Samples/Tokenizer/tokenizer.cpp at master · r2d2Proton/Samples · GitHub

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/*----------------------------------------------------------------------------+
|       Name:  Jerome Richards                                                |
|     Course:  CNS-1250 Section F01                                           |
| Instructor:  Dr. Afsaneh Minaie                                             |
|                                                                             |
|       File:  tokenizer.cpp                                                  |
|                                                                             |
|    Purpose:  String Tokenizer implementation                                |
+----------------------------------------------------------------------------*/
#include "tokenizer.h"

#define NULL    0

/**
 * Purpose:  Overloaded constructor
 *
 *      Parameters:  theString      a pointer to a NULL terminated character
 *                                  array
 *
 *                   theDelimiter   the delimiting character for tokens
*/
StringTokenizer::StringTokenizer( char* theString, char theDelimiter )
{
   itsString = NULL;
   itsDelimiter = ' ';

   if( theString )
   {
      itsString = theString;
      itsDelimiter = theDelimiter;
   }
}


/**
 * Purpose:  Returns the next token from the character stream
 *
 *      Parameters:  none
 *  Pre-conditions:  none
 * Post-conditions:  none
 *
 *        Returns :  a character pointer to the next token and
 *                   NULL if no other tokens exist in the stream
*/
char* StringTokenizer::next()
{
   char* token = NULL;

   // make sure that a valid pointer is being used
   if( itsString )
   {
      // skip past any delimiter characters BUT not past the NULL terminator
      while( *itsString == itsDelimiter && *itsString )
         itsString++;

      // if there is a token - process it
      if( *itsString )
      {
         // save the new starting point
         token = itsString;

         // Look for the end of the token and NULL terminate it
         while( *itsString && *itsString != itsDelimiter )
            itsString++;

         if( *itsString )
         {
            // if not at the NULL - terminate the token
            *itsString = NULL;

            // and Prepare for next token
            itsString++;
         }
      }
      else
      {
         // otherwise inform the caller there are no more tokens
         itsString = NULL;
      }
   }

   return token;
}