#include "config.h"
#include "MainThread.h"
#include "CurrentTime.h"
#include "Deque.h"
#include "StdLibExtras.h"
#include "Threading.h"
#include <mutex>
#include <wtf/Lock.h>
#include <wtf/NeverDestroyed.h>
#include <wtf/ThreadSpecific.h>
namespace WTF {
static bool callbacksPaused; #if !OS(DARWIN) || PLATFORM(EFL) || PLATFORM(GTK)
static ThreadIdentifier mainThreadIdentifier;
#endif
static StaticLock mainThreadFunctionQueueMutex;
static Deque<Function<void ()>>& functionQueue()
{
static NeverDestroyed<Deque<Function<void ()>>> functionQueue;
return functionQueue;
}
#if !OS(DARWIN) || PLATFORM(EFL) || PLATFORM(GTK)
void initializeMainThread()
{
static bool initializedMainThread;
if (initializedMainThread)
return;
initializedMainThread = true;
mainThreadIdentifier = currentThread();
initializeMainThreadPlatform();
initializeGCThreads();
}
#else
static pthread_once_t initializeMainThreadKeyOnce = PTHREAD_ONCE_INIT;
static void initializeMainThreadOnce()
{
initializeMainThreadPlatform();
}
void initializeMainThread()
{
pthread_once(&initializeMainThreadKeyOnce, initializeMainThreadOnce);
}
#if !USE(WEB_THREAD)
static void initializeMainThreadToProcessMainThreadOnce()
{
initializeMainThreadToProcessMainThreadPlatform();
}
void initializeMainThreadToProcessMainThread()
{
pthread_once(&initializeMainThreadKeyOnce, initializeMainThreadToProcessMainThreadOnce);
}
#else
static pthread_once_t initializeWebThreadKeyOnce = PTHREAD_ONCE_INIT;
static void initializeWebThreadOnce()
{
initializeWebThreadPlatform();
}
void initializeWebThread()
{
pthread_once(&initializeWebThreadKeyOnce, initializeWebThreadOnce);
}
#endif // !USE(WEB_THREAD)
#endif
static const auto maxRunLoopSuspensionTime = std::chrono::milliseconds(50);
void dispatchFunctionsFromMainThread()
{
ASSERT(isMainThread());
if (callbacksPaused)
return;
auto startTime = std::chrono::steady_clock::now();
Function<void ()> function;
while (true) {
{
std::lock_guard<StaticLock> lock(mainThreadFunctionQueueMutex);
if (!functionQueue().size())
break;
function = functionQueue().takeFirst();
}
function();
function = nullptr;
if (std::chrono::steady_clock::now() - startTime > maxRunLoopSuspensionTime) {
scheduleDispatchFunctionsOnMainThread();
break;
}
}
}
void callOnMainThread(Function<void ()>&& function)
{
ASSERT(function);
bool needToSchedule = false;
{
std::lock_guard<StaticLock> lock(mainThreadFunctionQueueMutex);
needToSchedule = functionQueue().size() == 0;
functionQueue().append(WTFMove(function));
}
if (needToSchedule)
scheduleDispatchFunctionsOnMainThread();
}
void setMainThreadCallbacksPaused(bool paused)
{
ASSERT(isMainThread());
if (callbacksPaused == paused)
return;
callbacksPaused = paused;
if (!callbacksPaused)
scheduleDispatchFunctionsOnMainThread();
}
#if !OS(DARWIN) || PLATFORM(EFL) || PLATFORM(GTK)
bool isMainThread()
{
return currentThread() == mainThreadIdentifier;
}
#endif
#if !USE(WEB_THREAD)
bool canAccessThreadLocalDataForThread(ThreadIdentifier threadId)
{
return threadId == currentThread();
}
#endif
static ThreadSpecific<bool>* isGCThread;
void initializeGCThreads()
{
isGCThread = new ThreadSpecific<bool>();
}
void registerGCThread()
{
if (!isGCThread) {
return;
}
**isGCThread = true;
}
bool isMainThreadOrGCThread()
{
if (isGCThread->isSet() && **isGCThread)
return true;
return isMainThread();
}
}