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" | |
6049dc7a | 10 | #include "configdefs.h" |
7537529b KS |
11 | #include <ctype.h> |
12 | ||
9d24b3cb | 13 | static char *SccsId = "@(#)optim.c 2.4 %G%"; |
7537529b KS |
14 | |
15 | /* | |
16 | * Map a name into the correct network "view" of the | |
17 | * name. This is done by prepending the name with the | |
18 | * network address of the sender, then optimizing away | |
19 | * nonsense. | |
20 | */ | |
21 | ||
7537529b KS |
22 | char * |
23 | netmap(name, from) | |
24 | char name[], from[]; | |
25 | { | |
26 | char nbuf[BUFSIZ], ret[BUFSIZ]; | |
27 | register char *cp; | |
28 | ||
29 | if (strlen(from) == 0) | |
30 | return(name); | |
31 | if (any('@', name) || any('%', name)) | |
32 | return(arpafix(name, from)); | |
33 | cp = revarpa(from); | |
34 | if (cp == NOSTR) | |
35 | return(name); | |
36 | strcpy(nbuf, cp); | |
37 | cp = &nbuf[strlen(nbuf) - 1]; | |
38 | while (!any(*cp, metanet) && cp > nbuf) | |
39 | cp--; | |
40 | if (cp == nbuf) | |
41 | return(name); | |
42 | *++cp = 0; | |
43 | strcat(nbuf, revarpa(name)); | |
44 | optim(nbuf, ret); | |
45 | cp = revarpa(ret); | |
46 | if (!icequal(name, cp)) | |
47 | return((char *) savestr(cp)); | |
48 | return(name); | |
49 | } | |
50 | ||
51 | /* | |
52 | * Rename the given network path to use | |
53 | * the kinds of names that we would right here. | |
54 | */ | |
55 | ||
56 | char * | |
57 | rename(str) | |
58 | char str[]; | |
59 | { | |
60 | register char *cp, *cp2; | |
61 | char buf[BUFSIZ], path[BUFSIZ]; | |
62 | register int c, host; | |
63 | ||
64 | strcpy(path, ""); | |
65 | for (;;) { | |
66 | if ((c = *cp++) == 0) | |
67 | break; | |
68 | cp2 = buf; | |
69 | while (!any(c, metanet) && c != 0) { | |
70 | *cp2++ = c; | |
71 | c = *cp++; | |
72 | } | |
73 | *cp2 = 0; | |
74 | if (c == 0) { | |
75 | strcat(path, buf); | |
76 | break; | |
77 | } | |
78 | host = netlook(buf, ntype(c)); | |
79 | strcat(path, netname(host)); | |
80 | stradd(path, c); | |
81 | } | |
82 | if (strcmp(str, path) != 0) | |
83 | return(savestr(path)); | |
84 | return(str); | |
85 | } | |
6049dc7a | 86 | |
7537529b KS |
87 | /* |
88 | * Turn a network machine name into a unique character | |
7537529b | 89 | */ |
7537529b KS |
90 | netlook(machine, attnet) |
91 | char machine[]; | |
92 | { | |
93 | register struct netmach *np; | |
94 | register char *cp, *cp2; | |
95 | char nbuf[20]; | |
96 | ||
97 | /* | |
98 | * Make into lower case. | |
99 | */ | |
100 | ||
101 | for (cp = machine, cp2 = nbuf; *cp; *cp2++ = little(*cp++)) | |
102 | ; | |
103 | *cp2 = 0; | |
104 | ||
105 | /* | |
106 | * If a single letter machine, look through those first. | |
107 | */ | |
108 | ||
109 | if (strlen(nbuf) == 1) | |
110 | for (np = netmach; np->nt_mid != 0; np++) | |
111 | if (np->nt_mid == nbuf[0]) | |
112 | return(nbuf[0]); | |
113 | ||
114 | /* | |
115 | * Look for usual name | |
116 | */ | |
117 | ||
118 | for (np = netmach; np->nt_mid != 0; np++) | |
119 | if (strcmp(np->nt_machine, nbuf) == 0) | |
120 | return(np->nt_mid); | |
121 | ||
122 | /* | |
123 | * Look in side hash table. | |
124 | */ | |
125 | ||
126 | return(mstash(nbuf, attnet)); | |
127 | } | |
128 | ||
129 | /* | |
130 | * Make a little character. | |
131 | */ | |
132 | ||
133 | little(c) | |
134 | register int c; | |
135 | { | |
136 | ||
