linux系统中c++写日志文件功能分享

简化了glog，只保留了写日志文件的功能，只是改写了linux版本，win版本未改写，可以用
LOG(INFO)<< 输出日志
也可用LOG_IF(INFO,condition)<<输出日志
也可直接调用日志类Logger::GetInstance().Error 等方式写日志
初始化时调用 InitLogging(argv[0],INFO,"./log/test");
第一个参数是路径，第二个参数是最低日志级别，第三个参数表示日志文件的前缀和文件夹

FileHelper.h
#ifndef FILEHELPER_H_
#define FILEHELPER_H_
#include <string>
#include <vector>
#include <fstream>
#include <stdio.h>
#ifdef _WIN32
#include <direct.h>
#include <io.h>
#else
#include <stdarg.h>
#include <sys/stat.h>
#endif

namespace FrameWork {
#ifdef _WIN32
#define ACCESS _access
#define MKDIR(a) _mkdir((a))
#else
#define ACCESS access
#define MKDIR(a) mkdir((a),0755)
#endif

class FileHelper {
public:
 static bool save(const std::string filename, std::string& content)
 {
        FILE *file = fopen(filename.c_str(), "wb");

        if (file == NULL)
            return false;
  fwrite(content.c_str(),sizeof(char),content.size(),file);
  fclose(file);
  return true;
 }

    // used to open binary file
    static bool open(const std::string filename, std::string& content)
    {
        FILE *file = fopen(filename.c_str(), "rb");

        if (file == NULL)
            return false;

        fseek(file, 0, SEEK_END);
        int len = ftell(file);
  rewind(file);
  content.clear();
        char *buffer = new char[len];
        fread(buffer, sizeof(char), len, file);
        content.assign(buffer, len);
        delete []buffer;

  //int nRead;
  //content.clear();
  //char buffer[80];
  //while(!feof(file)){
  // nRead = fread(buffer,sizeof(char),sizeof(buffer),file);
  // if(nRead > 0){
  //  content.append(buffer);
  // }
  //}
        fclose(file);
        return true;
    }

    // used to open text file
    static bool open(const std::string file_name, std::vector<std::string>& lines)
    {
        std::ifstream file(file_name.c_str(), std::ios::in);
        if (!file)
        {
            return false;
        }

        lines.clear();
        char buffer[BUFFER_SIZE];

        while (file.getline(buffer, BUFFER_SIZE, '\n'))
        {
            lines.push_back(buffer);
        }

        return true;
    }
    static bool CreateDir(const char *pszDir)
    {
     size_t i = 0;
     size_t iRet;
     size_t iLen = strlen(pszDir);
     char* buf=new char[iLen+1];
     strncpy(buf,pszDir,iLen+1);
     for (i = 0;i < iLen;i ++) {
      if (pszDir[i] == '\\' || pszDir[i] == '/') {
       buf[i] = '\0';
       //如果不存在,创建
       iRet = ACCESS(buf,0);
       if (iRet != 0) {
        iRet = MKDIR(buf);
        if (iRet != 0) {
         delete[] buf;
         return false;
        }
       }
       //支持linux,将所有\换成/
       buf[i] = '/';
      }
     }
     delete[] buf;
     return true;
    }

private:

    enum { BUFFER_SIZE = 3000 };

};

} /* namespace FrameWork */
#endif /* FILEHELPER_H_ */
[/code]

Logger.cpp

static void InitPaths(const char* filename,const char* destFolder)
{
 memset(_appName,0,MaxFilePathLen);
 memset(_appFolder,0,MaxFilePathLen);
 memset(_destFolder,0,MaxFilePathLen);
 memset(_destPrefix,0,MaxFilePathLen);

 strcpy(_appName,filename);
 int len = strlen(filename),lend;
 int pos = len-1,posd,start;
 while(pos >0 && filename[pos] != PathSplitChar)
  pos--;
 strncpy(_appFolder,filename,pos+1);
 lend = strlen(destFolder);
 posd = lend-1;
 if(destFolder[lend-1] != PathSplitChar) {
  //has prefix
  while(posd >0 && destFolder[posd] != PathSplitChar)
   posd--;
 }
 if(destFolder[0] == '.' && destFolder[1] == PathSplitChar){
  strncpy(_destFolder,filename,pos+1);
  start = 2;
 } else{
  pos = 8;
  strcpy(_destFolder,_defaltFolder);
  if(destFolder[0] != PathSplitChar){