dlopen 0.1.8

Library for opening and operating on dynamic link libraries (also known as shared objects or shared libraries). This is a modern and more flexible alternative to the already existing libraries like libloading or sharedlib
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#[macro_use]
extern crate const_cstr;
extern crate dlopen;
extern crate libc;
use dlopen::raw::{Library, AddressInfoObtainer};
use libc::{c_char, c_int};
use std::ffi::CStr;

mod commons;
use commons::{example_lib_path, SomeData};

#[test]
fn open_play_close_raw() {
    let lib_path = example_lib_path();
    let lib = Library::open(lib_path).expect("Could not open library");
    let rust_fun_print_something: fn() =
        unsafe { lib.symbol_cstr(const_cstr!("rust_fun_print_something").as_cstr()) }.unwrap();
    rust_fun_print_something(); //should not crash
    let rust_fun_add_one: fn(i32) -> i32 =
        unsafe { lib.symbol_cstr(const_cstr!("rust_fun_add_one").as_cstr()) }.unwrap();
    assert_eq!(rust_fun_add_one(5), 6);
    let c_fun_print_something_else: unsafe extern "C" fn() =
        unsafe { lib.symbol_cstr(const_cstr!("c_fun_print_something_else").as_cstr()) }.unwrap();
    unsafe { c_fun_print_something_else() }; //should not crash
    let c_fun_add_two: unsafe extern "C" fn(c_int) -> c_int =
        unsafe { lib.symbol_cstr(const_cstr!("c_fun_add_two").as_cstr()) }.unwrap();
    assert_eq!(unsafe { c_fun_add_two(2) }, 4);
    let rust_i32: &i32 = unsafe { lib.symbol_cstr(const_cstr!("rust_i32").as_cstr()) }.unwrap();
    assert_eq!(43, *rust_i32);
    let rust_i32_mut: &mut i32 =
        unsafe { lib.symbol_cstr(const_cstr!("rust_i32_mut").as_cstr()) }.unwrap();
    assert_eq!(42, *rust_i32_mut);
    *rust_i32_mut = 55; //should not crash
    //for a change use pointer to obtain its value
    let rust_i32_ptr: *const i32 =
        unsafe { lib.symbol_cstr(const_cstr!("rust_i32_mut").as_cstr()) }.unwrap();
    assert_eq!(55, unsafe { *rust_i32_ptr });
    //the same with C
    let c_int: &c_int = unsafe { lib.symbol_cstr(const_cstr!("c_int").as_cstr()) }.unwrap();
    assert_eq!(45, *c_int);
    //now static c struct

    let c_struct: &SomeData =
        unsafe { lib.symbol_cstr(const_cstr!("c_struct").as_cstr()) }.unwrap();
    assert_eq!(1, c_struct.first);
    assert_eq!(2, c_struct.second);
    //let's play with strings

    let rust_str: &&str = unsafe { lib.symbol_cstr(const_cstr!("rust_str").as_cstr()) }.unwrap();
    assert_eq!("Hello!", *rust_str);
    let c_const_char_ptr: *const c_char =
        unsafe { lib.symbol_cstr(const_cstr!("c_const_char_ptr").as_cstr()) }.unwrap();
    let converted = unsafe { CStr::from_ptr(c_const_char_ptr) }
        .to_str()
        .unwrap();
    assert_eq!(converted, "Hi!");

    ::std::mem::forget(lib);
}

#[test]
fn example_address_info(){
    let lib_path = example_lib_path();
    let lib = Library::open(&lib_path).expect("Could not open library");
    let c_fun_add_two: unsafe extern "C" fn(c_int) -> c_int =
        unsafe { lib.symbol("c_fun_add_two") }.unwrap();
    let aio = AddressInfoObtainer::new();
    let ai = aio.obtain(c_fun_add_two as * const ()).unwrap();
    assert_eq!(&ai.dll_path, lib_path.to_str().unwrap());
    let os = ai.overlapping_symbol.unwrap();
    assert_eq!(os.name, "c_fun_add_two");
    assert_eq!(os.addr, c_fun_add_two as * const ())
}