Commit | Line | Data |
---|---|---|
b0b08d43 | 1 | #ifndef lint |
0f4556f1 | 2 | static char sccsid[] = "@(#)pk0.c 5.1 (Berkeley) 7/2/83"; |
b0b08d43 SL |
3 | #endif |
4 | ||
5 | extern char *malloc(); | |
6 | ||
7 | #define USER 1 | |
8 | #include <stdio.h> | |
9 | #ifdef SYSIII | |
10 | #include <sys/types.h> | |
11 | #endif | |
12 | #include "pk.p" | |
13 | #include <sys/param.h> | |
14 | #include "pk.h" | |
15 | #include <sys/buf.h> | |
16 | ||
17 | ||
18 | /* | |
19 | * packet driver | |
20 | */ | |
21 | ||
22 | char next[8] ={ 1,2,3,4,5,6,7,0}; /* packet sequence numbers */ | |
23 | char mask[8] ={ 1,2,4,010,020,040,0100,0200 }; | |
24 | ||
25 | struct pack *pklines[NPLINES]; | |
26 | ||
27 | /* | |
28 | * Here are a couple of strange variables (rti!trt). | |
29 | * pkactive is only incremented in pkopen. | |
30 | * perhaps it should be decremented in pkclose? | |
31 | * And pkdebug is set in gio.c but never used. | |
32 | */ | |
33 | int pkactive; | |
34 | int pkdebug; | |
35 | ||
36 | /* | |
37 | * receive control messages | |
38 | */ | |
39 | pkcntl(c, pk) | |
40 | register struct pack *pk; | |
41 | { | |
42 | register cntl, val; | |
43 | ||
44 | val = c & MOD8; | |
45 | cntl = (c>>3) & MOD8; | |
46 | ||
47 | if ( ! ISCNTL(c) ) { | |
48 | fprintf(stderr, "not cntl\n"); | |
49 | return; | |
50 | } | |
51 | ||
52 | if (pk->p_mode & 02) | |
53 | fprintf(stderr, "%o ",c); | |
54 | switch(cntl) { | |
55 | ||
56 | case INITB: | |
57 | val++; | |
58 | pk->p_xsize = pksizes[val]; | |
59 | pk->p_lpsize = val; | |
60 | pk->p_bits = DTOM(pk->p_xsize); | |
61 | if (pk->p_state & LIVE) { | |
62 | pk->p_msg |= M_INITC; | |
63 | break; | |
64 | } | |
65 | pk->p_state |= INITb; | |
66 | if ((pk->p_state & INITa)==0) { | |
67 | break; | |
68 | } | |
69 | pk->p_rmsg &= ~M_INITA; | |
70 | pk->p_msg |= M_INITC; | |
71 | break; | |
72 | ||
73 | case INITC: | |
74 | if ((pk->p_state&INITab)==INITab) { | |
75 | pk->p_state = LIVE; | |
76 | WAKEUP(&pk->p_state); | |
77 | pk->p_rmsg &= ~M_INITB; | |
78 | } else | |
79 | pk->p_msg |= M_INITB; | |
80 | if (val) | |
81 | pk->p_swindow = val; | |
82 | break; | |
83 | case INITA: | |
84 | if (val==0 && pk->p_state&LIVE) { | |
85 | fprintf(stderr, "alloc change not implemented\n"); | |
86 | break; | |
87 | } | |
88 | if (val) { | |
89 | pk->p_state |= INITa; | |
90 | pk->p_msg |= M_INITB; | |
91 | pk->p_rmsg |= M_INITB; | |
92 | pk->p_swindow = val; | |
93 | } | |
94 | break; | |
95 | case RJ: | |
96 | pk->p_state |= RXMIT; | |
97 | pk->p_msg |= M_RR; | |
98 | case RR: | |
99 | pk->p_rpr = val; | |
100 | if (pksack(pk)==0) { | |
101 | WAKEUP(&pk->p_ps); | |
