Qutex: currOwner should use registered sh_ptr to Lockvoker

This ensures that the Lockvoker object we access from currOwner
remains valid past the lifetime of the Lockvoker object that
gets copied and invoked by boost::asio

include/asynchronousContinuation.h

@@ -68,7 +68,7 @@ public:
 
 	// Implement the virtual method from AsynchronousContinuationChainLink
 	virtual std::shared_ptr<AsynchronousContinuationChainLink>
-	getCallersContinuation() override
+	getCallersContinuationShPtr() override
 		{ return originalCallback.callerContinuation; }
 
 public:

include/asynchronousContinuationChainLink.h

@@ -20,7 +20,7 @@ public:
     virtual ~AsynchronousContinuationChainLink() = default;
 
 	virtual std::shared_ptr<AsynchronousContinuationChainLink>
-	getCallersContinuation() = 0;
+	getCallersContinuationShPtr() = 0;
 };
 
 } // namespace smo

include/lockerAndInvokerBase.h

@@ -37,7 +37,7 @@ public:
 	 * @param qutex The Qutex to get the iterator for
 	 * @return Iterator pointing to this lockvoker in the Qutex's queue
 	 */
-	virtual List::iterator getLockvokerIteratorForQutex(Qutex& qutex) = 0;
+	virtual List::iterator getLockvokerIteratorForQutex(Qutex& qutex) const = 0;
 
 	/**
 	 * @brief Awaken this lockvoker by posting it to its io_service

include/qutex.h

@@ -90,13 +90,14 @@ public:
 	void release();
 
 #ifdef CONFIG_ENABLE_DEBUG_LOCKS
-	LockerAndInvokerBase* getCurrOwner() const { return currOwner; }
+	std::shared_ptr<LockerAndInvokerBase> getCurrOwner() const
+		{ return currOwner; }
 #endif
 
 public:
 #ifdef CONFIG_ENABLE_DEBUG_LOCKS
 	std::string name;
-	LockerAndInvokerBase* currOwner;
+	std::shared_ptr<LockerAndInvokerBase> currOwner;
 #endif
 	SpinLock lock;
 	LockerAndInvokerBase::List queue;

include/serializedAsynchronousContinuation.h

@@ -154,7 +154,7 @@ public:
 		 * @return Iterator pointing to this lockvoker in the Qutex's queue
 		 */
 		LockerAndInvokerBase::List::iterator
-		getLockvokerIteratorForQutex(Qutex& qutex) override
+		getLockvokerIteratorForQutex(Qutex& qutex) const override
 		{
 			return serializedContinuation.requiredLocks.getLockUsageDesc(
 				qutex).second;

smocore/qutex.cpp

@@ -44,7 +44,9 @@ bool Qutex::tryAcquire(
 	{
 		isOwned = true;
 #ifdef CONFIG_ENABLE_DEBUG_LOCKS
-		currOwner = const_cast<LockerAndInvokerBase*>(&tryingLockvoker);
+		// Use the stored iterator from the LockSet
+		auto it = tryingLockvoker.getLockvokerIteratorForQutex(*this);
+		currOwner = *it;
 #endif
 		lock.release();
 		return true;
@@ -59,7 +61,7 @@ bool Qutex::tryAcquire(
 		{
 			isOwned = true;
 #ifdef CONFIG_ENABLE_DEBUG_LOCKS
-			currOwner = const_cast<LockerAndInvokerBase*>(&tryingLockvoker);
+			currOwner = queue.front();
 #endif
 			ret = true;
 		}
@@ -96,7 +98,9 @@ bool Qutex::tryAcquire(
 	// Not found in rear portion - must be in top X%, so succeed
 	isOwned = true;
 #ifdef CONFIG_ENABLE_DEBUG_LOCKS
-	currOwner = const_cast<LockerAndInvokerBase*>(&tryingLockvoker);
+	// Use the stored iterator from the LockSet
+	auto it = tryingLockvoker.getLockvokerIteratorForQutex(*this);
+	currOwner = *it;
 #endif
 	lock.release();
 	return true;

smocore/serializedAsynchronousContinuation.cpp

@@ -27,9 +27,9 @@ SerializedAsynchronousContinuation<OriginalCbFnT>
 	 * lockvoker.
 	 */
 	for (std::shared_ptr<AsynchronousContinuationChainLink> currContin =
-			this->serializedContinuation.getCallersContinuation();
+			this->serializedContinuation.getCallersContinuationShPtr();
 		 currContin != nullptr;
-		 currContin = currContin->getCallersContinuation())
+		 currContin = currContin->getCallersContinuationShPtr())
 	{
 		auto serializedCont = std::dynamic_pointer_cast<
 			SerializedAsynchronousContinuation<OriginalCbFnT>>(currContin);
@@ -94,13 +94,14 @@ SerializedAsynchronousContinuation<OriginalCbFnT>
 	 * Hence, we have a gridlock.
 	 */
 
-	LockerAndInvokerBase* foreignOwnerPtr = firstFailedQutex.getCurrOwner();
+	std::shared_ptr<LockerAndInvokerBase> foreignOwnerShPtr =
+		firstFailedQutex.getCurrOwner();
 	// If no current owner, can't be a gridlock
-	if (foreignOwnerPtr == nullptr)
+	if (foreignOwnerShPtr == nullptr)
 		{ return false; }
 
 	// Use reference for the rest of the function for safety.
-	LockerAndInvokerBase& foreignOwner = *foreignOwnerPtr;
+	LockerAndInvokerBase &foreignOwner = *foreignOwnerShPtr;
 
 	/* For each lock in the foreign owner's LockSet, check if we hold it
 	 * in any of our previous continuations (excluding our most immediate one)
@@ -128,9 +129,9 @@ SerializedAsynchronousContinuation<OriginalCbFnT>
 		 * should eventually be able to acquire that lock.
 		 */
 		for (std::shared_ptr<AsynchronousContinuationChainLink> currContin =
-				this->serializedContinuation.getCallersContinuation();
+				this->serializedContinuation.getCallersContinuationShPtr();
 			 currContin != nullptr;
-			 currContin = currContin->getCallersContinuation())
+			 currContin = currContin->getCallersContinuationShPtr())
 		{
 			auto serializedCont = std::dynamic_pointer_cast<
 				SerializedAsynchronousContinuation<OriginalCbFnT>>(currContin);