如何在Rust中运行编译的生锈代码

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闭合 2年前。

Answer 1

如果您真的想要这样的东西（我怀疑），这里有两个非常丑陋的解决方案。

第一个生成一些源代码，对其进行编译以获取可执行文件，然后在另一个过程中运行可执行文件。

第二个生成一些源代码，对其进行编译以获取动态库，然后加载此库（作为插件）并访问生成的函数的符号，以便从当前过程中调用它。

所有这些都认为您可以在执行平台上使用Rust工具链。
名称是硬编码的，并且特定于我的平台（UNIX）；为了适应各种平台，可能需要一些逻辑。
可以将临时目录用于源代码，可执行文件和库，以便以后清洁所有内容，但这是一个细节。

fn code_for_another_process() -> Result<(), Box<dyn std::error::Error>> {
    let exe_name = "./rust_prog";
    let code_name = "rust_prog.rs";
    let mut file = std::fs::File::create(code_name)?;
    use std::io::Write;
    file.write_all(
        "fn main() {\n\
             println!(\"in another process\");\n\
         }\n"
        .as_bytes(),
    )?;
    drop(file); // ensure file is closed
    let comp_status = std::process::Command::new("rustc")
        .arg(code_name)
        .status()?;
    if comp_status.success() {
        println!("~~~~ compilation of {} OK ~~~~", code_name);
        let run_status = std::process::Command::new(exe_name).status()?;
        if run_status.success() {
            println!("~~~~ execution of {} OK ~~~~", exe_name);
        }
    }
    Ok(())
}

fn code_for_this_process() -> Result<(), Box<dyn std::error::Error>> {
    let lib_name = "./librust_lib.so";
    let code_name = "rust_lib.rs";
    let mut file = std::fs::File::create(code_name)?;
    use std::io::Write;
    file.write_all(
        "#[no_mangle]\n\
        pub extern \"C\" fn call_me(arg: i32) -> i32 {\n\
             println!(\"called with {}\", arg);\n\
             arg*2
         }\n"
        .as_bytes(),
    )?;
    drop(file); // ensure file is closed
    let comp_status = std::process::Command::new("rustc")
        .arg("--crate-type")
        .arg("cdylib")
        .arg(code_name)
        .status()?;
    if comp_status.success() {
        println!("~~~~ compilation of {} OK ~~~~", code_name);
        unsafe {
            // requires dependency   libloading = "0.7"
            let lib = libloading::Library::new(lib_name)?;
            let call_me: libloading::Symbol<
                unsafe extern "C" fn(i32) -> i32,
            > = lib.get(b"call_me")?;
            for i in 0..5 {
                println!("--> {}", call_me(i));
            }
        }
    }
    Ok(())
}

fn main() -> Result<(), Box<dyn std::error::Error>> {
    code_for_another_process()?;
    code_for_this_process()?;
    Ok(())
}
/*
~~~~ compilation of rust_prog.rs OK ~~~~
in another process
~~~~ execution of ./rust_prog OK ~~~~
~~~~ compilation of rust_lib.rs OK ~~~~
called with 0
--> 0
called with 1
--> 2
called with 2
--> 4
called with 3
--> 6
called with 4
--> 8
*/