/*======================================================================*
 *                                                                      *
 *                              Ymodem send a single file.                                              *
 *                                                                      *
 *======================================================================*/

#version        $50
#address        $7000
#reserve        6
#copyright      "Ymsend.cmd       Copyright 1995 K-Products"


#include        runtime.h
#include        bbs_pro.h

#define         DISK_2          2
#define         MODEM           5
#define         C_ACK           6
#define         C_NAK           21
#define         C_SOH           1
#define         C_STX           2
#define         C_EOT           4
#define         C_CAN           24
#define         C_TIMEOUT       256
#define         MAX_BUFF        12288

byte    sdmctl  = 559;
byte    console = 53279;

int             current_block;                                  /* block we're currently on             */
int             bytes_in_buffer;
int             buffer_idx;
int             packet_size;
byte    crc_mode;                                               /* 0 = standard, 1 = CRC                */
byte    tries;                                                  /* tries at current block               */

char    buffer [MAX_BUFF];


main()
{
	cr_lf();
	if (parm1 [0] == 0) {
		echose("Parameter error!");
		cr_lf();
		echose("Use YMSEND filename.ext");
		aborted = 1;
		return;
	}
	MIOsuspend();
	if (open (DISK_2, parm1, 4, 0) != OK) {
		MIOresume();
		echose("That file doesn't exist!");
		aborted = 1;
		return;
	}
	MIOresume();
	send_file();
	MIOsuspend();
	close (DISK_2);
	MIOresume();
}



send_file()
{
	int     ch, crc;
	packet_size             = 1024;
	bytes_in_buffer = MAX_BUFF;
	buffer_idx              = MAX_BUFF;
	current_block   = 1;
	tries                   = 0;
	MIOresume();
	echos ("File ");
	echos (parm2);
	echose(" ready to send");
	cr_lf();
	while ( 1 ) {
		++tries;
		if (baud < 3)                                           /* if < 4800 baud       */
			printf("%cSending block %d/%d/1024 ", $9c, current_block, tries);
		if (tries > 10) {
			printf("%eToo many errors!%e");
			aborted = 1;
			return;
		}
		ch = com_getc(50);
		case ( ch ) {
			C_TIMEOUT       :       {
							aborted = 1;
							return;
							}
			C_ACK           :       {
					tries = 0;
							++current_block;
							buffer_idx = buffer_idx + packet_size;
							}
			C_NAK           :       if (current_block == 1)
								crc_mode = 0;
			'C'                     :       if (current_block == 1)
								crc_mode = 1;
			C_CAN           :       {
							printf ("%eReceiver aborted..");
							aborted = 1;
							return;
							}
			else            :       {
							if (check_carrier() == 1) {
								printf("%eCarrier dropped!%e");
								aborted = 1;
								return;
							}
							purge_modem();
							}
		}
		if ( buffer_idx >= bytes_in_buffer ) {
			if ( bytes_in_buffer < MAX_BUFF ) {
				signal_EOT();
				aborted = 0;
				return;
			 }
			else {
				MIOsuspend();
				setblock (buffer, MAX_BUFF, $1a);
				bytes_in_buffer = blockread (DISK_2, buffer, MAX_BUFF);
				if (IOresult (DISK_2) != 1 && IOresult (DISK_2) != 136) {
					printf("%eDisk error: %d%e", IOresult(DISK_2));
					MIOresume();
					aborted = 1;
					return;
				}
				buffer_idx = 0;
				MIOresume();
				if ( bytes_in_buffer == 0 ) {
					signal_EOT();
					aborted = 0;
					return;
				 }
			}
		}
		putd ( MODEM, C_STX );
		putd ( MODEM, current_block );
		putd ( MODEM, current_block ^ $ff );
		blockwrite ( MODEM, buffer + buffer_idx, packet_size);
		if ( crc_mode ) {
			crc = calculate_crc ( buffer + buffer_idx, packet_size );
			putd ( MODEM, crc >> 8 );
			putd ( MODEM, crc & $ff);
		 }
		else {
			crc = calc_cksum ( buffer + buffer_idx, packet_size );
			putd ( MODEM, crc & $ff );
		}
	}
}



