BOOL EnumProcesses(DWORD * lpidProcess, DWORD cb, DWORD*cbNeeded); |
DWORD GetModuleFileNameExA(HANDLE hProcess, HMODULE hModule,LPTSTR lpstrFileName, DWORD nsize); |
//获取当前进程总数 EnumProcesses(process_ids, sizeof(process_ids), &num_processes); //遍历进程 for (int i = 0; i < num_processes; i++) { //根据进程ID获取句柄 process[i] = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, 0, process_ids[i]); //通过句柄获取进程文件名 if (GetModuleFileNameExA(process[i], NULL, File_name, sizeof(fileName))) cout << fileName << endl; } |
DWORD WaitForSingleObject( HANDLE hHandle, // 等待对象的句柄 DWORD dwMilliseconds // 等待毫秒数,INFINITE表示无限等待 ); |
DWORD WaitForMultipleObjects(DWORD nCount,const HANDLE* pHandles,BOOL bWaitAll,DWORD dwMilliseconds); |
BOOL CloseHandle(HANDLE hObject); |
C运行时库 | 库文件 |
Single thread(static link) | libc.lib |
Debug single thread(static link) | Libcd.lib |
MultiThread(static link) | libcmt.lib |
Debug multiThread(static link) | libcmtd.lib |
MultiThread(dynamic link) | msvert.lib |
Debug multiThread(dynamic link) | msvertd.lib |
error LNK2001: unresolved external symbol __endthreadex error LNK2001: unresolved external symbol __beginthreadex |
UINT ThreadFunction(LPVOID pParam) { //线程处理代码 return0; } |
while(1) { WaitForSingleObject(…,…);//或WaitForMultipleObjects(…) //Do something } |
#include "windows.h" #include <process.h> class ExampleTask { public: void taskmain(LPVOID param); void StartTask(); }; void ExampleTask::taskmain(LPVOID param) {} void ExampleTask::StartTask() { _beginthread(taskmain,0,NULL); } int main(int argc, char* argv[]) { ExampleTask realTimeTask; realTimeTask.StartTask(); return 0; } |
error C2664: '_beginthread' : cannot convert parameter 1 from 'void (void *)' to 'void (__cdecl *)(void *)' None of the functions with this name in scope match the target type |
#include "windows.h" #include <process.h> class ExampleTask { public: void taskmain(LPVOID param); }; void ExampleTask::taskmain(LPVOID param) {} int main(int argc, char* argv[]) { ExampleTask realTimeTask; _beginthread(ExampleTask::taskmain,0,NULL); return 0; } |
error C2664: '_beginthread' : cannot convert parameter 1 from 'void (void *)' to 'void (__cdecl *)(void *)' None of the functions with this name in scope match the target type |
#include "windows.h" #include <process.h> class ExampleTask { public: void static taskmain(LPVOID param); void StartTask(); }; void ExampleTask::taskmain(LPVOID param) {} void ExampleTask::StartTask() { _beginthread(taskmain,0,NULL); } int main(int argc, char* argv[]) { ExampleTask realTimeTask; realTimeTask.StartTask(); return 0; } 和 #include "windows.h" #include <process.h> class ExampleTask { public: void static taskmain(LPVOID param); }; void ExampleTask::taskmain(LPVOID param) {} int main(int argc, char* argv[]) { _beginthread(ExampleTask::taskmain,0,NULL); return 0; } |
#include "windows.h" #include <process.h> class ExampleTask { public: friend void taskmain(LPVOID param); void StartTask(); }; void taskmain(LPVOID param) { ExampleTask * pTaskMain = (ExampleTask *) param; //通过pTaskMain指针引用 } void ExampleTask::StartTask() { _beginthread(taskmain,0,this); } int main(int argc, char* argv[]) { ExampleTask realTimeTask; realTimeTask.StartTask(); return 0; } |
HANDLE CreateThread( LPSECURITY_ATTRIBUTES lpThreadAttributes,//Pointer to a SECURITY_ATTRIBUTES structure SIZE_T dwStackSize, //Initial size of the stack, in bytes. LPTHREAD_START_ROUTINE lpStartAddress, LPVOID lpParameter, //Pointer to a variable to be passed to the thread DWORD dwCreationFlags, //Flags that control the creation of the thread LPDWORD lpThreadId //Pointer to a variable that receives the thread identifier ); |
uintptr_t _beginthread( void( __cdecl *start_address )( void * ), //Start address of routine that begins execution of new thread unsigned stack_size, //Stack size for new thread or 0. void *arglist //Argument list to be passed to new thread or NULL ); uintptr_t _beginthreadex( void *security,//Pointer to a SECURITY_ATTRIBUTES structure unsigned stack_size, unsigned ( __stdcall *start_address )( void * ), void *arglist, unsigned initflag,//Initial state of new thread (0 for running or CREATE_SUSPENDED for suspended); unsigned *thrdaddr ); |
VOID ExitThread(UINT fuExitCode ); |
BOOL TerminateThread(HANDLE hThread,DWORD dwExitCode); |
DWORD ResumeThread(HANDLE hThread); |
DWORD SuspendThread(HANDLE hThread); |
BOOL SetThreadPriority(HANDLE hThread, int nPriority); |
