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Date:: Tue Nov 27 20:39:06 2007 UTC
Message:: merge
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1 /*
2  * Locking here is not quite right.
3  * Calling qlock(&z->lk) can block the proc,
4  * and when it comes back, boxes and msgs might have been freed
5  * (if the refresh proc was holding the lock and in the middle of a
6  * redial).  I've tried to be careful about not assuming boxes continue
7  * to exist across imap commands, but maybe this isn't really tenable.
8  * Maybe instead we should ref count the boxes and messages.
9  */
10 
11 #include "a.h"
12 #include <libsec.h>
13 
14 struct Imap
15 {
16 	int		connected;
17 	int		autoreconnect;
18 	int		ticks;	/* until boom! */
19 	char*	server;
20 	char*	root;
21 	int		mode;
22 	int		fd;
23 	Biobuf	b;
24 	Ioproc*	io;
25 	QLock	lk;
26 	QLock	rlk;
27 	Rendez	r;
28 
29 	Box*		inbox;
30 	Box*		box;
31 	Box*		nextbox;
32 
33 	/* SEARCH results */
34 	uint		*uid;
35 	uint		nuid;
36 };
37 
38 static struct {
39 	char *name;
40 	int flag;
41 } flagstab[] = 
42 {
43 	"Junk",	FlagJunk,
44 	"NonJunk",	FlagNonJunk,
45 	"\\Answered",	FlagReplied,
46 	"\\Flagged",	FlagFlagged,
47 	"\\Deleted",	FlagDeleted,
48 	"\\Draft",		FlagDraft,
49 	"\\Recent",	FlagRecent,
50 	"\\Seen",		FlagSeen,
51 	"\\NoInferiors",	FlagNoInferiors,
52 	"\\NoSelect",	FlagNoSelect,
53 	"\\Marked",	FlagMarked,
54 	"\\UnMarked",	FlagUnMarked
55 };
56 
57 int			chattyimap;
58 
59 static char	*tag = "#";
60 
61 static void	checkbox(Imap*, Box*);
62 static char*	copyaddrs(Sx*);
63 static void	freeup(UserPasswd*);
64 static int		getbox(Imap*, Box*);
65 static int		getboxes(Imap*);
66 static char*	gsub(char*, char*, char*);
67 static int		imapcmd(Imap*, Box*, char*, ...);
68 static Sx*		imapcmdsx(Imap*, Box*, char*, ...);
69 static Sx*		imapcmdsx0(Imap*, char*, ...);
70 static Sx*		imapvcmdsx(Imap*, Box*, char*, va_list);
71 static Sx*		imapvcmdsx0(Imap*, char*, va_list);
72 static int		imapdial(char*, int);
73 static int		imaplogin(Imap*);
74 static int		imapquote(Fmt*);
75 static int		imapreconnect(Imap*);
76 static void	imaprefreshthread(void*);
77 static void	imaptimerproc(void*);
78 static Sx*		imapwaitsx(Imap*);
79 static int		isatom(Sx *v, char *name);
80 static int		islist(Sx *v);
81 static int		isnil(Sx *v);
82 static int		isnumber(Sx *sx);
83 static int		isstring(Sx *sx);
84 static int		ioimapdial(Ioproc*, char*, int);
85 static char*	nstring(Sx*);
86 static void	unexpected(Imap*, Sx*);
87 static Sx*		zBrdsx(Imap*);
88 
89 /*
90  * Imap connection maintenance and login.
