searchengine/oss/loc/analysis/inc/private/statemachine.inl
author hgs
Fri, 15 Oct 2010 12:09:28 +0530
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permissions -rw-r--r--
201041
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/*
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* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
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* All rights reserved.
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* This component and the accompanying materials are made available
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* under the terms of "Eclipse Public License v1.0"
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* which accompanies this distribution, and is available
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* at the URL "http://www.eclipse.org/legal/epl-v10.html".
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*
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* Initial Contributors:
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* Nokia Corporation - initial contribution.
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*
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* Contributors:
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*
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* Description: 
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*
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*/
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#ifndef STATEMACHINE_INL_
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#define STATEMACHINE_INL_
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namespace analysis {
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	template<class Encoding>
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	StateCursor<Encoding>::StateCursor()
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	:  blob_(0), 
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	   pointer_(0)
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	{}
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	template<class Encoding>
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	void StateCursor<Encoding>::reset(byte_t* blob, StateOffset offset)
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	{
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		blob_ = blob; 
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		pointer_ = &blob[offset]; 
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	}
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	template<class Encoding>
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	bool StateCursor<Encoding>::isFinal() 
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	{
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		return Encoding::getFinal(pointer_); 
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	}
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	template<class Encoding>
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	bool StateCursor<Encoding>::next(wchar_t c) 
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	{
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		byte_t* p = pointer_; 
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		// How many transitions we have
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		int n = Encoding::readSuccCount(p);
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		// Search transition that matches 'c'
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		for (int i = 0; i < n; i++) 
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		{ 	// linear speed: O(n/2)
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			wchar_t c2 = Encoding::readChar(p);
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			if ( c2 == c ) {
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				// Found transition, state is changed.
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				// Read pointer to the next state
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				int offset = Encoding::getOffset(p);
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				pointer_ = &blob_[offset];
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				return true; 
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			} else if ( c2 > c ) break;
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			// Skip pointer to next state
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			p += Encoding::SIZEOF_OFFSET;
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		}
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		// Maching transition was not found
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		return false; 
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	}
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	template<class Encoding>
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	const StateOffset StateMachine<Encoding>::ROOT_STATE_OFFSET = 0;
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	template<class Encoding>
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	StateMachine<Encoding>::StateMachine()
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	:	blob_(0)
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	{}
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	template<class Encoding>
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	void StateMachine<Encoding>::reset(byte_t* blob) 
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	{
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		blob_ = blob; 
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	}
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	template<class Encoding>
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	void StateMachine<Encoding>::rootState(StateCursor<Encoding>& cursor)
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	{
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		cursor.reset(blob_, ROOT_STATE_OFFSET); 
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	}
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}
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#endif /* STATEMACHINE_INL_ */