rtxBitEncode.h File Reference

Bit encode functions. More...

#include "rtxsrc/rtxContext.h"

Go to the source code of this file.

Macros
#define	rtxEncByteAlignPattern(pctxt, pattern)
	This macro will byte-align the context buffer by encoding according to the given pattern. More...

Functions
EXTERNRT int	rtxEncBitsPattern (OSCTXT *pctxt, OSUINT8 pattern, OSSIZE nbits)
	This function encodes the given number of bits using a repeating bit pattern. More...
EXTERNRT int	rtxEncBit (OSCTXT *pctxt, OSBOOL value)
	This function will set the bit at the current encode bit cursor position to 1 or 0 and advance the cursor pointer. More...
EXTERNRT int	rtxEncBits (OSCTXT *pctxt, OSUINT32 value, OSSIZE nbits)
	This function encodes a number of the least significant bits (up to 32) of an unsigned integer value. More...
EXTERNRT int	rtxEncBitsFromSize (OSCTXT *pctxt, OSSIZE value, OSSIZE nbits)
	This function encodes a number of the least significant bits from a size type. More...
EXTERNRT int	rtxEncBitsFromByteArray (OSCTXT *pctxt, const OSOCTET *pvalue, OSSIZE nbits)
	This function will encode a series of bits from an octet array. More...
EXTERNRT int	rtxCopyBits (OSCTXT *pctxt, const OSOCTET *pvalue, OSSIZE nbits, OSUINT32 bitOffset)
	This function will encode a series of bits from an octet array. More...
EXTERNRT int	rtxMergeBits (OSCTXT *pctxt, OSUINT32 value, OSSIZE nbits)
	This function will merge a series of bits (up to 32) from an unsigned integer value into an existing encoded data buffer. More...

Detailed Description

Bit encode functions.

Definition in file rtxBitEncode.h.

Macro Definition Documentation

rtxEncByteAlignPattern

#define rtxEncByteAlignPattern	(		pctxt,
			pattern
	)

Value:

if ((pctxt)->buffer.bitOffset != 8) { \
   rtxEncBits(pctxt, pattern, (pctxt)->buffer.bitOffset); }

This macro will byte-align the context buffer by encoding according to the given pattern.

If the buffer is not aligned, the lowest bits of the current byte, which have not be written already, will be set to the corresponding lowest bites of the pattern.

Definition at line 44 of file rtxBitEncode.h.

Function Documentation

rtxCopyBits()

EXTERNRT int rtxCopyBits	(	OSCTXT *	pctxt,
		const OSOCTET *	pvalue,
		OSSIZE	nbits,
		OSUINT32	bitOffset
	)

This function will encode a series of bits from an octet array.

Encoding started from specified bit offset.

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
pvalue	Pointer to bit string to be encoded.
nbits	Number of bits from the value to encode.
bitOffset	Starting bit offset.

Returns

Status of the operation. Zero if successful; a negative status code if failed.

rtxEncBit()

EXTERNRT int rtxEncBit	(	OSCTXT *	pctxt,
		OSBOOL	value
	)

This function will set the bit at the current encode bit cursor position to 1 or 0 and advance the cursor pointer.

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
value	The value to be encoded.

rtxEncBits()

EXTERNRT int rtxEncBits	(	OSCTXT *	pctxt,
		OSUINT32	value,
		OSSIZE	nbits
	)

This function encodes a number of the least significant bits (up to 32) of an unsigned integer value.

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
value	The value to be encoded.
nbits	Number of bits from the value to encode.

Returns

Status of the operation. Zero if successful; a negative status code if failed.

rtxEncBitsFromByteArray()

EXTERNRT int rtxEncBitsFromByteArray	(	OSCTXT *	pctxt,
		const OSOCTET *	pvalue,
		OSSIZE	nbits
	)

This function will encode a series of bits from an octet array.

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
pvalue	Pointer to bit string to be encoded.
nbits	Number of bits from the value to encode.

Returns

Status of the operation. Zero if successful; a negative status code if failed.

rtxEncBitsFromSize()

EXTERNRT int rtxEncBitsFromSize	(	OSCTXT *	pctxt,
		OSSIZE	value,
		OSSIZE	nbits
	)

This function encodes a number of the least significant bits from a size type.

The maximum that may be encoded is the maximum held by the type (32 or 64 bits).

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
value	The value to be encoded.
nbits	Number of bits from the value to encode.

Returns

Status of the operation. Zero if successful; a negative status code if failed.

rtxEncBitsPattern()

EXTERNRT int rtxEncBitsPattern	(	OSCTXT *	pctxt,
		OSUINT8	pattern,
		OSSIZE	nbits
	)

This function encodes the given number of bits using a repeating bit pattern.

This function may be used to encode any number of bits (including more than 8 bits). It will take the bit values to encode from the pattern, in accordance with the buffer's bit offset. For example, if the next bit to encode is the highest bit of the next byte in the buffer, then the bit value encoded will be the highest bit of the pattern.

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
pattern	The repeating pattern.
bits	The number of bits to encode.

rtxMergeBits()

EXTERNRT int rtxMergeBits	(	OSCTXT *	pctxt,
		OSUINT32	value,
		OSSIZE	nbits
	)

This function will merge a series of bits (up to 32) from an unsigned integer value into an existing encoded data buffer.

Parameters

pctxt	Pointer to a context structure. This provides a storage area for the function to store all working variables that must be maintained between function calls.
value	The value to be encoded.
nbits	Number of bits from the value to merge.

Returns

Status of the operation. Zero if successful; a negative status code if failed.