HANDLE hCurrentThread = GetCurrentThread(); //获得该线程句柄 SetThreadPriority(hCurrentThread, THREAD_PRIORITY_LOWEST); |
VOID Sleep(DWORD dwMilliseconds); |
Int GetThreadPriority (HANDLE hThread); |
BOOL WINAPI GetExitCodeThread( HANDLE hThread, LPDWORD lpExitCode ); |
获得/设置线程上下文 BOOL WINAPI GetThreadContext( HANDLE hThread, LPCONTEXT lpContext ); BOOL WINAPI SetThreadContext( HANDLE hThread, CONST CONTEXT *lpContext ); |
#define WIN32_LEAN_AND_MEAN #include <stdio.h> #include <stdlib.h> #include <windows.h> #include <conio.h> DWORD WINAPI ThreadFunc(LPVOID); int main() { HANDLE hThrd1; HANDLE hThrd2; DWORD exitCode1 = 0; DWORD exitCode2 = 0; DWORD threadId; hThrd1 = CreateThread(NULL, 0, ThreadFunc, (LPVOID)1, 0, &threadId ); if (hThrd1) printf("Thread 1 launched\n"); hThrd2 = CreateThread(NULL, 0, ThreadFunc, (LPVOID)2, 0, &threadId ); if (hThrd2) printf("Thread 2 launched\n"); // Keep waiting until both calls to GetExitCodeThread succeed AND // neither of them returns STILL_ACTIVE. for (;;) { printf("Press any key to exit..\n"); getch(); GetExitCodeThread(hThrd1, &exitCode1); GetExitCodeThread(hThrd2, &exitCode2); if ( exitCode1 == STILL_ACTIVE ) puts("Thread 1 is still running!"); if ( exitCode2 == STILL_ACTIVE ) puts("Thread 2 is still running!"); if ( exitCode1 != STILL_ACTIVE && exitCode2 != STILL_ACTIVE ) break; } CloseHandle(hThrd1); CloseHandle(hThrd2); printf("Thread 1 returned %d\n", exitCode1); printf("Thread 2 returned %d\n", exitCode2); return EXIT_SUCCESS; } /* * Take the startup value, do some simple math on it, * and return the calculated value. */ DWORD WINAPI ThreadFunc(LPVOID n) { Sleep((DWORD)n*1000*2); return (DWORD)n * 10; } |
#define WIN32_LEAN_AND_MEAN #include <stdio.h> #include <stdlib.h> #include <windows.h> DWORD WINAPI ThreadFunc(LPVOID); int main() { HANDLE hThrd; DWORD threadId; int i; for (i = 0; i < 5; i++) { hThrd = CreateThread(NULL, 0, ThreadFunc, (LPVOID)i, 0, &threadId); if (hThrd) { printf("Thread launched %d\n", i); CloseHandle(hThrd); } } // Wait for the threads to complete. Sleep(2000); return EXIT_SUCCESS; } DWORD WINAPI ThreadFunc(LPVOID n) { int i; for (i = 0; i < 10; i++) printf("%d%d%d%d%d%d%d%d\n", n, n, n, n, n, n, n, n); return 0; } |
#include <Win32.h> #include <stdio.h> #include <process.h> unsigned Counter; unsigned __stdcall SecondThreadFunc(void *pArguments) { printf("In second thread...\n"); while (Counter < 1000000) Counter++; _endthreadex(0); return 0; } int main() { HANDLE hThread; unsigned threadID; printf("Creating second thread...\n"); // Create the second thread. hThread = (HANDLE)_beginthreadex(NULL, 0, &SecondThreadFunc, NULL, 0, &threadID); // Wait until second thread terminates WaitForSingleObject(hThread, INFINITE); printf("Counter should be 1000000; it is-> %d\n", Counter); // Destroy the thread object. CloseHandle(hThread); } |
int var; //全局变量 UINT ThreadFunction(LPVOIDpParam) { var = 0; while (var < MaxValue) { //线程处理 ::InterlockedIncrement(long*) &var); } return 0; } 请看下列程序: int globalFlag = false; DWORD WINAPI ThreadFunc(LPVOID n) { Sleep(2000); globalFlag = true; return 0; } int main() { HANDLE hThrd; DWORD threadId; hThrd = CreateThread(NULL, 0, ThreadFunc, NULL, 0, &threadId); if (hThrd) { printf("Thread launched\n"); CloseHandle(hThrd); } while (!globalFlag) ; printf("exit\n"); } |
HANDLE CreateEvent( LPSECURITY_ATTRIBUTES lpEventAttributes, // SECURITY_ATTRIBUTES结构指针,可为NULL BOOL bManualReset, // 手动/自动 // TRUE:在WaitForSingleObject后必须手动调用ResetEvent清除信号 // FALSE:在WaitForSingleObject后,系统自动清除事件信号 BOOL bInitialState, //初始状态 LPCTSTR lpName //事件的名称 ); |
HANDLE hEvent=OpenEvent(EVENT_ALL_ACCESS,true,"MyEvent"); ResetEvent(hEvent); |
CRITICAL_SECTION gCriticalSection; |
VOID WINAPI InitializeCriticalSection( LPCRITICAL_SECTION lpCriticalSection //指向程序员定义的CRITICAL_SECTION变量 ); |
VOID WINAPI DeleteCriticalSection( LPCRITICAL_SECTION lpCriticalSection //指向一个不再需要的CRITICAL_SECTION变量 ); |
VOID WINAPI EnterCriticalSection( LPCRITICAL_SECTION lpCriticalSection //指向一个你即将锁定的CRITICAL_SECTION变量 ); |
VOID WINAPI LeaveCriticalSection( LPCRITICAL_SECTION lpCriticalSection //指向一个你即将离开的CRITICAL_SECTION变量 ); |
void UpdateData() { EnterCriticalSection(&gCriticalSection); ...//do something LeaveCriticalSection(&gCriticalSection); } |
HANDLE CreateMutex( LPSECURITY_ATTRIBUTES lpMutexAttributes, // 安全属性结构指针,可为NULL BOOL bInitialOwner, //是否占有该互斥量,TRUE:占有,FALSE:不占有 LPCTSTR lpName //信号量的名称 ); |
