Commit | Line | Data |
---|---|---|
7537529b KS |
1 | # |
2 | ||
3 | /* | |
4 | * Mail -- a program for sending and receiving mail. | |
5 | * | |
6 | * Network name modification routines. | |
7 | */ | |
8 | ||
9 | #include "rcv.h" | |
10 | #include <ctype.h> | |
11 | ||
12 | static char *SccsId = "@(#)optim.c 1.1 %G%"; | |
13 | ||
14 | /* | |
15 | * Map a name into the correct network "view" of the | |
16 | * name. This is done by prepending the name with the | |
17 | * network address of the sender, then optimizing away | |
18 | * nonsense. | |
19 | */ | |
20 | ||
21 | char *metanet = "!^:%@."; | |
22 | ||
23 | char * | |
24 | netmap(name, from) | |
25 | char name[], from[]; | |
26 | { | |
27 | char nbuf[BUFSIZ], ret[BUFSIZ]; | |
28 | register char *cp; | |
29 | ||
30 | if (strlen(from) == 0) | |
31 | return(name); | |
32 | if (any('@', name) || any('%', name)) | |
33 | return(arpafix(name, from)); | |
34 | cp = revarpa(from); | |
35 | if (cp == NOSTR) | |
36 | return(name); | |
37 | strcpy(nbuf, cp); | |
38 | cp = &nbuf[strlen(nbuf) - 1]; | |
39 | while (!any(*cp, metanet) && cp > nbuf) | |
40 | cp--; | |
41 | if (cp == nbuf) | |
42 | return(name); | |
43 | *++cp = 0; | |
44 | strcat(nbuf, revarpa(name)); | |
45 | optim(nbuf, ret); | |
46 | cp = revarpa(ret); | |
47 | if (!icequal(name, cp)) | |
48 | return((char *) savestr(cp)); | |
49 | return(name); | |
50 | } | |
51 | ||
52 | /* | |
53 | * Rename the given network path to use | |
54 | * the kinds of names that we would right here. | |
55 | */ | |
56 | ||
57 | char * | |
58 | rename(str) | |
59 | char str[]; | |
60 | { | |
61 | register char *cp, *cp2; | |
62 | char buf[BUFSIZ], path[BUFSIZ]; | |
63 | register int c, host; | |
64 | ||
65 | strcpy(path, ""); | |
66 | for (;;) { | |
67 | if ((c = *cp++) == 0) | |
68 | break; | |
69 | cp2 = buf; | |
70 | while (!any(c, metanet) && c != 0) { | |
71 | *cp2++ = c; | |
72 | c = *cp++; | |
73 | } | |
74 | *cp2 = 0; | |
75 | if (c == 0) { | |
76 | strcat(path, buf); | |
77 | break; | |
78 | } | |
79 | host = netlook(buf, ntype(c)); | |
80 | strcat(path, netname(host)); | |
81 | stradd(path, c); | |
82 | } | |
83 | if (strcmp(str, path) != 0) | |
84 | return(savestr(path)); | |
85 | return(str); | |
86 | } | |
87 | /* | |
88 | * Turn a network machine name into a unique character | |
89 | * + give connection-to status. BN -- connected to Bell Net. | |
90 | * AN -- connected to ARPA net, SN -- connected to Schmidt net. | |
91 | * CN -- connected to COCANET. | |
92 | */ | |
93 | ||
94 | #define AN 1 /* Connected to ARPA net */ | |
95 | #define BN 2 /* Connected to BTL net */ | |
96 | #define CN 4 /* Connected to COCANET */ | |
97 | #define SN 8 /* Connected to Schmidt net */ | |
98 | ||
99 | struct netmach { | |
100 | char *nt_machine; | |
101 | char nt_mid; | |
102 | short nt_type; | |
103 | } netmach[] = { | |
104 | "a", 'a', SN, | |
105 | "b", 'b', SN, | |
106 | "c", 'c', SN, | |
107 | "d", 'd', SN, | |
108 | "e", 'e', SN, | |
109 | "f", 'f', SN, | |
110 | "g", 'g', SN, | |
111 | "ingres", 'i', AN|SN, | |
112 | "ing70", 'i', AN|SN, | |
113 | "berkeley", 'i', AN|SN, | |