102 | } | |
103 | break; | |
104 | case SRJ: | |
105 | fprintf(stderr, "srj not implemented\n"); | |
106 | break; | |
107 | case CLOSE: | |
108 | pk->p_state = DOWN+RCLOSE; | |
109 | SIGNAL; | |
110 | WAKEUP(&pk->p_pr); | |
111 | WAKEUP(&pk->p_ps); | |
112 | WAKEUP(&pk->p_state); | |
113 | return; | |
114 | } | |
115 | out: | |
116 | if (pk->p_msg) | |
117 | pkoutput(pk); | |
118 | } | |
119 | ||
120 | ||
121 | ||
122 | pkaccept(pk) | |
123 | register struct pack *pk; | |
124 | { | |
125 | register x,seq; | |
126 | char m, cntl, *p, imask, **bp; | |
127 | int bad,accept,skip,s,t,h,cc; | |
128 | unsigned short sum; | |
129 | ||
130 | ||
131 | bad = accept = skip = 0; | |
132 | /* | |
133 | * wait for input | |
134 | */ | |
135 | LOCK; | |
136 | x = next[pk->p_pr]; | |
137 | while ((imask=pk->p_imap) == 0 && pk->p_rcount==0) { | |
138 | PKGETPKT(pk); | |
139 | SLEEP(&pk->p_pr, PKIPRI); | |
140 | } | |
141 | pk->p_imap = 0; | |
142 | UNLOCK; | |
143 | ||
144 | ||
145 | /* | |
146 | * determine input window in m. | |
147 | */ | |
148 | t = (~(-1<<(int)(pk->p_rwindow))) <<x; | |
149 | m = t; | |
150 | m |= t>>8; | |
151 | ||
152 | ||
153 | /* | |
154 | * mark newly accepted input buffers | |
155 | */ | |
156 | for(x=0; x<8; x++) { | |
157 | ||
158 | if ((imask & mask[x]) == 0) | |
159 | continue; | |
160 | ||
161 | if (((cntl=pk->p_is[x])&0200)==0) { | |
162 | bad++; | |
163 | free: | |
164 | bp = (char **)pk->p_ib[x]; | |
165 | LOCK; | |
166 | *bp = (char *)pk->p_ipool; | |
167 | pk->p_ipool = bp; | |
168 | pk->p_is[x] = 0; | |
169 | UNLOCK; | |
170 | continue; | |
171 | } | |
172 | ||
173 | pk->p_is[x] = ~(B_COPY+B_MARK); | |
174 | sum = (unsigned)chksum(pk->p_ib[x], pk->p_rsize) ^ (unsigned)(cntl&0377); | |
175 | sum += pk->p_isum[x]; | |
176 | if (sum == CHECK) { | |
177 | seq = (cntl>>3) & MOD8; | |
178 | if (m & mask[seq]) { | |
179 | if (pk->p_is[seq] & (B_COPY | B_MARK)) { | |
180 | dup: | |
181 | pk->p_msg |= M_RR; | |
182 | skip++; | |
183 | goto free; | |
184 | } | |
185 | if (x != seq) { | |
186 | LOCK; | |
187 | p = pk->p_ib[x]; | |
188 | pk->p_ib[x] = pk->p_ib[seq]; | |
189 | pk->p_is[x] = pk->p_is[seq]; | |
190 | pk->p_ib[seq] = p; | |
191 | UNLOCK; | |
192 | } | |
193 | pk->p_is[seq] = B_MARK; | |
194 | accept++; | |
195 | cc = 0; | |
196 | if (cntl&B_SHORT) { | |
197 | pk->p_is[seq] = B_MARK+B_SHORT; | |
198 | p = pk->p_ib[seq]; | |
199 | cc = (unsigned)*p++ & 0377; | |
200 | if (cc & 0200) { | |
201 | cc &= 0177; | |
202 | cc |= *p << 7; | |
203 | } | |
204 | } | |
205 | pk->p_isum[seq] = pk->p_rsize - cc; | |
206 | } else { | |
207 | goto dup; | |
208 | } | |
209 | } else { | |