HANDLE hMutex; hMutex = OpenMutex(MUTEX_ALL_ACCESS, FALSE, L"mutexName"); if (hMutex){ … } else{ … } |
BOOL WINAPI ReleaseMutex( HANDLE hMutex ); |
void UpdateResource() { WaitForSingleObject(hMutex,…); ...//do something ReleaseMutex(hMutex); } |
HANDLE CreateSemaphore ( PSECURITY_ATTRIBUTE psa, LONG lInitialCount, //开始时可供使用的资源数 LONG lMaximumCount, //最大资源数 PCTSTR pszName); |
BOOL WINAPI ReleaseSemaphore( HANDLE hSemaphore, LONG lReleaseCount, //信号量的当前资源数增加lReleaseCount LPLONG lpPreviousCount ); |
HANDLE OpenSemaphore ( DWORD fdwAccess, BOOL bInherithandle, PCTSTR pszName ); |
int globalVar = 0; DWORD WINAPI ThreadFunc1(LPVOID n) { globalVar++; return 0; } DWORD WINAPI ThreadFunc2(LPVOID n) { globalVar++; return 0; } |
00401038 mov eax,[globalVar (0042d3f0)] 0040103D add eax,1 00401040 mov [globalVar (0042d3f0)],eax |
int globalVar = 0; DWORD WINAPI ThreadFunc1(LPVOID n) { InterlockedExchangeAdd(&globalVar,1); return 0; } DWORD WINAPI ThreadFunc2(LPVOID n) { InterlockedExchangeAdd(&globalVar,1); return 0; } |
HANDLE CreateWaitableTimer( PSECURITY_ATTRISUTES psa, BOOL fManualReset,//人工重置或自动重置定时器 PCTSTR pszName); |
BOOL SetWaitableTimer( HANDLE hTimer, //要设置的定时器 const LARGE_INTEGER *pDueTime, //指明定时器第一次激活的时间 LONG lPeriod, //指明此后定时器应该间隔多长时间激活一次 PTIMERAPCROUTINE pfnCompletionRoutine, PVOID PvArgToCompletionRoutine, BOOL fResume); |
BOOl Cancel WaitableTimer( HANDLE hTimer //要取消的定时器 ); |
HANDLE OpenWaitableTimer ( DWORD fdwAccess, BOOL bInherithandle, PCTSTR pszName ); |
#include <windows.h> #include <stdio.h> CRITICAL_SECTION cs1, cs2; long WINAPI ThreadFn(long); main() { long iThreadID; InitializeCriticalSection(&cs1); InitializeCriticalSection(&cs2); CloseHandle(CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)ThreadFn, NULL, 0,&iThreadID)); while (TRUE) { EnterCriticalSection(&cs1); printf("\n线程1占用临界区1"); EnterCriticalSection(&cs2); printf("\n线程1占用临界区2"); printf("\n线程1占用两个临界区"); LeaveCriticalSection(&cs2); LeaveCriticalSection(&cs1); printf("\n线程1释放两个临界区"); Sleep(20); }; return (0); } long WINAPI ThreadFn(long lParam) { while (TRUE) { EnterCriticalSection(&cs2); printf("\n线程2占用临界区2"); EnterCriticalSection(&cs1); printf("\n线程2占用临界区1"); printf("\n线程2占用两个临界区"); LeaveCriticalSection(&cs1); LeaveCriticalSection(&cs2); printf("\n线程2释放两个临界区"); Sleep(20); }; } |
long WINAPI ThreadFn(long lParam) { while (TRUE) { EnterCriticalSection(&cs1); printf("\n线程2占用临界区1"); EnterCriticalSection(&cs2); printf("\n线程2占用临界区2"); printf("\n线程2占用两个临界区"); LeaveCriticalSection(&cs1); LeaveCriticalSection(&cs2); printf("\n线程2释放两个临界区"); Sleep(20); }; } |
HADLE CreateFile(PCTSTR lpFileName, //通信端口名,如"COM1" WORD dwDesiredAccess, //对资源的访问类型 WORD dwShareMode, //指定共享模式,COM不能共享,该参数为0 PSECURITY_ATTRIBUTES lpSecurityAttributes, //安全描述符指针,可为NULL WORD dwCreationDisposition, //创建方式 WORD dwFlagsAndAttributes, //文件属性,可为NULL HANDLE hTemplateFile //模板文件句柄,置为NULL ); |
BOOL WINAPI GetCommState( HANDLE hFile, //标识通信端口的句柄 LPDCB lpDCB //指向一个设备控制块(DCB结构)的指针 ); |
BOOL SetCommState( HANDLE hFile, //标识通信端口的句柄 LPDCB lpDCB //指向一个设备控制块(DCB结构)的指针 ); |
typedef struct _DCB { // dcb DWORD DCBlength; // sizeof(DCB) DWORD BaudRate; // current baud rate DWORD fBinary: 1; // binary mode, no EOF check DWORD fParity: 1; // enable parity checking DWORD fOutxCtsFlow: 1; // CTS output flow control DWORD fOutxDsrFlow: 1; // DSR output flow control DWORD fDtrControl: 2; // DTR flow control type DWORD fDsrSensitivity: 1; // DSR sensitivity DWORD fTXContinueOnXoff: 1; // XOFF continues Tx DWORD fOutX: 1; // XON/XOFF out flow control DWORD fInX: 1; // XON/XOFF in flow control DWORD fErrorChar: 1; // enable error replacement DWORD fNull: 1; // enable null stripping DWORD fRtsControl: 2; // RTS flow control DWORD fAbortOnError: 1; // abort reads/writes on error DWORD fDummy2: 17; // reserved WORD wReserved; // not currently used WORD XonLim; // transmit XON threshold WORD XoffLim; // transmit XOFF threshold BYTE ByteSize; // number of bits/byte, 4-8 BYTE Parity; // 0-4=no,odd,even,mark,space BYTE StopBits; // 0,1,2 = 1, 1.5, 2 char XonChar; // Tx and Rx XON character char XoffChar; // Tx and Rx XOFF character char ErrorChar; // error replacement character char EofChar; // end of input character char EvtChar; // received event character WORD wReserved1; // reserved; do not use } DCB; |
BOOL SetCommMask( HANDLE hFile, //标识通信端口的句柄 DWORD dwEvtMask //能够使能的通信事件 ); |
值 | 事件描述 |
EV_BREAK | A break was detected on input. |
