Atmosphere/libraries/libmesosphere/source/kern_k_wait_object.cpp
SciresM 96f95b9f95
Integrate new result macros. (#1780)
* result: try out some experimental shenanigans

* result: sketch out some more shenanigans

* result: see what it looks like to convert kernel to use result conds instead of guards

* make rest of kernel use experimental new macro-ing
2022-02-14 14:45:32 -08:00

103 lines
3.9 KiB
C++

/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <mesosphere.hpp>
namespace ams::kern {
namespace {
class ThreadQueueImplForKWaitObjectSynchronize final : public KThreadQueueWithoutEndWait {
private:
KThread::WaiterList *m_wait_list;
KThread **m_thread;
public:
constexpr ThreadQueueImplForKWaitObjectSynchronize(KThread::WaiterList *wl, KThread **t) : KThreadQueueWithoutEndWait(), m_wait_list(wl), m_thread(t) { /* ... */ }
virtual void CancelWait(KThread *waiting_thread, Result wait_result, bool cancel_timer_task) override {
/* Remove the thread from the wait list. */
m_wait_list->erase(m_wait_list->iterator_to(*waiting_thread));
/* If the result was a timeout and the thread is our wait object thread, cancel recursively. */
if (svc::ResultTimedOut::Includes(wait_result) && waiting_thread == *m_thread) {
for (auto &thread : *m_wait_list) {
thread.CancelWait(svc::ResultTimedOut(), false);
}
}
/* If the thread is our wait object thread, clear it. */
if (*m_thread == waiting_thread) {
*m_thread = nullptr;
}
/* Invoke the base cancel wait handler. */
KThreadQueue::CancelWait(waiting_thread, wait_result, cancel_timer_task);
}
};
}
Result KWaitObject::Synchronize(s64 timeout) {
/* Perform the wait. */
KHardwareTimer *timer;
KThread *cur_thread = GetCurrentThreadPointer();
ThreadQueueImplForKWaitObjectSynchronize wait_queue(std::addressof(m_wait_list), std::addressof(m_next_thread));
{
KScopedSchedulerLockAndSleep slp(std::addressof(timer), cur_thread, timeout);
/* Check that the thread isn't terminating. */
if (cur_thread->IsTerminationRequested()) {
slp.CancelSleep();
R_THROW(svc::ResultTerminationRequested());
}
/* Handle the case where timeout is non-negative/infinite. */
if (timeout >= 0) {
/* Check if we're already waiting. */
if (m_next_thread != nullptr) {
slp.CancelSleep();
R_THROW(svc::ResultBusy());
}
/* If timeout is zero, handle the special case by canceling all waiting threads. */
if (timeout == 0) {
for (auto &thread : m_wait_list) {
thread.CancelWait(svc::ResultTimedOut(), false);
}
slp.CancelSleep();
R_SUCCEED();
}
}
/* If the timeout isn't infinite, register it as our next timeout. */
if (timeout > 0) {
wait_queue.SetHardwareTimer(timer);
m_next_thread = cur_thread;
}
/* Add the current thread to our wait list. */
m_wait_list.push_back(*cur_thread);
/* Wait until the timeout occurs. */
cur_thread->BeginWait(std::addressof(wait_queue));
}
R_SUCCEED();
}
}