91  */
92 
93 Imap*
94 imapconnect(char *server, int mode, char *root)
95 {
96 	Imap *z;
97 
98 	fmtinstall('H', encodefmt);
99 	fmtinstall('Z', imapquote);
100 
101 	z = emalloc(sizeof *z);
102 	z->server = estrdup(server);
103 	z->mode = mode;
104 	if(root)
105 		if(root[0] != 0 && root[strlen(root)-1] != '/')
106 			z->root = smprint("%s/", root);
107 		else
108 			z->root = root;
109 	else
110 		z->root = "";
111 	z->fd = -1;
112 	z->autoreconnect = 0;
113 	z->io = ioproc();
114 	
115 	qlock(&z->lk);
116 	if(imapreconnect(z) < 0){
117 		free(z);
118 		return nil;
119 	}
120 	
121 	z->r.l = &z->rlk;
122 	z->autoreconnect = 1;
123 	qunlock(&z->lk);
124 	
125 	proccreate(imaptimerproc, z, STACK);
126 	mailthread(imaprefreshthread, z);
127 	
128 	return z;
129 }
130 
131 void
132 imaphangup(Imap *z, int ticks)
133 {
134 	z->ticks = ticks;
135 	if(ticks == 0){
136 		close(z->fd);
137 		z->fd = -1;
138 	}
139 }
140 
141 static int
142 imapreconnect(Imap *z)
143 {
144 	Sx *sx;
145 
146 	z->autoreconnect = 0;
147 	z->box = nil;
148 	z->inbox = nil;
149 
150 	if(z->fd >= 0){
151 		close(z->fd);
152 		z->fd = -1;
153 	}
154 
155 	if(chattyimap)
156 		fprint(2, "dial %s...\n", z->server);
157 	if((z->fd = ioimapdial(z->io, z->server, z->mode)) < 0)
158 		return -1;
159 	z->connected = 1;
160 	Binit(&z->b, z->fd, OREAD);
161 	if((sx = zBrdsx(z)) == nil){
162 		werrstr("no greeting");
163 		goto err;
164 	}
165 	if(chattyimap)
166 		fprint(2, "<I %#$\n", sx);
167 	if(sx->nsx >= 2 && isatom(sx->sx[0], "*") && isatom(sx->sx[1], "PREAUTH")){
168 		freesx(sx);
169 		goto preauth;
170 	}
171 	if(!oksx(sx)){
172 		werrstr("bad greeting - %#$", sx);
173 		goto err;
174 	}
175 	freesx(sx);
176 	sx = nil;
177 	if(imaplogin(z) < 0)
178 		goto err;
179 preauth:
180 	if(getboxes(z) < 0 || getbox(z, z->inbox) < 0)
181 		goto err;
182 	z->autoreconnect = 1;
183 	return 0;
184 
185 err:
186 	if(z->fd >= 0){
187 		close(z->fd);
188 		z->fd = -1;
189 	}
190 	if(sx)
191 		freesx(sx);
192 	z->autoreconnect = 1;
193 	z->connected = 0;
194 	return -1;
195 }
196 
197 static int
198 imaplogin(Imap *z)
199 {
200 	Sx *sx;
201 	UserPasswd *up;
202 
203 	if((up = auth_getuserpasswd(auth_getkey, "proto=pass role=client service=imap server=%q", z->server)) == nil){
204 		werrstr("getuserpasswd - %r");
205 		return -1;
206 	}
207 
208 	sx = imapcmdsx(z, nil, "LOGIN %Z %Z", up->user, up->passwd);
209 	freeup(up);
210 	if(sx == nil)
211 		return -1;
212 	if(!oksx(sx)){
213 		freesx(sx);
214 		werrstr("login rejected - %#$", sx);
215 		return -1;
216 	}
217 	return 0;
218 }
219 
220 static int
221 getboxes(Imap *z)
222 {
223 	int i;
224 	Box **r, **w, **e;
225 	
226 	for(i=0; i<nboxes; i++){
227 		boxes[i]->mark = 1;
228 		boxes[i]->exists = 0;
229 		boxes[i]->maxseen = 0;
230 	}