114 | "ingvax", 'j', SN, | |
115 | "virus", 'k', SN, | |
116 | "vlsi", 'l', SN, | |
117 | "image", 'm', SN, | |
118 | "esvax", 'o', SN, | |
119 | "sesm", 'o', SN, | |
120 | "q", 'q', SN, | |
121 | "research", 'R', BN, | |
122 | "arpavax", 'r', SN, | |
123 | "src", 's', SN, | |
124 | "mathstat", 't', SN, | |
125 | "csvax", 'v', BN|SN, | |
126 | "vax", 'v', BN|SN, | |
127 | "ucb", 'v', BN|SN, | |
128 | "ucbvax", 'v', BN|SN, | |
129 | "vax135", 'x', BN, | |
130 | "cory", 'y', SN, | |
131 | "eecs40", 'z', SN, | |
132 | 0, 0, 0 | |
133 | }; | |
134 | ||
135 | netlook(machine, attnet) | |
136 | char machine[]; | |
137 | { | |
138 | register struct netmach *np; | |
139 | register char *cp, *cp2; | |
140 | char nbuf[20]; | |
141 | ||
142 | /* | |
143 | * Make into lower case. | |
144 | */ | |
145 | ||
146 | for (cp = machine, cp2 = nbuf; *cp; *cp2++ = little(*cp++)) | |
147 | ; | |
148 | *cp2 = 0; | |
149 | ||
150 | /* | |
151 | * If a single letter machine, look through those first. | |
152 | */ | |
153 | ||
154 | if (strlen(nbuf) == 1) | |
155 | for (np = netmach; np->nt_mid != 0; np++) | |
156 | if (np->nt_mid == nbuf[0]) | |
157 | return(nbuf[0]); | |
158 | ||
159 | /* | |
160 | * Look for usual name | |
161 | */ | |
162 | ||
163 | for (np = netmach; np->nt_mid != 0; np++) | |
164 | if (strcmp(np->nt_machine, nbuf) == 0) | |
165 | return(np->nt_mid); | |
166 | ||
167 | /* | |
168 | * Look in side hash table. | |
169 | */ | |
170 | ||
171 | return(mstash(nbuf, attnet)); | |
172 | } | |
173 | ||
174 | /* | |
175 | * Make a little character. | |
176 | */ | |
177 | ||
178 | little(c) | |
179 | register int c; | |
180 | { | |
181 | ||
182 | if (c >= 'A' && c <= 'Z') | |
183 | c += 'a' - 'A'; | |
184 | return(c); | |
185 | } | |
186 | ||
187 | /* | |
188 | * Turn a network unique character identifier into a network name. | |
189 | */ | |
190 | ||
191 | char * | |
192 | netname(mid) | |
193 | { | |
194 | register struct netmach *np; | |
195 | char *mlook(); | |
196 | ||
197 | if (mid & 0200) | |
198 | return(mlook(mid)); | |
199 | for (np = netmach; np->nt_mid != 0; np++) | |
200 | if (np->nt_mid == mid) | |
201 | return(np->nt_machine); | |
202 | return(NOSTR); | |
203 | } | |
204 | ||
205 | /* | |
206 | * Deal with arpa net addresses. The way this is done is strange. | |
207 | * In particular, if the destination arpa net host is not Berkeley, | |
208 | * then the address is correct as stands. Otherwise, we strip off | |
209 | * the trailing @Berkeley, then cook up a phony person for it to | |
210 | * be from and optimize the result. | |
211 | */ | |
212 | char * | |
213 | arpafix(name, from) | |
214 | char name[]; | |
215 | char from[]; | |
216 | { | |
217 | register char *cp; | |
218 | register int arpamach; | |
219 | char newname[BUFSIZ]; | |
220 | char fake[5]; | |
221 | char fakepath[20]; | |
222 | ||
223 | if (debug) { | |
224 | fprintf(stderr, "arpafix(%s, %s)\n", name, from); | |
225 | } | |
226 | cp = rindex(name, '@'); | |
227 | if (cp == NOSTR) | |
228 | cp = rindex(name, '%'); | |
229 | if (cp == NOSTR) { | |
230 | fprintf(stderr, "Somethings amiss -- no @ or % in arpafix\n"); | |
