default |
|---|---|---|---|---|
| name | A unique name for this target. | Name | required | |
| bindgen_flags | Flags to pass directly to the bindgen executable. See https://rust-lang.github.io/rust-bindgen/ for details. | List of strings | optional | [] |
| cc_lib | The cc_library that contains the .h file. This is used to find the transitive includes. | Label | required | |
| clang_flags | Flags to pass directly to the clang executable. | List of strings | optional | [] |
| header | The .h file to generate bindings for. | Label | required | |
| merge_cc_lib_objects_into_rlib | When True, objects from cc_lib will be copied into the rlib archive produced by the rust_library that depends on this rust_bindgen rule (using BuildInfo provider) | Boolean | optional | True |
| wrap_static_fns | Whether to create a separate .c file for static fns. Requires nightly toolchain, and a header that actually needs this feature (otherwise bindgen won't generate the file and Bazel complains). | Boolean | optional | False |
rust_bindgen_toolchain
load("@rules_rust_bindgen//:defs.bzl", "rust_bindgen_toolchain")
rust_bindgen_toolchain(name, bindgen, clang, default_rustfmt, libclang, libstdcxx)
The tools required for the rust_bindgen rule.
This rule depends on the bindgen binary crate, and it
in turn depends on both a clang binary and the clang library. To obtain these dependencies,
rust_bindgen_dependencies imports bindgen and its dependencies.
load("@rules_rust_bindgen//:defs.bzl", "rust_bindgen_toolchain")
rust_bindgen_toolchain(
name = "bindgen_toolchain_impl",
bindgen = "//my/rust:bindgen",
clang = "//my/clang:clang",
libclang = "//my/clang:libclang.so",
libstdcxx = "//my/cpp:libstdc++",
)
toolchain(
name = "bindgen_toolchain",
toolchain = "bindgen_toolchain_impl",
toolchain_type = "@rules_rust_bindgen//:toolchain_type",
)
This toolchain will then need to be registered in the current WORKSPACE.
For additional information, see the Bazel toolchains documentation.
ATTRIBUTES
| Name | Description | Type | Mandatory | Default |
|---|---|---|---|---|
| name | A unique name for this target. | Name | required | |
| bindgen | The label of a bindgen executable. | Label | optional | None |
| clang | The label of a clang executable. | Label | optional | None |
| default_rustfmt | If set, rust_bindgen targets will always format generated sources with rustfmt. | Boolean | optional | True |
| libclang | A cc_library that provides bindgen's runtime dependency on libclang. | Label | optional | None |
| libstdcxx | A cc_library that satisfies libclang's libstdc++ dependency. This is used to make the execution of clang hermetic. If None, system libraries will be used instead. | Label | optional | None |
rust_bindgen_library
load("@rules_rust_bindgen//:defs.bzl", "rust_bindgen_library")
rust_bindgen_library(name, header, cc_lib, bindgen_flags, bindgen_features, clang_flags,
wrap_static_fns, kwargs)
Generates a rust source file for header, and builds a rust_library.
Arguments are the same as rust_bindgen, and kwargs are passed directly to rust_library.
PARAMETERS