gut-plugin

辅助库，提供宏以创建gut插件。

gut插件系统加载位于gut目录（wasm）的插件，目录为 $HOME/.gut。

如何创建gut插件

1. 使用cargo创建一个新的库

$ cargo new my_gut_plugin --lib

2. 在Cargo.toml中添加以下内容

[lib]
name = "gut_myplugin"
crate-type = ["cdylib"]

[dependencies]
gut-plugin = "0.1.0"

3. 使用提供的宏导出函数

use std::slice;
use std::str;

// gut_export!([names], [descriptions])
// names: [&str] - the names of the functions to export.
// descriptions: [&str] - the descriptions of the functions to export.
gut_plugin::gut_export!(
  ["my_plugin"],
  ["Prints the provided string"]
);

// all exported functions must have this signature:
//
// #[no_mangle]
// fn_name(ptr: i32, len: i32)
//
// this is becuase gut will invoke the function and pass a string if one is provided.
// example:
// $ gut my_plugin "world"
#[no_mangle]
fn my_plugin(ptr: i32, len: i32) {
  let slice = unsafe { slice::from_raw_parts(ptr as _, len as _) };
  let string_from_host = str::from_utf8(&slice).unwrap();

  println!("Hello {}!", string_from_host)
}

4. 构建

# you may need to add wasm32-wasi target to build wasm
$ rustup target add wasm32-wasi

# build
$ cargo build --target wasm32-wasi --release

# move to gut directory
$ cp target/wasm32-wasi/release/gut_myplugin.wasm $HOME/.gut/