The bitVector class provides an array of bits, similar to QBitArray. More...

#include <bitVector.h>

Classes
class	miniBitVector
	Simple array of bits, useful for static data. More...

Public Member Functions
	bitVector ()
	Constructs an empty bit array.

	bitVector (int numBits)
	Constructs an array of size bits. More...

	bitVector (QByteArray data)
	Constructs a bitVector from a QByteArray. More...

quint8	getBit (int index) const
	Returns the bit at position index. More...

void	setBit (int index, quint8 bit)
	Sets the bit at position index. More...

int	size () const
	Size of the bitVector in bits. More...

void	resize (int newSize)
	Sets the size of the bitVector array to newSize bits. More...

bool	startsWith (const miniBitVector &mbv, int index=0) const
	Check if the content of the given miniBitVector is found at a given position. More...

void	append (const miniBitVector &mbv)
	Appends a miniBitVector to the end of the bitVector. More...

	operator QByteArray ()
	Converts the bitVector to a QByteArray. More...

	operator QString () const
	Convert bitVector to human-readable string. More...

Static Public Member Functions
static quint8	getBit (const quint8 *ptr, int index)
	Convenience method for read access to a bit in a C-array of bytes. More...

static void	setBit (quint8 *ptr, int index, quint8 bit)
	Convenience method for write access to a bit in a C-array of bytes. More...

static void	fill (quint8 *ptr, int startIndex, int numBits, quint8 bit)
	Convenience method for write access to a continuous block of bits in a C-array of bytes. More...

static int	findEndOfRun (const quint8 *ptr, int startIndex, int endIndex, quint8 runValue)
	Searches for end of a run of consecutive bits with same value. More...

Detailed Description

The bitVector class provides an array of bits, similar to QBitArray.

A bitVector is an array that gives access to individual bits. In this respect, the class is very similar to QBitArray. Unlike QBitArray, there are convenient and well-defined conversions from bitVectors to QByteArrays with guraranteed behaviour.

The bitVector class is based on QByteArray, and therefore uses implicit sharing (copy-on-write) to reduce memory usage and to avoid the needless copying of data. The methods of this class are reentrant, but not thread safe.

Warning: The implementation has been tested for correctness, but has not been optimized for speed.

Definition at line 42 of file bitVector.h.

Constructor & Destructor Documentation

◆ bitVector() [1/2]

bitVector::bitVector ( int numBits )

explicit

Constructs an array of size bits.

Parameters

numBits Size of the newly created bit vector

The bit are initialized to the value '0'.

◆ bitVector() [2/2]

bitVector::bitVector ( QByteArray data )

explicit

Constructs a bitVector from a QByteArray.

Constructs an array of 8*data.size() bits. Bit number 0 in the resulting bitVector corresponds to the most significant bit in byte 0 of the QByteArray. Bit number 1 corresponds to the second most significant bit in byte 0 of the QByteArray, etc.

Parameters

data	QByteArray whose data is copied

This operation uses implicit sharing and therefore takes constant time.

Member Function Documentation

◆ append()

void bitVector::append ( const miniBitVector & mbv )

inline

Appends a miniBitVector to the end of the bitVector.

The bitVector will be resized if necessary.

Parameters

mbv	miniBitVector whose content is appended

Definition at line 168 of file bitVector.h.

◆ fill()

static void bitVector::fill	(	quint8 *	ptr,
		int	startIndex,
		int	numBits,
		quint8	bit
	)

inlinestatic

Convenience method for write access to a continuous block of bits in a C-array of bytes.

Parameters

ptr	This is a pointer to an array by bytes (a.k.a. quint8).
startIndex	This must be a valid index position in the bit array. Bit number 0 is the most significant bit in byte 0 of the array. Bit number 1 is the second most significant bit in byte 0 of the array, etc. Indices that point out of the array boundes will likely lead to segfault.
numBits	Number of bits to be written. The array must be at least of size startIndex+numBits, or else a segfault will likely occur.
bit	Either 0 or 1

Definition at line 251 of file bitVector.h.

◆ findEndOfRun()

static int bitVector::findEndOfRun	(	const quint8 *	ptr,
		int	startIndex,
		int	endIndex,
		quint8	runValue
	)

inlinestatic

Searches for end of a run of consecutive bits with same value.

