DLOAD.C
/* DLOAD 16 Jan 88 Burt Mitchell */
/* */
/* Host software for an PC compatible to send files to a */
/* Color Computer using the DLOAD command. */
/* The Coco must be running Extended Color Basic v1.1 or OLDER */
/* This program uses 1200 baud as it is the default for the Coco. It is */
/* configured to use the PC's com1: port. To change this you will have to */
/* edit the procedures transmit_char() and receive_char(). */
/* This program has not been tested in the DLOADM mode as I have no way */
/* of getting a Coco machine language routine into the PC in the first */
/* place. */
/* To operate DLOAD: */
/* on the PC enter DLOAD filename.ext a */
/* the PC will inform you that it is waiting. */
/* on the Coco enter DLOAD */
/* Modified for use with unix by Bryan Clingman (bac@realtimeweb.com) */
/* 3-Jun-1997 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#define true 1
#define false 0
#define ok 1
#define bad 0
/* literals for the DLOAD protocol */
#define file_req 0x8A
#define block_req 0x97
#define NAK 0xDE
#define ACK 0xC8
#define EOT 0xBC
#define ABORT 0xBC
#define ASCII 0xFF
#define BINARY 0x00
#define BASIC 0x00
#define ML 0x02
#define block_size 127
unsigned char chksum,
file_type,
asc_flag,
proceed;
unsigned char rx_char;
char *tx_name;
char *port;
FILE *infile;
FILE *fp;
int tx_delay;
void transmit_char(unsigned char tx_char)
{
fputc(tx_char, fp);
#ifdef DEBUG
fprintf(stderr, " [%02X]", tx_char);
#endif
usleep(tx_delay);
}
void receive_char()
{
rx_char = fgetc(fp);
#ifdef DEBUG
if (rx_char != 0xFF && rx_char != 0)
fprintf(stderr, " %02X", rx_char);
#endif
if (rx_char == ABORT)
{
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
fprintf(stderr, "transfer aborted by target.\n");
exit(1);
}
}
void initiate_transfer()
{
chksum = (file_type ^ asc_flag);
transmit_char(ACK);
transmit_char(file_type);
transmit_char(asc_flag);
transmit_char(chksum);
}
char rcv_file_name(char *filename)
{
int count;
char sum;
char status;
filename[8] = 0;
count = 0;
while (count <= 7)
{
receive_char();
filename[count] = rx_char;
chksum = (chksum ^ rx_char);
++count;
}
receive_char();
sum = rx_char;
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
fprintf(stderr, "target requested \"%s\"\n", filename);
if (sum != chksum)
{
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
fprintf(stderr, "filename checksum bad.\n");
status = bad;
filename[0] = '\0';
}
else
status = ok;
return status;
}
void send_file()
{
int count,
j;
char tx_flag,
xfer_done,
first_time,
send_new_block;
unsigned char file_char[130],
xfer_length,
sum,
block_num,
old_block_num;
long int total_xfer;
/**/
first_time = true;
total_xfer = 0;
xfer_length = 0;
xfer_done = false;
tx_flag = true;
while (tx_flag == true)
{
send_new_block = true;
while (rx_char != block_req)
receive_char();
transmit_char(block_req);
chksum = 0;
/* get the MSByte of the block number */
receive_char();
chksum = (chksum ^ rx_char);
block_num = (rx_char << 7);
/* get the LSByte of the block number */
receive_char();
chksum = (chksum ^ rx_char);
block_num = (rx_char | block_num);
#ifdef DEBUG
fprintf(stderr, "\nRequested block # %i\n", block_num);
#endif
/* should we retransmit the previous block? */
if (first_time == false)
if (block_num == old_block_num)
send_new_block = false;
/* Get the checksum for the block number being requested. */
/* Does it match our calculation? */
receive_char();
sum = rx_char;
if (sum == chksum)
{
transmit_char(ACK);
first_time = false;
if (xfer_done == true)
{
/* Send a block with a length of 0 and 128 bytes of */
/* anything along with a checksum for the block. */
