CS452 Lab05 - Sample 1 (Rust)

main.rs

use core::ffi::c_void; // FFI: Foreign Function Interface
use libc::{c_int, shmid_ds};
use libc::{shmat, shmctl, shmdt, shmget};
use libc::{IPC_PRIVATE, IPC_RMID, S_IRUSR, S_IWUSR};

const FOO: usize = 4096;

fn main() {
    println!("Hello, world!");
    let shm_ptr: *mut c_void;
    unsafe {
        let shm_id = shmget(IPC_PRIVATE, FOO, (S_IRUSR | S_IWUSR) as c_int);
        if shm_id < 0 {
            panic!("I can't get no..");
        }
        println!("Shared memory id {}", shm_id);
        shm_ptr = shmat(shm_id, 0 as *const c_void, 0);
        if shm_ptr == 0xFFFFFFFFFFFFFFFF as *mut c_void {
            panic!("Can't attach");
        }
        println!("Value a = {:x}", shm_ptr as usize);
        println!("Value b = {:x}", shm_ptr as usize + FOO);
        if shmdt(shm_ptr) < 0 {
            panic!("Just can't let go")
        }
        if shmctl(shm_id, IPC_RMID, 0 as *mut shmid_ds) < 0 {
            panic!("Can't deallocate");
        }
    }
}