Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <ctype.h>

enum {
        Soh=    0x1,
        Stx=    0x2,
        Eot=    0x4,
        Ack=    0x6,
        Nak=    0x15,
        Cancel= 0x18,
};

int send(uchar*, int);
int notifyf(void*, char*);

int debug, progress, onek;

void
errorout(int ctl, int bytes)
{
        uchar buf[2];

        buf[0] = Cancel;
        write(1, buf, 1);
        fprint(2, "\nxms: gave up after %d bytes\n", bytes);
        write(ctl, "rawoff", 6);
        exits("cancel");
}

ushort
updcrc(int c, ushort crc)
{
        int count;

        for (count=8; --count>=0;) {
                if (crc & 0x8000) {
                        crc <<= 1;
                        crc += (((c<<=1) & 0400)  !=  0);
                        crc ^= 0x1021;
                }
                else {
                        crc <<= 1;
                        crc += (((c<<=1) & 0400)  !=  0);
                }
        }
        return crc;     
}

void
main(int argc, char **argv)
{
        uchar c;
        uchar buf[1024+5];
        uchar seqno;
        int fd, ctl;
        long n;
        int sum;
        uchar *p;
        int bytes;
        int crcmode;

        ARGBEGIN{
        case 'd':
                debug = 1;
                break;
        case 'p':
                progress = 1;
                break;
        case '1':
                onek = 1;
                break;
        }ARGEND

        if(argc != 1){
                fprint(2, "usage: xms filename\n");
                exits("usage");
        }
        fd = open(argv[0], OREAD);
        if(fd < 0){
                perror("xms");
                exits("open");
        }

        ctl = open("/dev/consctl", OWRITE);
        if(ctl < 0){
                perror("xms");
                exits("consctl");
        }
        write(ctl, "rawon", 5);

        /* give the other side a 30 seconds to signal ready */
        atnotify(notifyf, 1);
        alarm(30*1000);
        crcmode = 0;
        for(;;){
                if(read(0, &c, 1) != 1){
                        fprint(2, "xms: timeout\n");
                        exits("timeout");
                }
                c = c & 0x7f;
                if(c == Nak)
                        break;
                if(c == 'C') {
                        if (debug)
                                fprint(2, "crc mode engaged\n");
                        crcmode = 1;
                        break;
                }
        }
        alarm(0);

        /* send the file in 128/1024 byte chunks */
        for(bytes = 0, seqno = 1; ; bytes += n, seqno++){
                n = read(fd, buf+3, onek ? 1024 : 128);
                if(n < 0)
                        exits("read");
                if(n == 0)
                        break;
                if(n < (onek ? 1024 : 128))
                        memset(&buf[n+3], 0, (onek ? 1024 : 128)-n);
                buf[0] = onek ? Stx : Soh;
                buf[1] = seqno;
                buf[2] = 255 - seqno;

                /* calculate checksum and stuff into last byte */
                if (crcmode) {
                        unsigned short crc;
                        crc = 0;
                        for(p = buf + 3; p < &buf[(onek ? 1024 : 128)+3]; p++)
                                crc = updcrc(*p, crc);
                        crc = updcrc(0, crc);
                        crc = updcrc(0, crc);
                        buf[(onek ? 1024 : 128) + 3] = crc >> 8;
                        buf[(onek ? 1024 : 128) + 4] = crc;
                }
                else {
                        sum = 0;
                        for(p = buf + 3; p < &buf[(onek ? 1024 : 128)+3]; p++)
                                sum += *p;
                        buf[(onek ? 1024 : 128) + 3] = sum;
                }

                if(send(buf, (onek ? 1024 : 128) + 4 + crcmode) < 0)
                        errorout(ctl, bytes);
                if (progress && bytes % 10240 == 0)
                        fprint(2, "%dK\n", bytes / 1024);
        }

        /* tell other side we're done */
        buf[0] = Eot;
        if(send(buf, 1) < 0)
                errorout(ctl, bytes);

        fprint(2, "xms: %d bytes transmitted\n", bytes);
        write(ctl, "rawoff", 6);
        exits(0);
}

/*
 *  send a message till it's acked or we give up
 */
int
send(uchar *buf, int len)
{
        int tries;
        int n;
        uchar c;

        for(tries = 0;; tries++, sleep(2*1000)){
                if(tries == 10)
                        return -1;
                if(write(1, buf, len) != len)
                        return -1;
                
                alarm(30*1000);
                n = read(0, &c, 1);
                alarm(0);
                if(debug) switch(c){
                case Soh:
                        fprint(2, " Soh");
                        break;
                case Eot:
                        fprint(2, " Eot");
                        break;
                case Ack:
                        fprint(2, " Ack");
                        break;
                case Nak:
                        fprint(2, " Nak");
                        break;
                case Cancel:
                        fprint(2, "\nremote Cancel\n");
                        return -1;
                default:
                        if(isprint(c))
                                fprint(2, "%c", c);
                        else
                                fprint(2, " \\0%o", c);
                }
                c = c & 0x7f;
                if(n == 1 && c == Ack)
                        break;
        }
        return 0;
}

int
notifyf(void *a, char *msg)
{
        USED(a);
        if(strcmp(msg, "alarm") == 0)
                return 1;
        return 0;
}