elf_loader 0.15.0

A no_std-friendly ELF loader, runtime linker, and JIT linker for Rust.
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#[path = "common/mod.rs"]
mod fixture_support;

use elf_loader::{
    Loader, Result,
    image::{ModuleHandle, SyntheticModule, SyntheticSymbol},
};

fn host_symbols() -> ModuleHandle {
    fn print(s: &str) {
        println!("{}", s);
    }

    SyntheticModule::new(
        "__host",
        [SyntheticSymbol::function("print", print as *const ())],
    )
    .into()
}

fn main() -> Result<()> {
    unsafe { std::env::set_var("RUST_LOG", "trace") };
    env_logger::init();

    let fixtures = fixture_support::ensure_all();
    let mut loader = Loader::new();
    let host = host_symbols();
    let liba = loader
        .load_dylib(fixtures.liba_str())?
        .relocator()
        .scope([host.clone()])
        .relocate()?;
    let libb = loader
        .load_dylib(fixtures.libb_str())?
        .relocator()
        .scope([host.clone()])
        .extend_scope([&liba])
        .relocate()?;
    let libc = loader
        .load_dylib(fixtures.libc_str())?
        .relocator()
        .scope([host])
        .extend_scope([&liba, &libb])
        .relocate()?;
    let f = unsafe { liba.get::<fn() -> i32>("a").unwrap() };
    assert!(f() == 1);
    let f = unsafe { libb.get::<fn() -> i32>("b").unwrap() };
    assert!(f() == 2);
    let f = unsafe { libc.get::<fn() -> i32>("c").unwrap() };
    assert!(f() == 3);
    Ok(())
}