MFC(4) MFC中使用事件(event)来线程同步

MFC中的Event以类比linux中的cond，条件变量——wait and signal

OpenDevice.h

#pragma once
class OpenDevice
{
public:
	OpenDevice(void);
	~OpenDevice(void);

public:
	CWinThread *m_pThread;

	HANDLE	m_hCom;
	HANDLE m_hWakeupEvent;

	BOOL Init(void);
	BOOL OpenSerial(void);
	static UINT work_thread(void *args);

	BOOL m_SetEvent(void);
};

OpenDevice.c

#include "stdafx.h"
#include "OpenDevice.h"


OpenDevice::OpenDevice(void)
{
	m_hCom = NULL;
	m_hWakeupEvent = NULL;
	m_pThread = NULL;
}


OpenDevice::~OpenDevice(void)
{
	if(NULL != m_hCom)
	{
		CloseHandle(m_hCom);
		m_hCom = NULL;
	}

	if(NULL != m_hWakeupEvent)
	{
		CloseHandle(m_hWakeupEvent);
		m_hWakeupEvent = NULL;
	}
}

//初始化事件，创建子线程
BOOL OpenDevice::Init(void)
{
	//创建并初始化事件
	m_hWakeupEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
	if(NULL == m_hWakeupEvent)
	{
		TRACE(strerror(GetLastError()));
		return FALSE;
	}

	//创建子线程（创建的时候立即运行）
	m_pThread = AfxBeginThread(work_thread, this);
	if(NULL == m_pThread)
	{
		TRACE(strerror(GetLastError()));
		return FALSE;
	}

	return TRUE;
}

BOOL OpenDevice::OpenSerial(void)
{
	if(NULL == m_hWakeupEvent)
	{
		return FALSE;
	}
	else
	{
		ResetEvent(m_hWakeupEvent);
	}

	//等待串口设备插入：当用户点击打开按钮时，发送事件，则WaitForSingleObject返回
	
	while(1)
	{
		TRACE("wait for event...\n");

#if 1
		//手动重置事件
		ResetEvent(m_hWakeupEvent);						

		DWORD res = WaitForSingleObject(m_hWakeupEvent, INFINITE);				//
		if(WAIT_OBJECT_0 != res)
		{
			TRACE(strerror(GetLastError()));
			
			continue;
		}
#endif
		TRACE("start CreateFile...\n");
		//打开串口文件
		m_hCom = CreateFile(	"COM3",
								GENERIC_WRITE | GENERIC_READ,
								0,
								NULL,
								OPEN_EXISTING,
								FILE_FLAG_OVERLAPPED,
								0);
		if(INVALID_HANDLE_VALUE == m_hCom)
		{
			TRACE(strerror(GetLastError()));
			AfxMessageBox("串口打开失败!");		
		}
		else
		{
			TRACE("open successful\n");
			return TRUE;
		}								
	}
}

UINT OpenDevice::work_thread(void *args)
{
	OpenDevice *pOpenDevice = (OpenDevice *)args;
	BOOL res = pOpenDevice->OpenSerial();
	if(TRUE == res)
	{
		while(1)
		{
			TRACE("read and write serial!\n");
			Sleep(5000);
		}
	}

	return 0;
}


BOOL OpenDevice::m_SetEvent(void)
{
	SetEvent(m_hWakeupEvent);

	return TRUE;
}

按钮响应函数：

void CEventDlg::OnBnClickedOpen()
{
	// TODO: 在此添加控件通知处理程序代码
	m_openDevice.m_SetEvent();
}