/* This tells the Coco that the file is ended. */
tx_flag = false;
xfer_length = 0;
j = 0;
while (j <= block_size)
{
file_char[j] = 0;
++j;
}
}
else
{
/* go ahead and read in another 128 bytes. */
/* If there aren't 128 bytes available pad the data */
/* to 128 bytes. The checksum must still be correct. */
if (send_new_block == true)
{
count = 0;
while (count <= block_size)
{
file_char[count] = getc(infile);
/* The Coco can't handle linefeeds */
if (asc_flag == ASCII)
if (file_char[count] == '\n')
file_char[count] = '\r';
xfer_length = (count + 1);
++count;
if (feof(infile))
{
xfer_done = true;
while (count <= block_size)
{
file_char[count] = 0;
++count;
if (asc_flag != ASCII)
tx_flag = false;
}
}
}
}
else
{
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
fprintf(stderr, "Re-transmitting block #%d\n", block_num);
}
}
/* transmit whatever is in the buffer */
transmit_char(xfer_length);
chksum = 0;
chksum = (chksum ^ xfer_length);
count = 0;
while (count <= block_size)
{
transmit_char(file_char[count]);
chksum = (chksum ^ file_char[count]);
++count;
}
transmit_char(chksum);
total_xfer = (total_xfer + xfer_length);
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
fprintf(stderr, "Total transmitted = %ld\r", total_xfer);
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
old_block_num = block_num;
}
else
{
fprintf(stderr, "checksum mismatch\n");
transmit_char(NAK);
}
}
fprintf(stderr, "\n");
}
void xfer_abort()
{
transmit_char(NAK);
#ifdef DEBUG
fprintf(stderr, "\n");
#endif
fprintf(stderr, "transfer aborted by host\n");
exit(1);
}
void init_port()
{
fp = fopen(port,"a+");
if (!fp)
fprintf(stderr, "Error opening port\n");
setvbuf(fp, NULL, _IONBF, 0);
}
int main(int argc, char *argv[])
{
char filename[9];
char status;
if (argc < 4)
{
fprintf(stderr, "usage: DLOAD [filename.ext] [A or B] [port]\n");
exit(1);
}
tx_name = argv[1];
if ((*argv[2] == 'B') || (*argv[2] == 'b'))
{
file_type = ML;
asc_flag = BINARY;
infile = fopen(tx_name,"rb");
}
else
if ((*argv[2] == 'A') || (*argv[2] == 'a'))
{
file_type = BASIC;
asc_flag = ASCII;
infile = fopen(tx_name,"r");
}
else
{
fprintf(stderr, "unknown file type\n");
exit(1);
}
if (infile == NULL)
{
fprintf(stderr, "cant open the file to be transmitted\n");
exit(1);
}
if (argc > 4)
tx_delay = atoi(argv[4]);
else
tx_delay = 0;
port = argv[3];
init_port();
/* wait for the coco to start the transfer */
while (rx_char != file_req)
receive_char();
proceed = true;
/* proceed with the file transfer */
while (proceed == true)
{
/* get the file name from the coco. We arent using it but */
/* it's part of the protocol. */
transmit_char(file_req);
status = rcv_file_name(filename);
/* if non-empty file name, switch file */
if (status == ok && strcmp(filename, " "))
{
int lastc;
/* zero out trailing spaces */
for (lastc = 7; lastc > 0; lastc--)
{
if (filename[lastc] == ' ')
filename[lastc] = '\0';
else
break;
}
fprintf(stderr, "trimmed to \"%s\"\n", filename);
fclose(infile);
/* only binary supported for now */
infile = fopen(filename,"rb");
if (infile == NULL)
{
fprintf(stderr, "cannot open %s\n", filename);
/* abort and wait for new request */
/* FIXME Dragon does not interpret NAK here */
transmit_char(NAK);
while (rx_char != file_req)
receive_char();
infile = fopen(tx_name, "rb");
continue;
}
}
/* tell the coco about the file it will receive. */
initiate_transfer();
/* now send the file */
send_file();
if (status == ok)
{
proceed = false;
}
else
{
proceed = false;
fprintf(stderr, "file not transmitted successfully\n");
}
}
return 0;
}
RTS
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