ladybird/Kernel/Syscalls/waitid.cpp
Andreas Kling 11eee67b85 Kernel: Make self-contained locking smart pointers their own classes
Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:

- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable

This patch renames the Kernel classes so that they can coexist with
the original AK classes:

- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable

The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.
2022-08-20 17:20:43 +02:00

62 lines
1.9 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Variant.h>
#include <Kernel/Debug.h>
#include <Kernel/Process.h>
namespace Kernel {
ErrorOr<siginfo_t> Process::do_waitid(Variant<Empty, NonnullLockRefPtr<Process>, NonnullLockRefPtr<ProcessGroup>> waitee, int options)
{
ErrorOr<siginfo_t> result = siginfo_t {};
if (Thread::current()->block<Thread::WaitBlocker>({}, options, move(waitee), result).was_interrupted())
return EINTR;
VERIFY(!result.is_error() || (options & WNOHANG));
return result;
}
ErrorOr<FlatPtr> Process::sys$waitid(Userspace<Syscall::SC_waitid_params const*> user_params)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
TRY(require_promise(Pledge::proc));
auto params = TRY(copy_typed_from_user(user_params));
Variant<Empty, NonnullLockRefPtr<Process>, NonnullLockRefPtr<ProcessGroup>> waitee;
switch (params.idtype) {
case P_ALL:
break;
case P_PID: {
auto waitee_process = Process::from_pid(params.id);
if (!waitee_process)
return ECHILD;
bool waitee_is_child = waitee_process->ppid() == Process::current().pid();
bool waitee_is_our_tracee = waitee_process->has_tracee_thread(Process::current().pid());
if (!waitee_is_child && !waitee_is_our_tracee)
return ECHILD;
waitee = waitee_process.release_nonnull();
break;
}
case P_PGID: {
auto waitee_group = ProcessGroup::from_pgid(params.id);
if (!waitee_group) {
return ECHILD;
}
waitee = waitee_group.release_nonnull();
break;
}
default:
return EINVAL;
}
dbgln_if(PROCESS_DEBUG, "sys$waitid({}, {}, {}, {})", params.idtype, params.id, params.infop, params.options);
auto siginfo = TRY(do_waitid(move(waitee), params.options));
TRY(copy_to_user(params.infop, &siginfo));
return 0;
}
}