signal_EOT()
{
	byte x;
	printf ("%cEOT..%e", $9c);
	for (x=0; x < 10; ++x) {
		putd (MODEM, C_EOT);
		if ( com_getc (10) == C_ACK )
			break;
	}
}




purge_modem()
{
	do {
	} while (com_getc(1) != C_TIMEOUT);
}




/*------------------------------------------------------*
 *      return either a character from modem,           *
 *      or C_TIMEOUT if "secs" seconds expire.          *
 *------------------------------------------------------*/

com_getc ( byte timeout )
{
	seconds = 0;
	while ( seconds <= timeout ) {
		if (console == 6)
			return ( C_CAN );                                       /* return fake cancel   */
		if (bytes_in())
			return (getd (MODEM));
	}
	return ( C_TIMEOUT );
}



calc_cksum ( char *buffer; int numbytes)
{
#asm {
.ptr:           equ             $a0
		lda             #0
		sta             .crc
		lda             .buffer
		sta             .ptr
		lda             .buffer+1
		sta             .ptr+1
.loop:  ldy             #0
		lda             (.ptr),y
		clc
		adc             .crc
		sta             .crc
.nxtbyte:
		inc             .ptr
		bne             .nv1
		inc             .ptr+1
.nv1:   lda             .numbytes
		sec
		sbc             #1
		sta             .numbytes
		lda             .numbytes+1
		sbc             #0
		sta             .numbytes+1
		ora             .numbytes
		bne             .loop
.done:  lda     .crc
		ldx             #0
		rts
.crc:           ds.b    1
	}
}