231 	if(imapcmd(z, nil, "LIST %Z *", z->root) < 0)
232 		return -1;
233 	if(z->root != nil && imapcmd(z, nil, "LIST %Z INBOX", "") < 0)
234 		return -1;
235 	if(z->nextbox && z->nextbox->mark)
236 		z->nextbox = nil;
237 	for(r=boxes, w=boxes, e=boxes+nboxes; r<e; r++){
238 		if((*r)->mark)
239 {fprint(2, "*** free box %s %s\n", (*r)->name, (*r)->imapname);
240 			boxfree(*r);
241 }
242 		else
243 			*w++ = *r;
244 	}
245 	nboxes = w - boxes;
246 	return 0;
247 }
248 
249 static int
250 getbox(Imap *z, Box *b)
251 {
252 	int i;
253 	Msg **r, **w, **e;
254 	
255 	if(b == nil)
256 		return 0;
257 	
258 	for(i=0; i<b->nmsg; i++)
259 		b->msg[i]->imapid = 0;
260 	if(imapcmd(z, b, "UID FETCH 1:* FLAGS") < 0)
261 		return -1;
262 	for(r=b->msg, w=b->msg, e=b->msg+b->nmsg; r<e; r++){
263 		if((*r)->imapid == 0)
264 			msgfree(*r);
265 		else{
266 			(*r)->ix = w-b->msg;
267 			*w++ = *r;
268 		}
269 	}
270 	b->nmsg = w - b->msg;
271 	b->imapinit = 1;
272 	checkbox(z, b);
273 	return 0;
274 }
275 
276 static void
277 freeup(UserPasswd *up)
278 {
279 	memset(up->user, 0, strlen(up->user));
280 	memset(up->passwd, 0, strlen(up->passwd));
281 	free(up);
282 }
283 
284 static void
285 imaptimerproc(void *v)
286 {
287 	Imap *z;
288 	
289 	z = v;
290 	for(;;){
291 		sleep(60*1000);
292 		qlock(z->r.l);
293 		rwakeup(&z->r);
294 		qunlock(z->r.l);
295 	}
296 }
297 
298 static void
299 checkbox(Imap *z, Box *b)
300 {
301 	if(imapcmd(z, b, "NOOP") >= 0){
302 		if(!b->imapinit)
303 			getbox(z, b);
304 		if(!b->imapinit)
305 			return;
306 		if(b==z->box && b->exists > b->maxseen){
307 			imapcmd(z, b, "UID FETCH %d:* FULL",
308 				b->uidnext);
309 		}
310 	}
311 }
312 
313 static void
314 imaprefreshthread(void *v)
315 {
316 	Imap *z;
317 	
318 	z = v;
319 	for(;;){
320 		qlock(z->r.l);
321 		rsleep(&z->r);
322 		qunlock(z->r.l);
323 		
324 		qlock(&z->lk);
325 		if(z->inbox)
326 			checkbox(z, z->inbox);
327 		qunlock(&z->lk);
328 	}
329 }
330 
331 /*
332  * Run a single command and return the Sx.  Does NOT redial.
333  */
334 static Sx*
335 imapvcmdsx0(Imap *z, char *fmt, va_list arg)
336 {
337 	char *s;
338 	Fmt f;
339 	int prefix, len;
340 	Sx *sx;
341 	
342 	if(canqlock(&z->lk))
343 		abort();
344 
345 	if(z->fd < 0 || !z->connected)
346 		return nil;
347 
348 	prefix = strlen(tag)+1;
349 	fmtstrinit(&f);
350 	fmtprint(&f, "%s ", tag);
351 	fmtvprint(&f, fmt, arg);
352 	fmtprint(&f, "\r\n");
353 	s = fmtstrflush(&f);
354 	len = strlen(s);
355 	s[len-2] = 0;
356 	if(chattyimap)
357 		fprint(2, "I> %s\n", s);
358 	s[len-2] = '\r';
359 	if(iowrite(z->io, z->fd, s, len) < 0){
360 		z->connected = 0;
361 		free(s);
362 		return nil;
363 	}
364 	sx = imapwaitsx(z);
365 	free(s);
366 	return sx;
367 }
368 
369 static Sx*
370 imapcmdsx0(Imap *z, char *fmt, ...)