137 | if (c >= 'A' && c <= 'Z') | |
138 | c += 'a' - 'A'; | |
139 | return(c); | |
140 | } | |
141 | ||
142 | /* | |
143 | * Turn a network unique character identifier into a network name. | |
144 | */ | |
145 | ||
146 | char * | |
147 | netname(mid) | |
148 | { | |
149 | register struct netmach *np; | |
150 | char *mlook(); | |
151 | ||
152 | if (mid & 0200) | |
153 | return(mlook(mid)); | |
154 | for (np = netmach; np->nt_mid != 0; np++) | |
155 | if (np->nt_mid == mid) | |
156 | return(np->nt_machine); | |
157 | return(NOSTR); | |
158 | } | |
159 | ||
160 | /* | |
161 | * Deal with arpa net addresses. The way this is done is strange. | |
162 | * In particular, if the destination arpa net host is not Berkeley, | |
163 | * then the address is correct as stands. Otherwise, we strip off | |
164 | * the trailing @Berkeley, then cook up a phony person for it to | |
165 | * be from and optimize the result. | |
166 | */ | |
167 | char * | |
168 | arpafix(name, from) | |
169 | char name[]; | |
170 | char from[]; | |
171 | { | |
172 | register char *cp; | |
173 | register int arpamach; | |
174 | char newname[BUFSIZ]; | |
175 | char fake[5]; | |
176 | char fakepath[20]; | |
177 | ||
178 | if (debug) { | |
179 | fprintf(stderr, "arpafix(%s, %s)\n", name, from); | |
180 | } | |
181 | cp = rindex(name, '@'); | |
182 | if (cp == NOSTR) | |
183 | cp = rindex(name, '%'); | |
184 | if (cp == NOSTR) { | |
185 | fprintf(stderr, "Somethings amiss -- no @ or % in arpafix\n"); | |
186 | return(name); | |
187 | } | |
188 | cp++; | |
189 | arpamach = netlook(cp, '@'); | |
190 | if (arpamach == 0) { | |
191 | if (debug) | |
192 | fprintf(stderr, "machine %s unknown, uses: %s\n", cp, name); | |
193 | return(name); | |
194 | } | |
195 | if (((nettype(arpamach) & nettype(LOCAL)) & ~AN) == 0) { | |
196 | if (debug) | |
197 | fprintf(stderr, "machine %s known but remote, uses: %s\n", | |
198 | cp, name); | |
199 | return(name); | |
200 | } | |
201 | strcpy(newname, name); | |
202 | cp = rindex(newname, '@'); | |
203 | if (cp == NOSTR) | |
204 | cp = rindex(newname, '%'); | |
205 | *cp = 0; | |
206 | fake[0] = arpamach; | |
207 | fake[1] = ':'; | |
208 | fake[2] = LOCAL; | |
209 | fake[3] = ':'; | |
210 | fake[4] = 0; | |
211 | prefer(fake); | |
212 | strcpy(fakepath, netname(fake[0])); | |
213 | stradd(fakepath, fake[1]); | |
214 | strcat(fakepath, "daemon"); | |
215 | if (debug) | |
216 | fprintf(stderr, "machine local, call netmap(%s, %s)\n", | |
217 | newname, fakepath); | |
218 | return(netmap(newname, fakepath)); | |
219 | } | |
220 | ||
221 | /* | |
222 | * Take a network machine descriptor and find the types of connected | |
223 | * nets and return it. | |
224 | */ | |
225 | ||
226 | nettype(mid) | |
227 | { | |
228 | register struct netmach *np; | |
229 | ||
230 | if (mid & 0200) | |
231 | return(mtype(mid)); | |
232 | for (np = netmach; np->nt_mid != 0; np++) | |
233 | if (np->nt_mid == mid) | |
234 | return(np->nt_type); | |
235 | return(0); | |
236 | } | |
237 | ||
238 | /* | |
239 | * Hashing routines to salt away machines seen scanning | |
240 | * networks paths that we don't know about. | |
241 | */ | |
242 | ||
243 | #define XHSIZE 19 /* Size of extra hash table */ | |
244 | #define NXMID (XHSIZE*3/4) /* Max extra machines */ | |
245 | ||
246 | struct xtrahash { | |
247 | char *xh_name; /* Name of machine */ | |
