statfs

/****************************************************************************@File Name: statfs.h@Author: wangzhicheng@mail: [e-mail]@Created Time: Tue 28 Feb 2017 05:15:08 PM CST   2017-03-01****************************************************************************/#ifndef STATFS_H#define STATFS_H#include <unistd.h>#include <string.h>#include <sys/stat.h>#include <dirent.h>#include <string>#include <algorithm>namespace statfs{using namespace std;enum FILETYPE{ISDIR,ISFIFO,ISCHR,// character fileISBLK,// block fileISREG,// regular fileISUNKNOWN// unknown };class Statfs{public:/* * @brief judge whether a process have permission to the file * @path the full path of targeted file * @perm the combination of rwx "r" -- read "w" -- write "x" -- execute * such as "rx" "rxw" "wr" "rwx" and so on  * @return true if read is ok * */static bool Permit(const string &path, const string &perm);/* * @brief get the size of file * */static off_t FileSize(const string &path);/* * @brief get the size of dir * */static off_t DirSize(const string &path);/* * @brief get the type of file * */static FILETYPE FileType(const string &path);};}#endif/****************************************************************************@File Name: statfs.cpp@Author: wangzhicheng@mail: [e-mail]@Created Time: Tue 28 Feb 2017 05:15:08 PM CST   2017-03-01****************************************************************************/#include "statfs.h"namespace statfs{bool Statfs::Permit(const string &path, const string &perm){struct stat buf;bool perms[3] = {0};bool permits[3] = {0};const static mode_t user_modes[3] = {S_IRUSR, S_IWUSR, S_IXUSR};const static mode_t group_modes[3] = {S_IRGRP, S_IWGRP, S_IXGRP};const static mode_t other_modes[3] = {S_IROTH, S_IWOTH, S_IXOTH};if(perm.size() > 3 || perm.size() <= 0) return false;if(stat(path.c_str(), &buf)) return false;if(!getuid()) return true;// root // get the permissions from the perm argumentfor_each(begin(perm), end(perm), [&perms](char ch){switch(ch){case 'r':case 'R':if(!perms[0]) perms[0] = true;break;case 'w':case 'W':if(!perms[1]) perms[1] = true;break;case 'x':case 'X':if(!perms[2]) perms[2] = true;break;}});// check the buf and update permitsfor(int i = 0;i < 3;i++){if(!perms[i]) continue;if(buf.st_uid == geteuid()){permits[i] = buf.st_mode & user_modes[i];continue;}if(buf.st_gid == getegid())  {permits[i] = buf.st_mode & group_modes[i];continue;}permits[i] = buf.st_mode & S_IROTH;}// judgefor(int i = 0;i < 3;i++){if(!perms[i]) continue;if(!permits[i]) return false;}return true;}/* * @brief get the size of file * */off_t Statfs::FileSize(const string &path){struct stat buf;  if(stat(path.c_str(), &buf)) return -1;return buf.st_size;  }/* * @brief get the type of file * */FILETYPE Statfs::FileType(const string &path){struct stat buf;  if(stat(path.c_str(), &buf)) return ISUNKNOWN;if(S_ISDIR(buf.st_mode)) return ISDIR;if(S_ISREG(buf.st_mode)) return ISREG;if(S_ISFIFO(buf.st_mode)) return ISFIFO;if(S_ISCHR(buf.st_mode)) return ISCHR;  if(S_ISBLK(buf.st_mode)) return ISBLK;return ISUNKNOWN;  }/* * @brief get the size of dir * */off_t Statfs::DirSize(const string &path){off_t total = 0;DIR *dp = nullptr;struct dirent *dirp = nullptr;string newpath;static const string STR = "/"; if(!(dp = opendir(path.c_str()))) {closedir(dp);return 0;}while((dirp = readdir(dp))) {if(!strcmp(dirp->d_name, ".") || !strcmp(dirp->d_name, "..")) continue;// generate a new pathnewpath = path;if('/' != newpath[newpath.size() - 1]) newpath += STR;// judge the last characternewpath += dirp->d_name;// is directoryif(ISDIR == Statfs::FileType(newpath)){total += DirSize(newpath);}else{total += FileSize(newpath);}}return total;}}/****************************************************************************@File Name: test.cpp@Author: wangzhicheng@mail: [e-mail]@Created Time: Tue 28 Feb 2017 05:37:13 PM CST  2017-03-01****************************************************************************/#include "statfs.h"#include <iostream>using namespace statfs;int main(){//setuid(1000);//cout << Statfs::Permit("/var/log/TrendMicro/SProtectLinux/System.20170218.0001", "rxw") << endl;//cout << Statfs::FileSize("/var/log/TrendMicro/SProtectLinux/System.20170218.0001") << endl;//cout << Statfs::FileSize("/opt/TrendMicro/SProtectLinux/Product.ini") << endl;//cout << Statfs::FileType("/opt") << endl;cout << Statfs::DirSize("/opt") << endl;return 0;}