Functions for input and output to/from a bitstream

Functions
int	bitio_i_open (void *buf, size_t size)
	This function opens a bitstream for input.
int	bitio_i_input (int handle, unsigned long *val, int nbits)
	This function reads a value from a bitstream.
void	bitio_i_close (int handle)
	Closes an bitstream that was opened for input.
int	bitio_o_open ()
	Opens a bitstream for output.
long	bitio_o_append (int handle, unsigned long val, int nbits)
	This function appends a value to a bitstream.
void	bitio_o_outp (int handle, unsigned long val, int nbits, long bitpos)
	This function outputs a value to a specified position of a bitstream.
size_t	bitio_o_get_size (int handle)
	Returns the size of an output-bitstream (number of bytes).
void *	bitio_o_close (int handle, size_t *nbytes)
	This function closes an output-bitstream.

---

Function Documentation

int bitio_i_open	(	void *	buf,
		size_t	size
	)

This function opens a bitstream for input.

Parameters:

[in]	buf	Buffer to be used for input
[in]	size	Size of buffer.

Returns:

the function returns a handle by which the bitstream can be identified for all subsequent actions or -1 if the maximum number of opened bitstreams exceeds.

See also:

bitio_i_close, bitio_i_input, bitio_o_open

Definition at line 162 of file bitio.c.

int bitio_i_input	(	int	handle,
		unsigned long *	val,
		int	nbits
	)

This function reads a value from a bitstream. The bitstream must have been opened by bitio_i_open.

Parameters:

[in]	handle	Identifies the bitstream.
[out]	val	Is where the input-value is stored.
[in]	nbits	Number of bits the value consists of.

Returns:

Returns 1 on success or 0 on a fault (number of bytes in the bitstream exceeded).

See also:

bitio_i_open, bitio_i_close, bitio_o_outp

Definition at line 207 of file bitio.c.

void bitio_i_close

(

int

handle

)

Closes an bitstream that was opened for input

Parameters:

[in]

handle

Handle that identifies the bitstream.

See also:

bitio_i_open, bitio_i_input

Definition at line 254 of file bitio.c.

int bitio_o_open

(

)

This function opens a bitstream for output.

Returns:

The return-vaule is a handle by which the bit-stream can be identified for all subesquent actions or -1 if there is no unused bitstream available.

Definition at line 271 of file bitio.c.

long bitio_o_append	(	int	handle,
		unsigned long	val,
		int	nbits
	)

This function appends a value to a bitstream which was opened by bitio_o_open.

Parameters:

[in]	handle	Indicates the bitstream for appending.
[in]	val	Value to be output.
[in]	nbits	Number of bits of val to be output to the stream.

Note:

nbits must be less than sizeof (long)

Returns:

The return-value is the bit-position of the value in the bit-stream, or -1 on a fault.

See also:

bitio_o_open, bitio_o_close, bitio_o_outp

Definition at line 322 of file bitio.c.

void bitio_o_outp	(	int	handle,
		unsigned long	val,
		int	nbits,
		long	bitpos
	)

This function outputs a value to a specified position of a bitstream.

Parameters:

[in]	handle	Indicates the bitstream for output.
[in]	val	Value to be output.
[in]	nbits	Number of bits of val to be output to the stream.
[in]	bitpos	bitposition of the value in the bitstream.

Note:

nbits must be less then sizeof (long)

See also:

bitio_o_open, bitio_o_close, bitio_o_append, bitio_i_input

Definition at line 366 of file bitio.c.

size_t bitio_o_get_size

(

int

handle

)

This function returns the size of an output-bitstream (number of bytes)

Parameters:

[in]

handle

Identifies the bitstream

Returns:

Size of the bitstream.

See also:

bitio_o_open, bitio_o_outp, bitio_o_append

Definition at line 421 of file bitio.c.

void* bitio_o_close	(	int	handle,
		size_t *	nbytes
	)

This function closes an output-bitstream identified by handle and returns a pointer to the memory-area holding the bitstream.

Parameters:

[in]	handle	Bit-stream-handle
[out]	nbytes	number of bytes in the bitstream.

Returns:

The funcion returns a pointer to the memory-area holding the bit-stream or NULL if an invalid handle was specified. The memory area must be freed by the calling function.

See also:

bitio_o_open, bitio_o_outp, bitio_o_append, bitio_i_close

Definition at line 448 of file bitio.c.

---