tpie::file_accessor::stream_accessor< file_accessor_t > Class Template Reference

Inherits tpie::file_accessor::stream_accessor_base< file_accessor_t >.

Public Member Functions
virtual memory_size_type	read_block (void *data, stream_size_type blockNumber, memory_size_type itemCount) override
	Read the given number of items from the given block into the given buffer. More...
virtual void	write_block (const void *data, stream_size_type blockNumber, memory_size_type itemCount) override
	Write the given number of items from the given buffer into the given block. More...
void	open (const std::string &path, bool read, bool write, memory_size_type itemSize, memory_size_type blockSize, memory_size_type maxUserDataSize, cache_hint cacheHint, int compressionFlags)
	Open file for reading and/or writing. More...
void	close ()
memory_size_type	read_user_data (void *data, memory_size_type count)
	Read user data into the given buffer. More...
void	write_user_data (const void *data, memory_size_type count)
	Write user data to the stream. More...
stream_size_type	size () const
	Number of items in stream. More...
const std::string &	path () const
	Path of the file currently open. More...
memory_size_type	user_data_size () const
	Size (in bytes) of the user data. More...
memory_size_type	max_user_data_size () const
	Maximum size (in bytes) of the user data. More...
stream_size_type	byte_size () const
	Size (in bytes) of entire stream as laid out on disk after padding the final block to alignment boundary, including the header and user data. More...
void	truncate (stream_size_type items)
void	set_last_block_read_offset (stream_size_type n)
stream_size_type	get_last_block_read_offset ()
bool	get_compressed ()
int	get_compression_flags ()

Static Public Member Functions
static memory_size_type	memory_usage ()
	Return memory usage of this file accessor. More...

Protected Member Functions
memory_size_type	boundary () const
	Returns the boundary on which we align blocks. More...
memory_size_type	align_to_boundary (memory_size_type z) const
	Given a memory offset, rounds up to the nearest alignment boundary. More...
memory_size_type	header_size () const
	The size of header and user data with padding included. More...
memory_size_type	block_size () const
memory_size_type	block_items () const
memory_size_type	item_size () const
void	set_size (stream_size_type s)

Protected Attributes
file_accessor_t	m_fileAccessor

Detailed Description

template<typename file_accessor_t>
class tpie::file_accessor::stream_accessor< file_accessor_t >

Definition at line 29 of file stream_accessor.h.

Member Function Documentation

template<typename file_accessor_t>

memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::align_to_boundary ( memory_size_type  z ) const

inlineprotectedinherited

Given a memory offset, rounds up to the nearest alignment boundary.

Definition at line 97 of file stream_accessor_base.h.

Referenced by tpie::file_accessor::stream_accessor_base< tpie::file_accessor::posix >::header_size().

{ return (z+boundary()-1)/boundary()*boundary(); }

template<typename file_accessor_t>

memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::boundary ( ) const

inlineprotectedinherited

Returns the boundary on which we align blocks.

Definition at line 91 of file stream_accessor_base.h.

Referenced by tpie::file_accessor::stream_accessor_base< tpie::file_accessor::posix >::align_to_boundary().

{ return 4096; }

template<typename file_accessor_t>

stream_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::byte_size ( ) const

inlineinherited

Size (in bytes) of entire stream as laid out on disk after padding the final block to alignment boundary, including the header and user data.

Definition at line 204 of file stream_accessor_base.h.

Referenced by tpie::file_stream_base::flush_block(), tpie::file_stream_base::truncate(), and tpie::file_base::truncate().

                                              {
        return ((m_size + m_blockItems - 1)/m_blockItems) * m_blockSize + header_size();
    }

template<typename file_accessor_t>

memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::header_size ( ) const

inlineprotectedinherited

The size of header and user data with padding included.

This is the offset at which the first logical block begins.

Definition at line 103 of file stream_accessor_base.h.

Referenced by tpie::file_accessor::stream_accessor_base< tpie::file_accessor::posix >::byte_size(), tpie::file_accessor::stream_accessor< file_accessor_t >::read_block(), and tpie::file_accessor::stream_accessor< file_accessor_t >::write_block().

{ return align_to_boundary(sizeof(stream_header_t)+m_maxUserDataSize); }

template<typename file_accessor_t>

memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::max_user_data_size ( ) const

inlineinherited

Maximum size (in bytes) of the user data.

Definition at line 197 of file stream_accessor_base.h.

Referenced by tpie::file_base_crtp< file_stream_base >::max_user_data_size().

{return m_maxUserDataSize;}

template<typename file_accessor_t>

static memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::memory_usage ( )

inlinestaticinherited

Return memory usage of this file accessor.

Definition at line 177 of file stream_accessor_base.h.

Referenced by tpie::file< T >::memory_usage(), and tpie::uncompressed_stream< T >::memory_usage().