calculate_crc ( char *buffer; int numbytes)
{
#asm {
.ptr:           equ             $a0
		lda             #0
		sta             .crc
		sta             .crc+1
		lda             .buffer
		sta             .ptr
		lda             .buffer+1
		sta             .ptr+1
.loop:  ldy             #0
		lda             (.ptr),y
		eor             .crc+1
		tax
		lda             .crc_hitable,x
		eor             .crc
		sta             .crc+1
		lda             .crc_lotable,x
		eor             #0
		sta             .crc
.nxtbyte:
		inc             .ptr
		bne             .nv1
		inc             .ptr+1
.nv1:   lda             .numbytes
		sec
		sbc             #1
		sta             .numbytes
		lda             .numbytes+1
		sbc             #0
		sta             .numbytes+1
		ora             .numbytes
		bne             .loop
.done:  lda     .crc
		ldx             .crc+1
		rts
.crc:           ds.b    2
.crc_lotable:
		dc.b    $00,$21,$42,$63,$84,$A5,$C6,$E7,$08,$29
		dc.b    $4A,$6B,$8C,$AD,$CE,$EF,$31,$10,$73,$52
		dc.b    $B5,$94,$F7,$D6,$39,$18,$7B,$5A,$BD,$9C
		dc.b    $FF,$DE,$62,$43,$20,$01,$E6,$C7,$A4,$85
		dc.b    $6A,$4B,$28,$09,$EE,$CF,$AC,$8D,$53,$72
		dc.b    $11,$30,$D7,$F6,$95,$B4,$5B,$7A,$19,$38
		dc.b    $DF,$FE,$9D,$BC,$C4,$E5,$86,$A7,$40,$61
		dc.b    $02,$23,$CC,$ED,$8E,$AF,$48,$69,$0A,$2B
		dc.b    $F5,$D4,$B7,$96,$71,$50,$33,$12,$FD,$DC
		dc.b    $BF,$9E,$79,$58,$3B,$1A,$A6,$87,$E4,$C5
		dc.b    $22,$03,$60,$41,$AE,$8F,$EC,$CD,$2A,$0B
		dc.b    $68,$49,$97,$B6,$D5,$F4,$13,$32,$51,$70
		dc.b    $9F,$BE,$DD,$FC,$1B,$3A,$59,$78,$88,$A9
		dc.b    $CA,$EB,$0C,$2D,$4E,$6F,$80,$A1,$C2,$E3
		dc.b    $04,$25,$46,$67,$B9,$98,$FB,$DA,$3D,$1C
		dc.b    $7F,$5E,$B1,$90,$F3,$D2,$35,$14,$77,$56
		dc.b    $EA,$CB,$A8,$89,$6E,$4F,$2C,$0D,$E2,$C3
		dc.b    $A0,$81,$66,$47,$24,$05,$DB,$FA,$99,$B8
		dc.b    $5F,$7E,$1D,$3C,$D3,$F2,$91,$B0,$57,$76
		dc.b    $15,$34,$4C,$6D,$0E,$2F,$C8,$E9,$8A,$AB
		dc.b    $44,$65,$06,$27,$C0,$E1,$82,$A3,$7D,$5C
		dc.b    $3F,$1E,$F9,$D8,$BB,$9A,$75,$54,$37,$16
		dc.b    $F1,$D0,$B3,$92,$2E,$0F,$6C,$4D,$AA,$8B
		dc.b    $E8,$C9,$26,$07,$64,$45,$A2,$83,$E0,$C1
		dc.b    $1F,$3E,$5D,$7C,$9B,$BA,$D9,$F8,$17,$36
		dc.b    $55,$74,$93,$B2,$D1,$F0
.crc_hitable:
		dc.b    $00,$10,$20,$30,$40,$50,$60,$70,$81,$91,$A1,$B1,$C1
		dc.b    $D1,$E1,$F1,$12,$02,$32,$22,$52,$42,$72,$62,$93,$83
		dc.b    $B3,$A3,$D3,$C3,$F3,$E3,$24,$34,$04,$14,$64,$74,$44
		dc.b    $54,$A5,$B5,$85,$95,$E5,$F5,$C5,$D5,$36,$26,$16,$06
		dc.b    $76,$66,$56,$46,$B7,$A7,$97,$87,$F7,$E7,$D7,$C7,$48
		dc.b    $58,$68,$78,$08,$18,$28,$38,$C9,$D9,$E9,$F9,$89,$99
		dc.b    $A9,$B9,$5A,$4A,$7A,$6A,$1A,$0A,$3A,$2A,$DB,$CB,$FB
		dc.b    $EB,$9B,$8B,$BB,$AB,$6C,$7C,$4C,$5C,$2C,$3C,$0C,$1C
		dc.b    $ED,$FD,$CD,$DD,$AD,$BD,$8D,$9D,$7E,$6E,$5E,$4E,$3E
		dc.b    $2E,$1E,$0E,$FF,$EF,$DF,$CF,$BF,$AF,$9F,$8F,$91,$81
		dc.b    $B1,$A1,$D1,$C1,$F1,$E1,$10,$00,$30,$20,$50,$40,$70
		dc.b    $60,$83,$93,$A3,$B3,$C3,$D3,$E3,$F3,$02,$12,$22,$32
		dc.b    $42,$52,$62,$72,$B5,$A5,$95,$85,$F5,$E5,$D5,$C5,$34
		dc.b    $24,$14,$04,$74,$64,$54,$44,$A7,$B7,$87,$97,$E7,$F7
		dc.b    $C7,$D7,$26,$36,$06,$16,$66,$76,$46,$56,$D9,$C9,$F9
		dc.b    $E9,$99,$89,$B9,$A9,$58,$48,$78,$68,$18,$08,$38,$28
		dc.b    $CB,$DB,$EB,$FB,$8B,$9B,$AB,$BB,$4A,$5A,$6A,$7A,$0A
		dc.b    $1A,$2A,$3A,$FD,$ED,$DD,$CD,$BD,$AD,$9D,$8D,$7C,$6C
		dc.b    $5C,$4C,$3C,$2C,$1C,$0C,$EF,$FF,$CF,$DF,$AF,$BF,$8F
		dc.b    $9F,$6E,$7E,$4E,$5E,$2E,$3E,$0E,$1E
	}
}