1 files changed, 95 insertions, 0 deletions
diff --git a/profiling/client/src/ProfilingStateMachine.cpp b/profiling/client/src/ProfilingStateMachine.cpp
new file mode 100644
index 0000000000..e002c052b9
--- /dev/null
+++ b/profiling/client/src/ProfilingStateMachine.cpp
@@ -0,0 +1,95 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include "ProfilingStateMachine.hpp"
+
+#include <common/include/ProfilingException.hpp>
+
+#include <sstream>
+
+namespace arm
+{
+
+namespace pipe
+{
+
+namespace
+{
+
+void ThrowStateTransitionException(ProfilingState expectedState, ProfilingState newState)
+{
+    std::stringstream ss;
+    ss << "Cannot transition from state [" << GetProfilingStateName(expectedState) << "] "
+       << "to state [" << GetProfilingStateName(newState) << "]";
+    throw arm::pipe::ProfilingException(ss.str());
+}
+
+} // Anonymous namespace
+
+ProfilingState ProfilingStateMachine::GetCurrentState() const
+{
+    return m_State.load();
+}
+
+void ProfilingStateMachine::TransitionToState(ProfilingState newState)
+{
+    ProfilingState currentState = m_State.load(std::memory_order::memory_order_relaxed);
+
+    switch (newState)
+    {
+    case ProfilingState::Uninitialised:
+        do
+        {
+            if (!IsOneOfStates(currentState, ProfilingState::Uninitialised))
+            {
+                ThrowStateTransitionException(currentState, newState);
+            }
+        }
+        while (!m_State.compare_exchange_strong(currentState, newState, std::memory_order::memory_order_relaxed));
+        break;
+    case  ProfilingState::NotConnected:
+        do
+        {
+            if (!IsOneOfStates(currentState, ProfilingState::Uninitialised, ProfilingState::NotConnected,
+                               ProfilingState::Active, ProfilingState::WaitingForAck))
+            {
+                ThrowStateTransitionException(currentState, newState);
+            }
+        }
+        while (!m_State.compare_exchange_strong(currentState, newState, std::memory_order::memory_order_relaxed));
+        break;
+    case ProfilingState::WaitingForAck:
+        do
+        {
+            if (!IsOneOfStates(currentState, ProfilingState::NotConnected, ProfilingState::WaitingForAck))
+            {
+                ThrowStateTransitionException(currentState, newState);
+            }
+        }
+        while (!m_State.compare_exchange_strong(currentState, newState, std::memory_order::memory_order_relaxed));
+        break;
+    case ProfilingState::Active:
+        do
+        {
+            if (!IsOneOfStates(currentState, ProfilingState::WaitingForAck, ProfilingState::Active))
+            {
+                ThrowStateTransitionException(currentState, newState);
+            }
+        }
+        while (!m_State.compare_exchange_strong(currentState, newState, std::memory_order::memory_order_relaxed));
+        break;
+    default:
+        break;
+    }
+}
+
+void ProfilingStateMachine::Reset()
+{
+    m_State.store(ProfilingState::Uninitialised);
+}
+
+} // namespace pipe
+
+} // namespace arm