block Class Reference

data block, used to hold the data that are being copied (or checksummed). More...

#include <block.h>

Public Member Functions
	block (size_t aBlockSize)
	Allocate block via mmap to ensure proper alignment along page borders, needed for efficient read/write ops. More...
	~block ()
size_t	size () const
bool	empty () const
size_t	max_size () const
size_t	offset () const
void	clear (size_t aOffset)
void	bump_size (size_t additionalBytes)
bool	isHole () const
void	setHoleState (bool holeState)
void *	bufferAt (size_t offset)
	only way to access the data in the block More...
const void *	bufferAt (size_t offset) const
	only way to access the data in the block More...

Static Public Member Functions
static const void *	nullBuffer ()
static size_t	nullBufferSize ()

Private Attributes
void *	buffer
size_t	bytes
	number of bytes actually stored here More...
size_t	blockSize
	capacity of the block More...
size_t	startOffset
	offset in the file that is represented by this block More...
bool	hole
	represents a hole in the file with bytes bytes. More...

Detailed Description

data block, used to hold the data that are being copied (or checksummed).

The interface implements a subset of standard container class methods.

Definition at line 7 of file block.h.

Constructor & Destructor Documentation

block()

block::block ( size_t  aBlockSize )

explicit

Allocate block via mmap to ensure proper alignment along page borders, needed for efficient read/write ops.

Definition at line 8 of file block.cpp.

                              :
    bytes(0),
    blockSize(aBlockSize),
    startOffset(0),
    hole(false) {
    buffer = throwcall::badval(mmap(nullptr, blockSize,
                                    PROT_READ | PROT_WRITE,
                                    MAP_PRIVATE | MAP_ANONYMOUS, -1, 0),
                               MAP_FAILED, "can't allocate buffer with size ", blockSize);
}

References throwcall::badval(), blockSize, and buffer.

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~block()

block::~block

(

)

Definition at line 18 of file block.cpp.

              {
    throwcall::good0(munmap(buffer, blockSize), "can't unmap buffer");
}

References blockSize, buffer, and throwcall::good0().

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Member Function Documentation

bufferAt() [1/2]

void * block::bufferAt

(

size_t

offset

)

only way to access the data in the block

Definition at line 28 of file block.cpp.

                                    {
    if (__builtin_expect(hole, false)) {
        throw std::runtime_error("non const bufferAt called for hole block");
    }
    return static_cast<void*>(static_cast<char*>(buffer) + aOffset);
}

References buffer, and hole.

Referenced by copyRequest::base::doUnthreadedCopy(), inputHandler::davix::readerDavix::readBlock(), inputHandler::dcap::readerDcap::readBlock(), inputHandler::daosFs::readerDaosFs::readBlock(), inputHandler::libssh::readerLibssh::readBlock(), inputHandler::dummy::readerDummy::readBlock(), inputHandler::posixFile::readerPosixFile::readBlock(), inputHandler::davix::readerDavix::readBlockP(), inputHandler::daosFs::readerDaosFs::readBlockP(), inputHandler::dummy::readerDummy::readBlockP(), inputHandler::posixFile::readerPosixFile::readBlockP(), outputHandler::davix::writerDavix::writeBlock(), outputHandler::dcap::writerDcap::writeBlock(), outputHandler::libssh::writerLibssh::writeBlock(), outputHandler::posixFile::writerPosixFile::writeBlock(), outputHandler::daosFs::writerDaosFs::writeBlock(), outputHandler::posixFile::writerPosixFile::writeBlockP(), and outputHandler::daosFs::writerDaosFs::writeBlockP().

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bufferAt() [2/2]

const void * block::bufferAt

(

size_t

offset

)

const

only way to access the data in the block

Definition at line 22 of file block.cpp.

                                                {
    if (__builtin_expect(hole, false)) {
        return nullBuffer();
    }
    return static_cast<const void*>(static_cast<char*>(buffer) + aOffset);
}

References buffer, hole, and nullBuffer().

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bump_size()

void block::bump_size ( size_t  additionalBytes )

inline

< increase number of stored bytes

Definition at line 33 of file block.h.

                                           {
        bytes += additionalBytes;   
    }

References bytes.

Referenced by inputHandler::davix::readerDavix::readBlock(), inputHandler::dcap::readerDcap::readBlock(), inputHandler::daosFs::readerDaosFs::readBlock(), inputHandler::libssh::readerLibssh::readBlock(), inputHandler::dummy::readerDummy::readBlock(), inputHandler::posixFile::readerPosixFile::readBlock(), inputHandler::davix::readerDavix::readBlockP(), inputHandler::daosFs::readerDaosFs::readBlockP(), inputHandler::dummy::readerDummy::readBlockP(), and inputHandler::posixFile::readerPosixFile::readBlockP().

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clear()

void block::clear ( size_t  aOffset )

inline

< declares the block as empty, DOES NOT ZERO THE CONTENT

Definition at line 28 of file block.h.

                               {
        startOffset = aOffset;
        bytes = 0;   
        hole = false;
    }

References bytes, hole, and startOffset.

Referenced by inputHandler::davix::readerDavix::readBlock(), inputHandler::dcap::readerDcap::readBlock(), inputHandler::daosFs::readerDaosFs::readBlock(), inputHandler::libssh::readerLibssh::readBlock(), inputHandler::dummy::readerDummy::readBlock(), inputHandler::posixFile::readerPosixFile::readBlock(), inputHandler::davix::readerDavix::readBlockP(), inputHandler::daosFs::readerDaosFs::readBlockP(), inputHandler::dummy::readerDummy::readBlockP(), and inputHandler::posixFile::readerPosixFile::readBlockP().

