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GLAST/LAT > DAQ and FSW > FSW > Doxygen Index > QSE / V1-6-3

Constituent: qsd     Tag: sun-gcc

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CCSDS_istream.c File Reference

Input CCSDS packets. More...

#include "QSE/CCSDS_istream.h"
#include "QSE/CCSDS_apidDsc.h"
#include "CCSDS/CCSDS_pkt.h"
#include "MSG/MSG_macdefs.h"
#include "PBS/BSWP.h"
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <errno.h>
#include <sys/time.h>

Include dependency graph for CCSDS_istream.c:

Data Structures
struct	_CCSDS_istreamInput
	Function callbacks to read and close an input stream. More...
struct	_CCSDS_istream
	The control structure/context for reading a CCSDS formatted stream of bytes. More...
Defines
#define	CCSDS_M_SEQ   0x3fff
	Mask of the valid bits in the CCSDS sequence number.
#define	SA_UTB_OFFSET   0x3a4fc880
	The offset between Spectrum-Astro Epoch and UTB.
Typedefs
typedef _CCSDS_istreamInput	CCSDS_istreamInput
	Typedef for struct _CCSDS_istreamInput.
Functions
static __inline void	swapToBig (unsigned int *a32, int n32)
	Halfword swaps the specified number of 32-bit integers to big endian representation. This is a NOOP on big endian machines.
static int __inline	form_transition (unsigned int siv, unsigned short int flags)
	Forms the new state transition word. This consists of 2 bits defining the previous packet state (ONLY, FIRST, MIDDLE, LAST) and 2 bits defining the current packet state.
static int __inline	check_transition (unsigned int state)
	Checks that the transition from the previous state to the current state is allowed.
static int	file_read (FILE *file, unsigned char *buf, int nbytes, int pbytes)
	Simple routine to do a file read using fread.
static CCSDS_istream *	construct (CCSDS_istream *istream, int free)
	Construct for a newly minted CCSDS_istream structure.
int	CCSDS_istreamSizeof (void)
	Returns the size, in bytes, of a CCSDS_istream structure.
CCSDS_istream *	CCSDS_istreamNew (void)
	Convenience function to allocate and initialize a CCSDS_istream control structure.
int	CCSDS_istreamConstruct (CCSDS_istream *istream)
	Constructs (initializes) a previously uninitialized CCSDS_istream control structure.
int	CCSDS_istreamConnect (CCSDS_istream *istream, void *prm, CCSDS_istreamReader read, CCSDS_istreamCloser close, CCSDS_istreamTeller tell)
	Connects a read mechanism with the specified stream.
int	CCSDS_istreamHdrRead (CCSDS_istream *istream, CCSDS_istreamHdr *hdr)
	Reads the CCSDS header.
int	CCSDS_istreamDatRead (CCSDS_istream *istream, const CCSDS_istreamHdr *hdr, CCSDS_apidDsc *dsc)
	Reads the current CCSDS data payload into the buffer specified by dsc.
int	CCSDS_istreamFileOpen (CCSDS_istream *istream, const char *filename, unsigned int options, unsigned char *buf, unsigned int buf_size)
	Convenience function to construct a CCSDS_istream to read from the specified named file filename.
unsigned int	CCSDS_istreamTell (const CCSDS_istream *istream)
	Returns the current byte offset into the stream.
int	CCSDS_istreamClose (CCSDS_istream *istream)
	Closes the input stream associated with istream.
int	CCSDS_istreamDestroy (CCSDS_istream *istream)
	Destroys (i.e. returns the resources) associated with the stream.
void	CCSDS_istreamHdrPrint (const CCSDS_istreamHdr *hdr)
	Prints a one-line summary of the CCSDS_istream header.

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Detailed Description

Input CCSDS packets.

Author:

JJRussell - russell@slac.stanford.edu

   CVS $Id: CCSDS_istream.c,v 1.7 2006/05/08 17:47:08 russell Exp $

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Define Documentation

#define SA_UTB_OFFSET   0x3a4fc880

The offset between Spectrum-Astro Epoch and UTB. Parameters: SA_UTB_OFFSET

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Function Documentation

int CCSDS_istreamClose (  CCSDS_istream *  istream  )

Closes the input stream associated with istream. Returns: Status Parameters: istream  The stream to close Note: This does not free/destroy the istream control structure, it merely closes the physical stream associated with it.

int CCSDS_istreamConnect (  CCSDS_istream *  istream, void *  prm, CCSDS_istreamReader  read, CCSDS_istreamCloser  close, CCSDS_istreamTeller  tell )

Connects a read mechanism with the specified stream. Return values: 0,Always  Parameters: istream  The target CCSDS_istream prm  Arbitrary user context parameter passed to the read routine read  The routine used to read from the underlying physical data stream close  The routine used to close the underlying physical stream tell  The routine used to get the current position in the stream.