EV_CTS | The CTS (clear-to-send) signal changed state. |
EV_DSR | The DSR(data-set-ready) signal changed state. |
EV_ERR | A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY. |
EV_RING | A ring indicator was detected. |
EV_RLSD | The RLSD (receive-line-signal-detect) signal changed state. |
EV_RXCHAR | A character was received and placed in the input buffer. |
EV_RXFLAG | The event character was received and placed in the input buffer. The event character is specified in the device's DCB structure, which is applied to a serial port by using the SetCommState function. |
EV_TXEMPTY | The last character in the output buffer was sent. |
BOOL WaitCommEvent( HANDLE hFile, //标识通信端口的句柄 LPDWORD lpEvtMask, //指向存放事件标识变量的指针 LPOVERLAPPED lpOverlapped, // 指向overlapped结构 ); |
BOOL ReadFile(HANDLE hFile, //标识通信端口的句柄 LPVOID lpBuffer, //输入数据Buffer指针 DWORD nNumberOfBytesToRead, // 需要读取的字节数 LPDWORD lpNumberOfBytesRead, //实际读取的字节数指针 LPOVERLAPPED lpOverlapped //指向overlapped结构 ); BOOL WriteFile(HANDLE hFile, //标识通信端口的句柄 LPCVOID lpBuffer, //输出数据Buffer指针 DWORD nNumberOfBytesToWrite, //需要写的字节数 LPDWORD lpNumberOfBytesWritten, //实际写入的字节数指针 LPOVERLAPPED lpOverlapped //指向overlapped结构 ); |
BOOL CMultiThreadComApp::InitInstance() { AfxEnableControlContainer(); //打开并设置COM1 hComm1=CreateFile("COM1", GENERIC_READ|GENERIC_WRITE, 0, NULL ,OPEN_EXISTING, 0,NULL); if (hComm1==(HANDLE)-1) { AfxMessageBox("打开COM1失败"); return false; } else { DCB wdcb; GetCommState (hComm1,&wdcb); wdcb.BaudRate=9600; SetCommState (hComm1,&wdcb); PurgeComm(hComm1,PURGE_TXCLEAR); } //打开并设置COM2 hComm2=CreateFile("COM2", GENERIC_READ|GENERIC_WRITE, 0, NULL ,OPEN_EXISTING, 0,NULL); if (hComm2==(HANDLE)-1) { AfxMessageBox("打开COM2失败"); return false; } else { DCB wdcb; GetCommState (hComm2,&wdcb); wdcb.BaudRate=9600; SetCommState (hComm2,&wdcb); PurgeComm(hComm2,PURGE_TXCLEAR); } CMultiThreadComDlg dlg; m_pMainWnd = &dlg; int nResponse = dlg.DoModal(); if (nResponse == IDOK) { // TODO: Place code here to handle when the dialog is // dismissed with OK } else if (nResponse == IDCANCEL) { // TODO: Place code here to handle when the dialog is // dismissed with Cancel } return FALSE; } |
BOOL CMultiThreadComDlg::OnInitDialog() { CDialog::OnInitDialog(); // Add "About..." menu item to system menu. // IDM_ABOUTBOX must be in the system command range. ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX); ASSERT(IDM_ABOUTBOX < 0xF000); CMenu* pSysMenu = GetSystemMenu(FALSE); if (pSysMenu != NULL) { CString strAboutMenu; strAboutMenu.LoadString(IDS_ABOUTBOX); if (!strAboutMenu.IsEmpty()) { pSysMenu->AppendMenu(MF_SEPARATOR); pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu); } } // Set the icon for this dialog. The framework does this automatically // when the application's main window is not a dialog SetIcon(m_hIcon, TRUE); // Set big icon SetIcon(m_hIcon, FALSE); // Set small icon // TODO: Add extra initialization here //启动串口1处理线程 DWORD nThreadId1; hCommThread1 = ::CreateThread((LPSECURITY_ATTRIBUTES)NULL, 0, (LPTHREAD_START_ROUTINE)Com1ThreadProcess, AfxGetMainWnd()->m_hWnd, 0, &nThreadId1); if (hCommThread1 == NULL) { AfxMessageBox("创建串口1处理线程失败"); return false; } //启动串口2处理线程 DWORD nThreadId2; hCommThread2 = ::CreateThread((LPSECURITY_ATTRIBUTES)NULL, 0, (LPTHREAD_START_ROUTINE)Com2ThreadProcess, AfxGetMainWnd()->m_hWnd, 0, &nThreadId2); if (hCommThread2 == NULL) { AfxMessageBox("创建串口2处理线程失败"); return false; } return TRUE; // return TRUE unless you set the focus to a control } |
DWORD WINAPI Com1ThreadProcess(HWND hWnd//主窗口句柄) { DWORD wEven; char str[10]; //读入数据 SetCommMask(hComm1, EV_RXCHAR | EV_TXEMPTY); while (TRUE) { WaitCommEvent(hComm1, &wEven, NULL); if(wEven = 0) { CloseHandle(hCommThread1); hCommThread1 = NULL; ExitThread(0); } else { switch (wEven) { case EV_TXEMPTY: if (wTxPos < wTxLen) { //在串口1写入数据 DWORD wCount; //写入的字节数 WriteFile(hComm1, com1Data.TxBuf[wTxPos], 1, &wCount, NULL); com1Data.wTxPos++; } break; case EV_RXCHAR: if (com1Data.wRxPos < com1Data.wRxLen) { //读取串口数据, 处理收到的数据 DWORD wCount; //读取的字节数 ReadFile(hComm1, com1Data.RxBuf[wRxPos], 1, &wCount, NULL); com1Data.wRxPos++; if(com1Data.wRxPos== com1Data.wRxLen); ::PostMessage(hWnd, COM_SENDCHAR, 0, 1); } break; } } } } return TRUE; } DWORD WINAPI Com2ThreadProcess(HWND hWnd //主窗口句柄) { DWORD wEven; char str[10]; //读入数据 SetCommMask(hComm2, EV_RXCHAR | EV_TXEMPTY); while (TRUE) { WaitCommEvent(hComm2, &wEven, NULL); if (wEven = 0) { CloseHandle(hCommThread2); hCommThread2 = NULL; ExitThread(0); } else { switch (wEven) { case EV_TXEMPTY: if (wTxPos < wTxLen) { //在串口2写入数据 DWORD wCount; //写入的字节数 WriteFile(hComm2, com2Data.TxBuf[wTxPos], 1, &wCount, NULL); com2Data.wTxPos++; } break; case EV_RXCHAR: if (com2Data.wRxPos < com2Data.wRxLen) { //读取串口数据, 处理收到的数据 DWORD wCount; //读取的字节数 ReadFile(hComm2, com2Data.RxBuf[wRxPos], 1, &wCount, NULL); com2Data.wRxPos++; if(com2Data.wRxPos== com2Data.wRxLen); ::PostMessage(hWnd, COM_SENDCHAR, 0, 1); } break; } } } return TRUE; } |
