src/xalanc/Include/STLHelper.hpp

/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#if !defined(STLHELPERS_HEADER_GUARD_1357924680)
#define STLHELPERS_HEADER_GUARD_1357924680



// Base include file.  Must be first.
#include <xalanc/Include/PlatformDefinitions.hpp>



#include <algorithm>
#include <functional>



#include <xalanc/Include/XalanMap.hpp>



XALAN_CPP_NAMESPACE_BEGIN



/**
 * Functor to delete objects, used in STL iteration algorithms.
 */
template <class T>
#if defined(XALAN_NO_STD_NAMESPACE)
struct DeleteFunctor : public unary_function<const T*, void>
#else
struct DeleteFunctor : public std::unary_function<const T*, void>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef unary_function<const T*, void>	BaseClassType;
#else
	typedef std::unary_function<const T*, void>	BaseClassType;
#endif

	typedef typename BaseClassType::result_type		result_type;
	typedef typename BaseClassType::argument_type	argument_type;

	/**
	 * Delete the object pointed to by argument.
	 *
	 * @param thePointer pointer to object to be deleted
	 */
	result_type
	operator()(argument_type	thePointer) const
	{
#if defined(XALAN_CANNOT_DELETE_CONST)
		delete (T*)thePointer;
#else
		delete thePointer;
#endif
	}
};



#if !defined(XALAN_SGI_BASED_STL)

/**
 * Functor to retrieve the key of a key-value pair in a map, used in STL
 * iteration algorithms.
 */
template <class PairType>
#if defined(XALAN_NO_STD_NAMESPACE)
struct select1st : public unary_function<PairType, PairType::first_type>
#else
struct select1st : public std::unary_function<PairType, typename PairType::first_type>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef unary_function<PairType, PairType::first_type>	BaseClassType;
#else
	typedef std::unary_function<PairType, typename PairType::first_type>	BaseClassType;
#endif

	typedef typename BaseClassType::result_type		result_type;
	typedef typename BaseClassType::argument_type	argument_type;

	typedef PairType								value_type;

	/**
	 * Retrieve the key of a key-value pair.
	 *
	 * @param thePair key-value pair
	 * @return key
	 */
	result_type
	operator()(const argument_type&		thePair) const
	{
		return thePair.first;
	}
};



/**
 * Functor to retrieve the value of a key-value pair in a map, used in STL
 * iteration algorithms.
 */
template <class PairType>
#if defined(XALAN_NO_STD_NAMESPACE)
struct select2nd : public unary_function<PairType, PairType::second_type>
#else
struct select2nd : public std::unary_function<PairType, typename PairType::second_type>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef unary_function<PairType, PairType::second_type>	BaseClassType;
#else
	typedef std::unary_function<PairType, typename PairType::second_type>	BaseClassType;
#endif

	typedef typename BaseClassType::result_type		result_type;
	typedef typename BaseClassType::argument_type	argument_type;

	typedef PairType								value_type;

	/**
	 * Retrieve the value of a key-value pair.
	 *
	 * @param thePair key-value pair
	 * @return value
	 */
	result_type
	operator()(const argument_type&		thePair) const
	{
		return thePair.second;
	}
};

#endif



/**
 * Functor to call a clear() member function on its argument.
 */
template <class Type>
#if defined(XALAN_NO_STD_NAMESPACE)
struct ClearFunctor : public unary_function<Type, void>
#else
struct ClearFunctor : public std::unary_function<Type, void>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef unary_function<Type, void>		BaseClassType;
#else
	typedef std::unary_function<Type, void>	BaseClassType;
#endif

	typedef typename BaseClassType::result_type		result_type;
	typedef typename BaseClassType::argument_type	argument_type;

	typedef Type									value_type;

	/**
	 * Retrieve the value of a key-value pair.
	 *
	 * @param thePair key-value pair
	 * @return value
	 */
	result_type
	operator()(argument_type&	theArg) const
	{
		theArg.clear();
	}
};



/**
 * Functor to delete value objects in maps, used in STL iteration algorithms.
 */
template <class T>
#if defined(XALAN_NO_STD_NAMESPACE)
struct MapValueDeleteFunctor : public unary_function<const typename T::value_type&, void>
#else
struct MapValueDeleteFunctor : public std::unary_function<const typename T::value_type&, void>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef unary_function<const typename T::value_type&, void>		BaseClassType;
#else
	typedef std::unary_function<const typename T::value_type&, void>	BaseClassType;
#endif

	typedef typename BaseClassType::result_type		result_type;
	typedef typename BaseClassType::argument_type	argument_type;