210 | bad++; | |
211 | goto free; | |
212 | } | |
213 | } | |
214 | ||
215 | /* | |
216 | * scan window again turning marked buffers into | |
217 | * COPY buffers and looking for missing sequence | |
218 | * numbers. | |
219 | */ | |
220 | accept = 0; | |
221 | for(x=next[pk->p_pr],t=h= -1; m & mask[x]; x = next[x]) { | |
222 | if (pk->p_is[x] & B_MARK) | |
223 | pk->p_is[x] |= B_COPY; | |
224 | /* hole code | |
225 | if (pk->p_is[x] & B_COPY) { | |
226 | if (h<0 && t>=0) | |
227 | h = x; | |
228 | } else { | |
229 | if (t<0) | |
230 | t = x; | |
231 | } | |
232 | */ | |
233 | if (pk->p_is[x] & B_COPY) { | |
234 | if (t >= 0) { | |
235 | bp = (char **)pk->p_ib[x]; | |
236 | LOCK; | |
237 | *bp = (char *)pk->p_ipool; | |
238 | pk->p_ipool = bp; | |
239 | pk->p_is[x] = 0; | |
240 | UNLOCK; | |
241 | skip++; | |
242 | } else | |
243 | accept++; | |
244 | } else { | |
245 | if (t<0) | |
246 | t = x; | |
247 | } | |
248 | } | |
249 | ||
250 | if (bad) { | |
251 | pk->p_msg |= M_RJ; | |
252 | } | |
253 | ||
254 | if (skip) { | |
255 | pk->p_msg |= M_RR; | |
256 | } | |
257 | ||
258 | pk->p_rcount = accept; | |
259 | return(accept); | |
260 | } | |
261 | ||
262 | ||
263 | pkread(S) | |
264 | SDEF; | |
265 | { | |
266 | register struct pack *pk; | |
267 | register x,s; | |
268 | int is,cc,xfr,count; | |
269 | char *cp, **bp; | |
270 | ||
271 | pk = PADDR; | |
272 | xfr = 0; | |
273 | count = 0; | |
274 | while (pkaccept(pk)==0); | |
275 | ||
276 | ||
277 | while (UCOUNT) { | |
278 | ||
279 | x = next[pk->p_pr]; | |
280 | is = pk->p_is[x]; | |
281 | ||
282 | if (is & B_COPY) { | |
283 | cc = MIN(pk->p_isum[x], UCOUNT); | |
284 | if (cc==0 && xfr) { | |
285 | break; | |
286 | } | |
287 | if (is & B_RESID) | |
288 | cp = pk->p_rptr; | |
289 | else { | |
290 | cp = pk->p_ib[x]; | |
291 | if (is & B_SHORT) { | |
292 | if (*cp++ & 0200) | |
293 | cp++; | |
294 | } | |
295 | } | |
296 | IOMOVE(cp,cc,B_READ); | |
297 | count += cc; | |
298 | xfr++; | |
299 | pk->p_isum[x] -= cc; | |
300 | if (pk->p_isum[x] == 0) { | |
301 | pk->p_pr = x; | |
302 | bp = (char **)pk->p_ib[x]; | |
303 | LOCK; | |
304 | *bp = (char *)pk->p_ipool; | |
305 | pk->p_ipool = bp; | |
306 | pk->p_is[x] = 0; | |
307 | pk->p_rcount--; | |
308 | UNLOCK; | |
309 | pk->p_msg |= M_RR; | |
310 | } else { | |
311 | pk->p_rptr = cp+cc; | |
312 | pk->p_is[x] |= B_RESID; | |
313 | } | |
314 | if (cc==0) | |
315 | break; | |
316 | } else | |
317 | break; | |
318 | } | |
319 | pkoutput(pk); | |
320 | return(count); | |
321 | } | |
322 | ||
323 | ||
324 | ||
325 | ||
326 | pkwrite(S) | |
327 | SDEF; | |
328 | { | |
329 | register struct pack *pk; | |
