<!-- Generated with Stardoc: http://skydoc.bazel.build -->
# Rust Bindgen

* [rust_bindgen_library](#rust_bindgen_library)
* [rust_bindgen_dependencies](#rust_bindgen_dependencies)
* [rust_bindgen_register_toolchains](#rust_bindgen_register_toolchains)
* [rust_bindgen_toolchain](#rust_bindgen_toolchain)
* [rust_bindgen](#rust_bindgen)


## Overview

These rules are for using [Bindgen][bindgen] to generate [Rust][rust] bindings to C (and some C++) libraries.

[rust]: http://www.rust-lang.org/
[bindgen]: https://github.com/rust-lang/rust-bindgen

See the [bindgen example](https://github.com/bazelbuild/rules_rust/tree/main/examples/ffi/rust_calling_c/simple/BUILD.bazel#L9) for a more complete example of use.

### 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](https://bazelbuild.github.io/rules_rust/#setup)):

```python
load("@rules_rust//bindgen:repositories.bzl", "rust_bindgen_dependencies", "rust_bindgen_register_toolchains")

rust_bindgen_dependencies()

rust_bindgen_register_toolchains()
```

---

---


<a id="rust_bindgen"></a>

## rust_bindgen

<pre>
rust_bindgen(<a href="#rust_bindgen-name">name</a>, <a href="#rust_bindgen-bindgen_flags">bindgen_flags</a>, <a href="#rust_bindgen-cc_lib">cc_lib</a>, <a href="#rust_bindgen-clang_flags">clang_flags</a>, <a href="#rust_bindgen-header">header</a>, <a href="#rust_bindgen-rustfmt">rustfmt</a>)
</pre>

Generates a rust source file from a cc_library and a header.

**ATTRIBUTES**


| Name  | Description | Type | Mandatory | Default |
| :------------- | :------------- | :------------- | :------------- | :------------- |
| <a id="rust_bindgen-name"></a>name |  A unique name for this target.   | <a href="https://bazel.build/concepts/labels#target-names">Name</a> | required |  |
| <a id="rust_bindgen-bindgen_flags"></a>bindgen_flags |  Flags to pass directly to the bindgen executable. See https://rust-lang.github.io/rust-bindgen/ for details.   | List of strings | optional | <code>[]</code> |
| <a id="rust_bindgen-cc_lib"></a>cc_lib |  The cc_library that contains the <code>.h</code> file. This is used to find the transitive includes.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |
| <a id="rust_bindgen-clang_flags"></a>clang_flags |  Flags to pass directly to the clang executable.   | List of strings | optional | <code>[]</code> |
| <a id="rust_bindgen-header"></a>header |  The <code>.h</code> file to generate bindings for.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |
| <a id="rust_bindgen-rustfmt"></a>rustfmt |  Enable or disable running rustfmt on the generated file.   | Boolean | optional | <code>True</code> |


<a id="rust_bindgen_toolchain"></a>

## rust_bindgen_toolchain

<pre>
rust_bindgen_toolchain(<a href="#rust_bindgen_toolchain-name">name</a>, <a href="#rust_bindgen_toolchain-bindgen">bindgen</a>, <a href="#rust_bindgen_toolchain-clang">clang</a>, <a href="#rust_bindgen_toolchain-libclang">libclang</a>, <a href="#rust_bindgen_toolchain-libstdcxx">libstdcxx</a>, <a href="#rust_bindgen_toolchain-rustfmt">rustfmt</a>)
</pre>

The tools required for the `rust_bindgen` rule.

This rule depends on the [`bindgen`](https://crates.io/crates/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.

```python
load("@rules_rust//bindgen:bindgen.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](https://docs.bazel.build/versions/master/toolchains.html).


**ATTRIBUTES**


| Name  | Description | Type | Mandatory | Default |
| :------------- | :------------- | :------------- | :------------- | :------------- |
| <a id="rust_bindgen_toolchain-name"></a>name |  A unique name for this target.   | <a href="https://bazel.build/concepts/labels#target-names">Name</a> | required |  |
| <a id="rust_bindgen_toolchain-bindgen"></a>bindgen |  The label of a <code>bindgen</code> executable.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |
| <a id="rust_bindgen_toolchain-clang"></a>clang |  The label of a <code>clang</code> executable.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |
| <a id="rust_bindgen_toolchain-libclang"></a>libclang |  A cc_library that provides bindgen's runtime dependency on libclang.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |
| <a id="rust_bindgen_toolchain-libstdcxx"></a>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.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |
| <a id="rust_bindgen_toolchain-rustfmt"></a>rustfmt |  The label of a <code>rustfmt</code> executable. If this is not provided, falls back to the rust_toolchain rustfmt.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional | <code>None</code> |


<a id="rust_bindgen_dependencies"></a>

## rust_bindgen_dependencies

<pre>
rust_bindgen_dependencies()
</pre>

Declare dependencies needed for bindgen.


<a id="rust_bindgen_library"></a>

## rust_bindgen_library

<pre>
rust_bindgen_library(<a href="#rust_bindgen_library-name">name</a>, <a href="#rust_bindgen_library-header">header</a>, <a href="#rust_bindgen_library-cc_lib">cc_lib</a>, <a href="#rust_bindgen_library-bindgen_flags">bindgen_flags</a>, <a href="#rust_bindgen_library-clang_flags">clang_flags</a>, <a href="#rust_bindgen_library-rustfmt">rustfmt</a>, <a href="#rust_bindgen_library-kwargs">kwargs</a>)
</pre>

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**


| Name  | Description | Default Value |
| :------------- | :------------- | :------------- |
| <a id="rust_bindgen_library-name"></a>name |  A unique name for this target.   |  none |
| <a id="rust_bindgen_library-header"></a>header |  The label of the .h file to generate bindings for.   |  none |
| <a id="rust_bindgen_library-cc_lib"></a>cc_lib |  The label of the cc_library that contains the .h file. This is used to find the transitive includes.   |  none |
| <a id="rust_bindgen_library-bindgen_flags"></a>bindgen_flags |  Flags to pass directly to the bindgen executable. See https://rust-lang.github.io/rust-bindgen/ for details.   |  `None` |
| <a id="rust_bindgen_library-clang_flags"></a>clang_flags |  Flags to pass directly to the clang executable.   |  `None` |
| <a id="rust_bindgen_library-rustfmt"></a>rustfmt |  Enable or disable running rustfmt on the generated file.   |  `True` |
| <a id="rust_bindgen_library-kwargs"></a>kwargs |  Arguments to forward to the underlying <code>rust_library</code> rule.   |  none |


<a id="rust_bindgen_register_toolchains"></a>

## rust_bindgen_register_toolchains

<pre>
rust_bindgen_register_toolchains(<a href="#rust_bindgen_register_toolchains-register_toolchains">register_toolchains</a>)
</pre>

Registers the default toolchains for the `rules_rust` [bindgen][bg] rules.

[bg]: https://rust-lang.github.io/rust-bindgen/


**PARAMETERS**


| Name  | Description | Default Value |
| :------------- | :------------- | :------------- |
| <a id="rust_bindgen_register_toolchains-register_toolchains"></a>register_toolchains |  Whether or not to register toolchains.   |  `True` |