ktmgr.cpp

一本叫自己动手写嵌入式操作系统的书的源代码,作者是蓝枫叶,详细介绍了如何写一个嵌入式操作系统,而不是操作系统

//***********************************************************************/
//    Author                    : Garry
//    Original Date             : Oct,18 2004
//    Module Name               : ktmgr.cpp
//    Module Funciton           : 
//                                This module countains kernel thread and kernel thread 
//                                manager's implementation code.
//
//                                ************
//                                This file is the most important file of Hello China.
//                                ************
//    Last modified Author      : Garry
//    Last modified Date        : Sep,30,2006
//    Last modified Content     :
//                                1. 
//                                2.
//    Lines number              :
//***********************************************************************/

#ifndef __STDAFX_H__
#include "..\INCLUDE\StdAfx.h"
#endif

#include "..\INCLUDE\ARCHSTD.H"

//
//Pre-declare for extern global routines,these routines may
//be implemented in KTMGRx.CPP file,where x is 2,3,etc.
//
extern __THREAD_HOOK_ROUTINE SetThreadHook(DWORD dwHookType,
										   __THREAD_HOOK_ROUTINE lpRoutine);
extern VOID                  CallThreadHook(DWORD dwHookType,
											__KERNEL_THREAD_OBJECT* lpPrev,
											__KERNEL_THREAD_OBJECT* lpNext);
extern __KERNEL_THREAD_OBJECT* GetScheduleKernelThread(__COMMON_OBJECT* lpThis,
													   DWORD dwPriority);
extern VOID AddReadyKernelThread(__COMMON_OBJECT* lpThis,
								 __KERNEL_THREAD_OBJECT* lpKernelThread);
extern VOID KernelThreadWrapper(__COMMON_OBJECT*);
extern DWORD WaitForKernelThreadObject(__COMMON_OBJECT* lpThis);

//
//Static global varaibles.
//

CHAR* lpszCriticalMsg = "CRITICAL ERROR : The internal data structure is not consecutive,\
                         please restart the system!!";

//
//The initialization routine of Kernel Thread Object.
//In the current implementation of Hello China,we do the following task:
// 1. Create the waiting queue object of the kernel thread object;
// 2. Initialize the waiting queue object;
// 3. Set appropriaty value of the member functions,such as WaitForThisObject.
//

BOOL KernelThreadInitialize(__COMMON_OBJECT* lpThis)
{
	BOOL                    bResult           = FALSE;
	__PRIORITY_QUEUE*       lpWaitingQueue    = NULL;
	__KERNEL_THREAD_OBJECT* lpKernelThread    = NULL;
	__PRIORITY_QUEUE*       lpMsgWaitingQueue = NULL;

	if(NULL == lpThis)  //Parameter check.
		goto __TERMINAL;

	lpKernelThread = (__KERNEL_THREAD_OBJECT*)lpThis;
	lpWaitingQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(
		&ObjectManager,
		NULL,
		OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpWaitingQueue)    //Failed to create the waiting queue object.
		goto __TERMINAL;

	if(!lpWaitingQueue->Initialize((__COMMON_OBJECT*)lpWaitingQueue))
	    //Failed to initialize the waiting queue object.
		goto __TERMINAL;
	lpMsgWaitingQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(
		&ObjectManager,
		NULL,
		OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpMsgWaitingQueue)  //Can not create message waiting queue.
		goto __TERMINAL;
	if(!lpMsgWaitingQueue->Initialize((__COMMON_OBJECT*)lpMsgWaitingQueue))
		goto __TERMINAL;

	lpKernelThread->lpWaitingQueue    = lpWaitingQueue;
	lpKernelThread->lpMsgWaitingQueue = lpMsgWaitingQueue;
	lpKernelThread->WaitForThisObject = WaitForKernelThreadObject;
	lpKernelThread->lpKernelThreadContext = NULL;

	bResult = TRUE;

__TERMINAL:
	if(!bResult)        //Initialize failed.
	{
		if(lpWaitingQueue != NULL)
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpWaitingQueue);
		if(lpMsgWaitingQueue != NULL)
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpMsgWaitingQueue);
	}
	return bResult;
}

//
//The Uninitialize routine of kernel thread object.
//

VOID KernelThreadUninitialize(__COMMON_OBJECT* lpThis)
{
	__KERNEL_THREAD_OBJECT*   lpKernelThread = NULL;
	__PRIORITY_QUEUE*         lpWaitingQueue = NULL;
	__EVENT*                  lpMsgEvent     = NULL;

	if(NULL == lpThis)    //Parameter check.
		return;

	lpKernelThread = (__KERNEL_THREAD_OBJECT*)lpThis;
	//Destroy waiting queue.
	ObjectManager.DestroyObject(&ObjectManager,
		(__COMMON_OBJECT*)lpKernelThread->lpWaitingQueue);