231 | return(name); | |
232 | } | |
233 | cp++; | |
234 | arpamach = netlook(cp, '@'); | |
235 | if (arpamach == 0) { | |
236 | if (debug) | |
237 | fprintf(stderr, "machine %s unknown, uses: %s\n", cp, name); | |
238 | return(name); | |
239 | } | |
240 | if (((nettype(arpamach) & nettype(LOCAL)) & ~AN) == 0) { | |
241 | if (debug) | |
242 | fprintf(stderr, "machine %s known but remote, uses: %s\n", | |
243 | cp, name); | |
244 | return(name); | |
245 | } | |
246 | strcpy(newname, name); | |
247 | cp = rindex(newname, '@'); | |
248 | if (cp == NOSTR) | |
249 | cp = rindex(newname, '%'); | |
250 | *cp = 0; | |
251 | fake[0] = arpamach; | |
252 | fake[1] = ':'; | |
253 | fake[2] = LOCAL; | |
254 | fake[3] = ':'; | |
255 | fake[4] = 0; | |
256 | prefer(fake); | |
257 | strcpy(fakepath, netname(fake[0])); | |
258 | stradd(fakepath, fake[1]); | |
259 | strcat(fakepath, "daemon"); | |
260 | if (debug) | |
261 | fprintf(stderr, "machine local, call netmap(%s, %s)\n", | |
262 | newname, fakepath); | |
263 | return(netmap(newname, fakepath)); | |
264 | } | |
265 | ||
266 | /* | |
267 | * Take a network machine descriptor and find the types of connected | |
268 | * nets and return it. | |
269 | */ | |
270 | ||
271 | nettype(mid) | |
272 | { | |
273 | register struct netmach *np; | |
274 | ||
275 | if (mid & 0200) | |
276 | return(mtype(mid)); | |
277 | for (np = netmach; np->nt_mid != 0; np++) | |
278 | if (np->nt_mid == mid) | |
279 | return(np->nt_type); | |
280 | return(0); | |
281 | } | |
282 | ||
283 | /* | |
284 | * Hashing routines to salt away machines seen scanning | |
285 | * networks paths that we don't know about. | |
286 | */ | |
287 | ||
288 | #define XHSIZE 19 /* Size of extra hash table */ | |
289 | #define NXMID (XHSIZE*3/4) /* Max extra machines */ | |
290 | ||
291 | struct xtrahash { | |
292 | char *xh_name; /* Name of machine */ | |
293 | short xh_mid; /* Machine ID */ | |
294 | short xh_attnet; /* Attached networks */ | |
295 | } xtrahash[XHSIZE]; | |
296 | ||
297 | struct xtrahash *xtab[XHSIZE]; /* F: mid-->machine name */ | |
298 | ||
299 | short midfree; /* Next free machine id */ | |
300 | ||
301 | /* | |
302 | * Initialize the extra host hash table. | |
303 | * Called by sreset. | |
304 | */ | |
305 | ||
306 | minit() | |
307 | { | |
308 | register struct xtrahash *xp, **tp; | |
309 | register int i; | |
310 | ||
311 | midfree = 0; | |
312 | tp = &xtab[0]; | |
313 | for (xp = &xtrahash[0]; xp < &xtrahash[XHSIZE]; xp++) { | |
314 | xp->xh_name = NOSTR; | |
315 | xp->xh_mid = 0; | |
316 | xp->xh_attnet = 0; | |
317 | *tp++ = (struct xtrahash *) 0; | |
318 | } | |
319 | } | |
320 | ||
321 | /* | |
322 | * Stash a net name in the extra host hash table. | |
323 | * If a new entry is put in the hash table, deduce what | |
324 | * net the machine is attached to from the net character. | |
325 | * | |
326 | * If the machine is already known, add the given attached | |
327 | * net to those already known. | |
328 | */ | |
329 | ||
330 | mstash(name, attnet) | |
331 | char name[]; | |
332 | { | |
333 | register struct xtrahash *xp; | |
