Access violation (Segmentation fault) raised in your program.

I received this error when I ran my program after compiling it. I can't find the error in my code.

main.cpp

/*
  Main.cpp source file. Main module.
  Copyright 2009 (GNU CC Licence) Madcow Deity Productions
*/

#include <cstdlib>
#include <iostream>
#include "System.hpp"
using namespace std;

System __main('C');
int RuleDialog();


int main(int argc, char *argv[])
{
    //Init
    system("title Hosts Organizer 1.0.0 by Madcow Deity Productions");
    bool exit = false;
    
    //PRG
    cout << "Welcome to Hosts Organizer by Madcow Deity Productions\n    ";
    system("pause");
    system("cls");
    
    //Main loop
    while(exit = false)
    {
               int in;
        system("cls");
        cout << "Main Menu\n______________________\n\n\n";
        cout << " [1] See current hosts file\n";
        cout << " [2] Set rules\n";
        cout << " [3] Close\n\n";
        
        cin >> in;
        switch(in)
        {
                  case 1: 
                       __main.CurrentHostsFile();
                  break;
                  case 2:
                       __main.Set(RuleDialog());
                  break;
                  case 3:
                       exit = true;
                  break;
                  default:
                          cout << "Error" << endl;
                  break;
                       
        }
    }
    
    
    return EXIT_SUCCESS;
}

int RuleDialog()
{
    system("cls");
         int in;
    cout << "Set rules\n_____________________\n\n\n";
    
    cout << " [1] Reset\n";
    cout << " [2] Light - includes: Facebook, Twitter, Myspace\n";
    cout << " [3] Full - includes: Social Networking sites and Photosharing sites\n\n";
    
    cin >> in;
    if(in == 1 || in == 2 || in == 3)
          return in;
    else 
          cout << "ERROR WITH INPUT" << endl;
          system("pause");
}

System.cpp

#include "System.hpp"

//Constructors

System::System(char drive_in)
{
     drive = drive_in;
}

bool System::Set(int type)
{
     system("cls");
     /*
     Type 2
     Includes: Facebook and Myspace + TWITTER
     
     IPs:
         myspace.com    127.0.0.1
         facebook.com    127.0.0.1
         twitter.com 127.0.0.1
         
     */
     /*
     Type 3:
     Includes: Facebook, Myspace, Twitter, Hi5, Flickr, PhotoBucket.
     
     IPs:
         www.facebook.com 127.0.0.1
         www.myspace.com 127.0.0.1
         www.twitter.com 127.0.0.1
         www.hi5.com 127.0.0.1
         www.flickr.com 127.0.0.1
         www.photobucket.com 127.0.0.1
     */
     
     //Type Write
     vector <string> webaddr;
     bool wrote = false;
     //Reset
     string reset = "localhost 127.0.0.1\n";
     
     switch( type )
     {
             case Light:
                  {
                        system("cls");
                        //Webaddr set
                        webaddr.push_back("www.facebook.com 127.0.0.1\n");
                        webaddr.push_back("www.myspace.com 127.0.0.1\n");
                        webaddr.push_back("www.twitter.com 127.0.0.1\n");
                        //Display
                        std::cout << "Modifying hosts file..\n";
                        
                        wrote = Write(webaddr);
                        if(wrote = false)
                        {
                            std::cout << "Error writing to hosts file.\nAn other program may be using it.\n";
                            system("pause");
                            return false;
                        }
                        else
                        {
                            std::cout << "Wrote to host file correctly\n";
                            system("pause");
                        }
                        return true;
                            
                  }
                  break;
             case Full:
                  {
                        
                        //Webaddr set
                        webaddr.push_back("www.facebook.com 127.0.0.1\n");
                        webaddr.push_back("www.myspace.com 127.0.0.1\n");
                        webaddr.push_back("www.twitter.com 127.0.0.1\n");
                        webaddr.push_back("www.hi5.com 127.0.0.1\n");
                        webaddr.push_back("www.flickr.com 127.0.0.1\n");
                        webaddr.push_back("www.photobucket.com 127.0.0.1\n");
                        //Display
                        std::cout << "Modifying hosts file..\n";
                        
                        //Stuff
                        wrote = Write(webaddr);
                        if(wrote = false)
                        {
                            std::cout << "Error writing to hosts file.\nAn other program may be using it.\n";
                            system("pause");
                            return false;
                        }
                        else
                        {
                            std::cout << "Wrote to host file correctly\n";
                            system("pause");
                        }
                        return true;
                        
                  }
                  break;
                  case Reset:
                   {
                       ofstream myfile (drive + ":\\WINDOWS\\system32\\drivers\\etc\\hosts");
                       if (myfile.is_open())
                       {
                         myfile << reset;
                         myfile.close();
                       }
                       else std::cout << "Unable to open file";
                         
                   }
                   break;
  
     }
     return true;
     
}


bool System::Write(vector <string> webaddr)
{
     //Prepare to write.
     ofstream myfile (drive + ":\\WINDOWS\\system32\\drivers\\etc\\hosts", ios::out);
     
     //Write
     if (myfile.is_open())
     {
       for(int i = 0; i < webaddr.size(); i++)
       {
               myfile << webaddr[i] << "\n";
       }
       myfile.close();
     }
     else return false;
     return true;
}

bool System::CurrentHostsFile()
{
     system("cls");
     
     std::cout << "                 Hosts file\n";
     std::cout << "________________________________________________\n\n\n";
     
     //Read
     string line;
     ifstream myfile (drive + ":\\WINDOWS\\system32\\drivers\\etc\\hosts", ios::in);
      if (myfile.is_open())
      {
        while (! myfile.eof() )
        {
          getline (myfile,line);
          std::cout << line << std::endl;
        }
        system("pause");
      }
      else return false;
      return true;
}

System.hpp

/*
  System class
*/
#include <string>
#include <vector>
#include <fstream>
#include <cstdlib>
#include <iostream>

using namespace std;
enum eWriteType
{
     Reset,
     Light,
     Full
};

class System
{
      private:
        char drive;
      public:
        System(char drive_in); //Initilization (with specific drive)
        bool Set(int type); //Write to host w/o Manual adding (presets)
        bool Write(vector <string> webaddr);
        
        bool CurrentHostsFile();           
};

I know its not perfectly correct but I'll fix it later so don't flame me. Just help me with the compilation error.

Edited 7 Years Ago by argio: n/a

I can't get the code to seg fault but I am running it on linux.

However you have many instances of code like: if (wrote=false) and similar Note: you only have ONE =. This is certainly wrong. Consider the line above. It would set wrote to false and then never execute the code in the error block. PLEASE (a) get a compiler that gives warning messages, (b) FIX THEM. -- I almost missed the == error in the storm of other warning messages.

If you are still getting seg-faults can you suggest the input information you typed to get that error??

You know the basics, don't use using namespace std; , don't name stuff like System etc, that is so easy to miss-type, don't mix '\n' and std::endl; [use the latter], don't pass things by value that would be better by const reference. e.g webaddr to System::Write( ). You will have less problems if you code to these standards, it then becomes instinctive.

Edited 7 Years Ago by StuXYZ: n/a

I'm using Dev C++? I fixed those errors and yet it still compiles fine and instantly closes with the segmentation fault error after compiling.

well then the first thing to do is to find out if you get to your first system command. Put a std::cout<<"TEST"<<std::endl; exit(1) at line 17 of your main. Then see if you get that without a seg fault.

If you don't then you have an error in the constructor of System.
If not then it maybe the system command and so on. A debugger can help here lots.

This article has been dead for over six months. Start a new discussion instead.