int CCSDS_istreamConstruct (  CCSDS_istream *  istream  )

Constructs (initializes) a previously uninitialized CCSDS_istream control structure. Return values: ==0,Successful  !=0,Failure  (currently the routine always succeeds Parameters: istream  The CCSDS_istream structure to construct (initialize)

int CCSDS_istreamDatRead (  CCSDS_istream *  istream, const CCSDS_istreamHdr *  hdr, CCSDS_apidDsc *  dsc )

Reads the current CCSDS data payload into the buffer specified by dsc. Returns: The State Information Vector. This is a heavily bit-encoded 32-bit word, see CCSDS_ISTREAM_SIV_M, for example for the meanings of these bits. Consult the dsc->status word for more information Parameters: istream  The target CCSDS_istream structure hdr  The header associated with the data about to be read dsc  The target APIDs descriptor If there was insufficient space in the descriptor's read buffer to perform the read, no bytes are read, but rather, the return value is set to indicate insufficient space and the descriptor's status word (dsc->status) is set to the number of bytes needed. The user may increase the descriptors read buffer side and then recall this routine.

int CCSDS_istreamDestroy (  CCSDS_istream *  istream  )

Destroys (i.e. returns the resources) associated with the stream. Returns: Status Parameters: istream  The stream to destroy.

int CCSDS_istreamFileOpen (  CCSDS_istream *  istream, const char *  filename, unsigned int  options, unsigned char *  buf, unsigned int  buf_size )

Convenience function to construct a CCSDS_istream to read from the specified named file filename. Returns: 0, If successful -1, If could not allocate a new stream (i.e. out of memory) -2, If the file does not exist XS Parameters: istream  The target CCSDS_istream filename  The name of the file to open options  Bit list of options, currently unused, specify as 0 buf  Optional parameter specifying the FILE's input read buffer buf_size  Optional parameter specifying the size of buf

void CCSDS_istreamHdrPrint (  const CCSDS_istreamHdr *  hdr  )

Prints a one-line summary of the CCSDS_istream header. Parameters: hdr  The header to print

int CCSDS_istreamHdrRead (  CCSDS_istream *  istream, CCSDS_istreamHdr *  hdr )

Reads the CCSDS header. Return values: 0,Success  -1,End  Of Stream Anything  else, error number (errno) Parameters: istream  The target CCSDS_istream hdr  The destination CCSDS header

CCSDS_istream * CCSDS_istreamNew (  void   )

Convenience function to allocate and initialize a CCSDS_istream control structure. Returns: Pointer to the allocated CCSDS_istream control structure

int CCSDS_istreamSizeof (  void   )

Returns the size, in bytes, of a CCSDS_istream structure. Returns: The size, in bytes, of a CCSDS_istream structure

unsigned int CCSDS_istreamTell (  const CCSDS_istream *  istream  )

Returns the current byte offset into the stream. Returns: The current byte offset into the stream, i.e. the read pointer Parameters: istream  The target CCSDS_istream

static int __inline check_transition (  unsigned int  state  )  [static]

Checks that the transition from the previous state to the current state is allowed. Return values: 0,Transition  is allowed !=0,Transition  is not allowed Parameters: state  The 4-bit state transition word This routine checks that the transition from the transition of the previous packet to the state of the current packet is allowed.

static CCSDS_istream * construct (  CCSDS_istream *  istream, int  free )  [static]

Construct for a newly minted CCSDS_istream structure. Returns: istream Parameters: istream  The structure to initialize free  If non-zero, this structure should be freed by CCSDS_istreamFree

static int file_read (  FILE *  file, unsigned char *  buf, int  nbytes, int  pbytes )  [static]

Simple routine to do a file read using fread. Return values: 0,Success  -1,End  Of Stream Anything  else, error number (errno) Parameters: file  The file stream to read from buf  The buffer, guaranteed to be nbytes in length nbytes  The number of data bytes pbytes  The number of pad bytes, these bytes should be discarded This number is guaranteed to be no larger than 16.

static int __inline form_transition (  unsigned int  siv, unsigned short int  flags )  [static]

Forms the new state transition word. This consists of 2 bits defining the previous packet state (ONLY, FIRST, MIDDLE, LAST) and 2 bits defining the current packet state. Parameters: siv  The state information vector containing the state of the previous packet flags  The flags bit of current CCSDS packet as returned by the CCSDS packet query routines The state of packet is defined as ONLY packet or the FIRST, MIDDLE of LAST of a sequence.

void swapToBig (  unsigned int *  a32, int  n32 )  [static]

Halfword swaps the specified number of 32-bit integers to big endian representation. This is a NOOP on big endian machines. Parameters: a32  The array of words to swap n32  The number of words to half_word swap

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