C++ 日志 log

原文来自：http://blog.sina.com.cn/s/blog_59b6af6901010nfh.html

修改Shenzhen 2016-9-10   把strypy、strcat等改成安全的strycpy_s、strycat_s等

ps：这个log功能过于简陋，凑合看着吧。

//可按日期生成多个日志， 还可分年月日频率生成文件名//这个代码我用工业现场24X7值守的程序纪录各种信息， 简单易用;//一般用一个全局日志对象， 有临界排斥可以多线程安全使用。//有两个类//class LogFile;//用户定义日志文件名//class LogFileEx;//有日志文件名自动生成功能 , 可分年月日频率生成文件名, 可指定日志存放的目录//LogFile gLog("My.Log");//gLog.Log("test", 4);//记录日志//gLog.Log("系统启动");//LogFileEx gLog(".", LogFileEx :: YEAR);//一年生成一个日志文件//LogFileEx gLog(".//Log", LogFileEx :: MONTH);//一月生成一个日志文件//LogFileEx gLog(".//Log", LogFileEx :: DAY);//一天生成一个日志文件//注意日志所属目录创建失败会自动退出， 请注意目录的合法性， 文件生成频率看情况掌握//24小时运行的程序可以每天生成一个日志文件， 以免内容过多#ifndef _LOGFILE_H#define _LOGFILE_H#include <assert.h>#include <time.h>#include <stdio.h>#include <windows.h>class LogFile{public:LogFile(const char *szFileName = "Log.log"); //设定日志文件名virtual ~LogFile();const char * GetFileName(){ return _szFileName; }void SetFileName(const char *szName); //修改文件名， 同时关闭上一个日志文件bool IsOpen() { return _hFile != INVALID_HANDLE_VALUE; }void Close();void Log(LPCVOID lpBuffer, DWORD dwLength); //追加日志内容void Log(const char *szText){ Log(szText, strlen(szText)); }protected:CRITICAL_SECTION _csLock;char _szFileName[MAX_PATH + 1];HANDLE _hFile;bool OpenFile(); //打开文件， 指针到文件尾DWORD Write(LPCVOID lpBuffer, DWORD dwLength);virtual void WriteLog( LPCVOID lpBuffer, DWORD dwLength); //写日志, 可以扩展修改void Lock()  { ::EnterCriticalSection(&_csLock); }void Unlock() { ::LeaveCriticalSection(&_csLock); }private://屏蔽函数LogFile(const LogFile&);LogFile&operator = (const LogFile&);};class LogFileEx : public LogFile{public:enum LOG_TYPE{YEAR = 0, MONTH = 1, DAY = 2};LogFileEx(const char *szPath = ".", LOG_TYPE iType = MONTH);~LogFileEx();const char * GetPath(){ return _szPath; }void Log(LPCVOID lpBuffer, DWORD dwLength);void Log(const char *szText){ Log(szText, strlen(szText)); }protected:char _szPath[MAX_PATH + 1];char _szLastDate[20];int _iType;void SetPath(const char *szPath);private://屏蔽函数LogFileEx(const LogFileEx&);LogFileEx&operator = (const LogFileEx&);};#endif

