#include "config.h"
#include "MainThread.h"
#include "CurrentTime.h"
#include "Deque.h"
#include "StdLibExtras.h"
#include "Threading.h"
#include <wtf/iphone/WebCoreThread.h>
#if PLATFORM(CHROMIUM)
#error Chromium uses a different main thread implementation
#endif
namespace WTF {
struct FunctionWithContext {
MainThreadFunction* function;
void* context;
ThreadCondition* syncFlag;
FunctionWithContext(MainThreadFunction* function = 0, void* context = 0, ThreadCondition* syncFlag = 0)
: function(function)
, context(context)
, syncFlag(syncFlag)
{
}
bool operator == (const FunctionWithContext& o)
{
return function == o.function
&& context == o.context
&& syncFlag == o.syncFlag;
}
};
class FunctionWithContextFinder {
public:
FunctionWithContextFinder(const FunctionWithContext& m) : m(m) {}
bool operator() (FunctionWithContext& o) { return o == m; }
FunctionWithContext m;
};
typedef Deque<FunctionWithContext> FunctionQueue;
static bool callbacksPaused; #if !PLATFORM(MAC) && !PLATFORM(QT)
static ThreadIdentifier mainThreadIdentifier;
#endif
static Mutex& mainThreadFunctionQueueMutex()
{
DEFINE_STATIC_LOCAL(Mutex, staticMutex, ());
return staticMutex;
}
static FunctionQueue& functionQueue()
{
DEFINE_STATIC_LOCAL(FunctionQueue, staticFunctionQueue, ());
return staticFunctionQueue;
}
#if !PLATFORM(MAC)
void initializeMainThread()
{
static bool initializedMainThread;
if (initializedMainThread)
return;
initializedMainThread = true;
#if !PLATFORM(QT)
mainThreadIdentifier = currentThread();
#endif
mainThreadFunctionQueueMutex();
initializeMainThreadPlatform();
}
#else
static pthread_once_t initializeMainThreadKeyOnce = PTHREAD_ONCE_INIT;
static void initializeMainThreadOnce()
{
mainThreadFunctionQueueMutex();
initializeMainThreadPlatform();
}
void initializeMainThread()
{
pthread_once(&initializeMainThreadKeyOnce, initializeMainThreadOnce);
}
static void initializeMainThreadToProcessMainThreadOnce()
{
mainThreadFunctionQueueMutex();
initializeMainThreadToProcessMainThreadPlatform();
}
void initializeMainThreadToProcessMainThread()
{
pthread_once(&initializeMainThreadKeyOnce, initializeMainThreadToProcessMainThreadOnce);
}
#endif
static const double maxRunLoopSuspensionTime = 0.05;
void dispatchFunctionsFromMainThread()
{
ASSERT(isMainThread());
if (callbacksPaused)
return;
double startTime = currentTime();
FunctionWithContext invocation;
while (true) {
{
MutexLocker locker(mainThreadFunctionQueueMutex());
if (!functionQueue().size())
break;
invocation = functionQueue().takeFirst();
}
invocation.function(invocation.context);
if (invocation.syncFlag) {
MutexLocker locker(mainThreadFunctionQueueMutex());
invocation.syncFlag->signal();
}
if (currentTime() - startTime > maxRunLoopSuspensionTime) {
scheduleDispatchFunctionsOnMainThread();
break;
}
}
}
void callOnMainThread(MainThreadFunction* function, void* context)
{
ASSERT(function);
bool needToSchedule = false;
{
MutexLocker locker(mainThreadFunctionQueueMutex());
needToSchedule = functionQueue().size() == 0;
functionQueue().append(FunctionWithContext(function, context));
}
if (needToSchedule)
scheduleDispatchFunctionsOnMainThread();
}
void callOnMainThreadAndWait(MainThreadFunction* function, void* context)
{
ASSERT(function);
if (isMainThread()) {
function(context);
return;
}
ThreadCondition syncFlag;
Mutex& functionQueueMutex = mainThreadFunctionQueueMutex();
MutexLocker locker(functionQueueMutex);
functionQueue().append(FunctionWithContext(function, context, &syncFlag));
if (functionQueue().size() == 1)
scheduleDispatchFunctionsOnMainThread();
syncFlag.wait(functionQueueMutex);
}
void cancelCallOnMainThread(MainThreadFunction* function, void* context)
{
ASSERT(function);
MutexLocker locker(mainThreadFunctionQueueMutex());
FunctionWithContextFinder pred(FunctionWithContext(function, context));
while (true) {
FunctionQueue::iterator i(functionQueue().findIf(pred));
if (i == functionQueue().end())
break;
functionQueue().remove(i);
}
}
void setMainThreadCallbacksPaused(bool paused)
{
ASSERT((isMainThread() || pthread_main_np()) && WebCoreWebThreadIsLockedOrDisabled());
if (callbacksPaused == paused)
return;
callbacksPaused = paused;
if (!callbacksPaused)
scheduleDispatchFunctionsOnMainThread();
}
#if !PLATFORM(MAC) && !PLATFORM(QT) && !PLATFORM(BREWMP)
bool isMainThread()
{
return currentThread() == mainThreadIdentifier;
}
#endif
}