sys/src/cmd/con/xms.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <ctype.h>
   4
   5 enum {
   6         Soh=    0x1,
   7         Stx=    0x2,
   8         Eot=    0x4,
   9         Ack=    0x6,
  10         Nak=    0x15,
  11         Cancel= 0x18,
  12 };
  13
  14 int send(uchar*, int);
  15 int notifyf(void*, char*);
  16
  17 int debug, progress, onek;
  18
  19 void
  20 errorout(int ctl, int bytes)
  21 {
  22         uchar buf[2];
  23
  24         buf[0] = Cancel;
  25         write(1, buf, 1);
  26         fprint(2, "\nxms: gave up after %d bytes\n", bytes);
  27         write(ctl, "rawoff", 6);
  28         exits("cancel");
  29 }
  30
  31 ushort
  32 updcrc(int c, ushort crc)
  33 {
  34         int count;
  35
  36         for (count=8; --count>=0;) {
  37                 if (crc & 0x8000) {
  38                         crc <<= 1;
  39                         crc += (((c<<=1) & 0400)  !=  0);
  40                         crc ^= 0x1021;
  41                 }
  42                 else {
  43                         crc <<= 1;
  44                         crc += (((c<<=1) & 0400)  !=  0);
  45                 }
  46         }
  47         return crc;
  48 }
  49
  50 void
  51 main(int argc, char **argv)
  52 {
  53         uchar c;
  54         uchar buf[1024+5];
  55         uchar seqno;
  56         int fd, ctl;
  57         long n;
  58         int sum;
  59         uchar *p;
  60         int bytes;
  61         int crcmode;
  62
  63         ARGBEGIN{
  64         case 'd':
  65                 debug = 1;
  66                 break;
  67         case 'p':
  68                 progress = 1;
  69                 break;
  70         case '1':
  71                 onek = 1;
  72                 break;
  73         }ARGEND
  74
  75         if(argc != 1){
  76                 fprint(2, "usage: xms filename\n");
  77                 exits("usage");
  78         }
  79         fd = open(argv[0], OREAD);
  80         if(fd < 0){
  81                 perror("xms");
  82                 exits("open");
  83         }
  84
  85         ctl = open("/dev/consctl", OWRITE);
  86         if(ctl < 0){
  87                 perror("xms");
  88                 exits("consctl");
  89         }
  90         write(ctl, "rawon", 5);
  91
  92         /* give the other side a 30 seconds to signal ready */
  93         atnotify(notifyf, 1);
  94         alarm(30*1000);
  95         crcmode = 0;
  96         for(;;){
  97                 if(read(0, &c, 1) != 1){
  98                         fprint(2, "xms: timeout\n");
  99                         exits("timeout");
 100                 }
 101                 c = c & 0x7f;
 102                 if(c == Nak)
 103                         break;
 104                 if(c == 'C') {
 105                         if (debug)
 106                                 fprint(2, "crc mode engaged\n");
 107                         crcmode = 1;
 108                         break;
 109                 }
 110         }
 111         alarm(0);
 112
 113         /* send the file in 128/1024 byte chunks */
 114         for(bytes = 0, seqno = 1; ; bytes += n, seqno++){
 115                 n = read(fd, buf+3, onek ? 1024 : 128);
 116                 if(n < 0)
 117                         exits("read");
 118                 if(n == 0)
 119                         break;
 120                 if(n < (onek ? 1024 : 128))
 121                         memset(&buf[n+3], 0, (onek ? 1024 : 128)-n);
 122                 buf[0] = onek ? Stx : Soh;
 123                 buf[1] = seqno;
 124                 buf[2] = 255 - seqno;
 125
 126                 /* calculate checksum and stuff into last byte */
 127                 if (crcmode) {
 128                         unsigned short crc;
 129                         crc = 0;
 130                         for(p = buf + 3; p < &buf[(onek ? 1024 : 128)+3]; p++)
 131                                 crc = updcrc(*p, crc);
 132                         crc = updcrc(0, crc);
 133                         crc = updcrc(0, crc);
 134                         buf[(onek ? 1024 : 128) + 3] = crc >> 8;
 135                         buf[(onek ? 1024 : 128) + 4] = crc;
 136                 }
 137                 else {
 138                         sum = 0;
 139                         for(p = buf + 3; p < &buf[(onek ? 1024 : 128)+3]; p++)
 140                                 sum += *p;
 141                         buf[(onek ? 1024 : 128) + 3] = sum;
 142                 }
 143
 144                 if(send(buf, (onek ? 1024 : 128) + 4 + crcmode) < 0)
 145                         errorout(ctl, bytes);
 146                 if (progress && bytes % 10240 == 0)
 147                         fprint(2, "%dK\n", bytes / 1024);
 148         }
 149
 150         /* tell other side we're done */
 151         buf[0] = Eot;
 152         if(send(buf, 1) < 0)
 153                 errorout(ctl, bytes);
 154
 155         fprint(2, "xms: %d bytes transmitted\n", bytes);
 156         write(ctl, "rawoff", 6);
 157         exits(0);
 158 }
 159
 160 /*
 161  *  send a message till it's acked or we give up
 162  */
 163 int
 164 send(uchar *buf, int len)
 165 {
 166         int tries;
 167         int n;
 168         uchar c;
 169
 170         for(tries = 0;; tries++, sleep(2*1000)){
 171                 if(tries == 10)
 172                         return -1;
 173                 if(write(1, buf, len) != len)
 174                         return -1;
 175
 176                 alarm(30*1000);
 177                 n = read(0, &c, 1);
 178                 alarm(0);
 179                 if(debug) switch(c){
 180                 case Soh:
 181                         fprint(2, " Soh");
 182                         break;
 183                 case Eot:
 184                         fprint(2, " Eot");
 185                         break;
 186                 case Ack:
 187                         fprint(2, " Ack");
 188                         break;
 189                 case Nak:
 190                         fprint(2, " Nak");
 191                         break;
 192                 case Cancel:
 193                         fprint(2, "\nremote Cancel\n");
 194                         return -1;
 195                 default:
 196                         if(isprint(c))
 197                                 fprint(2, "%c", c);
 198                         else
 199                                 fprint(2, " \\0%o", c);
 200                 }
 201                 c = c & 0x7f;
 202                 if(n == 1 && c == Ack)
 203                         break;
 204         }
 205         return 0;
 206 }
 207
 208 int
 209 notifyf(void *a, char *msg)
 210 {
 211         USED(a);
 212         if(strcmp(msg, "alarm") == 0)
 213                 return 1;
 214         return 0;
 215 }