#include "stdafx.h"#include "Logfile.h"//-----------------------------------------------------------------------------------------LogFile::LogFile(const char *szFileName)//设定日志文件名{_hFile = INVALID_HANDLE_VALUE;::InitializeCriticalSection(&_csLock);SetFileName(szFileName);}//-----------------------------------------------------------------------------------------LogFile::~LogFile(){::DeleteCriticalSection(&_csLock);Close();}//-----------------------------------------------------------------------------------------void LogFile::SetFileName(const char *szName)//修改文件名， 同时关闭上一个日志文件{Close();memset(_szFileName, 0, MAX_PATH + 1);strcpy_s(_szFileName, MAX_PATH + 1, szName);}//-----------------------------------------------------------------------------------------bool LogFile::OpenFile()//打开文件， 指针到文件尾{if(IsOpen())return true;if(strcmp(_szFileName, "") == 0)return false;_hFile =  CreateFile(_szFileName, GENERIC_WRITE,FILE_SHARE_READ | FILE_SHARE_WRITE,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL );if(!IsOpen() && GetLastError() == 2)//打开不成功， 且因为文件不存在， 创建文件_hFile =  CreateFile(_szFileName, GENERIC_WRITE,FILE_SHARE_READ | FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL ); if(IsOpen())SetFilePointer(_hFile, 0, NULL, FILE_END);return IsOpen();}//-----------------------------------------------------------------------------------------DWORD LogFile::Write(LPCVOID lpBuffer, DWORD dwLength){DWORD dwWriteLength = 0;if(IsOpen())WriteFile(_hFile, lpBuffer, dwLength, &dwWriteLength, NULL);return dwWriteLength;}//-----------------------------------------------------------------------------------------void LogFile::WriteLog( LPCVOID lpBuffer, DWORD dwLength)//写日志, 可以扩展修改{char temp[21] = {0};DWORD dwWriteLength;if(IsOpen()){time_t now;time(&now);tm timeInfo;localtime_s(&timeInfo, &now); //转换成tm结构strftime(temp, sizeof(temp), "%Y-%m-%d %H:%M:%S", &timeInfo);WriteFile(_hFile, "\xd\xa#-----------------------------", 32, &dwWriteLength, NULL);WriteFile(_hFile, temp, 19, &dwWriteLength, NULL);WriteFile(_hFile, "-----------------------------#\xd\xa", 32, &dwWriteLength, NULL);WriteFile(_hFile, lpBuffer, dwLength, &dwWriteLength, NULL);WriteFile(_hFile, "\xd\xa", 2, &dwWriteLength, NULL);FlushFileBuffers(_hFile);}}//-----------------------------------------------------------------------------------------void LogFile::Close(){if(IsOpen()){CloseHandle(_hFile);_hFile = INVALID_HANDLE_VALUE;}}//-----------------------------------------------------------------------------------------void LogFile::Log(LPCVOID lpBuffer, DWORD dwLength)//追加日志内容{assert(lpBuffer);__try{Lock();if(!OpenFile())return;WriteLog(lpBuffer, dwLength);}__finally{Unlock();} }//LogFileEx**********************************************************************************LogFileEx::LogFileEx(const char *szPath, LOG_TYPE iType){memset(_szPath, 0, sizeof(_szPath));SetPath(szPath);_iType = iType;memset(_szLastDate, 0, sizeof(_szLastDate));}//---------------------------------------------------------------------------------LogFileEx::~LogFileEx(){}//---------------------------------------------------------------------------------void LogFileEx::Log(LPCVOID lpBuffer, DWORD dwLength){assert(lpBuffer);;static const char format[3][10] = {"%Y", "%Y-%m", "%Y%m%d"};__try{Lock();char temp[20] = {0};time_t now = time(NULL);tm timeInfo;localtime_s(&timeInfo, &now); //转成tm结构strftime(temp, sizeof(temp), format[_iType], &timeInfo);if(strcmp(_szLastDate, temp) != 0)//更换文件名{int len = sizeof(_szFileName);strcpy_s(_szFileName, len, _szPath); len -= strlen(_szPath);strcat_s(_szFileName, len, "//"); len -= 2;strcat_s(_szFileName, len, temp); len -= sizeof(temp);strcat_s(_szFileName, len, ".log"); len -= 4;strcpy_s(_szLastDate, sizeof(_szLastDate), temp);Close();}if(!OpenFile())return;WriteLog(lpBuffer, dwLength);}__finally{Unlock();}}//---------------------------------------------------------------------------------void LogFileEx::SetPath(const char *szPath){assert(szPath);WIN32_FIND_DATA wfd;char temp[MAX_PATH + 1] = {0};if(FindFirstFile(szPath, &wfd) == INVALID_HANDLE_VALUE && CreateDirectory(szPath, NULL) == 0){strcpy_s(temp, sizeof(temp), szPath);strcat_s(temp, sizeof(temp), " Create Fail. Exit Now! Error ID :");_ltoa_s(GetLastError(), temp + strlen(temp), 20, 10);MessageBox(NULL, temp, "Class LogFileEx", MB_OK);exit(1);}else{GetFullPathName(szPath, MAX_PATH, temp, NULL);strcpy_s(_szPath, sizeof(_szPath), temp);}}

// Main.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include "Common/Logfile.h"int _tmain(int argc, _TCHAR* argv[]){LogFileEx log("../Debug/Logfiles");for (int i=0; i<1000000; ++i)log.Log("4646456015555555555555555555555555555555555555");printf("已完成");getchar();return 0;}