tpie::stack< T > Class Template Reference

An implementation of an external-memory stack. More...

#include <tpie/stack.h>

Public Member Functions
	stack (double blockFactor=1.0)
	Initialize anonymous stack. More...
	stack (const std::string &path, double blockFactor=1.0)
	Initialize named, nontemporary stack. More...
	stack (temp_file &tempFile, double blockFactor=1.0)
	Initialize temporary stack. More...
	~stack ()
	Closes the underlying stream and truncates it to the logical end of the stack. More...
void	push (const T &t)
	Pushes one item onto the stack. More...
const T &	pop ()
	Pops one item from the stack. More...
const T &	top ()
	Peeks at the topmost item on the stack. More...
stream_size_type	size () const
	Returns the number of items currently on the stack. More...
bool	empty () const
	Returns whether the stack is empty or not. More...

Static Public Member Functions
static memory_size_type	memory_usage (float blockFactor=1.0)
	Compute the memory used by a stack. More...

Protected Attributes
file_stream< T >	m_stream
	The stream used to store the items. More...

Detailed Description

template<typename T>
class tpie::stack< T >

An implementation of an external-memory stack.

Definition at line 40 of file stack.h.

Constructor & Destructor Documentation

stack() [1/3]

template<typename T >

tpie::stack< T >::stack ( double  blockFactor = 1.0 )

inline

Initialize anonymous stack.

Definition at line 46 of file stack.h.

        : m_stream(blockFactor)
        , m_buffer(buffer_size(blockFactor))
        , m_bufferItems(0)
    {
        m_stream.open(static_cast<memory_size_type>(0), access_normal,
                      compression_normal);
    }

stack() [2/3]

template<typename T >

tpie::stack< T >::stack ( const std::string &  path, double  blockFactor = 1.0  )

inline

Initialize named, nontemporary stack.

Parameters

path	The path to a file used for storing the items.
blockFactor	The block factor to use

Definition at line 61 of file stack.h.

        : m_stream(blockFactor)
        , m_buffer(buffer_size(blockFactor))
        , m_bufferItems(0)
    {
        m_stream.open(path, access_read_write,
                      static_cast<memory_size_type>(0), access_normal,
                      compression_normal);
        m_stream.seek(0, file_stream_base::end);
    }

stack() [3/3]

template<typename T >

tpie::stack< T >::stack ( temp_file &  tempFile, double  blockFactor = 1.0  )

inline

Initialize temporary stack.

Parameters

tempFile	The temporary file containing the stack
blockFactor	The block factor to use

Definition at line 78 of file stack.h.

        : m_stream(blockFactor)
        , m_buffer(buffer_size(blockFactor))
        , m_bufferItems(0)
    {
        m_stream.open(tempFile, access_read_write,
                      static_cast<memory_size_type>(0), access_normal,
                      compression_normal);
        m_stream.seek(0, file_stream_base::end);
    }

~stack()

template<typename T >

tpie::stack< T >::~stack ( )

inline

Closes the underlying stream and truncates it to the logical end of the stack.

Definition at line 94 of file stack.h.

             {
        empty_buffer();
        m_stream.truncate(m_stream.get_position());
    }

Member Function Documentation

empty()

template<typename T >

bool tpie::stack< T >::empty ( ) const

inline

Returns whether the stack is empty or not.

m_file_stream.can_read_back();

Definition at line 139 of file stack.h.

                              {
        return size()  == 0;
    }

Referenced by tpie::pipelining::bits::reverser_pull_output_t< T >::can_pull(), and tpie::pipelining::bits::reverser_output_t< dest_t >::go().

memory_usage()

template<typename T >

static memory_size_type tpie::stack< T >::memory_usage ( float  blockFactor = 1.0 )

inlinestatic

Compute the memory used by a stack.

Definition at line 146 of file stack.h.

                                                                       {
        return sizeof(stack<T>)
            + file_stream<T>::memory_usage(blockFactor)
            + array<T>::memory_usage(buffer_size(blockFactor));
    }

Referenced by tpie::ami::stack< item_type >::main_memory_usage().

pop()

template<typename T >

const T& tpie::stack< T >::pop ( )

inline

Pops one item from the stack.

Definition at line 113 of file stack.h.

                           {
        if (m_bufferItems) return m_buffer[--m_bufferItems];
        const T & item = m_stream.read_back();
        return item;
    }

Referenced by tpie::pipelining::bits::ami_input_stack_t< dest_t >::go(), tpie::pipelining::bits::reverser_output_t< dest_t >::go(), and tpie::pipelining::bits::reverser_pull_output_t< T >::pull().

push()

template<typename T >

void tpie::stack< T >::push ( const T &  t )

inline

Pushes one item onto the stack.

Returns ERROR_* as given by the underlying stream.

Parameters

t	The item to push onto the stack.

Definition at line 105 of file stack.h.

                                  {
        if (m_buffer.size() == m_bufferItems) empty_buffer();
        m_buffer[m_bufferItems++] = t;
    }

size()

template<typename T >

stream_size_type tpie::stack< T >::size ( ) const

inline

Returns the number of items currently on the stack.

Definition at line 132 of file stack.h.

                                  {
        return m_stream.offset()+m_bufferItems;
    }

Referenced by tpie::stack< item_type >::empty(), tpie::pipelining::bits::ami_input_stack_t< dest_t >::propagate(), and tpie::pipelining::bits::ami_pull_input_stack_t< T >::propagate().

top()

template<typename T >

const T& tpie::stack< T >::top ( )

inline

Peeks at the topmost item on the stack.

Definition at line 122 of file stack.h.

                           {
        if (m_bufferItems) return m_buffer[m_bufferItems-1];
        m_buffer[0] = m_stream.read_back();
        m_stream.read();
        return m_buffer[0];
    }

Member Data Documentation

m_stream

template<typename T >

file_stream<T> tpie::stack< T >::m_stream

protected

The stream used to store the items.

Definition at line 155 of file stack.h.

Referenced by tpie::stack< item_type >::pop(), tpie::stack< item_type >::size(), tpie::stack< item_type >::stack(), tpie::stack< item_type >::top(), and tpie::stack< item_type >::~stack().

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The documentation for this class was generated from the following file:

• stack.h