boost.cpp

/*
 * =====================================================================================
 *       Filename:  boost.cpp
 *    Description:  Converts two K objects to unsigned chars.
 *                  Compares a regex expression to a string
 *                  Boost was selected as the highest performing regex library therefore
 *                  further error catching is implemented
 *
 *        Version:  2.0
 *        Created:  04/04/12 15:03:03
 *       Compiler:  g++ -static -fPIC -shared -I/usr/local/boost_1_49_0 boost.cpp -o
 *                  boost.so libs/libboost_regex.a
 *
 *         Author:  Oliver Fletcher (ttolf@lboro.ac.uk)
 *     University:  Loughborough University
 *
 * =====================================================================================
 */

#include <boost/regex.hpp>
#include "../k.h"
#include <iostream>
using namespace std;

int ERROR = 0;

/*
 * ===  FUNCTION  ======================================================================
 *         Name:  makeString
 *  Description:  Converts a K object into an unsigned char
 *                Checks that the K object is the correct type else return an error
 *       Inputs:  item -> K object of type string (10h)
 *      Returns:  str1 -> String of type unsigned char
 * =====================================================================================
 */
string makeString(K item)
{
  int sz = item->n;
  int tp = item->t;
  unsigned char *str;
  char tmp[2];
  string str1;
  switch (tp) {
    case 10:                                    /* Convert array of chars */
      str = (kC(item));
      str[sz] = '\0';
      str1 = reinterpret_cast<char*>(str);
      break;
    case -10:                                   /* Convert single char */
      tmp[0] = item->g;
      tmp[1] = '\0';
      str1 = tmp;
      break;
    default:                                    /* Catch invalid input */
      ERROR=1;
      break;
  }
  return str1;
}

/*
 * ===  FUNCTION  ======================================================================
 *         Name:  regexp
 *  Description:  Takes two K strings, converts them to chars and uses boost to
 *                test for regex match. Returns a K int indicating match
 * =====================================================================================
 */
extern "C" K regexp(K input, K rexp)
{
  string in = makeString(input);                /* Convert input to string */
  string ex = makeString(rexp);

  if(ERROR == 1){                               /* Deal with invalid input */
    ERROR = 0;
    return ki(-1);
  }

  boost::regex re(ex);                          /* and away we go... */
  bool out = regex_search(in, re);
  if(out){
    return ki(1);
  }
  else return ki(0);
}