//
// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
//
//
// ProfDetach.h
// 

//
// Declaration of helper classes and structures used for Profiling API Detaching
//
// ======================================================================================

#ifndef __PROFDETACH_H__
#define __PROFDETACH_H__

#ifdef FEATURE_PROFAPI_ATTACH_DETACH

// The struct below is the medium by which RequestProfilerDetach communicates with 
// the DetachThread about a profiler being detached.  Initial core attach / 
// detach feature crew will have only one global instance of this struct. 
// When we allow re-attach with neutered profilers, there will likely be a 
// linked list of these, one per profiler in the act of being detached.
struct ProfilerDetachInfo
{
    ProfilerDetachInfo();
    void Init();

    // NULL if we're not trying to detach a profiler.  Otherwise, this is the
    // EEToProfInterfaceImpl instance we're detaching.
    // 
    // FUTURE: Although m_pEEToProf, when non-NULL, is always the same as
    // g_profControlBlock.pProfInterface, that will no longer be the case once we allow
    // re-attach with neutered profilers.
    EEToProfInterfaceImpl * m_pEEToProf;

    // Time when profiler originally called RequestProfilerDetach()
    ULONGLONG               m_ui64DetachStartTime;

    // # milliseconds hint profiler specified in RequestProfilerDetach()
    DWORD                   m_dwExpectedCompletionMilliseconds;
};

//--------------------------------------------------------------------------
// Static-only class to coordinate initialization of the various profiling 
// API detaching structures, plus other utility stuff.
//
class ProfilingAPIDetach
{
public:
    static HRESULT Initialize();

    static HRESULT RequestProfilerDetach(DWORD dwExpectedCompletionMilliseconds);

    static HRESULT CreateDetachThread();
    static DWORD WINAPI ProfilingAPIDetachThreadStart(LPVOID lpParameter);
    static void ExecuteEvacuationLoop();
    static BOOL IsProfilerEvacuated();

    static EEToProfInterfaceImpl * GetEEToProfPtr();

private:
    static ProfilerDetachInfo s_profilerDetachInfo;

    // Signaled by RequestProfilerDetach() when there is detach work ready to be 
    // done by the DetachThread
    static CLREvent           s_eventDetachWorkAvailable;

    static void SleepWhileProfilerEvacuates();
    static void UnloadProfiler();

    // Prevent instantiation of ProfilingAPIDetach objects (should be static-only)
    ProfilingAPIDetach();
    ~ProfilingAPIDetach();
};

#endif // FEATURE_PROFAPI_ATTACH_DETACH

#endif //__PROFDETACH_H__