330 | register x; | |
331 | int partial; | |
332 | caddr_t cp; | |
333 | int cc, s, fc, count; | |
334 | ||
335 | pk = PADDR; | |
336 | if (pk->p_state&DOWN || !pk->p_state&LIVE) { | |
337 | SETERROR; | |
338 | return(-1); | |
339 | } | |
340 | ||
341 | count = UCOUNT; | |
342 | do { | |
343 | LOCK; | |
344 | while (pk->p_xcount>=pk->p_swindow) { | |
345 | pkoutput(pk); | |
346 | PKGETPKT(pk); | |
347 | SLEEP(&pk->p_ps,PKOPRI); | |
348 | } | |
349 | x = next[pk->p_pscopy]; | |
350 | while (pk->p_os[x]!=B_NULL) { | |
351 | PKGETPKT(pk); | |
352 | SLEEP(&pk->p_ps,PKOPRI); | |
353 | } | |
354 | pk->p_os[x] = B_MARK; | |
355 | pk->p_pscopy = x; | |
356 | pk->p_xcount++; | |
357 | UNLOCK; | |
358 | ||
359 | cp = pk->p_ob[x] = GETEPACK; | |
360 | partial = 0; | |
361 | if ((int)UCOUNT < pk->p_xsize) { | |
362 | cc = UCOUNT; | |
363 | fc = pk->p_xsize - cc; | |
364 | *cp = fc&0177; | |
365 | if (fc > 127) { | |
366 | *cp++ |= 0200; | |
367 | *cp++ = fc>>7; | |
368 | } else | |
369 | cp++; | |
370 | partial = B_SHORT; | |
371 | } else | |
372 | cc = pk->p_xsize; | |
373 | IOMOVE(cp,cc,B_WRITE); | |
374 | pk->p_osum[x] = chksum(pk->p_ob[x], pk->p_xsize); | |
375 | pk->p_os[x] = B_READY+partial; | |
376 | pkoutput(pk); | |
377 | } while (UCOUNT); | |
378 | ||
379 | return(count); | |
380 | } | |
381 | ||
382 | pksack(pk) | |
383 | register struct pack *pk; | |
384 | { | |
385 | register x, i; | |
386 | ||
387 | i = 0; | |
388 | for(x=pk->p_ps; x!=pk->p_rpr; ) { | |
389 | x = next[x]; | |
390 | if (pk->p_os[x]&B_SENT) { | |
391 | i++; | |
392 | pk->p_os[x] = B_NULL; | |
393 | pk->p_state &= ~WAITO; | |
394 | pk->p_xcount--; | |
395 | FREEPACK(pk->p_ob[x], pk->p_bits); | |
396 | pk->p_ps = x; | |
397 | WAKEUP(&pk->p_ps); | |
398 | } | |
399 | } | |
400 | return(i); | |
401 | } | |
402 | ||
403 | ||
404 | ||
405 | pkoutput(pk) | |
406 | register struct pack *pk; | |
407 | { | |
408 | register x,rx; | |
409 | int s; | |
410 | char bstate; | |
411 | int i; | |
412 | SDEF; | |
413 | int flag; | |
414 | ||
415 | flag = 0; | |
416 | ISYSTEM; | |
417 | LOCK; | |
418 | if (pk->p_obusy++ || OBUSY) { | |
419 | pk->p_obusy--; | |
420 | UNLOCK; | |
421 | return; | |
422 | } | |
423 | UNLOCK; | |
424 | ||
425 | ||
426 | /* | |
427 | * find seq number and buffer state | |
428 | * of next output packet | |
429 | */ | |
430 | if (pk->p_state&RXMIT) { | |
431 | pk->p_nxtps = next[pk->p_rpr]; | |
432 | flag++; | |
433 | } | |
434 | x = pk->p_nxtps; | |
435 | bstate = pk->p_os[x]; | |
436 | ||
437 | ||
438 | /* | |
439 | * Send control packet if indicated | |
440 | */ | |
441 | if (pk->p_msg) { | |
