#include <bit-stream-utils.8byte.h>

Collaboration diagram for impala::BitWriter_8byte:

Public Member Functions
	BitWriter_8byte (uint8_t *buffer, int buffer_len)

void	Clear ()

uint8_t *	buffer () const

int	buffer_len () const

int	bytes_written () const

bool	PutValue (uint64_t v, int num_bits)

template<typename T >
bool	PutAligned (T v, int num_bits)
	Writes v to the next aligned byte. More...

bool	PutVlqInt (int32_t v)

uint8_t *	GetNextBytePtr (int num_bytes=1)

Private Attributes
uint64_t *	buffer_

int	max_bytes_

int	offset_

int	bit_offset_

Detailed Description

Utility class to write bit/byte streams. This class can write data to either be bit packed or byte aligned (and a single stream that has a mix of both). This class does not allocate memory.

Definition at line 30 of file bit-stream-utils.8byte.h.

Constructor & Destructor Documentation

impala::BitWriter_8byte::BitWriter_8byte	(	uint8_t *	buffer,
		int	buffer_len
	)

inline

buffer: buffer to write bits to. Buffer should be preallocated with 'buffer_len' bytes. 'buffer_len' must be a multiple of 8.

Definition at line 34 of file bit-stream-utils.8byte.h.

Member Function Documentation

uint8_t* impala::BitWriter_8byte::buffer ( ) const

inline

Definition at line 48 of file bit-stream-utils.8byte.h.

References buffer_.

int impala::BitWriter_8byte::buffer_len ( ) const

inline

Definition at line 49 of file bit-stream-utils.8byte.h.

References max_bytes_.

int impala::BitWriter_8byte::bytes_written ( ) const

inline

Definition at line 51 of file bit-stream-utils.8byte.h.

References bit_offset_, impala::BitUtil::Ceil(), and offset_.

Referenced by GetNextBytePtr().

void impala::BitWriter_8byte::Clear ( )

inline

Definition at line 42 of file bit-stream-utils.8byte.h.

References bit_offset_, buffer_, max_bytes_, and offset_.

uint8_t * impala::BitWriter_8byte::GetNextBytePtr ( int num_bytes = 1 )

inline

Get a pointer to the next aligned byte and advance the underlying buffer by num_bytes. Returns NULL if there was not enough space.

Definition at line 45 of file bit-stream-utils.8byte.inline.h.

References bit_offset_, buffer_, bytes_written(), max_bytes_, offset_, impala::BitUtil::RoundUpNumBytes(), and UNLIKELY.

Referenced by PutAligned().

template<typename T >

bool impala::BitWriter_8byte::PutAligned	(	T	v,
		int	num_bits
	)

inline

Writes v to the next aligned byte.

Definition at line 65 of file bit-stream-utils.8byte.inline.h.

References GetNextBytePtr(), and PutValue().

bool impala::BitWriter_8byte::PutValue	(	uint64_t	v,
		int	num_bits
	)

inline

Writes a value to the buffer. This is bit packed. Returns false if there was not enough space.

Definition at line 23 of file bit-stream-utils.8byte.inline.h.

References bit_offset_, buffer_, max_bytes_, offset_, and UNLIKELY.

Referenced by PutAligned(), and TestBitWriter8ByteEncode().

bool impala::BitWriter_8byte::PutVlqInt ( int32_t v )

inline

Write a Vlq encoded int to the buffer. Returns false if there was not enough room. The value is written byte aligned. For more details on vlq: en.wikipedia.org/wiki/Variable-length_quantity

Definition at line 76 of file bit-stream-utils.8byte.inline.h.