248 | short xh_mid; /* Machine ID */ | |
249 | short xh_attnet; /* Attached networks */ | |
250 | } xtrahash[XHSIZE]; | |
251 | ||
252 | struct xtrahash *xtab[XHSIZE]; /* F: mid-->machine name */ | |
253 | ||
254 | short midfree; /* Next free machine id */ | |
255 | ||
256 | /* | |
257 | * Initialize the extra host hash table. | |
258 | * Called by sreset. | |
259 | */ | |
260 | ||
261 | minit() | |
262 | { | |
263 | register struct xtrahash *xp, **tp; | |
264 | register int i; | |
265 | ||
266 | midfree = 0; | |
267 | tp = &xtab[0]; | |
268 | for (xp = &xtrahash[0]; xp < &xtrahash[XHSIZE]; xp++) { | |
269 | xp->xh_name = NOSTR; | |
270 | xp->xh_mid = 0; | |
271 | xp->xh_attnet = 0; | |
272 | *tp++ = (struct xtrahash *) 0; | |
273 | } | |
274 | } | |
275 | ||
276 | /* | |
277 | * Stash a net name in the extra host hash table. | |
278 | * If a new entry is put in the hash table, deduce what | |
279 | * net the machine is attached to from the net character. | |
280 | * | |
281 | * If the machine is already known, add the given attached | |
282 | * net to those already known. | |
283 | */ | |
284 | ||
285 | mstash(name, attnet) | |
286 | char name[]; | |
287 | { | |
288 | register struct xtrahash *xp; | |
289 | struct xtrahash *xlocate(); | |
6049dc7a | 290 | int x; |
7537529b KS |
291 | |
292 | xp = xlocate(name); | |
293 | if (xp == (struct xtrahash *) 0) { | |
294 | printf("Ran out of machine id spots\n"); | |
295 | return(0); | |
296 | } | |
297 | if (xp->xh_name == NOSTR) { | |
298 | if (midfree >= XHSIZE) { | |
299 | printf("Out of machine ids\n"); | |
300 | return(0); | |
301 | } | |
302 | xtab[midfree] = xp; | |
303 | xp->xh_name = savestr(name); | |
304 | xp->xh_mid = 0200 + midfree++; | |
305 | } | |
6049dc7a KS |
306 | x = ntype(attnet); |
307 | if (x == 0) | |
7537529b | 308 | xp->xh_attnet |= SN; |
6049dc7a KS |
309 | else |
310 | xp->xh_attnet |= x; | |
7537529b KS |
311 | return(xp->xh_mid); |
312 | } | |
313 | ||
314 | /* | |
315 | * Search for the given name in the hash table | |
316 | * and return the pointer to it if found, or to the first | |
317 | * empty slot if not found. | |
318 | * | |
319 | * If no free slots can be found, return 0. | |
320 | */ | |
321 | ||
322 | struct xtrahash * | |
323 | xlocate(name) | |
324 | char name[]; | |
325 | { | |
326 | register int h, q, i; | |
327 | register char *cp; | |
328 | register struct xtrahash *xp; | |
329 | ||
330 | for (h = 0, cp = name; *cp; h = (h << 2) + *cp++) | |
331 | ; | |
332 | if (h < 0 && (h = -h) < 0) | |
333 | h = 0; | |
334 | h = h % XHSIZE; | |
335 | cp = name; | |
336 | for (i = 0, q = 0; q < XHSIZE; i++, q = i * i) { | |
337 | xp = &xtrahash[(h + q) % XHSIZE]; | |
338 | if (xp->xh_name == NOSTR) | |
339 | return(xp); | |
340 | if (strcmp(cp, xp->xh_name) == 0) | |
341 | return(xp); | |
342 | if (h - q < 0) | |
343 | q += XHSIZE; | |
344 | xp = &xtrahash[(h - q) % XHSIZE]; | |
345 | if (xp->xh_name == NOSTR) | |
346 | return(xp); | |
347 | if (strcmp(cp, xp->xh_name) == 0) | |
348 | return(xp); | |
349 | } | |
350 | return((struct xtrahash *) 0); | |
351 | } | |
352 | ||
353 | /* | |
354 | * Return the name from the extra host hash table corresponding | |
355 | * to the passed machine id. | |
356 | */ | |
357 | ||
358 | char * | |
359 | mlook(mid) | |
360 | { | |
361 | register int m; | |