	//Destroy message waiting queue.
	ObjectManager.DestroyObject(&ObjectManager,
		(__COMMON_OBJECT*)lpKernelThread->lpMsgWaitingQueue);

	return;
}

//
//The implementation of Kernel Thread Manager.
//

//Initializing routine of Kernel Thread Manager.
static BOOL KernelThreadMgrInit(__COMMON_OBJECT* lpThis)
{
	BOOL                       bResult          = FALSE;
	__KERNEL_THREAD_MANAGER*   lpMgr            = NULL;
	__PRIORITY_QUEUE*          lpRunningQueue   = NULL;
	__PRIORITY_QUEUE*          lpReadyQueue     = NULL;
	__PRIORITY_QUEUE*          lpSuspendedQueue = NULL;
	__PRIORITY_QUEUE*          lpSleepingQueue  = NULL;
	__PRIORITY_QUEUE*          lpTerminalQueue  = NULL;
	DWORD i;

	if(NULL == lpThis)
		return bResult;

	lpMgr = (__KERNEL_THREAD_MANAGER*)lpThis;

	//
	//The following code creates all objects required by Kernel Thread Manager.
	//If any error occurs,the initializing process is terminaled.
	//
	lpRunningQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(&ObjectManager,NULL,OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpRunningQueue)
		goto __TERMINAL;
	if(FALSE == lpRunningQueue->Initialize((__COMMON_OBJECT*)lpRunningQueue))
		goto __TERMINAL;

	lpReadyQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(&ObjectManager,NULL,OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpReadyQueue)
		goto __TERMINAL;
	if(FALSE == lpReadyQueue->Initialize((__COMMON_OBJECT*)lpReadyQueue))
		goto __TERMINAL;

	lpSuspendedQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(&ObjectManager,NULL,OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpSuspendedQueue)
		goto __TERMINAL;
	if(FALSE == lpSuspendedQueue->Initialize((__COMMON_OBJECT*)lpSuspendedQueue))
		goto __TERMINAL;

	lpSleepingQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(&ObjectManager,NULL,OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpSleepingQueue)
		goto __TERMINAL;
	if(FALSE == lpSleepingQueue->Initialize((__COMMON_OBJECT*)lpSleepingQueue))
		goto __TERMINAL;

	lpTerminalQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(&ObjectManager,NULL,OBJECT_TYPE_PRIORITY_QUEUE);
	if(NULL == lpTerminalQueue)
		goto __TERMINAL;
	if(FALSE == lpTerminalQueue->Initialize((__COMMON_OBJECT*)lpTerminalQueue))
		goto __TERMINAL;


	//
	//Now,the objects required by Kernel Thread Manager are created and initialized success-
	//fully,initialize the kernel thread manager itself now.
	//
	lpMgr->lpRunningQueue    = lpRunningQueue;
	//lpMgr->lpReadyQueue      = lpReadyQueue;
	lpMgr->lpSuspendedQueue  = lpSuspendedQueue;
	lpMgr->lpSleepingQueue   = lpSleepingQueue;
	lpMgr->lpTerminalQueue   = lpTerminalQueue;

	//Initializes the ready queue array.Any element failure can cause the whole
	//process to fail.
	for(i = 0;i < MAX_KERNEL_THREAD_PRIORITY + 1;i ++)
	{
		lpReadyQueue = (__PRIORITY_QUEUE*)ObjectManager.CreateObject(&ObjectManager,
			NULL,
			OBJECT_TYPE_PRIORITY_QUEUE);
		if(NULL == lpReadyQueue)
		{
			goto __TERMINAL;
		}
		if(!lpReadyQueue->Initialize((__COMMON_OBJECT*)lpReadyQueue))  //Can not initialize it.
		{
			goto __TERMINAL;
		}
		lpMgr->ReadyQueue[i] = lpReadyQueue;
	}

	lpMgr->lpCurrentKernelThread = NULL;

	bResult = TRUE;

__TERMINAL:
	if(!bResult)  //If failed to initialize the Kernel Thread Manager.
	{
		if(NULL != lpRunningQueue)  //Destroy the objects created just now.
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpRunningQueue);
		if(NULL != lpReadyQueue)
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpReadyQueue);
		if(NULL != lpSuspendedQueue)
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpSuspendedQueue);
		if(NULL != lpSleepingQueue)
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpSleepingQueue);
		if(NULL != lpTerminalQueue)
			ObjectManager.DestroyObject(&ObjectManager,(__COMMON_OBJECT*)lpTerminalQueue);
	}

	return bResult;
}

//
//CreateKernelThread's implementation.
//This routine do the following:
// 1. Create a kernel thread object by calling CreateObject;
// 2. Initializes the kernel thread object;
// 3. Create the kernel thread's stack by calling KMemAlloc;
// 4. Insert the kernel thread object into proper queue.
//

