mirror of
https://github.com/kidfromjupiter/nearby.git
synced 2026-09-14 22:56:12 -04:00
91 lines
2.4 KiB
C++
91 lines
2.4 KiB
C++
// Copyright 2021 Google LLC
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// https://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#include "platform/impl/windows/mutex.h"
|
|
|
|
namespace location {
|
|
namespace nearby {
|
|
namespace windows {
|
|
|
|
// A lock is a tool for controlling access to a shared resource by multiple
|
|
// threads.
|
|
//
|
|
// https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/locks/Lock.html
|
|
Mutex::Mutex(Mutex::Mode mode)
|
|
: mode_(mode), owning_thread_(std::this_thread::get_id()) {
|
|
InitializeCriticalSection(&critical_section_);
|
|
}
|
|
|
|
void Mutex::Lock() {
|
|
EnterCriticalSection(&critical_section_);
|
|
|
|
std::thread::id currentThread = std::this_thread::get_id();
|
|
|
|
if ((mode_ == Mutex::Mode::kRegular ||
|
|
mode_ == Mutex::Mode::kRegularNoCheck) &&
|
|
!locked_) {
|
|
mutex_actual_.lock();
|
|
owning_thread_ = currentThread;
|
|
locked_ = true;
|
|
}
|
|
|
|
if (mode_ == Mutex::Mode::kRecursive) {
|
|
if (!locked_) {
|
|
owning_thread_ = currentThread;
|
|
}
|
|
if (owning_thread_ == currentThread) {
|
|
try {
|
|
recursive_mutex_actual_.lock();
|
|
} catch ([[maybe_unused]] const std::system_error& e) {
|
|
// Eat the exception and fail silently, argument left for debug
|
|
}
|
|
locked_ = true;
|
|
}
|
|
}
|
|
|
|
LeaveCriticalSection(&critical_section_);
|
|
}
|
|
|
|
void Mutex::Unlock() {
|
|
EnterCriticalSection(&critical_section_);
|
|
|
|
std::thread::id currentThread = std::this_thread::get_id();
|
|
|
|
if (mode_ == Mutex::Mode::kRegular || mode_ == Mutex::Mode::kRegularNoCheck) {
|
|
if (currentThread == owning_thread_) {
|
|
mutex_actual_.unlock();
|
|
locked_ = false;
|
|
}
|
|
}
|
|
|
|
if (mode_ == Mutex::Mode::kRecursive) {
|
|
if (currentThread == owning_thread_) {
|
|
recursive_mutex_actual_.unlock();
|
|
locked_ = false;
|
|
}
|
|
}
|
|
|
|
LeaveCriticalSection(&critical_section_);
|
|
}
|
|
|
|
std::mutex& Mutex::GetWindowsMutex() { return mutex_; }
|
|
|
|
std::recursive_mutex& Mutex::GetWindowsRecursiveMutex() {
|
|
return recursive_mutex_;
|
|
}
|
|
|
|
} // namespace windows
|
|
} // namespace nearby
|
|
} // namespace location
|