362 | ||
363 | if ((mid & 0200) == 0) | |
364 | return(NOSTR); | |
365 | m = mid & 0177; | |
366 | if (m >= midfree) { | |
367 | printf("Use made of undefined machine id\n"); | |
368 | return(NOSTR); | |
369 | } | |
370 | return(xtab[m]->xh_name); | |
371 | } | |
372 | ||
373 | /* | |
374 | * Return the bit mask of net's that the given extra host machine | |
375 | * id has so far. | |
376 | */ | |
377 | ||
378 | mtype(mid) | |
379 | { | |
380 | register int m; | |
381 | ||
382 | if ((mid & 0200) == 0) | |
383 | return(0); | |
384 | m = mid & 0177; | |
385 | if (m >= midfree) { | |
386 | printf("Use made of undefined machine id\n"); | |
387 | return(0); | |
388 | } | |
389 | return(xtab[m]->xh_attnet); | |
390 | } | |
391 | ||
392 | /* | |
393 | * Take a network name and optimize it. This gloriously messy | |
bedc7b35 | 394 | * operation takes place as follows: the name with machine names |
7537529b KS |
395 | * in it is tokenized by mapping each machine name into a single |
396 | * character machine id (netlook). The separator characters (network | |
397 | * metacharacters) are left intact. The last component of the network | |
398 | * name is stripped off and assumed to be the destination user name -- | |
399 | * it does not participate in the optimization. As an example, the | |
400 | * name "research!vax135!research!ucbvax!bill" becomes, tokenized, | |
401 | * "r!x!r!v!" and "bill" A low level routine, optim1, fixes up the | |
402 | * network part (eg, "r!x!r!v!"), then we convert back to network | |
403 | * machine names and tack the user name on the end. | |
404 | * | |
405 | * The result of this is copied into the parameter "name" | |
406 | */ | |
407 | ||
408 | optim(net, name) | |
409 | char net[], name[]; | |
410 | { | |
411 | char netcomp[BUFSIZ], netstr[40], xfstr[40]; | |
412 | register char *cp, *cp2; | |
413 | register int c; | |
414 | ||
415 | strcpy(netstr, ""); | |
416 | cp = net; | |
417 | for (;;) { | |
418 | /* | |
419 | * Rip off next path component into netcomp | |
420 | */ | |
421 | cp2 = netcomp; | |
422 | while (*cp && !any(*cp, metanet)) | |
423 | *cp2++ = *cp++; | |
424 | *cp2 = 0; | |
425 | /* | |
426 | * If we hit null byte, then we just scanned | |
427 | * the destination user name. Go off and optimize | |
428 | * if its so. | |
429 | */ | |
430 | if (*cp == 0) | |
431 | break; | |
432 | if ((c = netlook(netcomp, *cp)) == 0) { | |
433 | printf("No host named \"%s\"\n", netcomp); | |
434 | err: | |
435 | strcpy(name, net); | |
436 | return; | |
437 | } | |
438 | stradd(netstr, c); | |
439 | stradd(netstr, *cp++); | |
440 | /* | |
441 | * If multiple network separators given, | |
442 | * throw away the extras. | |
443 | */ | |
444 | while (any(*cp, metanet)) | |
445 | cp++; | |
446 | } | |
447 | if (strlen(netcomp) == 0) { | |
448 | printf("net name syntax\n"); | |
449 | goto err; | |
450 | } | |
451 | optim1(netstr, xfstr); | |
452 | ||
453 | /* | |
454 | * Convert back to machine names. | |
455 | */ | |
456 | ||
457 | cp = xfstr; | |
458 | strcpy(name, ""); | |
459 | while (*cp) { | |
460 | if ((cp2 = netname(*cp++)) == NOSTR) { | |
461 | printf("Made up bad net name\n"); | |
34e33c1a KS |
462 | printf("Machine code %c (0%o)\n", cp[-1], cp[-1]); |
463 | printf("Sorry -- dumping now. Alert K. Shoens\n"); | |
464 | core(0); | |
7537529b KS |