371 {
372 	va_list arg;
373 	Sx *sx;
374 	
375 	va_start(arg, fmt);
376 	sx = imapvcmdsx0(z, fmt, arg);
377 	va_end(arg);
378 	return sx;
379 }
380 
381 /*
382  * Run a single command on box b.  Does redial.
383  */
384 static Sx*
385 imapvcmdsx(Imap *z, Box *b, char *fmt, va_list arg)
386 {
387 	int tries;
388 	Sx *sx;
389 	
390 	tries = 0;
391 	z->nextbox = b;
392 
393 	if(z->fd < 0 || !z->connected){
394 reconnect:
395 		if(!z->autoreconnect)
396 			return nil;
397 		if(imapreconnect(z) < 0)
398 			return nil;
399 		if(b && z->nextbox == nil)	/* box disappeared on reconnect */
400 			return nil;
401 	}
402 
403 	if(b && b != z->box){
404 		if(z->box)
405 			z->box->imapinit = 0;
406 		z->box = b;
407 		if((sx=imapcmdsx0(z, "SELECT %Z", b->imapname)) == nil){
408 			z->box = nil;
409 			if(tries++ == 0 && (z->fd < 0 || !z->connected))
410 				goto reconnect;
411 			return nil;
412 		}
413 		freesx(sx);
414 	}
415 
416 	if((sx=imapvcmdsx0(z, fmt, arg)) == nil){
417 		if(tries++ == 0 && (z->fd < 0 || !z->connected))
418 			goto reconnect;
419 		return nil;
420 	}
421 	return sx;
422 }
423 
424 static int
425 imapcmd(Imap *z, Box *b, char *fmt, ...)
426 {
427 	Sx *sx;
428 	va_list arg;
429 
430 	va_start(arg, fmt);
431 	sx = imapvcmdsx(z, b, fmt, arg);
432 	va_end(arg);
433 	if(sx == nil)
434 		return -1;
435 	if(sx->nsx < 2 || !isatom(sx->sx[1], "OK")){
436 		werrstr("%$", sx);
437 		freesx(sx);
438 		return -1;
439 	}
440 	freesx(sx);
441 	return 0;
442 }
443 
444 static Sx*
445 imapcmdsx(Imap *z, Box *b, char *fmt, ...)
446 {
447 	Sx *sx;
448 	va_list arg;
449 
450 	va_start(arg, fmt);
451 	sx = imapvcmdsx(z, b, fmt, arg);
452 	va_end(arg);
453 	return sx;
454 }
455 
456 static Sx*
457 imapwaitsx(Imap *z)
458 {
459 	Sx *sx;
460 	
461 	while((sx = zBrdsx(z)) != nil){
462 		if(chattyimap)
463 			fprint(2, "<| %#$\n", sx);
464 		if(sx->nsx >= 1 && sx->sx[0]->type == SxAtom && cistrcmp(sx->sx[0]->data, tag) == 0)
465 			return sx;
466 		if(sx->nsx >= 1 && sx->sx[0]->type == SxAtom && strcmp(sx->sx[0]->data, "*") == 0)
467 			unexpected(z, sx);
468 		if(sx->type == SxList && sx->nsx == 0){
469 			freesx(sx);
470 			break;
471 		}
472 		freesx(sx);
473 	}
474 	z->connected = 0;
475 	return nil;
476 }
477 
478 /*
479  * Imap interface to mail file system.