442 | if (pk->p_msg & ~M_RR || !(bstate&B_READY) ) { | |
443 | x = pk->p_msg; | |
444 | for(i=0; i<8; i++) | |
445 | if (x&1) | |
446 | break; else | |
447 | x >>= 1; | |
448 | x = i; | |
449 | x <<= 3; | |
450 | switch(i) { | |
451 | case CLOSE: | |
452 | break; | |
453 | case RJ: | |
454 | case RR: | |
455 | x += pk->p_pr; | |
456 | break; | |
457 | case SRJ: | |
458 | break; | |
459 | case INITB: | |
460 | x += pksize(pk->p_rsize); | |
461 | break; | |
462 | case INITC: | |
463 | x += pk->p_rwindow; | |
464 | break; | |
465 | case INITA: | |
466 | x += pk->p_rwindow; | |
467 | break; | |
468 | } | |
469 | ||
470 | pk->p_msg &= ~mask[i]; | |
471 | pkxstart(pk, x, -1); | |
472 | goto out; | |
473 | } | |
474 | } | |
475 | ||
476 | ||
477 | /* | |
478 | * Don't send data packets if line is marked dead. | |
479 | */ | |
480 | if (pk->p_state&DOWN) { | |
481 | WAKEUP(&pk->p_ps); | |
482 | goto out; | |
483 | } | |
484 | /* | |
485 | * Start transmission (or retransmission) of data packets. | |
486 | */ | |
487 | if (bstate & (B_READY|B_SENT)) { | |
488 | char seq; | |
489 | ||
490 | bstate |= B_SENT; | |
491 | seq = x; | |
492 | pk->p_nxtps = next[x]; | |
493 | ||
494 | x = 0200+pk->p_pr+(seq<<3); | |
495 | if (bstate & B_SHORT) | |
496 | x |= 0100; | |
497 | pkxstart(pk, x, seq); | |
498 | pk->p_os[seq] = bstate; | |
499 | pk->p_state &= ~RXMIT; | |
500 | pk->p_nout++; | |
501 | goto out; | |
502 | } | |
503 | /* | |
504 | * enable timeout if there's nothing to send | |
505 | * and transmission buffers are languishing | |
506 | */ | |
507 | if (pk->p_xcount) { | |
508 | pk->p_timer = 2; | |
509 | pk->p_state |= WAITO; | |
510 | } else | |
511 | pk->p_state &= ~WAITO; | |
512 | WAKEUP(&pk->p_ps); | |
513 | out: | |
514 | pk->p_obusy = 0; | |
515 | } | |
516 | ||
517 | ||
518 | /* | |
519 | * shut down line by | |
520 | * ignoring new input | |
521 | * letting output drain | |
522 | * releasing space and turning off line discipline | |
523 | */ | |
524 | pkclose(S) | |
525 | SDEF; | |
526 | { | |
527 | register struct pack *pk; | |
528 | register i,s,rbits; | |
529 | char **bp; | |
530 | int rcheck; | |
531 | char *p; | |
532 | ||
533 | ||
534 | pk = PADDR; | |
535 | pk->p_state |= DRAINO; | |
536 | ||
537 | ||
538 | /* | |
539 | * try to flush output | |
540 | */ | |
541 | i = 0; | |
542 | LOCK; | |
543 | pk->p_timer = 2; | |
544 | while (pk->p_xcount && pk->p_state&LIVE) { | |
545 | if (pk->p_state&(RCLOSE+DOWN) || ++i > 2) | |
546 | break; | |
547 | pkoutput(pk); | |
548 | SLEEP(&pk->p_ps,PKOPRI); | |
549 | } | |
550 | pk->p_timer = 0; | |
551 | pk->p_state |= DOWN; | |
552 | UNLOCK; | |
553 | ||