465 | goto err; |
466 | } | |
467 | strcat(name, cp2); | |
468 | stradd(name, *cp++); | |
469 | } | |
470 | strcat(name, netcomp); | |
471 | } | |
472 | ||
473 | /* | |
474 | * Take a string of network machine id's and separators and | |
475 | * optimize them. We process these by pulling off maximal | |
476 | * leading strings of the same type, passing these to the appropriate | |
477 | * optimizer and concatenating the results. | |
478 | */ | |
479 | ||
7537529b KS |
480 | optim1(netstr, name) |
481 | char netstr[], name[]; | |
482 | { | |
483 | char path[40], rpath[40]; | |
484 | register char *cp, *cp2; | |
485 | register int tp, nc; | |
486 | ||
487 | cp = netstr; | |
488 | prefer(cp); | |
9d24b3cb | 489 | strcpy(name, ""); |
bedc7b35 KS |
490 | /* |
491 | * If the address ultimately points back to us, | |
492 | * just return a null network path. | |
493 | */ | |
494 | if (strlen(cp) > 1 && cp[strlen(cp) - 2] == LOCAL) | |
495 | return; | |
7537529b KS |
496 | while (*cp != 0) { |
497 | strcpy(path, ""); | |
498 | tp = ntype(cp[1]); | |
499 | nc = cp[1]; | |
500 | while (*cp && tp == ntype(cp[1])) { | |
501 | stradd(path, *cp++); | |
502 | cp++; | |
503 | } | |
504 | switch (netkind(tp)) { | |
505 | default: | |
506 | strcpy(rpath, path); | |
507 | break; | |
508 | ||
509 | case IMPLICIT: | |
510 | optimimp(path, rpath); | |
511 | break; | |
512 | ||
513 | case EXPLICIT: | |
514 | optimex(path, rpath); | |
515 | break; | |
516 | } | |
517 | for (cp2 = rpath; *cp2 != 0; cp2++) { | |
518 | stradd(name, *cp2); | |
519 | stradd(name, nc); | |
520 | } | |
521 | } | |
522 | optiboth(name); | |
523 | prefer(name); | |
524 | } | |
525 | ||
526 | /* | |
527 | * Return the network of the separator -- | |
528 | * AN for arpa net | |
529 | * BN for Bell labs net | |
530 | * SN for Schmidt (berkeley net) | |
531 | * 0 if we don't know. | |
532 | */ | |
533 | ||
534 | ntype(nc) | |
535 | register int nc; | |
536 | { | |
6049dc7a | 537 | register struct nettypetab *np; |
7537529b | 538 | |
6049dc7a KS |
539 | for (np = nettypetab; np->nt_char != 0; np++) |
540 | if (np->nt_char == nc) | |
541 | return(np->nt_type); | |
542 | return(0); | |
7537529b KS |
543 | } |
544 | ||
545 | /* | |
546 | * Return the kind of routing used for the particular net | |
547 | * EXPLICIT means explicitly routed | |
548 | * IMPLICIT means implicitly routed | |
549 | * 0 means don't know | |
550 | */ | |
551 | ||
552 | netkind(nt) | |
553 | register int nt; | |
554 | { | |
6049dc7a | 555 | register struct netkindtab *np; |
7537529b | 556 | |
6049dc7a KS |
557 | for (np = netkindtab; np->nk_type != 0; np++) |
558 | if (np->nk_type == nt) | |
559 | return(np->nk_kind); | |
560 | return(0); | |
7537529b KS |
561 | } |
562 | ||
563 | /* | |
564 | * Do name optimization for an explicitly routed network (eg BTL network). | |
565 | */ | |
566 | ||
567 | optimex(net, name) | |
568 | char net[], name[]; | |
569 | { | |
570 | register char *cp, *rp; | |
571 | register int m; | |
572 | char *rindex(); | |
573 | ||
574 | strcpy(name, net); | |
575 | cp = name; | |
576 | if (strlen(cp) == 0) | |
577 | return(-1); | |
578 | if (cp[strlen(cp)-1] == LOCAL) { | |
579 | name[0] = 0; | |
580 | return(0); | |
581 | } | |
582 | for (cp = name; *cp; cp++) { | |
583 | m = *cp; | |
584 | rp = rindex(cp+1, m); | |
585 | if (rp != NOSTR) | |