334 | struct xtrahash *xlocate(); | |
335 | ||
336 | xp = xlocate(name); | |
337 | if (xp == (struct xtrahash *) 0) { | |
338 | printf("Ran out of machine id spots\n"); | |
339 | return(0); | |
340 | } | |
341 | if (xp->xh_name == NOSTR) { | |
342 | if (midfree >= XHSIZE) { | |
343 | printf("Out of machine ids\n"); | |
344 | return(0); | |
345 | } | |
346 | xtab[midfree] = xp; | |
347 | xp->xh_name = savestr(name); | |
348 | xp->xh_mid = 0200 + midfree++; | |
349 | } | |
350 | switch (attnet) { | |
351 | case '!': | |
352 | case '^': | |
353 | xp->xh_attnet |= BN; | |
354 | break; | |
355 | ||
356 | default: | |
357 | case ':': | |
358 | xp->xh_attnet |= SN; | |
359 | break; | |
360 | ||
361 | case '@': | |
362 | case '%': | |
363 | xp->xh_attnet |= AN; | |
364 | break; | |
365 | } | |
366 | return(xp->xh_mid); | |
367 | } | |
368 | ||
369 | /* | |
370 | * Search for the given name in the hash table | |
371 | * and return the pointer to it if found, or to the first | |
372 | * empty slot if not found. | |
373 | * | |
374 | * If no free slots can be found, return 0. | |
375 | */ | |
376 | ||
377 | struct xtrahash * | |
378 | xlocate(name) | |
379 | char name[]; | |
380 | { | |
381 | register int h, q, i; | |
382 | register char *cp; | |
383 | register struct xtrahash *xp; | |
384 | ||
385 | for (h = 0, cp = name; *cp; h = (h << 2) + *cp++) | |
386 | ; | |
387 | if (h < 0 && (h = -h) < 0) | |
388 | h = 0; | |
389 | h = h % XHSIZE; | |
390 | cp = name; | |
391 | for (i = 0, q = 0; q < XHSIZE; i++, q = i * i) { | |
392 | xp = &xtrahash[(h + q) % XHSIZE]; | |
393 | if (xp->xh_name == NOSTR) | |
394 | return(xp); | |
395 | if (strcmp(cp, xp->xh_name) == 0) | |
396 | return(xp); | |
397 | if (h - q < 0) | |
398 | q += XHSIZE; | |
399 | xp = &xtrahash[(h - q) % XHSIZE]; | |
400 | if (xp->xh_name == NOSTR) | |
401 | return(xp); | |
402 | if (strcmp(cp, xp->xh_name) == 0) | |
403 | return(xp); | |
404 | } | |
405 | return((struct xtrahash *) 0); | |
406 | } | |
407 | ||
408 | /* | |
409 | * Return the name from the extra host hash table corresponding | |
410 | * to the passed machine id. | |
411 | */ | |
412 | ||
413 | char * | |
414 | mlook(mid) | |
415 | { | |
416 | register int m; | |
417 | ||
418 | if ((mid & 0200) == 0) | |
419 | return(NOSTR); | |
420 | m = mid & 0177; | |
421 | if (m >= midfree) { | |
422 | printf("Use made of undefined machine id\n"); | |
423 | return(NOSTR); | |
424 | } | |
425 | return(xtab[m]->xh_name); | |
426 | } | |
427 | ||
428 | /* | |
429 | * Return the bit mask of net's that the given extra host machine | |
430 | * id has so far. | |
431 | */ | |
432 | ||
433 | mtype(mid) | |
434 | { | |
435 | register int m; | |
436 | ||
437 | if ((mid & 0200) == 0) | |
438 | return(0); | |
439 | m = mid & 0177; | |
440 | if (m >= midfree) { | |
441 | printf("Use made of undefined machine id\n"); | |
442 | return(0); | |
443 | } | |
444 | return(xtab[m]->xh_attnet); | |
445 | } | |
446 | ||
447 | /* | |
448 | * Take a network name and optimize it. This gloriously messy | |
449 | * opertions takes place as follows: the name with machine names | |
