mpBuffer< _Type, _Alloc > Class Template Reference

template<typename _Type, typename _Alloc = std::allocator<_Type>>
class mpBuffer< _Type, _Alloc >

A generic buffer which may be either used as a simple vector or ring buffer.

The implementation of this class is based on the STL vector and behaves exactly like it in case it is used as an array. Only the methods referenced by the muParser have been implemented - some missing parts like iterators are not available but can still be implemented.

Public Types
typedef _Type &	reference
	Reference type of the data being stored in the vector.
typedef const _Type &	const_reference
	Constant reference type of the data being stored in the vector.
typedef _Type *	pointer
	Pointer type of the data being stored in the vector.
typedef const _Type *	const_pointer
	Constant pointer type of the data being stored in the vector.
typedef int	size_type
	The standard size type is int to allow negative indices for access.
typedef _Type	value_type
	Data type of the data being stored.
typedef _Alloc	allocator_type
	Allocator type for the used data type.

Public Member Functions
	mpBuffer (const allocator_type &a=allocator_type())
	Creates a new buffer object with no elements.
	mpBuffer (size_type n, bool rb=false, const value_type &v=value_type(), const allocator_type &a=allocator_type())
	Creates a new buffer object with the specified number of elements and the specified type.
	mpBuffer (const mpBuffer< value_type, allocator_type > &buf)
	Creates a new buffer by copying all elements of the specified buffer object.
virtual mpBuffer &	operator= (const mpBuffer< value_type, allocator_type > &buf)
	Assignment operator - deallocates all currently saved object in the buffer and creates a copy of the specified buffer.
virtual	~mpBuffer ()
	The destructor of the mpBuffer class.
virtual size_type	size () const
	Returns the current size of the buffer.
virtual size_type	max_size () const
	Returns the maximum number of elements which can be saved in a the buffer class.
virtual void	resize (size_type sz, value_type c=value_type())
	Resizes the current buffer to the given size.
virtual size_type	capacity () const
	Returns the capacity of the current buffer which is equal to the size.
virtual bool	empty () const
	Returns true if the current amount of saved elements is zero.
virtual reference	at (size_type n)
	Returns the element currently saved at the specified position.
virtual const_reference	at (size_type n) const
	Returns the element currently saved at the specified position.
virtual reference	operator[] (size_type n)
	Returns the element currently saved at the specified position, but uses a modulo operation in case of a ring buffer.
virtual const_reference	operator[] (size_type n) const
	Returns the element currently saved at the specified position, but uses a modulo operation in case of a ring buffer.
virtual reference	front ()
	Returns the first element of the current buffer.
virtual const_reference	front () const
	Returns the first element of the current buffer.
virtual reference	back ()
	Returns the last element of the current buffer.
virtual const_reference	back () const
	Returns the last element of the current buffer.
virtual allocator_type	get_allocator () const
	Returns the allocator type of the current buffer.
virtual void	setCurrentIdx (size_type n)
	Sets the current index of the ring buffer to the given value and adapts internal pointers to the first and last element of the ring buffer.
virtual size_type	getFirst () const
	Returns the first element saved in the current buffer.
virtual size_type	getLast () const
	Returns the last element saved in the current buffer.
virtual size_type	getUsedBufferSize () const
	Returns the number of accessed elements of the ring buffer which is equivalent to the actually used buffer size.
virtual bool	isRingBuffer () const
	Returns true if the current buffer behaves like a a ring buffer, false otherwise.
virtual void	setRingBuffer ()
	Sets the current buffer to behave like a ring buffer.
virtual void	setVector ()
	Sets the current buffer to behave like a vector.

Protected Member Functions
virtual void	clean ()
	Releases all elements by calling the destructor of the saved elements and deallocating all needed memory.

Protected Attributes
size_type	_size
	Current number of elements in use.
allocator_type	_allocator
	Allocator of current element type.
pointer	_fields
	Pointer to all elements of buffer.
bool	_is_ringbuffer
	Attribute deciding whether the current buffer implements a ringbuffer.
size_type	_first
	In case of a ring buffer, this is the index to the first valid element.
size_type	_last
	In case of a ring buffer, this is the index to the last valid element.
size_type	_used_elements
	Saves the number of currently used elements for a ring buffer.

Member Typedef Documentation

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef _Alloc mpBuffer< _Type, _Alloc >::allocator_type

Allocator type for the used data type.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef const _Type* mpBuffer< _Type, _Alloc >::const_pointer

Constant pointer type of the data being stored in the vector.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef const _Type& mpBuffer< _Type, _Alloc >::const_reference

Constant reference type of the data being stored in the vector.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef _Type* mpBuffer< _Type, _Alloc >::pointer

Pointer type of the data being stored in the vector.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef _Type& mpBuffer< _Type, _Alloc >::reference

Reference type of the data being stored in the vector.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef int mpBuffer< _Type, _Alloc >::size_type

The standard size type is int to allow negative indices for access.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

typedef _Type mpBuffer< _Type, _Alloc >::value_type

Data type of the data being stored.

