一个超级简单的c++日志文件(c++11实现，跨平台）

myLog.h

#ifndef __myLog_H_
#define __myLog_H_
#include 
#include 
#include 
#include 

#include 
#include 
#include 
#include 

#define CLAMPXX(a, s, m) ((a) < (s)? (s) : ((a) > (m) ? (m) : (a)))

std::string GetName(const char * fileName);

std::string getCurrentSystemTime();

long long getCurrentMs();
// 
int LOGINIT();
// 
int LOGEnd();
// 
int LOGSetMaxSpace(int mSize);

int logWrite(char * s);

#define  LOGEM(...)  {\
                        char temp[8192] = {0};      \
						sprintf(temp, "%s", getCurrentSystemTime().c_str());  \
						sprintf(temp+strlen(temp), " %s %d ", GetName(__FILE__).c_str(), __LINE__);  \
                        sprintf(temp+strlen(temp), __VA_ARGS__); \
						sprintf(temp + strlen(temp), "\n");    \
                        printf("%s", temp);   \
						logWrite(temp); \
                    }
#endif

myLog.cpp

#include "myLog.h"
#include "GetFileName.h"
#include 
#include 
#include   
#define OS_Linux 0
#define OS_Windows 1
#define OS_iOS 2

#if OS_S==OS_Linux
#include 
#include 
#include 
#include 
#include 


#elif OS_S== OS_iOS
#include 
#include 
#include 
#elif OS_S == OS_Windows
#include 
#include 
#endif



std::string dumpRoot = "./cpplog"; //
std::mutex mux;
static FILE * fp = NULL;
int MaxLenChar = 1024 * 1024 * 3; // ,  1024 * 1024 * 5
int MaxLogNum = 5;

static int com(const void *a, const void *b)
{
    long long * p1, *p2;
    p1 = (long long *)a;  //
    p2 = (long long *)b;  //

    return *p1 > *p2 ? 1 : -1;
}


void GetAllFiles(std::string path, std::vector& files)
{
	intptr_t   hFile = 0;


#if OS_S == OS_Windows
	struct _finddata_t fileinfo;//    
	std::string p;
	if ((hFile = _findfirst(p.assign(path).append("\\*").c_str(), &fileinfo)) != -1)  //  
	{
		do
		{
			if ((fileinfo.attrib &  _A_SUBDIR))  //  
			{
				if (strcmp(fileinfo.name, ".") != 0 && strcmp(fileinfo.name, "..") != 0)  //  
				{
					files.push_back(p.assign(path).append("\\").append(fileinfo.name));
					GetAllFiles(p.assign(path).append("\\").append(fileinfo.name), files);

				}
			}
			else //   
			{
				

				files.push_back(p.assign(path).append("\\").append(fileinfo.name));
			}

		} while (_findnext(hFile, &fileinfo) == 0);

		_findclose(hFile); //  
	}
#elif OS_S == OS_Linux


	dirent * dirt;		// linux
	DIR * dir;;
	char *s[100];
	int i = 0, n = 1;
	int onePathLen = 256;
	s[0] = new  char[onePathLen];
	memset(s[0], 0, onePathLen);
	sprintf(s[0], "%s", path.c_str());
	do {
		dir = opendir(s[i]);		//
									//
		if (dir != NULL)
		{
			while ((dirt = readdir(dir)) != NULL) {     // 
														//
				if (strcmp(dirt->d_name, ".") == 0 || strcmp(dirt->d_name, "..") == 0)
					continue;
				s[n] = new  char[onePathLen];
				memset(s[n], 0, onePathLen);
				sprintf(s[n], "%s/%s", s[i], dirt->d_name);
				n++;
			}
		}
		i++;
	} while (i < n);
	for (i = 1; i < n; i++)     // 
	{
		printf("%s\n", s[i]);

		std::string temp = s[i];
		files.push_back(temp);

	}

	closedir(dir);
	while (n--) {
		//remove(s[n]);
		delete[]s[n];
	}

#endif
}


// 
void GetName(std::vector &vPath, std::vector &vName)
{
	if (vPath.size() <= 0)
	{
		printf("vPath.size <= 0");
		return;
	}
	for (int i = 0; i < vPath.size(); i++)
	{
		std::string path = vPath[i];

		int pointDot = path.find_last_of('.');

#if OS_S == OS_Windows
		int pointN = path.find_last_of('\\');
#elif OS_S == OS_Linux
		int pointN = path.find_last_of('/');
#endif

		std::string name = path.substr(pointN + 1, pointDot - pointN - 1);

		vName.push_back(name);

	}

}



static int removeOldFile(std::string &rootPath)
{

    std::vector files;

    std::vector filesNum;
    GetAllFiles(rootPath, files);

	printf("rootPath = %s files.size = %d \n", rootPath.c_str(), files.size());
    if (files.size() > MaxLogNum)
    {
        for (int i = 0; i < files.size(); i++)
        {
            int pos0 = files[i].find("LOG_");

            std::string cut = files[i].substr(pos0 + 4, files[i].size());

            char* endptr = NULL;
            long long num = std::strtoll(cut.c_str(), &endptr, 10);

            printf("cut = %s num = %lld \n", cut.c_str(), num);

            filesNum.push_back(num);

