// Copyright (c) 1998-2010 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the License "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// e32\nkern\win32\ncthrd.cpp

//

//

// NThreadBase member data

#define __INCLUDE_NTHREADBASE_DEFINES__

#include "nk_priv.h"

#include <emulator.h>

#if		defined(__CW32__) && defined(__MWERKS__) && (__MWERKS__ < 0x3200)

// Early versions didn't support try/except :(

#error	"This compiler is no longer supported, because it doesn't provide C++ exception generation and handling"

#endif

extern "C" void ExcFault(TAny*);

// initial Win32 thread stack size

const TInt KInitialStackSize = 0x1000;

// maximum size of the parameter block passed to a new thread

const TInt KMaxParameterBlock = 512;

// data passed to new thread to enable hand-off of the parameter block

struct SCreateThread

	{

	const SNThreadCreateInfo* iInfo;

	NFastMutex iHandoff;

	};

/** Set some global properties of the emulator

	Called by the Win32 base port during boot.

	@param	aTrace TRUE means trace Win32 thread ID for every thread created

	@param	aSingleCpu TRUE means lock the emulator process to a single CPU

	@internalTechnology

 */

EXPORT_C void NThread::SetProperties(TBool aTrace, TInt aSingleCpu)

	{

	Win32TraceThreadId = aTrace;

	Win32SingleCpu = aSingleCpu;

	}

void NThread__HandleException(TWin32ExcInfo aExc)

//

// Final stage NKern exception handler.

//

// The first stage of exception processing (in ExceptionHandler()) entered the

// kernel and locked it, so we have to undo those two operations before returning.

// However, if the kernel was already locked when the exception occurred, it is

// a fatal condition and the system will be faulted.

//

// Note that the parameter struct is passed by value, this allows for direct

// access to the exception context created on the call stack by NThread::Exception().

//

	{

	NKern::Unlock();

	if (TheScheduler.iKernCSLocked)

		ExcFault(&aExc);

	// Complete the exception data. Note that the call to EnterKernel() in

	// ExceptionHandler() will have incremented iInKernel after the exception

	// occurred.

	NThread* me = static_cast<NThread*>(TheScheduler.iCurrentThread);

	__NK_ASSERT_DEBUG(me->iInKernel);

	aExc.iFlags = me->iInKernel == 1 ? 0 : TWin32ExcInfo::EExcInKernel;

	aExc.iHandler = NULL;

	// run NThread exception handler in 'kernel' mode

	me->iHandlers->iExceptionHandler(&aExc, me);

	LeaveKernel();

	// If a 'user' handler is set by the kernel handler, run it

	if (aExc.iHandler)

		aExc.iHandler(aExc.iParam[0], aExc.iParam[1]);

	}

__NAKED__ void NThread::Exception()

//

// Trampoline to nKern exception handler

// Must preserve all registers in the structure defined by TWin32Exc

//

// This is an intermediate layer, to which control has been diverted by

// NThread::ExceptionHandler(). It constructs a TWin32Exc structure on

// the stack and passes it NThread__ExceptionHandler().

//

// At this point we are no longer in Win32 exception context.

//

	{

	// this is the TWin32Exc structure

	__asm push Win32ExcAddress			// save return address followed by EBP first to help debugger

	__asm push ebp

	__asm mov ebp, esp

	__asm push cs

	__asm pushfd

	__asm push gs

	__asm push fs

	__asm push es

	__asm push ds

	__asm push ss

	__asm push edi

	__asm push esi

	__asm lea esi, [ebp+8]

	__asm push esi						// original esp

	__asm push ebx

	__asm push edx

	__asm push ecx

	__asm push eax

	__asm push Win32ExcDataAddress

	__asm push Win32ExcCode

	__asm sub esp, 20					// struct init completed by NThread__HandleException()

	__asm call NThread__HandleException

	__asm add esp, 28

	__asm pop eax

	__asm pop ecx

	__asm pop edx

	__asm pop ebx

	__asm pop esi						// original ESP - ignore

	__asm pop esi

	__asm pop edi

	__asm pop ebp						// original SS - ignore

	__asm pop ds

	__asm pop es

	__asm pop fs

	__asm pop gs

	__asm popfd

	__asm pop ebp						// original CS - ignore

	__asm pop ebp

	__asm ret

	}

// From e32/commmon/win32/seh.cpp

extern DWORD CallFinalSEHHandler(EXCEPTION_RECORD* aException, CONTEXT* aContext);

extern void DivertHook();