450 | * in it is tokenized by mapping each machine name into a single | |
451 | * character machine id (netlook). The separator characters (network | |
452 | * metacharacters) are left intact. The last component of the network | |
453 | * name is stripped off and assumed to be the destination user name -- | |
454 | * it does not participate in the optimization. As an example, the | |
455 | * name "research!vax135!research!ucbvax!bill" becomes, tokenized, | |
456 | * "r!x!r!v!" and "bill" A low level routine, optim1, fixes up the | |
457 | * network part (eg, "r!x!r!v!"), then we convert back to network | |
458 | * machine names and tack the user name on the end. | |
459 | * | |
460 | * The result of this is copied into the parameter "name" | |
461 | */ | |
462 | ||
463 | optim(net, name) | |
464 | char net[], name[]; | |
465 | { | |
466 | char netcomp[BUFSIZ], netstr[40], xfstr[40]; | |
467 | register char *cp, *cp2; | |
468 | register int c; | |
469 | ||
470 | strcpy(netstr, ""); | |
471 | cp = net; | |
472 | for (;;) { | |
473 | /* | |
474 | * Rip off next path component into netcomp | |
475 | */ | |
476 | cp2 = netcomp; | |
477 | while (*cp && !any(*cp, metanet)) | |
478 | *cp2++ = *cp++; | |
479 | *cp2 = 0; | |
480 | /* | |
481 | * If we hit null byte, then we just scanned | |
482 | * the destination user name. Go off and optimize | |
483 | * if its so. | |
484 | */ | |
485 | if (*cp == 0) | |
486 | break; | |
487 | if ((c = netlook(netcomp, *cp)) == 0) { | |
488 | printf("No host named \"%s\"\n", netcomp); | |
489 | err: | |
490 | strcpy(name, net); | |
491 | return; | |
492 | } | |
493 | stradd(netstr, c); | |
494 | stradd(netstr, *cp++); | |
495 | /* | |
496 | * If multiple network separators given, | |
497 | * throw away the extras. | |
498 | */ | |
499 | while (any(*cp, metanet)) | |
500 | cp++; | |
501 | } | |
502 | if (strlen(netcomp) == 0) { | |
503 | printf("net name syntax\n"); | |
504 | goto err; | |
505 | } | |
506 | optim1(netstr, xfstr); | |
507 | ||
508 | /* | |
509 | * Convert back to machine names. | |
510 | */ | |
511 | ||
512 | cp = xfstr; | |
513 | strcpy(name, ""); | |
514 | while (*cp) { | |
515 | if ((cp2 = netname(*cp++)) == NOSTR) { | |
516 | printf("Made up bad net name\n"); | |
517 | goto err; | |
518 | } | |
519 | strcat(name, cp2); | |
520 | stradd(name, *cp++); | |
521 | } | |
522 | strcat(name, netcomp); | |
523 | } | |
524 | ||
525 | /* | |
526 | * Take a string of network machine id's and separators and | |
527 | * optimize them. We process these by pulling off maximal | |
528 | * leading strings of the same type, passing these to the appropriate | |
529 | * optimizer and concatenating the results. | |
530 | */ | |
531 | ||
532 | #define IMPLICIT 1 | |
533 | #define EXPLICIT 2 | |
534 | ||
535 | optim1(netstr, name) | |
536 | char netstr[], name[]; | |
537 | { | |
538 | char path[40], rpath[40]; | |
539 | register char *cp, *cp2; | |
540 | register int tp, nc; | |
541 | ||
542 | cp = netstr; | |
543 | prefer(cp); | |
544 | strcpy(name, ""); | |
545 | while (*cp != 0) { | |
546 | strcpy(path, ""); | |