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empty()

bool block::empty ( ) const

inline

< check if no data are stored

Definition at line 19 of file block.h.

                       {
        return bytes == 0;   
    }

References bytes.

isHole()

bool block::isHole ( ) const

inline

Definition at line 36 of file block.h.

                        {
        return hole;
    }

References hole.

Referenced by copyRequest::base::doUnthreadedCopy(), outputHandler::davix::writerDavix::writeBlock(), outputHandler::dcap::writerDcap::writeBlock(), outputHandler::libssh::writerLibssh::writeBlock(), outputHandler::posixFile::writerPosixFile::writeBlock(), and outputHandler::daosFs::writerDaosFs::writeBlock().

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max_size()

size_t block::max_size ( ) const

inline

< returns capacity of the block

Definition at line 22 of file block.h.

                            {
        return blockSize;   
    }

References blockSize.

Referenced by inputHandler::dummy::DummyDirectory::getNextEntry(), inputHandler::dummy::getStat(), inputHandler::Gpfs::readerGpfs::readBlock(), inputHandler::davix::readerDavix::readBlock(), inputHandler::dcap::readerDcap::readBlock(), inputHandler::daosFs::readerDaosFs::readBlock(), inputHandler::libssh::readerLibssh::readBlock(), inputHandler::dummy::readerDummy::readBlock(), inputHandler::posixFile::readerPosixFile::readBlock(), inputHandler::Gpfs::readerGpfs::readBlockP(), inputHandler::davix::readerDavix::readBlockP(), inputHandler::daosFs::readerDaosFs::readBlockP(), inputHandler::posixFile::readerPosixFile::readBlockP(), outputHandler::Gpfs::writerGpfs::writeBlock(), and outputHandler::Gpfs::writerGpfs::writeBlockP().

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nullBuffer()

const void * block::nullBuffer ( )

static

Definition at line 37 of file block.cpp.

                              {
    static void* nullBuf = nullptr;
    if (nullBuf == nullptr) {
        nullBuf =  throwcall::badval(mmap(nullptr, nullBufferSize(),
                                          PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0),
                                     MAP_FAILED, "can't allocate buffer with size ", nullBufferSize());
        // according no mmap(2) the buffer is zero-filled
    }
    return nullBuf;
}

References throwcall::badval(), and nullBufferSize().

Referenced by bufferAt(), checksum::sslSum::update(), checksum::md5sum::update(), checksum::adler32noOpt::update(), and checksum::crc32::update().

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nullBufferSize()

size_t block::nullBufferSize ( )

static

Definition at line 34 of file block.cpp.

                             {
    return 1024 * 1024 * 16;
}

Referenced by nullBuffer(), checksum::sslSum::update(), checksum::md5sum::update(), checksum::adler32noOpt::update(), checksum::crc32::update(), outputHandler::davix::writerDavix::writeBlock(), and outputHandler::dcap::writerDcap::writeBlock().

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offset()

size_t block::offset ( ) const

inline

< returns offset in the file

Definition at line 25 of file block.h.

                          {
        return startOffset;   
    }

References startOffset.

Referenced by inputHandler::Gpfs::readerGpfs::readBlock(), outputHandler::Gpfs::writerGpfs::writeBlock(), outputHandler::Gpfs::writerGpfs::writeBlockP(), outputHandler::posixFile::writerPosixFile::writeBlockP(), and outputHandler::daosFs::writerDaosFs::writeBlockP().

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setHoleState()

void block::setHoleState ( bool  holeState )

inline

Definition at line 39 of file block.h.

                                      {
        hole = holeState;
    }

References hole.

Referenced by inputHandler::posixFile::readerPosixFile::readBlock().

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size()

size_t block::size ( ) const

inline

< returns number of bytes actually stored here, may exceed blockSize for holes

Definition at line 16 of file block.h.

                        {
        return bytes;   
    }

References bytes.

Referenced by copyRequest::base::doUnthreadedCopy(), inputHandler::davix::readerDavix::readBlock(), inputHandler::dcap::readerDcap::readBlock(), inputHandler::daosFs::readerDaosFs::readBlock(), inputHandler::libssh::readerLibssh::readBlock(), inputHandler::posixFile::readerPosixFile::readBlock(), inputHandler::davix::readerDavix::readBlockP(), inputHandler::daosFs::readerDaosFs::readBlockP(), inputHandler::posixFile::readerPosixFile::readBlockP(), outputHandler::davix::writerDavix::writeBlock(), outputHandler::dcap::writerDcap::writeBlock(), outputHandler::libssh::writerLibssh::writeBlock(), outputHandler::posixFile::writerPosixFile::writeBlock(), outputHandler::daosFs::writerDaosFs::writeBlock(), outputHandler::posixFile::writerPosixFile::writeBlockP(), and outputHandler::daosFs::writerDaosFs::writeBlockP().

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Member Data Documentation

blockSize

size_t block::blockSize

private

capacity of the block

Definition at line 10 of file block.h.

Referenced by block(), max_size(), and ~block().

buffer

void* block::buffer

private

Definition at line 8 of file block.h.

Referenced by block(), bufferAt(), and ~block().

bytes

size_t block::bytes

private

number of bytes actually stored here

Definition at line 9 of file block.h.

Referenced by bump_size(), clear(), empty(), and size().

hole

bool block::hole

private

represents a hole in the file with bytes bytes.

Definition at line 12 of file block.h.

Referenced by bufferAt(), clear(), isHole(), and setHoleState().

startOffset

size_t block::startOffset

private

offset in the file that is represented by this block

Definition at line 11 of file block.h.

Referenced by clear(), and offset().

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

• src/block.h (v0.19-24-g0617ca1 with changes)
• src/block.cpp (v0.19-24-g0617ca1 with changes)