`c2rust-refactor` has a simple plugin system, which is useful for mitigating the long compile times of the main `c2rust-refactor` binary.


# Plugin API

A plugin is simply a shared library that provides a function with the following
signature:

    #[no_mangle]
    pub fn register_commands(reg: &mut c2rust_refactor::command::Registry) { ... }

`c2rust-refactor` will call the `register_commands` function when the plugin is
loaded, allowing it to add its commands to the command registry.  Those
commands will be available from the command line and editor integration, just
like any built-in command.


# Compiling a plugin

Compile with a command like the following:

```bash
    rustc plugin_stub.rs \
        --crate-type dylib \
        -L target/debug/deps \
        --extern c2rust_refactor=target/debug/libc2rust_refactor.rlib \
        --extern log=target/debug/deps/liblog-d13cea69eadf9021.rlib \
        --extern libc=target/debug/deps/liblibc-245f0779ba681f77.rlib
```

The hashes for `liblog` and `liblibc` may change depending on the details of
your build environment - check the contents of `target/debug/deps` to find 
the right hash.


# Loading plugins

First, pass `c2rust_refactor` the `-P path` option to add a directory to the plugin
search path.  (The search path is empty by default, so no plugins can be
loaded.)  Then pass one or more `-p plugin_name` name options, to load
`libplugin_name.so` for each option.