strtok2.cc

      /* $Id: strtok2.cc,v 1.2 2001/11/01 20:01:52 eric Exp $ */
      
      /* SYNOPSIS
       *
       * strtok2.cc - strtok2
       *
       * The strtok2() function splits the string pointed to by the buf 
       * parameter into a sequence of tokens, each of which is delimited by a
       * byte equal to one of the bytes in the delim_list parameter.  That 
       * byte is then copied into the delim_storage variable.
       *
       * strtok2() can be called repeatedly to extract all of the tokens in 
       * the string.  When the final token is reached, or if there are no
       * tokens to return, strtok2() will return a NULL pointer.
       *
       *
       * REVISION HISTORY
       *
       * $Log: strtok2.cc,v $
       * Revision 1.2  2001/11/01 20:01:52  eric
       * Corrected error detecting end of string and erroneous return of NULL
       *
       * Revision 1.1  2001/10/23 21:30:02  eric
       * Initial revision
       *
       */
      
      #include <stdio.h>
      #include <string.h>
      #include <stdlib.h>
      #include "strtok2.h"
      
      /*  Function strtok2()
       *  --------------------------------------------------------------------
       *
       *    strtok2() aims to be a threadsafe version of strtok(). 
       *    If there are multiple trailing delimiters, this implementation
       *    will return only the first one, and will then ignore the next
       *    group of delimiters.
       *
       *    PARAMETERS:
       *      buf           - the string to tokenize
       *      delim_storage - location in which to store delimiter
       *      delim_list    - list of delimiters
       *
       *    RETURNS
       *      char *        - a single string extracted from buffer
       *
       */
      
      char *strtok2( char **buf, char *delim_storage, char *delim_list )
      {
         int index = 0;
         char *token;
      
         /* skip adjacent delimiters */
      
      
         while ( ( index == 0 ) && ( **buf != '\0' ) )
         {
            index = strcspn( *buf, delim_list );
            *buf += ( index + 1 );
         }
      
         if ( *( *buf - ( index + 1 ) ) == '\0' )
            return NULL;
      
      
         token = (char *)malloc( sizeof( char ) * ( index + 1 ) );
         strncpy( token, *buf - ( index + 1 ), index );
         token[ index ] = '\0';
         *delim_storage = *( *buf - 1 ); 
      
         return token; 
      }