547 | tp = ntype(cp[1]); | |
548 | nc = cp[1]; | |
549 | while (*cp && tp == ntype(cp[1])) { | |
550 | stradd(path, *cp++); | |
551 | cp++; | |
552 | } | |
553 | switch (netkind(tp)) { | |
554 | default: | |
555 | strcpy(rpath, path); | |
556 | break; | |
557 | ||
558 | case IMPLICIT: | |
559 | optimimp(path, rpath); | |
560 | break; | |
561 | ||
562 | case EXPLICIT: | |
563 | optimex(path, rpath); | |
564 | break; | |
565 | } | |
566 | for (cp2 = rpath; *cp2 != 0; cp2++) { | |
567 | stradd(name, *cp2); | |
568 | stradd(name, nc); | |
569 | } | |
570 | } | |
571 | optiboth(name); | |
572 | prefer(name); | |
573 | } | |
574 | ||
575 | /* | |
576 | * Return the network of the separator -- | |
577 | * AN for arpa net | |
578 | * BN for Bell labs net | |
579 | * SN for Schmidt (berkeley net) | |
580 | * 0 if we don't know. | |
581 | */ | |
582 | ||
583 | ntype(nc) | |
584 | register int nc; | |
585 | { | |
586 | ||
587 | switch (nc) { | |
588 | case '^': | |
589 | case '!': | |
590 | return(BN); | |
591 | ||
592 | case ':': | |
593 | case '.': | |
594 | return(SN); | |
595 | ||
596 | case '@': | |
597 | case '%': | |
598 | return(AN); | |
599 | ||
600 | default: | |
601 | return(0); | |
602 | } | |
603 | /* NOTREACHED */ | |
604 | } | |
605 | ||
606 | /* | |
607 | * Return the kind of routing used for the particular net | |
608 | * EXPLICIT means explicitly routed | |
609 | * IMPLICIT means implicitly routed | |
610 | * 0 means don't know | |
611 | */ | |
612 | ||
613 | netkind(nt) | |
614 | register int nt; | |
615 | { | |
616 | ||
617 | switch (nt) { | |
618 | case BN: | |
619 | return(EXPLICIT); | |
620 | ||
621 | case AN: | |
622 | case SN: | |
623 | return(IMPLICIT); | |
624 | ||
625 | default: | |
626 | return(0); | |
627 | } | |
628 | /* NOTREACHED */ | |
629 | } | |
630 | ||
631 | /* | |
632 | * Do name optimization for an explicitly routed network (eg BTL network). | |
633 | */ | |
634 | ||
635 | optimex(net, name) | |
636 | char net[], name[]; | |
637 | { | |
638 | register char *cp, *rp; | |
639 | register int m; | |
640 | char *rindex(); | |
641 | ||
642 | strcpy(name, net); | |
643 | cp = name; | |
644 | if (strlen(cp) == 0) | |
645 | return(-1); | |
646 | if (cp[strlen(cp)-1] == LOCAL) { | |
647 | name[0] = 0; | |
648 | return(0); | |
649 | } | |
650 | for (cp = name; *cp; cp++) { | |
651 | m = *cp; | |
652 | rp = rindex(cp+1, m); | |
653 | if (rp != NOSTR) | |
654 | strcpy(cp, rp); | |
655 | } | |
656 | return(0); | |
657 | } | |
658 | ||
659 | /* | |
660 | * Do name optimization for implicitly routed network (eg, arpanet, | |
661 | * Berkeley network) | |
662 | */ | |
663 | ||
664 | optimimp(net, name) | |
665 | char net[], name[]; | |
666 | { | |
667 | register char *cp; | |
668 | register int m; | |
669 | ||
670 | cp = net; | |
671 | if (strlen(cp) == 0) | |
672 | return(-1); | |
673 | m = cp[strlen(cp) - 1]; | |
674 | if (m == LOCAL) { | |
675 | strcpy(name, ""); | |
676 | return(0); | |
677 | } | |
678 | name[0] = m; | |
679 | name[1] = 0; | |
680 | return(0); | |
681 | } | |
682 | ||
683 | /* | |
684 | ||
685 | * Perform global optimization on the given network path. | |