typedef struct tagSerialPort { BYTE RxBuf[SPRX_BUFLEN];//接收Buffer WORD wRxPos; //当前接收字节位置 WORD wRxLen; //要接收的字节数 BYTE TxBuf[SPTX_BUFLEN];//发送Buffer WORD wTxPos; //当前发送字节位置 WORD wTxLen; //要发送的字节数 }SerialPort, * LPSerialPort; |
#ifndef __SERIALPORT_H__ #define __SERIALPORT_H__ #define WM_COMM_BREAK_DETECTED WM_USER+1 // A break was detected on input. #define WM_COMM_CTS_DETECTED WM_USER+2 // The CTS (clear-to-send) signal changed state. #define WM_COMM_DSR_DETECTED WM_USER+3 // The DSR (data-set-ready) signal changed state. #define WM_COMM_ERR_DETECTED WM_USER+4 // A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY. #define WM_COMM_RING_DETECTED WM_USER+5 // A ring indicator was detected. #define WM_COMM_RLSD_DETECTED WM_USER+6 // The RLSD (receive-line-signal-detect) signal changed state. #define WM_COMM_RXCHAR WM_USER+7 // A character was received and placed in the input buffer. #define WM_COMM_RXFLAG_DETECTED WM_USER+8 // The event character was received and placed in the input buffer. #define WM_COMM_TXEMPTY_DETECTED WM_USER+9 // The last character in the output buffer was sent. class CSerialPort { public: // contruction and destruction CSerialPort(); virtual ~CSerialPort(); // port initialisation BOOL InitPort(CWnd* pPortOwner, UINT portnr = 1, UINT baud = 19200, char parity = 'N', UINT databits = 8, UINT stopsbits = 1, DWORD dwCommEvents = EV_RXCHAR | EV_CTS, UINT nBufferSize = 512); // start/stop comm watching BOOL StartMonitoring(); BOOL RestartMonitoring(); BOOL StopMonitoring(); DWORD GetWriteBufferSize(); DWORD GetCommEvents(); DCB GetDCB(); void WriteToPort(char* string); protected: // protected memberfunctions void ProcessErrorMessage(char* ErrorText); static UINT CommThread(LPVOID pParam); static void ReceiveChar(CSerialPort* port, COMSTAT comstat); static void WriteChar(CSerialPort* port); // thread CWinThread* m_Thread; // synchronisation objects CRITICAL_SECTION m_csCommunicationSync; BOOL m_bThreadAlive; // handles HANDLE m_hShutdownEvent; HANDLE m_hComm; HANDLE m_hWriteEvent; // Event array. // One element is used for each event. There are two event handles for each port. // A Write event and a receive character event which is located in the overlapped structure (m_ov.hEvent). // There is a general shutdown when the port is closed. HANDLE m_hEventArray[3]; // structures OVERLAPPED m_ov; COMMTIMEOUTS m_CommTimeouts; DCB m_dcb; // owner window CWnd* m_pOwner; // misc UINT m_nPortNr; char* m_szWriteBuffer; DWORD m_dwCommEvents; DWORD m_nWriteBufferSize; }; #endif __SERIALPORT_H__ |
CSerialPort::CSerialPort() { m_hComm = NULL; // initialize overlapped structure members to zero m_ov.Offset = 0; m_ov.OffsetHigh = 0; // create events m_ov.hEvent = NULL; m_hWriteEvent = NULL; m_hShutdownEvent = NULL; m_szWriteBuffer = NULL; m_bThreadAlive = FALSE; } // // Delete dynamic memory // CSerialPort::~CSerialPort() { do { SetEvent(m_hShutdownEvent); } while (m_bThreadAlive); TRACE("Thread ended\n"); delete []m_szWriteBuffer; } |
BOOL CSerialPort::InitPort(CWnd *pPortOwner, // the owner (CWnd) of the port (receives message) UINT portnr, // portnumber (1..4) UINT baud, // baudrate char parity, // parity UINT databits, // databits UINT stopbits, // stopbits DWORD dwCommEvents, // EV_RXCHAR, EV_CTS etc UINT writebuffersize) // size to the writebuffer { assert(portnr > 0 && portnr < 5); assert(pPortOwner != NULL); // if the thread is alive: Kill if (m_bThreadAlive) { do { SetEvent(m_hShutdownEvent); } while (m_bThreadAlive); TRACE("Thread ended\n"); } // create events if (m_ov.hEvent != NULL) ResetEvent(m_ov.hEvent); m_ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); if (m_hWriteEvent != NULL) ResetEvent(m_hWriteEvent); m_hWriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL); if (m_hShutdownEvent != NULL) ResetEvent(m_hShutdownEvent); m_hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL); // initialize