DWORD NThread::ExceptionHandler(EXCEPTION_RECORD* aException, CONTEXT* aContext)

//

// Win32 exception handler for EPOC threads

//

// This is the outermost wrapper, called from ExceptionFilter() of via manual

// interception of the Win32 exception mechanism if using a really old compiler

//

	{

	if (aException->ExceptionCode == EXCEPTION_BREAKPOINT)

		{

		// Hardcoded breakpoint

		//

		// Jump directly to NT's default unhandled exception handler which will

		// either display a dialog, directly invoke the JIT debugger or do nothing

		// dependent upon the AeDebug and ErrorMode registry settings.

		//

		// Note this handler is always installed on the SEH chain and is always

		// the last handler on this chain, as it is installed by NT in kernel32.dll

		// before invoking the Win32 thread function.

		return CallFinalSEHHandler(aException, aContext);

		}

	// deal with conflict between preemption and diversion

	// the diversion will have been applied to the pre-exception context, not

	// the current context, and thus will get 'lost'. Wake-up of a pre-empted

	// thread with a diversion will not unlock the kernel, so we need to deal

	// with the possibility that the kernel may be locked if a diversion exists

	NThread& me = *static_cast<NThread*>(TheScheduler.iCurrentThread);

	if (me.iDiverting && me.iDivertFn)

		{

		// The thread is being forced to exit - run the diversion outside of Win32 exception handler

		__NK_ASSERT_ALWAYS(TheScheduler.iKernCSLocked == 1);

		aContext->Eip = (TUint32)&DivertHook;

		}

	else

		{

		if (me.iDiverting)

			{

			// The thread is being prodded to pick up its callbacks.  This will happen when the

			// exception handler calls LeaveKernel(), so we can remove the diversion

			__NK_ASSERT_ALWAYS(TheScheduler.iKernCSLocked == 1);

			if (aException->ExceptionAddress == &DivertHook)

				aException->ExceptionAddress = me.iDivertReturn;

			me.iDivertReturn = NULL;

			me.iDiverting = EFalse;

			EnterKernel(TRUE);

			}

		else

			{

			EnterKernel();

			TheScheduler.iKernCSLocked = 1;	// prevent pre-emption

			}

		// If the kernel was already locked, this will be detected in the next stage handler

		// (NThread::Exception()), which we arrange to run outside the Win32 exception context

		Win32ExcAddress = aException->ExceptionAddress;

		Win32ExcDataAddress = (TAny*)aException->ExceptionInformation[1];

		Win32ExcCode = aException->ExceptionCode;

		aContext->Eip = (TUint32)&Exception;

		}

	return ExceptionContinueExecution;

	}

LONG WINAPI NThread::ExceptionFilter(EXCEPTION_POINTERS* aExc)

//

// Filter wrapper for main Win32 exception handler

//

	{

	LONG ret = EXCEPTION_CONTINUE_SEARCH;

	switch (ExceptionHandler(aExc->ExceptionRecord, aExc->ContextRecord))

		{

	case ExceptionContinueExecution:

		ret = EXCEPTION_CONTINUE_EXECUTION;

		break;

	case ExceptionContinueSearch:

	default:

		break;

		}

	return ret;

	}

DWORD WINAPI NThread::StartThread(LPVOID aParam)

//

// Win32 thread function for nKern threads.

//

// The thread first enters this function after the nScheduler has resumed

// it, following the context switch induced by the hand-off mutex.

//

// The parameter block for this thread needs to be copied into its

// own context, before releasing the mutex and handing control back to

// the creating thread.

