/* hexconv - A Full Ascii to Hexidecimal & Hexidecimal to Ascii Converter.
Copyright (C) 2003 Shaun Marquardt
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/

#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

#define TRUE 1
#define FALSE !TRUE

void atoh( char *input );
void htoa( char *input );

void main( void )
{
 char input[5000];

 clrscr();
 printf("1:  Convert a string to Hexidecimal\n");
 printf("2:  Convert hexidecimal to a String\n");
 printf("3:  Exit\n");
 printf("\nEnter your choice: ");

 switch(getche())
 {
  case '1':
   printf("\nEnter the string to be converted\n: ");
   gets(input);
   atoh(input);
   break;
   
  case '2':
   printf("\nEnter the hexidecimal - read the README for more info\n: ");
   gets(input);
   htoa(input);
   break;
  
  case '3': break;
  
  default:
   printf("\nThat is an invalid choice!");
   getch();
   main();
 } //end switch

 exit(0);
}

void atoh( char *input )
{
 unsigned char a;
 int x = 0, col = 0;
 int done;

 printf("String - \"%s\"\n",input);
 printf("--== Output ==--\n\n");
 printf("\"");

 done = FALSE;
 while(!done)
 {                       //Go through list of characters
  for(a=32;a<128;a++)
  {
   if(input[x] == '\0') //End of input, done.
   {
    printf("\"\n");
    done = TRUE;
    break;
   }

   if(a != input[x] && input[x] != '\0') //Not matching, continue
        continue;

   if(a == input[x] ) //Matching, print character
   {
    printf("%X",a);
    
    col++;
    if(col >= 79)
    {
     col = 0;
     printf("\n\r");
    }
    break;
   }
  } //end for

 x++; 
 } //end while
 printf("\nDone. Press the enter key to exit the program.");
 getch();
 exit(0);
} //end atoh

void htoa( char *input )
{
 unsigned char a;
 char hex[5];
 char buf[5];
 int x = 0, col = 0;
 int done;

 hex[0] = '\0';

 if( (strlen(input) % 2) != 0 )
 {
   printf("Hex characters must be entered in pairs.\n");
   getch();
   exit(1);
 }
 
 printf("Hex - \"%s\"\n",input);
 printf("--== Output ==--\n\n");
 printf("\"");

 done = FALSE;
 while(!done)
 {
   if(input[x] == '\0') //End of input, done.
   {
    printf("\"\n");
    done = TRUE;
    break;
   }

   if(input[x] == ' ') //Space character? Print out a space.
   {
    printf("%c", ' ');
    x++;
   }
   
   sprintf(hex, "%c%c", toupper(input[x]), toupper(input[x+1])); //Get Hex Char
   x+=2;
   
   for(a=32;a<128;a++)
   {                      //Go through list of characters
    sprintf(buf, "%X",a);

    if(!strcmp(buf, hex)) //Matching, print character
     printf("%c",a);
    else            //Not Matching, continue
     continue;
     
    col++;
    if(col >= 79)
    {
     col = 0;
     printf("\n\r");
    }
    break;
   } //end "a" for loop
   
 } //end while
 printf("\nDone. Press the enter key to exit the program.");
 getch();
 exit(0);
} //end htoa