480  */
481 
482 static void
483 _bodyname(char *buf, char *ebuf, Part *p, char *extra)
484 {
485 	if(buf >= ebuf){
486 		fprint(2, "***** BUFFER TOO SMALL\n");
487 		return;
488 	}
489 	*buf = 0;
490 	if(p->parent){
491 		_bodyname(buf, ebuf, p->parent, "");
492 		buf += strlen(buf);
493 		seprint(buf, ebuf, ".%d", p->pix+1);
494 	}
495 	buf += strlen(buf);
496 	seprint(buf, ebuf, "%s", extra);
497 }
498 
499 static char*
500 bodyname(Part *p, char *extra)
501 {
502 	static char buf[256];
503 	memset(buf, 0, sizeof buf);	/* can't see why this is necessary, but it is */
504 	_bodyname(buf, buf+sizeof buf, p, extra);
505 	return buf+1;	/* buf[0] == '.' */
506 }
507 
508 static void
509 fetch1(Imap *z, Part *p, char *s)
510 {
511 	qlock(&z->lk);
512 	imapcmd(z, p->msg->box, "UID FETCH %d BODY[%s]", 
513 		p->msg->imapuid, bodyname(p, s));
514 	qunlock(&z->lk);
515 }
516 
517 void
518 imapfetchrawheader(Imap *z, Part *p)
519 {
520 	fetch1(z, p, ".HEADER");
521 }
522 
523 void
524 imapfetchrawmime(Imap *z, Part *p)
525 {
526 	fetch1(z, p, ".MIME");
527 }
528 
529 void
530 imapfetchrawbody(Imap *z, Part *p)
531 {
532 	fetch1(z, p, ".TEXT");
533 }
534 
535 void
536 imapfetchraw(Imap *z, Part *p)
537 {
538 	fetch1(z, p, "");
539 }
540 
541 static int
542 imaplistcmd(Imap *z, Box *box, char *before, Msg **m, uint nm, char *after)
543 {
544 	int i, r;
545 	char *cmd;
546 	Fmt fmt;
547 	
548 	if(nm == 0)
549 		return 0;
550 
551 	fmtstrinit(&fmt);
552 	fmtprint(&fmt, "%s ", before);
553 	for(i=0; i<nm; i++){
554 		if(i > 0)
555 			fmtrune(&fmt, ',');
556 		fmtprint(&fmt, "%ud", m[i]->imapuid);
557 	}
558 	fmtprint(&fmt, " %s", after);
559 	cmd = fmtstrflush(&fmt);
560 	
561 	r = 0;
562 	if(imapcmd(z, box, "%s", cmd) < 0)
563 		 r = -1;
564 	free(cmd);
565 	return r;
566 }
567 
568 int
569 imapcopylist(Imap *z, char *nbox, Msg **m, uint nm)
570 {
571 	int rv;
572 	char *name, *p;
573 	
574 	if(nm == 0)
575 		return 0;
576 
577 	qlock(&z->lk);
578 	if(strcmp(nbox, "mbox") == 0)
579 		name = estrdup("INBOX");
580 	else{
581 		p = esmprint("%s%s", z->root, nbox);
582 		name = esmprint("%Z", p);
583 		free(p);
584 	}
585 	rv = imaplistcmd(z, m[0]->box, "UID COPY", m, nm, name);
586 	free(name);
587 	qunlock(&z->lk);
588 	return rv;
589 }
590 
591 int
592 imapremovelist(Imap *z, Msg **m, uint nm)
593 {
594 	int rv;
595 	
596 	if(nm == 0)
597 		return 0;
598 
599 	qlock(&z->lk);
600 	rv = imaplistcmd(z, m[0]->box, "UID STORE", m, nm, "+FLAGS.SILENT (\\Deleted)");
601 	/* careful - box might be gone; use z->box instead */
602 	if(rv == 0 && z->box)
603 		rv = imapcmd(z, z->box, "EXPUNGE");
604 	qunlock(&z->lk);
605 	return rv;
606 }
607 
608 int
609 imapflaglist(Imap *z, int op, int flag, Msg **m, uint nm)
610 {
611 	char *mod, *s, *sep;
612 	int i, rv;
613 	Fmt fmt;
614 	
615 	if(op > 0)