the event objects m_hEventArray[0] = m_hShutdownEvent; // highest priority m_hEventArray[1] = m_ov.hEvent; m_hEventArray[2] = m_hWriteEvent; // initialize critical section InitializeCriticalSection(&m_csCommunicationSync); // set buffersize for writing and save the owner m_pOwner = pPortOwner; if (m_szWriteBuffer != NULL) delete []m_szWriteBuffer; m_szWriteBuffer = new char[writebuffersize]; m_nPortNr = portnr; m_nWriteBufferSize = writebuffersize; m_dwCommEvents = dwCommEvents; BOOL bResult = FALSE; char *szPort = new char[50]; char *szBaud = new char[50]; // now it critical! EnterCriticalSection(&m_csCommunicationSync); // if the port is already opened: close it if (m_hComm != NULL) { CloseHandle(m_hComm); m_hComm = NULL; } // prepare port strings sprintf(szPort, "COM%d", portnr); sprintf(szBaud, "baud=%d parity=%c data=%d stop=%d", baud, parity, databits,stopbits); // get a handle to the port m_hComm = CreateFile(szPort, // communication port string (COMX) GENERIC_READ | GENERIC_WRITE, // read/write types 0, // comm devices must be opened with exclusive access NULL, // no security attributes OPEN_EXISTING, // comm devices must use OPEN_EXISTING FILE_FLAG_OVERLAPPED, // Async I/O 0); // template must be 0 for comm devices if (m_hComm == INVALID_HANDLE_VALUE) { // port not found delete []szPort; delete []szBaud; return FALSE; } // set the timeout values m_CommTimeouts.ReadIntervalTimeout = 1000; m_CommTimeouts.ReadTotalTimeoutMultiplier = 1000; m_CommTimeouts.ReadTotalTimeoutConstant = 1000; m_CommTimeouts.WriteTotalTimeoutMultiplier = 1000; m_CommTimeouts.WriteTotalTimeoutConstant = 1000; // configure if (SetCommTimeouts(m_hComm, &m_CommTimeouts)) { if (SetCommMask(m_hComm, dwCommEvents)) { if (GetCommState(m_hComm, &m_dcb)) { m_dcb.fRtsControl = RTS_CONTROL_ENABLE; // set RTS bit high! if (BuildCommDCB(szBaud, &m_dcb)) { if (SetCommState(m_hComm, &m_dcb)) ; // normal operation... continue else ProcessErrorMessage("SetCommState()"); } else ProcessErrorMessage("BuildCommDCB()"); } else ProcessErrorMessage("GetCommState()"); } else ProcessErrorMessage("SetCommMask()"); } else ProcessErrorMessage("SetCommTimeouts()"); delete []szPort; delete []szBaud; // flush the port PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT); // release critical section LeaveCriticalSection(&m_csCommunicationSync); TRACE("Initialisation for communicationport %d completed.\nUse Startmonitor to communicate.\n", portnr); return TRUE; } |
UINT CSerialPort::CommThread(LPVOID pParam) { // Cast the void pointer passed to the thread back to // a pointer of CSerialPort class CSerialPort *port = (CSerialPort*)pParam; // Set the status variable in the dialog class to // TRUE to indicate the thread is running. port->m_bThreadAlive = TRUE; // Misc. variables DWORD BytesTransfered = 0; DWORD Event = 0; DWORD CommEvent = 0; DWORD dwError = 0; COMSTAT comstat; BOOL bResult = TRUE; // Clear comm buffers at startup if (port->m_hComm) // check if the port is opened PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT); // begin forever loop. This loop will run as long as the thread is alive. for (;;) { // Make a call to WaitCommEvent(). This call will return immediatly // because our port was created as an async port (FILE_FLAG_OVERLAPPED // and an m_OverlappedStructerlapped structure specified). This call will cause the // m_OverlappedStructerlapped element m_OverlappedStruct.hEvent, which is part of the m_hEventArray to // be placed in a non-signeled state if there are no bytes available to be read, // or to a signeled state if there are bytes available. If this event handle // is set to the non-signeled state, it will be set to signeled when a // character arrives at the port. // we do this for each port! bResult = WaitCommEvent(port->m_hComm, &Event, &port->m_ov); if (!bResult) { // If WaitCommEvent() returns FALSE, process the last error to determin // the reason.. switch (dwError = GetLastError()) { case ERROR_IO_PENDING: { // This is a normal return value if there are no bytes // to read at the port. // Do nothing and continue break; } case 87: { // Under Windows NT, this value is returned for some reason. // I have not investigated why, but it is also a valid reply // Also do nothing and continue. break; } default: { // All other error codes indicate a serious error has // occured. Process this error. port->ProcessErrorMessage("WaitCommEvent()"); break; } } } else { // If WaitCommEvent() returns TRUE, check to be sure there are // actually bytes in the buffer to read. // // If you are reading more than one byte at a time from the buffer // (which this program does not do) you will have the situation occur // where the first byte to arrive will cause the WaitForMultipleObjects() // function to stop waiting. The WaitForMultipleObjects() function // resets the event handle in m_OverlappedStruct.hEvent to the non-signelead state // as it returns. // // If in the time between the reset of this event and the call to // ReadFile() more bytes arrive, the m_OverlappedStruct.hEvent handle will be set again // to the signeled state. When the call to ReadFile() occurs, it will // read all of the bytes from the buffer, and the program will // loop back around to WaitCommEvent(). // // At this point you will be in the situation where m_OverlappedStruct.hEvent is set, // but there are no bytes available to read. If you proceed and call // ReadFile(), it will return immediatly due to the async port setup, but // GetOverlappedResults() will not return until the next character arrives. // // It is not desirable for the GetOverlappedResults() function to be in // this state. The thread shutdown event (event 0) and the WriteFile() // event (Event2) will not work if the thread is blocked by GetOverlappedResults(). // // The solution to this is to check the buffer with a call to ClearCommError(). // This call will reset the event handle, and if there are no bytes to read // we can loop back through WaitCommEvent() again, then proceed. // If there are really bytes to read, do nothing and proceed. bResult = ClearCommError(port->m_hComm, &dwError, &comstat); if (comstat.cbInQue == 0) continue; } // end if bResult // Main wait function. This function will normally block the thread // until one of nine events occur that require action. Event = WaitForMultipleObjects(3, port->m_hEventArray, FALSE, INFINITE); switch (Event) { case 0: { // Shutdown event. This is event zero so it will be // the higest priority and be serviced first. port->m_bThreadAlive = FALSE; // Kill this thread. break is not needed, but makes me feel better. AfxEndThread(100); break; } case 1: // read event { GetCommMask(port->m_hComm, &CommEvent); if (CommEvent &EV_CTS) ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_CTS_DETECTED, (WPARAM)0, (LPARAM)port->m_nPortNr); if (CommEvent &EV_RXFLAG) ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RXFLAG_DETECTED,(WPARAM)0, (LPARAM)port->m_nPortNr); if (CommEvent &EV_BREAK) ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_BREAK_DETECTED,(WPARAM)0, (LPARAM)port->m_nPortNr); if (CommEvent &EV_ERR) ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_ERR_DETECTED, (WPARAM)0, (LPARAM)port->m_nPortNr); if (CommEvent &EV_RING) ::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RING_DETECTED,(WPARAM)0, (LPARAM)port->m_nPortNr); if (CommEvent &EV_RXCHAR) // Receive character event from port. ReceiveChar(port, comstat); break; } case 2: // write event { // Write character event from port WriteChar(port); break; } } // end switch } // close forever loop return 0; } |
// // start comm watching // BOOL CSerialPort::StartMonitoring() { if (!(m_Thread = AfxBeginThread(CommThread, this))) return FALSE; TRACE("Thread started\n"); return TRUE; } // // Restart the comm thread // BOOL CSerialPort::RestartMonitoring() { TRACE("Thread resumed\n"); m_Thread->ResumeThread(); return TRUE; } // // Suspend the comm thread // BOOL CSerialPort::StopMonitoring() { TRACE("Thread suspended\n"); m_Thread->SuspendThread(); return TRUE; } |
// // Write a character. // void CSerialPort::WriteChar(CSerialPort *port) { BOOL bWrite = TRUE; BOOL bResult = TRUE; DWORD BytesSent = 0; ResetEvent(port->m_hWriteEvent); // Gain ownership of the critical section EnterCriticalSection(&port->m_csCommunicationSync); if (bWrite) { // Initailize variables port->m_ov.Offset = 0; port->m_ov.OffsetHigh = 0; // Clear buffer PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT); bResult = WriteFile(port->m_hComm, // Handle to COMM Port port->m_szWriteBuffer, // Pointer to message buffer in calling finction strlen((char*)port->m_szWriteBuffer), // Length of message to send &BytesSent, // Where to store the number of bytes sent &port->m_ov); // Overlapped structure // deal with any error codes if (!bResult) { DWORD dwError = GetLastError(); switch (dwError) { case ERROR_IO_PENDING: { // continue to GetOverlappedResults() BytesSent = 0; bWrite = FALSE; break; } default: { // all other error codes port->ProcessErrorMessage("WriteFile()"); } } } else { LeaveCriticalSection(&port->m_csCommunicationSync); } } // end if(bWrite) if (!bWrite) { bWrite = TRUE; bResult = GetOverlappedResult(port->m_hComm, // Handle to COMM port &port->m_ov, // Overlapped structure &BytesSent, // Stores number of bytes sent TRUE); // Wait flag LeaveCriticalSection(&port->m_csCommunicationSync); // deal with the error code if (!bResult) { port->ProcessErrorMessage("GetOverlappedResults() in WriteFile()"); } } // end if (!bWrite) // Verify that the data size send equals what we tried to send if (BytesSent != strlen((char*)port->m_szWriteBuffer)) { TRACE("WARNING: WriteFile() error.. Bytes Sent: %d; Message Length: %d\n", BytesSent, strlen((char*)port->m_szWriteBuffer)); } } // // Character received. Inform the owner // void CSerialPort::ReceiveChar(CSerialPort *port, COMSTAT comstat) { BOOL bRead = TRUE; BOOL bResult = TRUE; DWORD dwError = 0; DWORD BytesRead = 0; unsigned char RXBuff; for (;;) { // Gain ownership of the comm port critical section. // This process guarantees no other part of this program // is using the port object. EnterCriticalSection(&port->m_csCommunicationSync); // ClearCommError() will update the COMSTAT structure and // clear any other errors. bResult = ClearCommError(port->m_hComm, &dwError, &comstat); LeaveCriticalSection(&port->m_csCommunicationSync); // start forever loop. I use this type of loop because I // do not know at runtime how many loops this will have to // run. My solution is to start a forever loop and to // break out of it when I have processed all of the // data available. Be careful with this approach and // be sure your loop will exit. // My reasons for this are not as clear in this sample // as it is in my production code, but I have found this // solutiion to be the most efficient way to do this. if (comstat.cbInQue == 0) { // break out when all bytes have been read break; } EnterCriticalSection(&port->m_csCommunicationSync); if (bRead) { bResult = ReadFile(port->m_hComm, // Handle to COMM port &RXBuff, // RX Buffer Pointer 1, // Read one byte &BytesRead, // Stores number of bytes read &port->m_ov); // pointer to the m_ov structure // deal with the error code if (!bResult) { switch (dwError = GetLastError()) { case ERROR_IO_PENDING: { // asynchronous i/o is still in progress // Proceed on to GetOverlappedResults(); bRead = FALSE; break; } default: { // Another error has occured. Process this error. port->ProcessErrorMessage("ReadFile()"); break; } } } else { // ReadFile() returned complete. It is not necessary to call GetOverlappedResults() bRead = TRUE; } } // close if (bRead) if (!bRead) { bRead = TRUE; bResult = GetOverlappedResult(port->m_hComm, // Handle to COMM port &port->m_ov, // Overlapped structure &BytesRead, // Stores number of bytes read TRUE); // Wait flag // deal with the error code if (!bResult) { port->ProcessErrorMessage("GetOverlappedResults() in ReadFile()"); } } // close if (!bRead) LeaveCriticalSection(&port->m_csCommunicationSync); // notify parent that a byte was received ::SendMessage((port->m_pOwner)->m_hWnd, WM_COMM_RXCHAR, (WPARAM)RXBuff,(LPARAM)port->m_nPortNr); } // end forever loop } // // Write a string to the port // void CSerialPort::WriteToPort(char *string) { assert(m_hComm != 0); memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer)); strcpy(m_szWriteBuffer, string); // set event for write SetEvent(m_hWriteEvent); } // // Return the output buffer size // DWORD CSerialPort::GetWriteBufferSize() { return m_nWriteBufferSize; } |
// // Return the device control block // DCB CSerialPort::GetDCB() { return m_dcb; } // // Return the communication event masks // DWORD CSerialPort::GetCommEvents() { return m_dwCommEvents; } |
// // If there is a error, give the right message // void CSerialPort::ProcessErrorMessage(char *ErrorText) { char *Temp = new char[200]; LPVOID lpMsgBuf; FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM, NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language (LPTSTR) &lpMsgBuf, 0, NULL); sprintf(Temp, "WARNING: %s Failed with the following error: \n%s\nPort: %d\n", (char*) ErrorText, lpMsgBuf, m_nPortNr); MessageBox(NULL, Temp, "Application Error", MB_ICONSTOP); LocalFree(lpMsgBuf); delete []Temp; } |