554 | ||
555 | /* | |
556 | * try to exchange CLOSE messages | |
557 | */ | |
558 | i = 0; | |
559 | while ((pk->p_state&RCLOSE)==0 && i<2) { | |
560 | pk->p_msg = M_CLOSE; | |
561 | pk->p_timer = 2; | |
562 | pkoutput(pk); | |
563 | SLEEP(&pk->p_ps, PKOPRI); | |
564 | i++; | |
565 | } | |
566 | ||
567 | ||
568 | for(i=0;i<NPLINES;i++) | |
569 | if (pklines[i]==pk) { | |
570 | pklines[i] = NULL; | |
571 | } | |
572 | TURNOFF; | |
573 | ||
574 | ||
575 | /* | |
576 | * free space | |
577 | */ | |
578 | rbits = DTOM(pk->p_rsize); | |
579 | rcheck = 0; | |
580 | for (i=0;i<8;i++) { | |
581 | if (pk->p_os[i]!=B_NULL) { | |
582 | FREEPACK(pk->p_ob[i],pk->p_bits); | |
583 | pk->p_xcount--; | |
584 | } | |
585 | if (pk->p_is[i]!=B_NULL) { | |
586 | FREEPACK(pk->p_ib[i],rbits); | |
587 | rcheck++; | |
588 | } | |
589 | } | |
590 | LOCK; | |
591 | while (pk->p_ipool != NULL) { | |
592 | bp = pk->p_ipool; | |
593 | pk->p_ipool = (char **)*bp; | |
594 | rcheck++; | |
595 | FREEPACK(bp, rbits); | |
596 | } | |
597 | UNLOCK; | |
598 | if (rcheck != pk->p_rwindow) { | |
599 | fprintf(stderr, "r short %d want %d\n",rcheck,pk->p_rwindow); | |
600 | fprintf(stderr, "rcount = %d\n",pk->p_rcount); | |
601 | fprintf(stderr, "xcount = %d\n",pk->p_xcount); | |
602 | } | |
603 | FREEPACK((caddr_t)pk, npbits); | |
604 | } | |
605 | ||
606 | ||
607 | ||
608 | pkreset(pk) | |
609 | register struct pack *pk; | |
610 | { | |
611 | ||
612 | pk->p_ps = pk->p_pr = pk->p_rpr = 0; | |
613 | pk->p_nxtps = 1; | |
614 | } | |
615 | ||
616 | chksum(s,n) | |
617 | register char *s; | |
618 | register n; | |
619 | { | |
620 | register unsigned sum, t; | |
621 | register x; | |
622 | ||
623 | sum = -1; | |
624 | x = 0; | |
625 | ||
626 | do { | |
627 | if (sum&0x8000) { | |
628 | sum <<= 1; | |
629 | sum++; | |
630 | } else | |
631 | sum <<= 1; | |
632 | t = sum; | |
633 | sum += (unsigned)*s++ & 0377; | |
634 | x += sum^n; | |
635 | if ((sum&0xffff) <= (t&0xffff)) { | |
636 | sum ^= x; | |
637 | } | |
638 | } while (--n > 0); | |
639 | ||
640 | return(sum & 0xffff); | |
641 | } | |
642 | ||
643 | pkline(pk) | |
644 | register struct pack *pk; | |
645 | { | |
646 | register i; | |
647 | for(i=0;i<NPLINES;i++) { | |
648 | if (pklines[i]==pk) | |
649 | return(i); | |
650 | } | |
651 | return(-i); | |
652 | } | |
653 | ||
654 | pkzero(s,n) | |
655 | register char *s; | |
656 | register n; | |
657 | { | |
658 | while (n--) | |
659 | *s++ = 0; | |
660 | } | |
661 | ||
662 | pksize(n) | |
663 | register n; | |
664 | { | |
665 | register k; | |
666 | ||
667 | n >>= 5; | |
668 | for(k=0; n >>= 1; k++); | |
669 | return(k); | |
670 | } |