InputBuffer.cpp

/* ANTLR Translator Generator
 * Project led by Terence Parr at http://www.jGuru.com
 * Software rights: http://www.antlr.org/license.html
 *
 * $Id$
 */
 
#include "antlr/config.hpp"
#include "antlr/InputBuffer.hpp"
#include  <iostream>
#ifdef IS_MPI
#include "mpi.h"
#endif
 
 
#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
namespace antlr {
#endif
 
/** Ensure that the character buffer is sufficiently full */
void InputBuffer::fill(unsigned int amount)
{
        syncConsume();
 
        // Fill the buffer sufficiently to hold needed characters
        while (queue.entries() < amount + markerOffset)
        {         
            // Append the next character
            queue.append(getChar());            
        }
}
 
/** get the current lookahead characters as a string
 * @warning it may treat 0 and EOF values wrong
 */
ANTLR_USE_NAMESPACE(std)string InputBuffer::getLAChars( void ) const
{
        ANTLR_USE_NAMESPACE(std)string ret;
 
        for(unsigned int i = markerOffset; i < queue.entries(); i++)
                ret += queue.elementAt(i);
 
        return ret;
}
 
/** get the current marked characters as a string
 * @warning it may treat 0 and EOF values wrong
 */
ANTLR_USE_NAMESPACE(std)string InputBuffer::getMarkedChars( void ) const
{
        ANTLR_USE_NAMESPACE(std)string ret;
 
        for(unsigned int i = 0; i < markerOffset; i++)
                ret += queue.elementAt(i);
 
        return ret;
}
 
/** Return an integer marker that can be used to rewind the buffer to
 * its current state.
 */
unsigned int InputBuffer::mark()
{
        syncConsume();
        nMarkers++;
        return markerOffset;
}
 
/** Rewind the character buffer to a marker.
 * @param mark Marker returned previously from mark()
 */
void InputBuffer::rewind(unsigned int mark)
{
        syncConsume();
        markerOffset = mark;
        nMarkers--;
}
 
unsigned int InputBuffer::entries() const
{
        //assert(queue.entries() >= markerOffset);
        return queue.entries() - markerOffset;
}
 
#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
}
#endif