问题：如何正确地hook系统函数？

[loongs-zhang]

fn abs(i: i32) -> i32 {
    unsafe {
        let original = libc::dlsym(libc::RTLD_DEFAULT, "abs".as_ptr() as *const _)
            as *mut fn(i32) -> i32;
        //如何正确地hook系统函数abs?
//这里会调用失败
        let result = (*original)(i);
        println!("{}", result);
        result
    }
}

fn main() {
    println!("{}", abs(-1));
}

[ZhangHanDong]

你要通过 ffi 来调用

use std::os::raw::c_int;
// import an external function from libc
extern "C" {
    fn abs(args: c_int) -> c_int;
}