586 | strcpy(cp, rp); | |
587 | } | |
588 | return(0); | |
589 | } | |
590 | ||
591 | /* | |
592 | * Do name optimization for implicitly routed network (eg, arpanet, | |
593 | * Berkeley network) | |
594 | */ | |
595 | ||
596 | optimimp(net, name) | |
597 | char net[], name[]; | |
598 | { | |
599 | register char *cp; | |
600 | register int m; | |
601 | ||
602 | cp = net; | |
603 | if (strlen(cp) == 0) | |
604 | return(-1); | |
605 | m = cp[strlen(cp) - 1]; | |
606 | if (m == LOCAL) { | |
607 | strcpy(name, ""); | |
608 | return(0); | |
609 | } | |
610 | name[0] = m; | |
611 | name[1] = 0; | |
612 | return(0); | |
613 | } | |
614 | ||
615 | /* | |
7537529b KS |
616 | * Perform global optimization on the given network path. |
617 | * The trick here is to look ahead to see if there are any loops | |
618 | * in the path and remove them. The interpretation of loops is | |
619 | * more strict here than in optimex since both the machine and net | |
620 | * type must match. | |
621 | */ | |
622 | ||
623 | optiboth(net) | |
624 | char net[]; | |
625 | { | |
626 | register char *cp, *cp2; | |
627 | char *rpair(); | |
628 | ||
629 | cp = net; | |
630 | if (strlen(cp) == 0) | |
631 | return; | |
632 | if ((strlen(cp) % 2) != 0) { | |
633 | printf("Strange arg to optiboth\n"); | |
634 | return; | |
635 | } | |
636 | while (*cp) { | |
637 | cp2 = rpair(cp+2, *cp); | |
638 | if (cp2 != NOSTR) | |
639 | strcpy(cp, cp2); | |
640 | cp += 2; | |
641 | } | |
642 | } | |
643 | ||
644 | /* | |
645 | * Find the rightmost instance of the given (machine, type) pair. | |
646 | */ | |
647 | ||
648 | char * | |
649 | rpair(str, mach) | |
650 | char str[]; | |
651 | { | |
652 | register char *cp, *last; | |
653 | ||
654 | last = NOSTR; | |
655 | while (*cp) { | |
656 | if (*cp == mach) | |
657 | last = cp; | |
658 | cp += 2; | |
659 | } | |
660 | return(last); | |
661 | } | |
662 | ||
663 | /* | |
664 | * Change the network separators in the given network path | |
665 | * to the preferred network transmission means. | |
666 | */ | |
667 | ||
668 | prefer(name) | |
669 | char name[]; | |
670 | { | |
671 | register char *cp; | |
672 | register int state, n; | |
673 | ||
674 | state = LOCAL; | |
675 | for (cp = name; *cp; cp += 2) { | |
676 | n = best(state, *cp); | |
677 | if (n) | |
678 | cp[1] = n; | |
679 | state = *cp; | |
680 | } | |
681 | } | |
682 | ||
683 | /* | |
684 | * Return the best network separator for the given machine pair. | |
685 | */ | |
686 | ||
7537529b KS |
687 | best(src, dest) |
688 | { | |
689 | register int dtype, stype; | |
690 | register struct netorder *np; | |
691 | ||
692 | stype = nettype(src); | |
693 | dtype = nettype(dest); | |
bedc7b35 | 694 | fflush(stdout); |
7537529b KS |
695 | if (stype == 0 || dtype == 0) { |
696 | printf("ERROR: unknown internal machine id\n"); | |
697 | return(0); | |
698 | } | |
bedc7b35 | 699 | if ((stype & dtype) == 0) |
7537529b | 700 | return(0); |
7537529b KS |
701 | np = &netorder[0]; |
702 | while ((np->no_stat & stype & dtype) == 0) | |
703 | np++; | |
704 | return(np->no_char); | |
705 | } | |
706 | ||
707 | /* | |
708 | * Code to twist around arpa net names. | |
709 | */ | |
710 | ||
711 | #define WORD 257 /* Token for a string */ | |
712 | ||
713 | static char netbuf[256]; | |
714 | static char *yylval; | |
715 | ||
716 | /* | |