Constructor & Destructor Documentation

template<typename _Type , typename _Alloc = std::allocator<_Type>>

mpBuffer< _Type, _Alloc >::mpBuffer ( const allocator_type &  a = allocator_type() )

inlineexplicit

Creates a new buffer object with no elements.

The default buffer type is array.

Parameters

[in]

a

Defines the allocator type for the class which shall be saved in the buffer. Defaults to the standard allocator.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

mpBuffer< _Type, _Alloc >::mpBuffer ( size_type  n, bool  rb = false, const value_type &  v = value_type(), const allocator_type &  a = allocator_type()  )

inlineexplicit

Creates a new buffer object with the specified number of elements and the specified type.

Parameters

[in]	n	Initial size of the array.
[in]	rb	Defines the type of the array: If set to true, the buffer is a ring buffer, otherwise, it will be an array.
[in]	v	Defines the class type which shall be saved in the buffer.
[in]	a	Defines the allocator type for the class which shall be saved in the buffer. Defaults to the standard allocator.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

mpBuffer< _Type, _Alloc >::mpBuffer ( const mpBuffer< value_type, allocator_type > &  buf )

inline

Creates a new buffer by copying all elements of the specified buffer object.

Parameters

[in]

buf

The buffer to copy.

Warning

Take care when copying a buffer containing pointers to elements - only the pointers will be copied, but not the elements themselves.

Member Function Documentation

template<typename _Type , typename _Alloc = std::allocator<_Type>>

virtual reference mpBuffer< _Type, _Alloc >::at ( size_type  n )

inlinevirtual

Returns the element currently saved at the specified position.

This function behaves the same for the array and ring buffer implementation and does not change the _used_elements field.

Parameters

[in]

n

The position of the element saved in the buffer.

Exceptions

std::out_of_range

If the specified position is not within 0 <= n < size.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

virtual const_reference mpBuffer< _Type, _Alloc >::at ( size_type  n ) const

inlinevirtual

Returns the element currently saved at the specified position.

This function behaves the same for the array and ring buffer implementation and does not change the _used_elements field.

Parameters

[in]

n

The index of the element saved in the buffer.

Exceptions

std::out_of_range

If the specified position is not within 0 <= n < size.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

virtual mpBuffer& mpBuffer< _Type, _Alloc >::operator= ( const mpBuffer< value_type, allocator_type > &  buf )

inlinevirtual

Assignment operator - deallocates all currently saved object in the buffer and creates a copy of the specified buffer.

Parameters

[in]

buf

The buffer to copy.

Warning

Take care when copying a buffer containing pointers to elements - only the pointers will be copied, but not the elements themselves.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

virtual reference mpBuffer< _Type, _Alloc >::operator[] ( size_type  n )

inlinevirtual

Returns the element currently saved at the specified position, but uses a modulo operation in case of a ring buffer.

Parameters

[in]

n

The index of the element saved in the buffer.

Exceptions

std::out_of_range

If the current buffer is an array and the index is not within 0 <= n < size or the number of used elements in the ring buffer is greater than the current size.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

virtual const_reference mpBuffer< _Type, _Alloc >::operator[] ( size_type  n ) const

inlinevirtual

Returns the element currently saved at the specified position, but uses a modulo operation in case of a ring buffer.

Parameters

[in]

n

The index of the element saved in the buffer.

Exceptions

std::out_of_range

If the current buffer is an array and the index is not within 0 <= n < size or the number of used elements in the ring buffer is greater than the current size.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

virtual void mpBuffer< _Type, _Alloc >::resize ( size_type  sz, value_type  c = value_type()  )

inlinevirtual

Resizes the current buffer to the given size.

Parameters

[in]	sz	The size of the new buffer.
[in]	c	The class type of the elements to save in the buffer.

Exceptions

std::length_error

If the new size of a ring buffer will be less than the current number of elements in use.

Member Data Documentation

template<typename _Type , typename _Alloc = std::allocator<_Type>>

allocator_type mpBuffer< _Type, _Alloc >::_allocator

protected

Allocator of current element type.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

pointer mpBuffer< _Type, _Alloc >::_fields

protected

Pointer to all elements of buffer.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

size_type mpBuffer< _Type, _Alloc >::_first

protected

In case of a ring buffer, this is the index to the first valid element.

Initial value is -1.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

bool mpBuffer< _Type, _Alloc >::_is_ringbuffer

protected

Attribute deciding whether the current buffer implements a ringbuffer.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

size_type mpBuffer< _Type, _Alloc >::_last

mutableprotected

In case of a ring buffer, this is the index to the last valid element.

Initial value is -1.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

size_type mpBuffer< _Type, _Alloc >::_size

protected

Current number of elements in use.

template<typename _Type , typename _Alloc = std::allocator<_Type>>

size_type mpBuffer< _Type, _Alloc >::_used_elements

mutableprotected

Saves the number of currently used elements for a ring buffer.