//

	{

	SCreateThread* init = static_cast<SCreateThread*>(aParam);

	NThread& me = *static_cast<NThread*>(init->iHandoff.iHoldingThread);

	me.iWinThreadId = GetCurrentThreadId();

	SchedulerRegister(me);

#ifdef BTRACE_FAST_MUTEX

	BTraceContext4(BTrace::EFastMutex, BTrace::EFastMutexWait, &init->iHandoff);

#endif

	NKern::Unlock();

	// intercept win32 exceptions in a debuggabble way

	__try

		{

		// save the thread entry point and parameter block

		const SNThreadCreateInfo& info = *init->iInfo;

		NThreadFunction threadFunction = info.iFunction;

		TUint8 parameterBlock[KMaxParameterBlock];

		TAny* parameter = (TAny*)info.iParameterBlock;

		if (info.iParameterBlockSize)

			{

			__NK_ASSERT_DEBUG(TUint(info.iParameterBlockSize) <= TUint(KMaxParameterBlock));

			memcpy(parameterBlock, info.iParameterBlock, info.iParameterBlockSize);

			parameter = parameterBlock;

			}

		// Calculate stack base

		me.iUserStackBase = (((TLinAddr)&parameterBlock) + 0xfff) & ~0xfff;

		// some useful diagnostics for debugging

		if (Win32TraceThreadId)

			KPrintf("Thread %T created @ 0x%x - Win32 Thread ID 0x%x", init->iHandoff.iHoldingThread, init->iHandoff.iHoldingThread, GetCurrentThreadId());

#ifdef MONITOR_THREAD_CPU_TIME

		me.iLastStartTime = 0;  // Don't count NThread setup in cpu time

#endif

		// start-up complete, release the handoff mutex, which will re-suspend us

		NKern::FMSignal(&init->iHandoff);

		// thread has been resumed: invoke the thread function

		threadFunction(parameter);

		}

	__except (ExceptionFilter(GetExceptionInformation()))

		{

		// Do nothing - filter does all the work and hooks into EPOC

		// h/w exception mechanism if necessary by thread diversion

		}

	NKern::Exit();

	return 0;

	}

/**

 * Set the Win32 thread priority based on the thread type.

 * Interrupt/Event threads must be able to preempt normal

 * nKern threads, so they get a higher (Win32) priority.

 */

static void SetPriority(HANDLE aThread, TEmulThreadType aType)

	{

	TInt p;

	switch (aType)

		{

	default:

		FAULT();

	case EThreadEvent:

		p = THREAD_PRIORITY_ABOVE_NORMAL;

		break;

	case EThreadNKern:

		p = THREAD_PRIORITY_NORMAL;

		break;

		}

	CheckedSetThreadPriority(aThread, p);

	SetThreadPriorityBoost(aThread, TRUE);		// disable priority boost (for NT)

	}

/**	Create a Win32 thread for use in the emulator.

	@param	aType Type of thread (Event or NKern) - determines Win32 priority

	@param	aThreadFunc Entry point of thread

	@param	aPtr Argument passed to entry point

	@param	aRun TRUE if thread should be resumed immediately

	@return	The Win32 handle to the thread, 0 if an error occurred

	@pre    Call either in thread context.

	@pre	Do not call from bare Win32 threads.

	@see TEmulThreadType

 */

EXPORT_C HANDLE CreateWin32Thread(TEmulThreadType aType, LPTHREAD_START_ROUTINE aThreadFunc, LPVOID aPtr, TBool aRun)

	{

	__NK_ASSERT_DEBUG(!TheScheduler.iCurrentThread || NKern::CurrentContext() == NKern::EThread);

	__LOCK_HOST;

	DWORD id;

	HANDLE handle = CreateThread(NULL , KInitialStackSize, aThreadFunc, aPtr, CREATE_SUSPENDED, &id);

	if (handle)

		{

		SetPriority(handle, aType);

		if (aRun)

			ResumeThread(handle);

		}

	return handle;

	}

static HANDLE InitThread()

//

// Set up the initial thread and return the thread handle

//

	{

	HANDLE p = GetCurrentProcess();

	HANDLE me;

	DWORD r = DuplicateHandle(p, GetCurrentThread(), p, &me, 0, FALSE, DUPLICATE_SAME_ACCESS);

	__NK_ASSERT_ALWAYS(r != 0);						// r is zero on error

	SetPriority(me, EThreadNKern);

	return me;

