elexd.cpp

用于词法分析的词法分析器

/* $Id: elexd.cpp,v 1.5 1997/04/26 09:38:58 matt Exp $

   Elex debugger application.

   (c) Matt Phillips 1996. */

#include <iostream.h>
#include <fstream.h>
#include <errno.h>

#include <foo/FooParser.h>
#include <foo/FooObject.h>
#include <cppscan/XInputStream.h>

#include "DynamicScanner.h"

void error (const string message, int abortcode = 0)
{
  cerr << "elexd: " << message << endl;
  if (abortcode > 0) exit (abortcode);
}

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

int main (int argc, char **argv)
{
  if (argc != 2)
  {
    cerr << "usage: elexd <scanner_definition>\n";
    return 1;
  }

  ifstream foofile (argv [1]);
  checkStream (foofile, argv [1]);
  BufferedInputStream fooinput (foofile);
  FooParser parser (fooinput);
  foofile.close ();

  if (parser.nErrors () == 0)
  {
    XInputStream input (cin, "stdin");
    DynamicScanner scanner (parser.getObject (), input);
    
    scanner.getNext ();

    while (!scanner.eof ())
    {
      cout << scanner.getTextLine () << ':' <<
	      scanner.getTextColumn () << ": " <<
	      scanner.getProduction () << ": \"" <<
	      scanner.getText () << "\"\n";
      scanner.getNext ();
    }
  } else
  {
    error ("errors in scanner specification:");
    cerr << parser.getErrors () << endl;
    return 1;
  }

  return 0;
}