src/misc.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2008-2009 by Andrzej Rybczak                            *
   3  *   electricityispower@gmail.com                                          *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
  19  ***************************************************************************/
  20
  21 #include <cerrno>
  22 #include <cstdlib>
  23 #include <cstring>
  24 #include <fstream>
  25 #include <iostream>
  26 #include <openssl/evp.h>
  27 #include <pwd.h>
  28
  29 #include "configuration.h"
  30 #include "misc.h"
  31
  32 size_t write_data(char *buffer, size_t size, size_t nmemb, void *data)
  33 {
  34         size_t result = size * nmemb;
  35         static_cast<std::string *>(data)->append(buffer, result);
  36         return result;
  37 }
  38
  39 void ChangeToUser()
  40 {
  41         if (Config.dedicated_user.empty() || getuid() != 0)
  42                 return;
  43
  44         passwd *userinfo;
  45         if (!(userinfo = getpwnam(Config.dedicated_user.c_str())))
  46         {
  47                 std::cerr << "user " << Config.dedicated_user << " not found!\n";
  48                 exit(1);
  49         }
  50         if (setgid(userinfo->pw_gid) == -1)
  51         {
  52                 std::cerr << "cannot set gid for user " << Config.dedicated_user << ": " << strerror(errno) << std::endl;
  53                 exit(1);
  54         }
  55         if (setuid(userinfo->pw_uid) == -1)
  56         {
  57                 std::cerr << "cannot change to uid of user " << Config.dedicated_user << ": " << strerror(errno) << std::endl;
  58                 exit(1);
  59         }
  60         Config.user_home_folder = userinfo->pw_dir ? userinfo->pw_dir : "";
  61 }
  62
  63 bool Daemonize()
  64 {
  65         if (daemon(0, 0) < 0)
  66                 return false;
  67
  68         std::ofstream f(Config.file_pid.c_str(), std::ios_base::trunc);
  69         if (f.is_open())
  70         {
  71                 pid_t pid = getpid();
  72                 f << pid;
  73                 f.close();
  74                 return true;
  75         }
  76         else
  77                 return false;
  78 }
  79
  80 void WriteCache(const std::string &s)
  81 {
  82         std::ofstream f(Config.file_cache.c_str(), std::ios::app);
  83         if (f.is_open())
  84         {
  85                 f << s << std::endl;
  86                 f.close();
  87         }
  88 }
  89
  90 void Log(LogLevel ll, const char *format, ...)
  91 {
  92         if (Config.log_level < ll)
  93                 return;
  94         FILE *f = fopen(Config.file_log.c_str(), "a");
  95         if (!f)
  96         {
  97                 perror("Cannot open log file!\n");
  98                 exit(1);
  99         }
 100         fprintf(f, "[%s] ", DateTime().c_str());
 101         va_list list;
 102         va_start(list, format);
 103         vfprintf(f, format, list);
 104         va_end(list);
 105         fprintf(f, "\n");
 106         fclose(f);
 107 }
 108
 109 void IgnoreNewlines(std::string &s)
 110 {
 111         for (size_t i = s.find("\n"); i != std::string::npos; i = s.find("\n"))
 112                 s.replace(i, 1, "");
 113 }
 114
 115 std::string md5sum(const std::string &s)
 116 {
 117         unsigned char md_value[EVP_MAX_MD_SIZE];
 118         unsigned int md_len;
 119
 120         EVP_MD_CTX mdctx;
 121         EVP_DigestInit(&mdctx, EVP_md5());
 122         EVP_DigestUpdate(&mdctx, s.c_str(), s.length());
 123         EVP_DigestFinal_ex(&mdctx, md_value, &md_len);
 124         EVP_MD_CTX_cleanup(&mdctx);
 125
 126         char result[md_len*2+1];
 127         for (unsigned i = 0; i < md_len; i++)
 128                 sprintf(&result[i*2], "%02x", md_value[i]);
 129         result[md_len*2] = 0;
 130
 131         return result;
 132 }
 133
 134 std::string DateTime()
 135 {
 136         static char result[32];
 137         time_t raw;
 138         tm *t;
 139         time(&raw);
 140         t = localtime(&raw);
 141         result[strftime(result, 31, "%Y/%m/%d %X", t)] = 0;
 142         return result;
 143 }
 144
 145 int StrToInt(const std::string &s)
 146 {
 147         return atoi(s.c_str());
 148 }
 149