	}

TInt NThread::Create(SNThreadCreateInfo& aInfo, TBool aInitial)

	{

	iWinThread = NULL;

	iWinThreadId = 0;

	iScheduleLock = NULL;

	iInKernel = 1;

	iDivertFn = NULL;

	iWakeup = aInitial ? ERelease : EResumeLocked;	// mark new threads as created (=> win32 suspend)

	TInt r = NThreadBase::Create(aInfo, aInitial);

	if (r != KErrNone)

		return r;

	// the rest has to be all or nothing, we must complete it

	iScheduleLock = CreateEventA(NULL, FALSE, FALSE, NULL);

	if (iScheduleLock == NULL)

		return Emulator::LastError();

	if (aInitial)

		{

		iWinThread = InitThread();

		FastCounterInit();

#ifdef MONITOR_THREAD_CPU_TIME

		iLastStartTime = NKern::FastCounter();

#endif

		iUserStackBase = (((TLinAddr)&r) + 0xfff) & ~0xfff; // base address of stack

		SchedulerInit(*this);

		return KErrNone;

		}

	// create the thread proper

	//

	SCreateThread start;

	start.iInfo = &aInfo;

	iWinThread = CreateWin32Thread(EThreadNKern, &StartThread, &start, FALSE);

	if (iWinThread == NULL)

		{

		r = Emulator::LastError();

		CloseHandle(iScheduleLock);

		return r;

		}

#ifdef BTRACE_THREAD_IDENTIFICATION

	BTrace4(BTrace::EThreadIdentification, BTrace::ENanoThreadCreate, this);

#endif

	// switch to the new thread to hand over the parameter block

	NKern::Lock();

	ForceResume();	// mark the thread as ready

	// give the thread ownership of the handoff mutex

	start.iHandoff.iHoldingThread = this;

	iHeldFastMutex = &start.iHandoff;

	Suspend(1);		// will defer as holding a fast mutex (implicit critical section)

	// do the hand-over

	start.iHandoff.Wait();

	start.iHandoff.Signal();

	NKern::Unlock();

	return KErrNone;

	}

void NThread::Diverted()

//

// This function is called in the context of a thread that is being diverted.

// This can be for either of two reasons: if iDivertFn has been set, that

// function will be called and is not expected to return i.e.  it should force

// the thread to exit (in this case, the thread may already be in the kernel,

// but only at a place where it's safe for it to be killed).  Otherwise, the

// thread must be in user mode, and it's forced to make a null trip through

// the kernel, causing it to run pending user-mode callbacks on the way out.

//

// On entry, the kernel is locked and interrupts enabled

//

	{

	NThread& me = *static_cast<NThread*>(TheScheduler.iCurrentThread);

	__NK_ASSERT_ALWAYS(TheScheduler.iKernCSLocked == 1);

	__NK_ASSERT_ALWAYS(me.iDiverting);

	NThread::TDivert divertFn = me.iDivertFn;

	me.iDivertFn = NULL;

	me.iDivertReturn = NULL;

	me.iDiverting = EFalse;

	EnterKernel(TRUE);

	if (divertFn)

		divertFn();					// does not return

	NKern::Unlock();

	LeaveKernel();

	}

void NThread__Diverted()

	{

	NThread::Diverted();

	}

__NAKED__ void DivertHook()

	{

	// The stack frame is set up like this:

	//

	//		| return address |

	//		| frame pointer  |

	//		| flags			 |

	//		| saved eax		 |

	//		| saved ecx		 |

	//      | saved edx		 |

	//

	__asm push eax					// reserve word for return address

	__asm push ebp

	__asm mov ebp, esp

	__asm pushfd

	__asm push eax

	__asm push ecx

	__asm push edx

	__asm mov eax, [TheScheduler.iCurrentThread]

	__asm mov eax, [eax]NThread.iDivertReturn

	__asm mov [esp + 20], eax		// store return address

	__asm call NThread__Diverted

	__asm pop edx

	__asm pop ecx

	__asm pop eax

	__asm popfd

	__asm pop ebp

	__asm ret

	}