686 | * The trick here is to look ahead to see if there are any loops | |
687 | * in the path and remove them. The interpretation of loops is | |
688 | * more strict here than in optimex since both the machine and net | |
689 | * type must match. | |
690 | */ | |
691 | ||
692 | optiboth(net) | |
693 | char net[]; | |
694 | { | |
695 | register char *cp, *cp2; | |
696 | char *rpair(); | |
697 | ||
698 | cp = net; | |
699 | if (strlen(cp) == 0) | |
700 | return; | |
701 | if ((strlen(cp) % 2) != 0) { | |
702 | printf("Strange arg to optiboth\n"); | |
703 | return; | |
704 | } | |
705 | while (*cp) { | |
706 | cp2 = rpair(cp+2, *cp); | |
707 | if (cp2 != NOSTR) | |
708 | strcpy(cp, cp2); | |
709 | cp += 2; | |
710 | } | |
711 | } | |
712 | ||
713 | /* | |
714 | * Find the rightmost instance of the given (machine, type) pair. | |
715 | */ | |
716 | ||
717 | char * | |
718 | rpair(str, mach) | |
719 | char str[]; | |
720 | { | |
721 | register char *cp, *last; | |
722 | ||
723 | last = NOSTR; | |
724 | while (*cp) { | |
725 | if (*cp == mach) | |
726 | last = cp; | |
727 | cp += 2; | |
728 | } | |
729 | return(last); | |
730 | } | |
731 | ||
732 | /* | |
733 | * Change the network separators in the given network path | |
734 | * to the preferred network transmission means. | |
735 | */ | |
736 | ||
737 | prefer(name) | |
738 | char name[]; | |
739 | { | |
740 | register char *cp; | |
741 | register int state, n; | |
742 | ||
743 | state = LOCAL; | |
744 | for (cp = name; *cp; cp += 2) { | |
745 | n = best(state, *cp); | |
746 | if (n) | |
747 | cp[1] = n; | |
748 | state = *cp; | |
749 | } | |
750 | } | |
751 | ||
752 | /* | |
753 | * Return the best network separator for the given machine pair. | |
754 | */ | |
755 | ||
756 | struct netorder { | |
757 | short no_stat; | |
758 | char no_char; | |
759 | } netorder[] = { | |
760 | CN, ':', | |
761 | AN, '@', | |
762 | AN, '%', | |
763 | SN, ':', | |
764 | BN, '!', | |
765 | -1, 0 | |
766 | }; | |
767 | ||
768 | best(src, dest) | |
769 | { | |
770 | register int dtype, stype; | |
771 | register struct netorder *np; | |
772 | ||
773 | stype = nettype(src); | |
774 | dtype = nettype(dest); | |
775 | if (stype == 0 || dtype == 0) { | |
776 | printf("ERROR: unknown internal machine id\n"); | |
777 | return(0); | |
778 | } | |
779 | if ((stype & dtype) == 0) { | |
780 | #ifdef DELIVERMAIL | |
781 | if (src != LOCAL) | |
782 | #endif | |
783 | printf("No way to get from \"%s\" to \"%s\"\n", | |
784 | netname(src), netname(dest)); | |
785 | return(0); | |
786 | } | |
787 | np = &netorder[0]; | |
788 | while ((np->no_stat & stype & dtype) == 0) | |
789 | np++; | |
790 | return(np->no_char); | |
791 | } | |
792 | ||
793 | /* | |
794 | * Code to twist around arpa net names. | |
795 | */ | |
796 | ||
797 | #define WORD 257 /* Token for a string */ | |
798 | ||
799 | static char netbuf[256]; | |
800 | static char *yylval; | |
801 | ||
802 | /* | |
803 | * Reverse all of the arpa net addresses in the given name to | |
804 | * be of the form "host @ user" instead of "user @ host" | |
