dld.c

#if 0
/*===========================================================================
	D L D . C

	Declarations and definitions:

	Rockwell 6502 format records.

	The data is recorded as a series of ASCII records. The format of the
	records is as follows:

	   ;ccaaaadddd...chks

	where ";" is the record sentinal, "cc" is the count of the number of binary
	bytes of data in the record, "aaaa" is the 16 bit load address of byte 0
	in the record, "dd" are bytes of data and "chks" is the 16-bit checksum
	of the count, address, and data converted to bytes.

	All binary bytes in the record are checksumed with 8-bit precision
	including the count and each byte of the 2 byte load address, and the type
	field. All values are expressed in hex and there is 1 ASCII character for
	each 4 bit nibble.

	Whitespace is ignored.

	Copyright 1989 Atari Games.  All rights reserved.
	Author: Lyle Rains

---------------------------------------------------------------------------
Revision history:

---------------------------------------------------------------------------
Known bugs/features/limitations:

===========================================================================*/
#endif

/* #define SHOSTUFF */

#include "mixit.h"

/*==========================================================================*/
int GetRec_dld(InRecord *rec)
{
	int		cnt, datacnt, chk, c;
	uchar	*inbuf = rec->recBuf;
	uchar	* lookahead,*bufend,*data;

	if ( fgets((char *)inbuf, rec->recBufLen, rec->recFile) == NULL )
	{
		rec->recLen = 0;
		return (rec->recType = feof(rec->recFile) ? REC_EOF : REC_ERR);
	}

	/*	Convert to 'pure' hexidecimal record:  purge everything until a ';',
	 *	squeeze out junk, and quit when you find end of record.
	 */

	lookahead = bufend = inbuf;
	c = 0;
	while ( *lookahead != 0 )
	{
		if ( c )
		{
			if ( isxdigit(*bufend = *lookahead) )
				++bufend;
		}
		else if ( *lookahead == ';' )
			c = 1;
		++lookahead;
	}
	if ( (cnt = bufend - inbuf) == 0 )
	{
		rec->recLen = 0;
		return (rec->recType = REC_UNKNOWN)/* empty line */;
	}
	cnt /= 2;

	/* Convert to byte string. */

	SHOW( *bufend = 0;
		 fputs((char *)inbuf, errFile);
		 putc('\n', errFile);
		)
	strtobytes(inbuf, cnt);
	bufend = inbuf + cnt;
	SHOW(	for ( data = inbuf; data < bufend; ++data )
			 fprintf(errFile, "%.2X", *data);
		 putc('\n', errFile);
		 )
	/* Get count, addr, and record type. */

	datacnt = inbuf[0];
	rec->recSAddr = bytestoaddr(&inbuf[1], 2);
	SHOW( fprintf(errFile, "addr = %.4X\n", rec->recSAddr);
		 )

	/* Verify record length and checksum. */

	if ( datacnt > cnt - 5 /* 1-byte count, 2-byte addr, 2-bytes chksum */ )
	{
		moan("Record length error (sez %d, is %d)", datacnt, cnt - 5);
		rec->recLen = 0;
		return (rec->recType = REC_ERR);
	}
	chk = 0;
	for ( data = inbuf; data < bufend - 2; ++data )
		chk += *data;
	SHOW( fprintf(errFile, "chk = 0x%.2X\n", chk);
		 )
	if ( (LogicalAddr)(chk & 0xFFFF) != bytestoaddr(bufend - 2, 2) )
	{
		moan("Checksum error");
		rec->recLen = 0;
		return (rec->recType = REC_ERR);
	}
	rec->recLen = datacnt;
	rec->recData = inbuf + 3 /* skip header */;
	rec->recEAddr = rec->recSAddr+datacnt-1;
	return (rec->recType = datacnt ? REC_DATA : REC_UNKNOWN /* EOF record */);

} /* end GetRec_dld */

/*==========================================================================*
 * Outputs a single record in DLD format.
 *==========================================================================*/
int PutRec_dld(FILE *file, uchar *data, int recsize, ulong recstart)
{
	int		j;
	char	*cp;
	char	outbuf[512];
	uint	cksum;
#if 0
	int		recbytes;

	recbytes = recsize + 3;
#endif
	cp  = outbuf;
	sprintf(cp, ";%02X%04lX", recsize, recstart & 0xFFFF);
	cp += strlen(cp);

	/* Append data to the record */
	cksum = recsize + ((recstart >> 8) & 0xFF) + (recstart & 0xFF);
	for ( j = 0; j < recsize; ++j )
	{
		cksum += *data;
		cp     = to_hex(*data++, cp);
	}       /* end each record */
	/* Append the checksum */
	sprintf(cp, "%04X\n", cksum & 0xFFFF);
	fputs(outbuf, file);    /* Output the record to the file */

	return 1;

} /* end PutRec_dld */

/*==========================================================================*
 * Outputs all footer information required by a DLD format file.
 *==========================================================================*/
int PutFoot_dld(FILE *file)
{
	fputs(";0000000000\n", file);
	return 1;
} /* end PutFoot_dld */