// Copyright 2022 The ChromiumOS Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

//! Integration tests for vmm-swap feature

mod common;

use base::pagesize;
use base::sys::wait_for_pid;
use base::AsRawDescriptor;
use base::FromRawDescriptor;
use base::IntoRawDescriptor;
use base::SafeDescriptor;
use base::Tube;
use common::*;
use swap::register_regions;
use swap::unregister_regions;
use swap::userfaultfd::Userfaultfd;

#[test]
fn register_region_skip_obsolete_process() {
    let shm = create_shared_memory("test", 3 * pagesize());
    let uffd = create_uffd_for_test();
    let base_addr = shm.base_addr();
    let regions = [base_addr..(base_addr + 3 * pagesize())];
    let (tube_main, tube_child) = Tube::pair().unwrap();
    let pid = unsafe { libc::fork() };
    if pid == 0 {
        // child process
        let uffd = create_uffd_for_test();
        tube_child
            .send(&unsafe { SafeDescriptor::from_raw_descriptor(uffd.as_raw_descriptor()) })
            .unwrap();
        std::process::exit(0);
    }
    let uffd_descriptor = tube_main
        .recv::<SafeDescriptor>()
        .unwrap()
        .into_raw_descriptor();
    wait_for_pid(pid, 0).unwrap();
    let uffd_child = unsafe { Userfaultfd::from_raw_descriptor(uffd_descriptor) };

    let result = unsafe { register_regions(&regions, &[uffd, uffd_child]) };

    // no error from ENOMEM
    assert_eq!(result.is_ok(), true);
}

#[test]
fn unregister_region_skip_obsolete_process() {
    let shm = create_shared_memory("test", 3 * pagesize());
    let uffd = create_uffd_for_test();
    let base_addr = shm.base_addr();
    let regions = [base_addr..(base_addr + 3 * pagesize())];
    let (tube_main, tube_child) = Tube::pair().unwrap();
    let pid = unsafe { libc::fork() };
    if pid == 0 {
        // child process
        let uffd = create_uffd_for_test();
        tube_child
            .send(&unsafe { SafeDescriptor::from_raw_descriptor(uffd.as_raw_descriptor()) })
            .unwrap();
        tube_child.recv::<u8>().unwrap();
        std::process::exit(0);
    }
    let uffd_descriptor = tube_main
        .recv::<SafeDescriptor>()
        .unwrap()
        .into_raw_descriptor();
    let uffd_child = unsafe { Userfaultfd::from_raw_descriptor(uffd_descriptor) };
    let uffds = [uffd, uffd_child];

    unsafe { register_regions(&regions, &uffds) }.unwrap();
    tube_main.send(&0_u8).unwrap();
    // wait until the child process die and the uffd_child become obsolete.
    wait_for_pid(pid, 0).unwrap();
    let result = unregister_regions(&regions, &uffds);

    // no error from ENOMEM
    assert_eq!(result.is_ok(), true);
}