	/**
	 * Delete the value object in a map value pair.  The value of the pair must
	 * be of pointer type.
	 *
	 * @param thePair key-value pair
	 */
	result_type
	operator()(argument_type	thePair) const
	{
		delete thePair.second;
	}
};



template<class T>
MapValueDeleteFunctor<T>
makeMapValueDeleteFunctor(const T&	/* theMap */)
{
	return MapValueDeleteFunctor<T>();
}



/**
 * This functor is designed to compare 0-terminated arrays.  It substitutes
 * for the default less<type*> so that pointers to arrays can be compared,
 * rather than copies of arrays.  For example, you might want to use C-style
 * strings as keys in a map, rather than string objects.  The default
 * algorithm less<const char*> would just compare the pointers, and not the
 * vector of characters to which it points.  Using this algorithm instead of
 * the default will allow the map to work as expected.
 */
template<class T>
#if defined(XALAN_NO_STD_NAMESPACE)
struct less_null_terminated_arrays : public binary_function<const T*, const T*, bool>
#else
struct less_null_terminated_arrays : public std::binary_function<const T*, const T*, bool>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef binary_function<const T*, const T*, bool>			BaseClassType;
#else
	typedef std::binary_function<const T*, const T*, bool>		BaseClassType;
#endif

	typedef typename BaseClassType::result_type				result_type;
	typedef typename BaseClassType::first_argument_type		first_argument_type;
	typedef typename BaseClassType::second_argument_type	second_argument_type;

	/**
	 * Compare the values of two objects.
	 *
	 *
	 * @param theLHS first object to compare
	 * @param theRHS second object to compare
	 * @return true if objects are the same
	 */
	result_type
	operator()(
			first_argument_type		theLHS,
			second_argument_type	theRHS) const
	{
		while(*theLHS && *theRHS)
		{
			if (*theLHS != *theRHS)
			{
				break;
			}
			else
			{
				theLHS++;
				theRHS++;
			}
		}

		return *theLHS < *theRHS ? true : false;
	}
};



template<class T>
struct equal_null_terminated_arrays : public XALAN_STD_QUALIFIER binary_function<const T*, const T*, bool>
{
	typedef XALAN_STD_QUALIFIER binary_function<const T*, const T*, bool>		BaseClassType;

	typedef typename BaseClassType::result_type				result_type;
	typedef typename BaseClassType::first_argument_type		first_argument_type;
	typedef typename BaseClassType::second_argument_type	second_argument_type;
	/**
	 * Compare the values of two objects.
	 *
	 *
	 * @param theLHS first object to compare
	 * @param theRHS second object to compare
	 * @return true if objects are the same
	 */
	result_type
	operator()(
			first_argument_type		theLHS,
			second_argument_type	theRHS) const
	{
		while(*theLHS && *theRHS)
		{
			if (*theLHS != *theRHS)
			{
				return false;
			}
			else
			{
				++theLHS;
				++theRHS;
			}
		}

		if (*theLHS || *theRHS)
		{
			return false;
		}
		else
		{
			return true;
		}
	}
};

template <class T>
struct hash_null_terminated_arrays : public XALAN_STD_QUALIFIER unary_function<const T*, size_t>
{
	typedef XALAN_STD_QUALIFIER unary_function<const T*, size_t>		BaseClassType;

	typedef typename BaseClassType::result_type				result_type;
	typedef typename BaseClassType::argument_type		argument_type;

	result_type
	operator() (argument_type	theKey) const
	{
		const T*		theRawBuffer = theKey;

		result_type		theHashValue = 0; 

		while (*theRawBuffer)
		{
			theHashValue = 5 * theHashValue + *theRawBuffer;
			++theRawBuffer;
		}

		return ++theHashValue;
	}
};



template<>
struct XalanMapKeyTraits<const XalanDOMChar*>
{
	typedef hash_null_terminated_arrays<XalanDOMChar>	Hasher;
	typedef equal_null_terminated_arrays<XalanDOMChar>	Comparator;
};



template<class CollectionType>
class CollectionClearGuard
{
public:

	CollectionClearGuard(CollectionType&	theCollection) :
		m_collection(&theCollection)
	{
	}

	~CollectionClearGuard()
	{
		if (m_collection != 0)
		{
			m_collection->clear();
		}
	}

	void
	release()
	{
		m_collection = 0;
	}

private:

	// Not implemented...
	CollectionClearGuard(const CollectionClearGuard<CollectionType>&);

