Atmosphere/libraries/libstratosphere/source/os/os_semaphore.cpp
Michael Scire 0105455086 git subrepo clone https://github.com/Atmosphere-NX/Atmosphere-libs libraries
subrepo:
  subdir:   "libraries"
  merged:   "07af583b"
upstream:
  origin:   "https://github.com/Atmosphere-NX/Atmosphere-libs"
  branch:   "master"
  commit:   "07af583b"
git-subrepo:
  version:  "0.4.0"
  origin:   "https://github.com/ingydotnet/git-subrepo"
  commit:   "5d6aba9"
2019-12-09 18:54:29 -08:00

86 lines
2.2 KiB
C++

/*
* Copyright (c) 2018-2019 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 "impl/os_waitable_object_list.hpp"
namespace ams::os {
Semaphore::Semaphore(int c, int mc) : count(c), max_count(mc) {
new (GetPointer(this->waitlist)) impl::WaitableObjectList();
}
Semaphore::~Semaphore() {
GetReference(this->waitlist).~WaitableObjectList();
}
void Semaphore::Acquire() {
std::scoped_lock lk(this->mutex);
while (this->count == 0) {
this->condvar.Wait(&this->mutex);
}
this->count--;
}
bool Semaphore::TryAcquire() {
std::scoped_lock lk(this->mutex);
if (this->count == 0) {
return false;
}
this->count--;
return true;
}
bool Semaphore::TimedAcquire(u64 timeout) {
std::scoped_lock lk(this->mutex);
TimeoutHelper timeout_helper(timeout);
while (this->count == 0) {
if (timeout_helper.TimedOut()) {
return false;
}
this->condvar.TimedWait(&this->mutex, timeout_helper.NsUntilTimeout());
}
this->count--;
return true;
}
void Semaphore::Release() {
std::scoped_lock lk(this->mutex);
AMS_ASSERT(this->count + 1 <= this->max_count);
this->count++;
this->condvar.Signal();
GetReference(this->waitlist).SignalAllThreads();
}
void Semaphore::Release(int count) {
std::scoped_lock lk(this->mutex);
AMS_ASSERT(this->count + count <= this->max_count);
this->count += count;
this->condvar.Broadcast();
GetReference(this->waitlist).SignalAllThreads();
}
}