616 		mod = "+";
617 	else if(op == 0)
618 		mod = "";
619 	else
620 		mod = "-";
621 
622 	fmtstrinit(&fmt);
623 	fmtprint(&fmt, "%sFLAGS (", mod);
624 	sep = "";
625 	for(i=0; i<nelem(flagstab); i++){
626 		if(flagstab[i].flag & flag){
627 			fmtprint(&fmt, "%s%s", sep, flagstab[i].name);
628 			sep = " ";
629 		}
630 	}
631 	fmtprint(&fmt, ")");
632 	s = fmtstrflush(&fmt);
633 	
634 	qlock(&z->lk);
635 	rv = imaplistcmd(z, m[0]->box, "UID STORE", m, nm, s);
636 	qunlock(&z->lk);
637 	free(s);
638 	return rv;
639 }
640 
641 int
642 imapsearchbox(Imap *z, Box *b, char *search, Msg ***mm)
643 {
644 	uint *uid;
645 	int i, nuid;
646 	Msg **m;
647 	int nm;
648 
649 	qlock(&z->lk);
650 	if(imapcmd(z, b, "UID SEARCH CHARSET UTF-8 TEXT %Z", search) < 0){
651 		qunlock(&z->lk);
652 		return -1;
653 	}
654 
655 	uid = z->uid;
656 	nuid = z->nuid;
657 	z->uid = nil;
658 	z->nuid = 0;
659 	qunlock(&z->lk);
660 
661 	m = emalloc(nuid*sizeof m[0]);
662 	nm = 0;
663 	for(i=0; i<nuid; i++)
664 		if((m[nm] = msgbyimapuid(b, uid[i], 0)) != nil)
665 			nm++;
666 	*mm = m;
667 	free(uid);
668 	return nm;
669 }
670 
671 void
672 imapcheckbox(Imap *z, Box *b)
673 {
674 	if(b == nil)
675 		return;
676 	qlock(&z->lk);
677 	checkbox(z, b);
678 	qunlock(&z->lk);
679 }
680 
681 /*
682  * Imap utility routines
683  */
684 static long
685 _ioimapdial(va_list *arg)
686 {
687 	char *server;
688 	int mode;
689 	
690 	server = va_arg(*arg, char*);
691 	mode = va_arg(*arg, int);
692 	return imapdial(server, mode);
693 }
694 static int
695 ioimapdial(Ioproc *io, char *server, int mode)
696 {
697 	return iocall(io, _ioimapdial, server, mode);
698 }
699 
700 static long
701 _ioBrdsx(va_list *arg)
702 {
703 	Biobuf *b;
704 	Sx **sx;
705 	
706 	b = va_arg(*arg, Biobuf*);
707 	sx = va_arg(*arg, Sx**);
708 	*sx = Brdsx(b);
709 	if((*sx) && (*sx)->type == SxList && (*sx)->nsx == 0){
710 		freesx(*sx);
711 		*sx = nil;
712 	}
713 	return 0;
714 }
715 static Sx*
716 ioBrdsx(Ioproc *io, Biobuf *b)
717 {
718 	Sx *sx;
719 
720 	iocall(io, _ioBrdsx, b, &sx);
721 	return sx;
722 }
723 
724 static Sx*
725 zBrdsx(Imap *z)
726 {
727 	if(z->ticks && --z->ticks==0){
728 		close(z->fd);
729 		z->fd = -1;
730 		return nil;
731 	}
732 	return ioBrdsx(z->io, &z->b);
733 }
734 
735 static int
736 imapdial(char *server, int mode)
737 {
738 	int p[2];
739 	int fd[3];
740 	char *tmp;
741 	
742 	switch(mode){
743 	default:
744 	case Unencrypted:
745 		return dial(netmkaddr(server, "tcp", "143"), nil, nil, nil);
746 		
747 	case Starttls:
748 		werrstr("starttls not supported");
749 		return -1;
750 
751 	case Tls:
752 		if(pipe(p) < 0)
753 			return -1;
754 		fd[0] = dup(p[0], -1);
755 		fd[1] = dup(p[0], -1);
756 		fd[2] = dup(2, -1);
757 		tmp = esmprint("%s:993", server);
758 		if(threadspawnl(fd, "/usr/sbin/stunnel", "stunnel", "-c", "-r", tmp, nil) < 0