{return sizeof(stream_accessor_base);}

template<typename file_accessor_t>

void tpie::file_accessor::stream_accessor_base< file_accessor_t >::open ( const std::string &  path, bool  read, bool  write, memory_size_type  itemSize, memory_size_type  blockSize, memory_size_type  maxUserDataSize, cache_hint  cacheHint, int  compressionFlags  )

inlineinherited

Open file for reading and/or writing.

template<typename file_accessor_t>

const std::string& tpie::file_accessor::stream_accessor_base< file_accessor_t >::path ( ) const

inlineinherited

Path of the file currently open.

Definition at line 187 of file stream_accessor_base.h.

Referenced by tpie::file_base_crtp< file_stream_base >::path().

{return m_path;}

template<typename file_accessor_t >

virtual memory_size_type tpie::file_accessor::stream_accessor< file_accessor_t >::read_block ( void *  data, stream_size_type  blockNumber, memory_size_type  itemCount  )

inlineoverridevirtual

Read the given number of items from the given block into the given buffer.

Parameters

data	Buffer in which to store data. Must be able to hold at least sizeof(T)*itemCount bytes.
blockNumber	Number of block in which to begin reading.
itemCount	Number of items to read from beginning of given block. Must be less than m_blockItems.

Implements tpie::file_accessor::stream_accessor_base< file_accessor_t >.

Definition at line 31 of file stream_accessor.h.

References tpie::file_accessor::stream_accessor_base< file_accessor_t >::header_size(), and tpie::file_accessor::stream_accessor_base< file_accessor_t >::size().

    {
        stream_size_type loc = this->header_size() + blockNumber*this->block_size();
        this->m_fileAccessor.seek_i(loc);
        stream_size_type offset = blockNumber*this->block_items();
        if (offset + itemCount > this->size()) itemCount = static_cast<memory_size_type>(this->size() - offset);
        memory_size_type z=itemCount*this->item_size();
        this->m_fileAccessor.read_i(data, z);
        return itemCount;
    }

template<typename file_accessor_t>

memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::read_user_data ( void *  data, memory_size_type  count  )

inlineinherited

Read user data into the given buffer.

Parameters

data	Buffer in which to store user data.
count	Size of buffer, in bytes. The method will read at most this number of bytes.

Returns

Number of bytes of user data actually read, in case this is less than count.

Referenced by tpie::file_base_crtp< file_stream_base >::read_user_data().

template<typename file_accessor_t>

stream_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::size ( ) const

inlineinherited

Number of items in stream.

Definition at line 182 of file stream_accessor_base.h.

Referenced by tpie::file_accessor::stream_accessor< file_accessor_t >::read_block(), and tpie::file_accessor::stream_accessor< file_accessor_t >::write_block().

{return m_size;}

template<typename file_accessor_t>

memory_size_type tpie::file_accessor::stream_accessor_base< file_accessor_t >::user_data_size ( ) const

inlineinherited

Size (in bytes) of the user data.

Definition at line 192 of file stream_accessor_base.h.

Referenced by tpie::file_base_crtp< file_stream_base >::user_data_size().

{return m_userDataSize;}

template<typename file_accessor_t >

virtual void tpie::file_accessor::stream_accessor< file_accessor_t >::write_block ( const void *  data, stream_size_type  blockNumber, memory_size_type  itemCount  )

inlineoverridevirtual

Write the given number of items from the given buffer into the given block.

Parameters

data	Buffer from which to write data. Must hold at least sizeof(T)*itemCount bytes of data.
blockNumber	Number of block in which to write.
itemCount	Number of items to write to beginning of given block. Must be less than m_blockItems.

Implements tpie::file_accessor::stream_accessor_base< file_accessor_t >.

Definition at line 44 of file stream_accessor.h.

References tpie::file_accessor::stream_accessor_base< file_accessor_t >::header_size(), and tpie::file_accessor::stream_accessor_base< file_accessor_t >::size().

    {
        stream_size_type loc = this->header_size() + blockNumber*this->block_size();
        // Here, we may seek beyond the file size.
        // However, lseek(2) specifies that the file will be padded with zeroes in this case,
        // and on Windows, the file is padded with arbitrary garbage (which is ok).
        this->m_fileAccessor.seek_i(loc);
        stream_size_type offset = blockNumber*this->block_items();
        memory_size_type z=itemCount*this->item_size();
        this->m_fileAccessor.write_i(data, z);
        if (offset+itemCount > this->size()) this->set_size(offset+itemCount);
    }

template<typename file_accessor_t>

void tpie::file_accessor::stream_accessor_base< file_accessor_t >::write_user_data ( const void *  data, memory_size_type  count  )

inlineinherited

Write user data to the stream.

Parameters

data	Buffer from which to write user data.
count	Number of bytes to write. Cannot exceed max_user_data_size().

Referenced by tpie::file_base_crtp< file_stream_base >::write_user_data().

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

• file_accessor/stream_accessor.h