// throws on context depth level overflows and cross-context cycles
void c_WaitableWaitHandle::join() {
JIT::EagerVMRegAnchor _;
AsioSession* session = AsioSession::Get();
assert(!isFinished());
assert(!session->isInContext() || session->getCurrentContext()->isRunning());
if (UNLIKELY(session->hasOnJoinCallback())) {
session->onJoin(this);
}
// enter new asio context and set up guard that will exit once we are done
session->enterContext();
auto exit_guard = folly::makeGuard([&] { session->exitContext(); });
assert(session->isInContext());
assert(!session->getCurrentContext()->isRunning());
// import this wait handle to the newly created context
// throws if cross-context cycle found
enterContext(session->getCurrentContextIdx());
// run queues until we are finished
session->getCurrentContext()->runUntil(this);
assert(isFinished());
}
// throws on context depth level overflows and cross-context cycles
void c_WaitableWaitHandle::join() {
AsioSession* session = AsioSession::Get();
assert(!isFinished());
assert(!session->isInContext() || session->getCurrentContext()->isRunning());
if (UNLIKELY(session->hasOnJoinCallback())) {
session->onJoin(this);
}
// enter new asio context and set up guard that will exit once we are done
session->enterContext();
assert(session->isInContext());
assert(!session->getCurrentContext()->isRunning());
try {
// import this wait handle to the newly created context
// throws if cross-context cycle found
enterContext(session->getCurrentContextIdx());
// run queues until we are finished
session->getCurrentContext()->runUntil(this);
} catch (const Object& exception) {
// recover from PHP exceptions; HPHP internal exceptions are deliberately
// ignored as there is no easy way to recover from them
session->exitContext();
throw;
}
session->exitContext();
assert(isFinished());
}
void c_AsyncFunctionWaitHandle::Create(c_Continuation* continuation) {
assert(continuation);
assert(continuation->m_label > 0);
assert(continuation->m_waitHandle.isNull());
AsioSession* session = AsioSession::Get();
uint16_t depth = session->getCurrentWaitHandleDepth();
if (UNLIKELY(depth >= MAX_DEPTH)) {
Object e(SystemLib::AllocInvalidOperationExceptionObject(
"Asio stack overflow"));
throw e;
}
Cell* value = tvAssertCell(continuation->m_value.asTypedValue());
assert(dynamic_cast<c_WaitableWaitHandle*>(c_WaitHandle::fromCell(value)));
auto child = static_cast<c_WaitableWaitHandle*>(value->m_data.pobj);
assert(!child->isFinished());
// import child into the current context, detect cross-context cycles
if (session->isInContext()) {
child->enterContext(session->getCurrentContextIdx());
}
continuation->m_waitHandle = NEWOBJ(c_AsyncFunctionWaitHandle)();
continuation->m_waitHandle->initialize(continuation, child, depth + 1);
// needs to be called after continuation->m_waitHandle is set
if (UNLIKELY(session->hasOnAsyncFunctionCreateCallback())) {
session->onAsyncFunctionCreate(continuation->m_waitHandle.get());
}
}
Object c_ContinuationWaitHandle::ti_start(const char* cls, CObjRef continuation) {
AsioSession* session = AsioSession::Get();
if (UNLIKELY(!continuation.instanceof(SystemLib::s_ContinuationClass))) {
Object e(SystemLib::AllocInvalidArgumentExceptionObject(
"Expected continuation to be an instance of Continuation"));
throw e;
}
uint16_t depth = session->getCurrentWaitHandleDepth();
if (UNLIKELY(depth >= MAX_DEPTH)) {
Object e(SystemLib::AllocInvalidOperationExceptionObject(
"Asio stack overflow"));
throw e;
}
c_Continuation* cont = static_cast<c_Continuation*>(continuation.get());
if (!cont->m_waitHandle.isNull()) {
if (session->isInContext()) {
// throws if cross-context cycle found
cont->m_waitHandle->enterContext(session->getCurrentContextIdx());
}
return cont->m_waitHandle;
}
if (UNLIKELY(cont->m_index != -1)) {
assert(cont->m_running);
Object e(SystemLib::AllocInvalidOperationExceptionObject(
"Encountered an attempt to start currently running continuation"));
throw e;
}
p_ContinuationWaitHandle wh = NEWOBJ(c_ContinuationWaitHandle)();
wh->start(cont, depth + 1);
if (UNLIKELY(session->hasOnStartedCallback())) {
session->onStarted(wh);
}
return wh;
}