        }
        qsort(&filesNum.data()[0], filesNum.size(), sizeof(long long), com);

        // 
        printf(" delete num = %d   \n", filesNum.size() - 5);
        long long deleteNum = filesNum.size() - MaxLogNum;

        for (int i = 0; i < deleteNum; i++)
        {
            std::string logPath = rootPath + std::string("/LOG_") + std::to_string(filesNum[i]);
            printf("删除文件= %s   \n", logPath.c_str());
            remove(logPath.c_str());
        }
    }

    return 0;
}




int dump_init_temp() {

#undef FUNC_CODE
#define FUNC_CODE 0x01

	//create dump folder
#if OS_S==OS_Windows
	if (_access(dumpRoot.c_str(), 00) != 0) {
		_mkdir(dumpRoot.c_str());
#else
	if (access(dumpRoot.c_str(), 00) != 0) {
		mkdir(dumpRoot.c_str(), S_IRWXU);
#endif
	}
	return 0;
	}

int LOGINIT()
{

	dump_init_temp();

    removeOldFile(dumpRoot);

    long long currentMs = getCurrentMs();
    char currentMsStr[20];

    sprintf(currentMsStr,"%lld", currentMs);



    std::string logPath = dumpRoot + "/LOG_" + currentMsStr;


    fp = fopen(logPath.c_str(), "w+");
	if (fp == NULL)
	{
		return -1;
	}
	return 0;
}
int LOGSetMaxSpace(int mSize)
{
	MaxLenChar = mSize;
	return 0;
}

int logWrite(char * s)
{
	if (fp)
	{
		int len = ftell(fp);
		if (len > MaxLenChar)
		{
			LOGEnd();
			LOGINIT();
			return 0;
		}
		mux.lock();
		fprintf(fp, "%s", s);
		fflush(fp);
		mux.unlock();
	}

	return 0;
}

int LOGEnd()
{
	if (fp)
	{
		fflush(fp);
		fclose(fp);
		fp = 0;
	}
	return 0;
}

std::string getCurrentSystemTime()
{
	auto time_now = std::chrono::system_clock::now();
	auto tt = std::chrono::system_clock::to_time_t(time_now);
	auto duration_in_ms = std::chrono::duration_cast(time_now.time_since_epoch());
	auto duration_in_s = std::chrono::duration_cast(time_now.time_since_epoch());
	int theMs = duration_in_ms.count() - duration_in_s.count() * 1000;
	struct tm* ptm = localtime(&tt);


	char date[60] = { 0 };
	sprintf(date, "%d-%02d-%02d-%02d.%02d.%02d.%03d%",
		(int)ptm->tm_year + 1900, (int)ptm->tm_mon + 1, (int)ptm->tm_mday,
		(int)ptm->tm_hour, (int)ptm->tm_min, (int)ptm->tm_sec, theMs);
	return std::string(date);
}
long long getCurrentMs()
{
	auto time_now = std::chrono::system_clock::now();
	auto duration_in_ms = std::chrono::duration_cast(time_now.time_since_epoch());

	return duration_in_ms.count();
}
std::string GetName(const char * fileName)
{
	char temp[256] = { 0 };
	memcpy(temp, fileName, strlen(fileName) + 1);

	std::string sName = temp;

#ifdef WIN32
	int startP = sName.find_last_of("\\");
	if (startP == -1)
	{
		startP = 0;
	}
	std::string theLastName = sName.substr(startP + 1, sName.size() - startP);

#else
	int startP = sName.find_last_of("/");
	if (startP == -1)
	{
		startP = 0;
	}
	std::string theLastName = sName.substr(startP + 1, sName.size() - startP);

#endif
	return theLastName;
}

main.cpp

#include
#include "myLog.h"

int main()
{
	LOGINIT();
	for (int i = 0; i < 1000; i++)
	{
		LOGE("%f .....%d ", 12563.0 * i, i);

	}
	LOGEnd();
	getchar();
    return 0;
}

下载地址
输出log.txt
2018-10-17-19.24.27.155 main.cpp 10 0.000000 …0
2018-10-17-19.24.27.158 main.cpp 10 12563.000000 …1
2018-10-17-19.24.27.158 main.cpp 10 25126.000000 …2
2018-10-17-19.24.27.159 main.cpp 10 37689.000000 …3
2018-10-17-19.24.27.159 main.cpp 10 50252.000000 …4
2018-10-17-19.24.27.159 main.cpp 10 62815.000000 …5
2018-10-17-19.24.27.159 main.cpp 10 75378.000000 …6
2018-10-17-19.24.27.159 main.cpp 10 87941.000000 …7
2018-10-17-19.24.27.159 main.cpp 10 100504.000000 …8
2018-10-17-19.24.27.159 main.cpp 10 113067.000000 …9
2018-10-17-19.24.27.159 main.cpp 10 125630.000000 …10