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tim |
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/* ANTLR Translator Generator |
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* Project led by Terence Parr at http://www.jGuru.com |
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* Software rights: http://www.antlr.org/license.html |
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* |
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* $Id: InputBuffer.cpp,v 1.1 2005-12-02 15:38:02 tim Exp $ |
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*/ |
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#include "antlr/config.hpp" |
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#include "antlr/InputBuffer.hpp" |
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#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE |
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namespace antlr { |
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#endif |
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/** Ensure that the character buffer is sufficiently full */ |
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void InputBuffer::fill(unsigned int amount) |
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{ |
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syncConsume(); |
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// Fill the buffer sufficiently to hold needed characters |
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while (queue.entries() < amount + markerOffset) |
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{ |
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// Append the next character |
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queue.append(getChar()); |
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} |
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} |
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/** get the current lookahead characters as a string |
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* @warning it may treat 0 and EOF values wrong |
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*/ |
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ANTLR_USE_NAMESPACE(std)string InputBuffer::getLAChars( void ) const |
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{ |
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ANTLR_USE_NAMESPACE(std)string ret; |
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for(unsigned int i = markerOffset; i < queue.entries(); i++) |
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ret += queue.elementAt(i); |
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return ret; |
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} |
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/** get the current marked characters as a string |
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* @warning it may treat 0 and EOF values wrong |
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*/ |
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ANTLR_USE_NAMESPACE(std)string InputBuffer::getMarkedChars( void ) const |
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{ |
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ANTLR_USE_NAMESPACE(std)string ret; |
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for(unsigned int i = 0; i < markerOffset; i++) |
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ret += queue.elementAt(i); |
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return ret; |
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} |
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/** Return an integer marker that can be used to rewind the buffer to |
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* its current state. |
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*/ |
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unsigned int InputBuffer::mark() |
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{ |
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syncConsume(); |
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nMarkers++; |
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return markerOffset; |
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} |
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/** Rewind the character buffer to a marker. |
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* @param mark Marker returned previously from mark() |
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*/ |
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void InputBuffer::rewind(unsigned int mark) |
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{ |
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syncConsume(); |
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markerOffset = mark; |
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nMarkers--; |
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} |
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unsigned int InputBuffer::entries() const |
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{ |
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//assert(queue.entries() >= markerOffset); |
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return queue.entries() - markerOffset; |
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} |
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#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE |
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} |
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#endif |
