elexc.cpp

用于词法分析的词法分析器

/*
  $Id: elexc.cpp,v 1.8 1997/05/17 05:14:31 matt Exp $

  Elex compiler application
  
  (c) Jan 96 Matt Phillips.
  */

#include <unistd.h>
#include <std/string.h>
#include <fstream.h>

#include <compiler/BufferedInputStream.h>

#include "ElexCompiler.h"

//////////////////// utility functions

void errorMessage (const string message)
{
  cerr << "elexc: " << message << endl;
}

// check stream <str> which should be a stream opened for file with
// <name> is open.
int checkStream (ios &str, const string name)
{
  if (!str)
  {
    errorMessage ("could not open '" + name + "': " + strerror (errno));
    return 0;
  } else
    return 1;
}

//////////////////// Main

int main (int argc, char **argv)
{
  if (argc != 3)
  {
    cerr << "usage: elexc <scanner.elx> <codefrags.ecf>\n";
    return 1;
  }

  char *scannerFile = argv [1];
  char *codeFragsFile = argv [2];

  ifstream scannerStream (scannerFile);
  ofstream codeFragStream (codeFragsFile);

  if (checkStream (scannerStream, scannerFile) &&
      checkStream (codeFragStream, codeFragsFile))
  {
    string filename (scannerFile);
    BufferedInputStream inputStream (scannerStream, filename);
    ElexCompiler elexComp (inputStream, codeFragStream);

    // output any messages
    if (elexComp.nErrors () > 0 || elexComp.nWarnings () > 0)
    {
      cerr << elexComp.getErrors ();
    }

    if (elexComp.nErrors () == 0)
      elexComp.getScannerDef ().outputScanner (cout);
    else
      return 1;
  } else
    return 1;

  return 0;
}