	CollectionClearGuard<CollectionType>&
	operator=(const CollectionClearGuard<CollectionType>&);

	// Data members...
	CollectionType*		m_collection;
};



template<class CollectionType, class DeleteFunctorType>
class CollectionDeleteGuard
{
public:

	CollectionDeleteGuard(CollectionType&	theCollection) :
		m_collection(&theCollection)
	{
	}

	~CollectionDeleteGuard()
	{
		if (m_collection != 0)
		{
#if !defined(XALAN_NO_STD_NAMESPACE)
			using std::for_each;
#endif

			// Delete all of the objects in the temp vector.
			for_each(m_collection->begin(),
					 m_collection->end(),
					 DeleteFunctorType());
		}
	}

	void
	release()
	{
		m_collection = 0;
	}

private:

	// Not implemented...
	CollectionDeleteGuard(const CollectionDeleteGuard<CollectionType, DeleteFunctorType>&);

	CollectionDeleteGuard<CollectionType, DeleteFunctorType>&
	operator=(const CollectionDeleteGuard<CollectionType, DeleteFunctorType>&);

	// Data members...
	CollectionType*		m_collection;
};



template<class T>
#if defined(XALAN_NO_STD_NAMESPACE)
struct pointer_equals : public binary_function<const T*, const T*, bool>
#else
struct pointer_equals : public std::binary_function<const T*, const T*, bool>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef binary_function<const T*, const T*, bool>			BaseClassType;
#else
	typedef std::binary_function<const T*, const T*, bool>		BaseClassType;
#endif

	typedef typename BaseClassType::result_type				result_type;
	typedef typename BaseClassType::first_argument_type		first_argument_type;
	typedef typename BaseClassType::second_argument_type	second_argument_type;

	result_type
	operator()(
		first_argument_type		theLHS,
		second_argument_type	theRHS) const
	{
		assert(theLHS != 0 && theRHS != 0);

		return *theLHS == *theRHS;
	}
};



template<class T>
#if defined(XALAN_NO_STD_NAMESPACE)
struct pointer_equals_predicate : public unary_function<const T*, bool>
#else
struct pointer_equals_predicate : public std::unary_function<const T*, bool>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef unary_function<const T*, bool>			BaseClassType;
#else
	typedef std::unary_function<const T*, bool>		BaseClassType;
#endif

	typedef typename BaseClassType::result_type		result_type;
	typedef typename BaseClassType::argument_type	argument_type;

	pointer_equals_predicate(argument_type	theArg) :
		m_arg(theArg)
	{
	}

	result_type
	operator()(
		argument_type	theOther) const
	{
		assert(theOther != 0);

		return *theOther == *m_arg;
	}

private:

	const argument_type		m_arg;
};



template<class T>
#if defined(XALAN_NO_STD_NAMESPACE)
struct pointer_less : public binary_function<const T*, const T*, bool>
#else
struct pointer_less : public std::binary_function<const T*, const T*, bool>
#endif
{
#if defined(XALAN_NO_STD_NAMESPACE)
	typedef binary_function<const T*, const T*, bool>			BaseClassType;
#else
	typedef std::binary_function<const T*, const T*, bool>		BaseClassType;
#endif

	typedef typename BaseClassType::result_type				result_type;
	typedef typename BaseClassType::first_argument_type		first_argument_type;
	typedef typename BaseClassType::second_argument_type	second_argument_type;

	result_type
	operator()(
		first_argument_type		theLHS,
		second_argument_type	theRHS) const
	{
		assert(theLHS != 0 && theRHS != 0);

#if !defined(XALAN_NO_STD_NAMESPACE)
		using std::less;
#endif

		return less<T>()(*theLHS, *theRHS);
	}
};


template<class T>
struct pointer_equal : public XALAN_STD_QUALIFIER binary_function<const T*, const T*, bool>
{
	typedef XALAN_STD_QUALIFIER binary_function<const T*, const T*, bool> BaseClassType;

	typedef typename BaseClassType::result_type				result_type;
	typedef typename BaseClassType::first_argument_type		first_argument_type;
	typedef typename BaseClassType::second_argument_type	second_argument_type;

	result_type
	operator()(
		first_argument_type		theLHS,
		second_argument_type	theRHS) const
	{
		assert(theLHS != 0 && theRHS != 0);
		return XALAN_STD_QUALIFIER equal_to<T>()(*theLHS, *theRHS);
	}
};




XALAN_CPP_NAMESPACE_END



#endif	// STLHELPERS_HEADER_GUARD_1357924680