Parameters

ptr	Pointer to the data whose content is searched
startIndex	Index of the first bit to be looked at
endIndex	Index of the last bit to be looked at
runValue	Value of the bits in the run

Returns: Index of the first bit in the interval [startIndex : endIndex-1] that is not of value 'runValue'. If no such bit has been found, 'endIndex' is returned.

Definition at line 304 of file bitVector.h.

◆ getBit() [1/2]

static quint8 bitVector::getBit	(	const quint8 *	ptr,
		int	index
	)

inlinestatic

Convenience method for read access to a bit in a C-array of bytes.

Parameters

ptr	This is a pointer to an array by bytes (a.k.a. quint8).
index	Number of the bit that is retrieved from the array. Bit number 0 is the most significant bit in byte 0 of the array. Bit number 1 is the second most significant bit in byte 0 of the array, etc. Indices that point out of the array boundes will likely lead to segfault.

Returns: Either 0 or 1

Definition at line 212 of file bitVector.h.

◆ getBit() [2/2]

quint8 bitVector::getBit ( int index ) const

inline

Returns the bit at position index.

Parameters

index This must be a valid index position in the bit array. In other words, index < size(). Invalid values will likely lead to segfault

Returns: Either 0 or 1

Definition at line 77 of file bitVector.h.

◆ operator QByteArray()

bitVector::operator QByteArray ( )

Converts the bitVector to a QByteArray.

Stores the bitVector in an array of (size()+7)/8 bytes. Bit number 0 in the bitVector corresponds to the most significant bit in byte 0 of the QByteArray. Bit number 1 corresponds to the second most significant bit in byte 0 of the QByteArray, etc. Unused bits in the last byte of the resulting array are set to zero.

Returns: QByteArray containing the bitvector data

◆ operator QString()

bitVector::operator QString ( ) const

Convert bitVector to human-readable string.

Returns: QString describing the bitVector

◆ resize()

void bitVector::resize ( int newSize )

Sets the size of the bitVector array to newSize bits.

If size is greater than the current size, the bitVector is extended by adding the extra bits to the end. The new bits are uninitialized. If newSize is less than the current size, bits are removed from the end.

Parameters

newSize New size of the vector, in bits

◆ setBit() [1/2]

void bitVector::setBit	(	int	index,
		quint8	bit
	)

inline

Sets the bit at position index.

Parameters

index	This must be a valid index position in the bit array. In other words, index < size(). Invalid values for index will likely lead to segfault
bit	Bit value, either 0 or 1.

Definition at line 89 of file bitVector.h.

◆ setBit() [2/2]

static void bitVector::setBit	(	quint8 *	ptr,
		int	index,
		quint8	bit
	)

inlinestatic

Convenience method for write access to a bit in a C-array of bytes.

Parameters

ptr	This is a pointer to an array by bytes (a.k.a. quint8).
index	This must be a valid index position in the bit array. Bit number 0 is the most significant bit in byte 0 of the array. Bit number 1 is the second most significant bit in byte 0 of the array, etc. Indices that point out of the array boundes will likely lead to segfault.
bit	Either 0 or 1

Definition at line 227 of file bitVector.h.

◆ size()

int bitVector::size ( ) const

inline

Size of the bitVector in bits.

Returns: Size of the bitVector, in number of bits

Definition at line 101 of file bitVector.h.

◆ startsWith()

bool bitVector::startsWith	(	const miniBitVector &	mbv,
		int	index = `0`
	)		const

Check if the content of the given miniBitVector is found at a given position.

Parameters

mbv	miniBitVector whose content is expected to by found at position index
index	Position where the content of mbv is expected

Returns: True if the content of the given miniBitVector is found a position index; otherwise returns false

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

/home/kebekus/Software/projects/scantools/src/libscantools/bitVector.h

Classes

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ bitVector() [1/2]

◆ bitVector() [2/2]

Member Function Documentation

◆ append()

◆ fill()

◆ findEndOfRun()

◆ getBit() [1/2]

◆ getBit() [2/2]

◆ operator QByteArray()

◆ operator QString()

◆ resize()

◆ setBit() [1/2]

◆ setBit() [2/2]

◆ size()

◆ startsWith()