X-Encrypter

[dhuan]

After reading a tutorial on XOR encryption at cplusplus.com I decided to code
this super program called X-Encrypter, just so I can practice what I've learned
from tutorials.
This is what it does: it can create xor-encrypted text files from scratch,
it can read xor-encrypted text files, and it also allows the user to
set the encryption key.
This is what ive come up with so far:

#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <fstream>
#include <string>

using namespace std;

string key="k";

void commandScreen(int& command);
void readXorFile(fstream& file);
void newXorFile(fstream& file);
void setKey(string& key);
void encrypt(string str, string& newStr);

int main()
{
    int c=0; // stores command chosen by user
    fstream file;

    do
    {
         commandScreen(c);

         switch(c)
         {
              case 1:
              readXorFile(file);
              break;

              case 2:
              newXorFile(file);
              break;

              case 3:
              setKey(key);
              break;
         }

    }
    while(c != 0);

    cout<<"\n\nAstalavista.\n";
}


void commandScreen(int& command)
{
     cout<<"\n*************************************************\n**************** X-ENCRYPTER 0.1 ****************\n*************************************************\n";

     cout<<"\n1-> READ ENCRYPTED TEXT"<<endl;
     cout<<"2-> NEW ECRYPTED TEXT"<<endl;
     cout<<"3-> SET ENCRYPTION KEY"<<endl;
     cout<<"\nCOMMAND: ";
     cin>>command;
}

void setKey(string& key)
{
    cout<<"\KEY: ";
    cin>>key;
    cout<<"Key set to '"<<key<<"'"<<endl;
    system("PAUSE");

}

void readXorFile(fstream& file)
{
    char filePath[100];
    string encTxt;
    string result;
    cout<<"\nENCRYPTED FILE: ";
    cin>>filePath;
    file.open(filePath,ios::in);
    if(file.is_open())
    {
        file>>encTxt;
        encrypt(encTxt,result);
        cout<<"\nResult: "<<result<<"\n";
        system("PAUSE");
    }
    else
    {
        cout<<"\nThere's no such file '"<<filePath<<"'\n";
        system("PAUSE");
    }
    file.close();
}

void newXorFile(fstream& file)
{
    char filePath[100]; // it wont allow me to use string on fstream::open()
    cout<<"\nNEW FILE: ";
    cin>>filePath;

    file.open(filePath,ios::out | ios::binary);
    //binary because it doesnt need to be txt file

    if(file.is_open())
    {
        string txt;
        string enc; // stores encrypted text
        cout<<"TEXT: ";
        cin>>txt;
        encrypt(txt,enc);
        file<<enc;
        cout<<"\nEncrypted text stored into '"<<filePath<<"'\n";
        system("PAUSE");
    }
    else
    {
       cout<<"Couldn't create file...\n";
       system("PAUSE");
    }

    file.close();

}

void encrypt(string str, string& newStr)
{
    newStr=str;
    int strLen = str.length() - 1;
    int keyLen = key.length();

    for(int x=0; x <= strLen; x++)
    {
        newStr[x] = str[x]^key[x % keyLen];
    }
}

Now these are the issues i've bumped into so far:

1-)No matter how simple it might seem to be, the key setter function never works
right, example: the default key is 'k', but when manually changing it to 'k' it works differently.

2-)When creating a new file, typing the text to be saved, if you enter a spacebar the program will loop infinitely, i dont know why

3-)Somehow I cant figure out how to make the fstream.open() function work with string, I even tried type casting, but it doenst work...

4-)When choosing to read a encrypted file, when it tries to read the character 'a' it stops reading...

[Florian]

3-)Somehow I cant figure out how to make the fstream.open() function work with string, I even tried type casting, but it doenst work...

See this bit of code:

std::string filename("long\path\to\file.txt");

const char* filename_str = filename.c_str();

fstream file(filename_str);

[dhuan]

Bump