717 | * Reverse all of the arpa net addresses in the given name to | |
718 | * be of the form "host @ user" instead of "user @ host" | |
719 | * This function is its own inverse. | |
720 | */ | |
721 | ||
722 | char * | |
723 | revarpa(str) | |
724 | char str[]; | |
725 | { | |
726 | ||
727 | if (yyinit(str) < 0) | |
728 | return(NOSTR); | |
729 | if (name()) | |
730 | return(NOSTR); | |
731 | if (strcmp(str, netbuf) == 0) | |
732 | return(str); | |
733 | return(savestr(netbuf)); | |
734 | } | |
735 | ||
736 | /* | |
737 | * Parse (by recursive descent) network names, using the following grammar: | |
738 | * name: | |
739 | * term {':' term} | |
740 | * term {'^' term} | |
741 | * term {'!' term} | |
742 | * term '@' name | |
743 | * term '%' name | |
744 | * | |
745 | * term: | |
746 | * string of characters. | |
747 | */ | |
748 | ||
749 | name() | |
750 | { | |
751 | register int t; | |
752 | register char *cp; | |
753 | ||
754 | for (;;) { | |
755 | t = yylex(); | |
756 | if (t != WORD) | |
757 | return(-1); | |
758 | cp = yylval; | |
759 | t = yylex(); | |
760 | switch (t) { | |
761 | case 0: | |
762 | strcat(netbuf, cp); | |
763 | return(0); | |
764 | ||
765 | case '@': | |
766 | case '%': | |
767 | if (name()) | |
768 | return(-1); | |
769 | stradd(netbuf, '@'); | |
770 | strcat(netbuf, cp); | |
771 | return(0); | |
772 | ||
773 | case WORD: | |
774 | return(-1); | |
775 | ||
776 | default: | |
777 | strcat(netbuf, cp); | |
778 | stradd(netbuf, t); | |
779 | } | |
780 | } | |
781 | } | |
782 | ||
783 | /* | |
784 | * Scanner for network names. | |
785 | */ | |
786 | ||
787 | static char *charp; /* Current input pointer */ | |
788 | static int nexttok; /* Salted away next token */ | |
789 | ||
790 | /* | |
791 | * Initialize the network name scanner. | |
792 | */ | |
793 | ||
794 | yyinit(str) | |
795 | char str[]; | |
796 | { | |
797 | static char lexbuf[BUFSIZ]; | |
798 | ||
799 | netbuf[0] = 0; | |
800 | if (strlen(str) >= sizeof lexbuf - 1) | |
801 | return(-1); | |
802 | nexttok = 0; | |
803 | strcpy(lexbuf, str); | |
804 | charp = lexbuf; | |
805 | return(0); | |
806 | } | |
807 | ||
808 | /* | |
809 | * Scan and return a single token. | |
810 | * yylval is set to point to a scanned string. | |
811 | */ | |
812 | ||
813 | yylex() | |
814 | { | |
815 | register char *cp, *dot; | |
816 | register int s; | |
817 | ||
818 | if (nexttok) { | |
819 | s = nexttok; | |
820 | nexttok = 0; | |
821 | return(s); | |
822 | } | |
823 | cp = charp; | |
824 | while (*cp && isspace(*cp)) | |
825 | cp++; | |
826 | if (*cp == 0) | |
827 | return(0); | |
6049dc7a | 828 | if (any(*cp, metanet)) { |
7537529b KS |
829 | charp = cp+1; |
830 | return(*cp); | |
831 | } | |
832 | dot = cp; | |
6049dc7a | 833 | while (*cp && !any(*cp, metanet) && !any(*cp, " \t")) |
7537529b | 834 | cp++; |
6049dc7a | 835 | if (any(*cp, metanet)) |
7537529b KS |
836 | nexttok = *cp; |
837 | if (*cp == 0) | |
838 | charp = cp; | |
839 | else | |
840 | charp = cp+1; | |
841 | *cp = 0; | |
842 | yylval = dot; | |
843 | return(WORD); | |
844 | } | |
845 | ||
846 | /* | |
847 | * Add a single character onto a string. | |
848 | */ | |
849 | ||
850 | stradd(str, c) | |
851 | register char *str; | |
852 | register int c; | |
853 | { | |
854 | ||
855 | str += strlen(str); | |
856 | *str++ = c; | |
857 | *str = 0; | |
858 | } |