TokenStreamRewriteEngine.cpp

#include <antlr/config.hpp>
 
#include <string>
#include <list>
#include <vector>
#include <map>
#include <utility>
#include <iostream>
#include <iterator>
#include <sstream>
#include <cassert>
 
#include <antlr/TokenStream.hpp>
#include <antlr/TokenWithIndex.hpp>
#include <antlr/BitSet.hpp>
#include <antlr/TokenStreamRewriteEngine.hpp>
 
#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
namespace antlr {
#endif
 
#ifndef NO_STATIC_CONSTS
const size_t TokenStreamRewriteEngine::MIN_TOKEN_INDEX = 0;
const int TokenStreamRewriteEngine::PROGRAM_INIT_SIZE = 100;
#endif
 
const char* TokenStreamRewriteEngine::DEFAULT_PROGRAM_NAME = "default";
 
namespace {
 
        struct compareOperationIndex {
                typedef TokenStreamRewriteEngine::RewriteOperation RewriteOperation;
                bool operator() ( const RewriteOperation* a, const RewriteOperation* b ) const
                {
                        return a->getIndex() < b->getIndex();
                }
        };
        struct dumpTokenWithIndex {
                dumpTokenWithIndex( ANTLR_USE_NAMESPACE(std)ostream& o ) : out(o) {}
                void operator() ( const RefTokenWithIndex& t ) {
                        out << "[txt='" << t->getText() << "' tp=" << t->getType() << " idx=" << t->getIndex() << "]\n";
                }
                ANTLR_USE_NAMESPACE(std)ostream& out;
        };
}
 
TokenStreamRewriteEngine::TokenStreamRewriteEngine(TokenStream& upstream)
: stream(upstream)
, index(MIN_TOKEN_INDEX)
, tokens()
, programs()
, discardMask()
{
}
 
TokenStreamRewriteEngine::TokenStreamRewriteEngine(TokenStream& upstream, size_t initialSize )
: stream(upstream)
, index(MIN_TOKEN_INDEX)
, tokens(initialSize)
, programs()
, discardMask()
{
}
 
RefToken TokenStreamRewriteEngine::nextToken( void )
{
        RefTokenWithIndex t;
        // suck tokens until end of stream or we find a non-discarded token
        do {
                t = RefTokenWithIndex(stream.nextToken());
                if ( t )
                {
                        t->setIndex(index);  // what is t's index in list?
                        if ( t->getType() != Token::EOF_TYPE ) {
                                tokens.push_back(t);  // track all tokens except EOF
                        }
                        index++;                        // move to next position
                }
        } while ( t && discardMask.member(t->getType()) );
        return RefToken(t);
}
 
void TokenStreamRewriteEngine::rollback( const std::string& programName,
                                                                                                          size_t instructionIndex )
{
        program_map::iterator rewrite = programs.find(programName);
        if( rewrite != programs.end() )
        {
                operation_list& prog = rewrite->second;
                operation_list::iterator
                        j = prog.begin(),
                        end = prog.end();
 
                std::advance(j,instructionIndex);
                if( j != end )
                        prog.erase(j, end);
        }
}
 
void TokenStreamRewriteEngine::originalToStream( std::ostream& out,
                                                                                                                                 size_t start,
                                                                                                                                 size_t end ) const
{
        token_list::const_iterator s = tokens.begin();
        std::advance( s, start );
        token_list::const_iterator e = s;
        std::advance( e, end-start );
        std::for_each( s, e, tokenToStream(out) );
}
 
void TokenStreamRewriteEngine::toStream( std::ostream& out,
                                                                                                          const std::string& programName,
                                                                                                          size_t firstToken,
                                                                                                          size_t lastToken ) const
{
        if( tokens.size() == 0 )
                return;
 
        program_map::const_iterator rewriter = programs.find(programName);
 
        if ( rewriter == programs.end() )
                return;
 
        // get the prog and some iterators in it...
        const operation_list& prog = rewriter->second;
        operation_list::const_iterator
                rewriteOpIndex = prog.begin(),
                rewriteOpEnd = prog.end();
 
        size_t tokenCursor = firstToken;
        // make sure we don't run out of the tokens we have...
        if( lastToken > (tokens.size() - 1) )
          lastToken = tokens.size() - 1;
        
        while ( tokenCursor <= lastToken )
          {
            //                  std::cout << "tokenCursor = " << tokenCursor << " first prog index = " << (*rewriteOpIndex)->getIndex() << std::endl;
            
            if( rewriteOpIndex != rewriteOpEnd )
              {
                size_t up_to_here = std::min(lastToken,(*rewriteOpIndex)->getIndex());
                while( tokenCursor < up_to_here )
                  out << tokens[tokenCursor++]->getText();
              }
            while ( rewriteOpIndex != rewriteOpEnd &&
                    tokenCursor == (*rewriteOpIndex)->getIndex() &&
                    tokenCursor <= lastToken )
              {
                tokenCursor = (*rewriteOpIndex)->execute(out);
                ++rewriteOpIndex;
              }
            if( tokenCursor <= lastToken )
              out << tokens[tokenCursor++]->getText();
          }
        // std::cout << "Handling tail operations # left = " << std::distance(rewriteOpIndex,rewriteOpEnd) << std::endl;
        // now see if there are operations (append) beyond last token index
        std::for_each( rewriteOpIndex, rewriteOpEnd, executeOperation(out) );
        rewriteOpIndex = rewriteOpEnd;
}
 
void TokenStreamRewriteEngine::toDebugStream( std::ostream& out,
                                                                                                                         size_t start,
                                                                                                                         size_t end ) const
{
        token_list::const_iterator s = tokens.begin();
        std::advance( s, start );
        token_list::const_iterator e = s;
        std::advance( e, end-start );
        std::for_each( s, e, dumpTokenWithIndex(out) );
}
 
void TokenStreamRewriteEngine::addToSortedRewriteList( const std::string& programName,
                                                                                                                                                 RewriteOperation* op )
{
        program_map::iterator rewrites = programs.find(programName);
        // check if we got the program already..
        if ( rewrites == programs.end() )
        {
                // no prog make a new one...
                operation_list ops;
                ops.push_back(op);
                programs.insert(std::make_pair(programName,ops));
                return;
        }
        operation_list& prog = rewrites->second;
 
        if( prog.empty() )
        {
                prog.push_back(op);
                return;
        }
 
        operation_list::iterator i, end = prog.end();
        i = end;
        --i;
        // if at or beyond last op's index, just append
        if ( op->getIndex() >= (*i)->getIndex() ) {
                prog.push_back(op); // append to list of operations
                return;
        }
        i = prog.begin();
 
        if( i != end )
        {
                operation_list::iterator pos = std::upper_bound( i, end, op, compareOperationIndex() );
                prog.insert(pos,op);
        }
        else
                prog.push_back(op);
}
 
#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
}
#endif