static __KERNEL_THREAD_OBJECT* CreateKernelThread(__COMMON_OBJECT*             lpThis,
												  DWORD                        dwStackSize,
												  DWORD                        dwStatus,
												  DWORD                        dwPriority,
												  __KERNEL_THREAD_ROUTINE      lpStartRoutine,
												  LPVOID                       lpRoutineParam,
												  LPVOID                       lpReserved,
												  LPSTR                        lpszName)
{
	__KERNEL_THREAD_OBJECT*             lpKernelThread      = NULL;
	__KERNEL_THREAD_MANAGER*            lpMgr               = NULL;
	LPVOID                              lpStack             = NULL;
	BOOL                                bSuccess            = FALSE;
	DWORD*                              lpStackPtr          = NULL;
	DWORD                               i;

	if((NULL == lpThis) || (NULL == lpStartRoutine))    //Parameter check.
		goto __TERMINAL;

	if((KERNEL_THREAD_STATUS_READY != dwStatus) &&      //The initation status of a kernel
		                                                //thread should only be READY or
														//SUSPENDED.If the initation status
														//is READY,then the kernel thread maybe
														//scheduled to run in the NEXT schedule
														//circle(please note the kernel thread
														//does not be scheduled immediately),
														//else,the kernel thread will be susp-
														//ended,the kernel thread in this status
														//can be activated by ResumeKernelThread
														//calls.
	   (KERNEL_THREAD_STATUS_SUSPENDED != dwStatus))
	    goto __TERMINAL;

	lpMgr = (__KERNEL_THREAD_MANAGER*)lpThis;

	lpKernelThread = (__KERNEL_THREAD_OBJECT*)ObjectManager.CreateObject(&ObjectManager,
		NULL,
		OBJECT_TYPE_KERNEL_THREAD);

	if(NULL == lpKernelThread)    //If failed to create the kernel thread object.
		goto __TERMINAL;

	if(!lpKernelThread->Initialize((__COMMON_OBJECT*)lpKernelThread))    //Failed to initialize.
		goto __TERMINAL;

	if(0 == dwStackSize)          //If the dwStackSize is zero,then allocate the default size's
		                          //stack.
	{
		dwStackSize = DEFAULT_STACK_SIZE;
	}
	else
	{
		if(dwStackSize < MIN_STACK_SIZE)    //If dwStackSize is too small.
		{
			dwStackSize = MIN_STACK_SIZE;
		}
	}

	lpStack = KMemAlloc(dwStackSize,KMEM_SIZE_TYPE_ANY);
	if(NULL == lpStack)    //Failed to create kernel thread stack.
	{
		goto __TERMINAL;
	}

	//The following code initializes the kernel thread object created just now.
	lpKernelThread->dwThreadID            = lpKernelThread->dwObjectID;
	lpKernelThread->dwThreadStatus        = dwStatus;
	lpKernelThread->dwThreadPriority      = dwPriority;
	lpKernelThread->dwScheduleCounter     = dwPriority;  //***** CAUTION!!! *****
	lpKernelThread->dwReturnValue         = 0L;
	lpKernelThread->dwTotalRunTime        = 0L;
	lpKernelThread->dwTotalMemSize        = 0L;

	lpKernelThread->bUsedMath             = FALSE;      //May be updated in the future.
	lpKernelThread->dwStackSize           = dwStackSize ? dwStackSize : DEFAULT_STACK_SIZE;
	lpKernelThread->lpInitStackPointer    = (LPVOID)((DWORD)lpStack + dwStackSize);
	lpKernelThread->KernelThreadRoutine   = lpStartRoutine;       //Will be updated.
	lpKernelThread->lpRoutineParam        = lpRoutineParam;

	lpKernelThread->ucMsgQueueHeader      = 0;
	lpKernelThread->ucMsgQueueTrial       = 0;
	lpKernelThread->ucCurrentMsgNum       = 0;

	lpKernelThread->dwLastError           = 0L;
	lpKernelThread->dwWaitingStatus       = OBJECT_WAIT_WAITING;

	//Copy kernel thread name.
	if(lpszName)
	{
		for(i = 0;i < MAX_THREAD_NAME - 1;i ++)
		{
			if(lpszName[i] == 0)  //End.
			{
				break;
			}
		lpKernelThread->KernelThreadName[i] = lpszName[i];
		}
	}
	lpKernelThread->KernelThreadName[i] = 0;  //Set string's terminator.

	//
	//The following routine initializes the hardware context
	//of the kernel thread.
	//It's implementation depends on the hardware platform,so
	//this routine is implemented in ARCH directory.
	//
	InitKernelThreadContext(lpKernelThread,KernelThreadWrapper);

	if(KERNEL_THREAD_STATUS_READY == dwStatus)         //Add into Ready Queue.
	{
		lpMgr->AddReadyKernelThread((__COMMON_OBJECT*)lpMgr,