build_lrec.c

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/*===========================================================================*/
/* DMC Interim out |             build_lrec                |    SEED Headers */
/*===========================================================================*/
/*
	Name:		build_lrec
	Purpose:	construct SEED logical records from properly-sized data streams
	Usage:		void build_lrec ();
				char *header_data;
				char type;
				int continuation;
				int length;
				build_lrec (header_data, type, continuation, length);
	Input:		header_data = ptr to beginning of a data stream
				type = a valid SEED data type (V, A, S, T, D)
				continuation = continuation flag (TRUE or FALSE)
				length = number of characters in input data stream
	Output:		none
	Externals:	Debug - setting of environment variable DEBUG (globals.h)
				Headers_head and Headers_tail
	Messages:	none
	Warnings:	none
	Errors:		none
	Fatals:		none
	Called by:	make_lrec
	Calls to:	error_handler - handle error conditions
	Algorithm:	receive a datastream of at most LRECL - 8 characters;
				allocate space for a logical record; put the 6 character
				sequence number spaceholder (all zeroes), the data type, and
				' ' or '*' as continuation flag into the record; put the
				data stream into the record.  Link the result into the
				header linked list.
	Notes:		none
	Problems:	none known
	Debug:		level D_MIN - print out start and finish notices
				level D_MED -
				level D_MAX -
	References:	none
	Language:	C, more or less ANSI standard, under Sun OS 3.5
	Revisions:	03/03/89  Dennis O'Neill  original version
				03/06/89 mark wiederspahn re-written
*/

#include "output.h"

int build_lrec (header_data, type, continuation, length )
char *header_data;								/* ptr to data stream */
char type;										/* SEED block type */
int continuation;								/* continuation flag */
int length;										/* length of input string */
{
	char *header;								/* output stream */
	register char *p;							/* buffer fill ptr */
	int error;									/* error value */


	error = FALSE;
	if (Debug >= D_MIN) fprintf (D_OUT, "[build_lrec] Started.\n");

	if( length < 0 || length > Lrecl-8 )
	{
		error = error_handler( FATAL,"[build_lrec] length bad");
		return( error );
	}

                   /*=====================================*/
/*=================|   allocate space for logical record   |=================*/
                   /*=====================================*/

	if ((header = (char *) malloc (Lrecl * sizeof (char))) == NULL)
	{
		error = error_handler (FATAL,
			"[build_lrec] Unable to malloc sufficient space.");
		return( error );
	}

                   /*=====================================*/
/*=================|          construct leader             |=================*/
                   /*=====================================*/

	strncpy( header, "000000", 6 );
	*(header+6) = type;
	*(header+7) = continuation ? '*' : SPACE ;

                   /*=====================================*/
/*=================|      put data into logical record     |=================*/
                   /*=====================================*/

	if( length > 0 ) memcpy( header+8, header_data, length );

	/* if necessary, blank-pad out to logical record length */

	p = header+8+length;
	length = (Lrecl-8) - length;
	while( length-- ) *p++ = SPACE;

                   /*=====================================*/
/*=================|     link logical record into list     |=================*/
                   /*=====================================*/
/*
 * create and link a node into list, set it to point to our new log rec
 */

	(void)make_logrec( &Headers_head, &Headers_tail );
	Headers_tail->record = header;

	if( Debug >= D_MIN ) fprintf (D_OUT, "[build_lrec] Completed.\n");
	return( error );
}