805 | * This function is its own inverse. | |
806 | */ | |
807 | ||
808 | char * | |
809 | revarpa(str) | |
810 | char str[]; | |
811 | { | |
812 | ||
813 | if (yyinit(str) < 0) | |
814 | return(NOSTR); | |
815 | if (name()) | |
816 | return(NOSTR); | |
817 | if (strcmp(str, netbuf) == 0) | |
818 | return(str); | |
819 | return(savestr(netbuf)); | |
820 | } | |
821 | ||
822 | /* | |
823 | * Parse (by recursive descent) network names, using the following grammar: | |
824 | * name: | |
825 | * term {':' term} | |
826 | * term {'^' term} | |
827 | * term {'!' term} | |
828 | * term '@' name | |
829 | * term '%' name | |
830 | * | |
831 | * term: | |
832 | * string of characters. | |
833 | */ | |
834 | ||
835 | name() | |
836 | { | |
837 | register int t; | |
838 | register char *cp; | |
839 | ||
840 | for (;;) { | |
841 | t = yylex(); | |
842 | if (t != WORD) | |
843 | return(-1); | |
844 | cp = yylval; | |
845 | t = yylex(); | |
846 | switch (t) { | |
847 | case 0: | |
848 | strcat(netbuf, cp); | |
849 | return(0); | |
850 | ||
851 | case '@': | |
852 | case '%': | |
853 | if (name()) | |
854 | return(-1); | |
855 | stradd(netbuf, '@'); | |
856 | strcat(netbuf, cp); | |
857 | return(0); | |
858 | ||
859 | case WORD: | |
860 | return(-1); | |
861 | ||
862 | default: | |
863 | strcat(netbuf, cp); | |
864 | stradd(netbuf, t); | |
865 | } | |
866 | } | |
867 | } | |
868 | ||
869 | /* | |
870 | * Scanner for network names. | |
871 | */ | |
872 | ||
873 | static char *charp; /* Current input pointer */ | |
874 | static int nexttok; /* Salted away next token */ | |
875 | ||
876 | /* | |
877 | * Initialize the network name scanner. | |
878 | */ | |
879 | ||
880 | yyinit(str) | |
881 | char str[]; | |
882 | { | |
883 | static char lexbuf[BUFSIZ]; | |
884 | ||
885 | netbuf[0] = 0; | |
886 | if (strlen(str) >= sizeof lexbuf - 1) | |
887 | return(-1); | |
888 | nexttok = 0; | |
889 | strcpy(lexbuf, str); | |
890 | charp = lexbuf; | |
891 | return(0); | |
892 | } | |
893 | ||
894 | /* | |
895 | * Scan and return a single token. | |
896 | * yylval is set to point to a scanned string. | |
897 | */ | |
898 | ||
899 | yylex() | |
900 | { | |
901 | register char *cp, *dot; | |
902 | register int s; | |
903 | ||
904 | if (nexttok) { | |
905 | s = nexttok; | |
906 | nexttok = 0; | |
907 | return(s); | |
908 | } | |
909 | cp = charp; | |
910 | while (*cp && isspace(*cp)) | |
911 | cp++; | |
912 | if (*cp == 0) | |
913 | return(0); | |
914 | if (any(*cp, "!^@:%")) { | |
915 | charp = cp+1; | |
916 | return(*cp); | |
917 | } | |
918 | dot = cp; | |
919 | while (*cp && !any(*cp, " \t!^@:%")) | |
920 | cp++; | |
921 | if (any(*cp, "!^@:%")) | |
922 | nexttok = *cp; | |
923 | if (*cp == 0) | |
924 | charp = cp; | |
925 | else | |
926 | charp = cp+1; | |
927 | *cp = 0; | |
928 | yylval = dot; | |
929 | return(WORD); | |
930 | } | |
931 | ||
932 | /* | |
933 | * Add a single character onto a string. | |
934 | */ | |
935 | ||
936 | stradd(str, c) | |
937 | register char *str; | |
938 | register int c; | |
939 | { | |
940 | ||
941 | str += strlen(str); | |
942 | *str++ = c; | |
943 | *str = 0; | |
944 | } |