759 		    && threadspawnl(fd, "/usr/bin/stunnel", "stunnel", "-c", "-r", tmp, nil) < 0){
760 			free(tmp);
761 			close(p[0]);
762 			close(p[1]);
763 			close(fd[0]);
764 			close(fd[1]);
765 			close(fd[2]);
766 			return -1;
767 		}
768 		free(tmp);
769 		close(p[0]);
770 		return p[1];
771 	
772 	case Cmd:
773 		if(pipe(p) < 0)
774 			return -1;
775 		fd[0] = dup(p[0], -1);
776 		fd[1] = dup(p[0], -1);
777 		fd[2] = dup(2, -1);
778 		if(threadspawnl(fd, "/usr/local/plan9/bin/rc", "rc", "-c", server, nil) < 0){
779 			close(p[0]);
780 			close(p[1]);
781 			close(fd[0]);
782 			close(fd[1]);
783 			close(fd[2]);
784 			return -1;
785 		}
786 		close(p[0]);
787 		return p[1];
788 	}
789 }
790 
791 enum
792 {
793 	Qok = 0,
794 	Qquote,
795 	Qbackslash
796 };
797 
798 static int
799 needtoquote(Rune r)
800 {
801 	if(r >= Runeself)
802 		return Qquote;
803 	if(r <= ' ')
804 		return Qquote;
805 	if(r=='\\' || r=='"')
806 		return Qbackslash;
807 	return Qok;
808 }
809 
810 static int
811 imapquote(Fmt *f)
812 {
813 	char *s, *t;
814 	int w, quotes;
815 	Rune r;
816 
817 	s = va_arg(f->args, char*);
818 	if(s == nil || *s == '\0')
819 		return fmtstrcpy(f, "\"\"");
820 
821 	quotes = 0;
822 	if(f->flags&FmtSharp)
823 		quotes = 1;
824 	for(t=s; *t; t+=w){
825 		w = chartorune(&r, t);
826 		quotes |= needtoquote(r);
827 	}
828 	if(quotes == 0)
829 		return fmtstrcpy(f, s);
830 
831 	fmtrune(f, '"');
832 	for(t=s; *t; t+=w){
833 		w = chartorune(&r, t);
834 		if(needtoquote(r) == Qbackslash)
835 			fmtrune(f, '\\');
836 		fmtrune(f, r);
837 	}
838 	return fmtrune(f, '"');
839 }
840 
841 static int
842 fmttype(char c)
843 {
844 	switch(c){
845 	case 'A':
846 		return SxAtom;
847 	case 'L':
848 		return SxList;
849 	case 'N':
850 		return SxNumber;
851 	case 'S':
852 		return SxString;
853 	default:
854 		return -1;
855 	}
856 }
857 
858 /*
859  * Check S expression against format string.
860  */
861 static int
862 sxmatch(Sx *sx, char *fmt)
863 {
864 	int i;
865 	
866 	for(i=0; fmt[i]; i++){
867 		if(fmt[i] == '*')
868 			fmt--;	/* like i-- but better */
869 		if(i == sx->nsx && fmt[i+1] == '*')
870 			return 1;
871 		if(i >= sx->nsx)
872 			return 0;
873 		if(sx->sx[i] == nil)
874 			return 0;
875 		if(sx->sx[i]->type == SxAtom && strcmp(sx->sx[i]->data, "NIL") == 0){
876 			if(fmt[i] == 'L'){
877 				free(sx->sx[i]->data);
878 				sx->sx[i]->data = nil;
879 				sx->sx[i]->type = SxList;
880 				sx->sx[i]->sx = nil;
881 				sx->sx[i]->nsx = 0;
882 			}
883 			else if(fmt[i] == 'S'){
884 				free(sx->sx[i]->data);
885 				sx->sx[i]->data = nil;
886 				sx->sx[i]->type = SxString;
887 			}
888 		}
889 		if(sx->sx[i]->type == SxAtom && fmt[i]=='S')
890 			sx->sx[i]->type = SxString;
891 		if(sx->sx[i]->type != fmttype(fmt[i])){
892 			fprint(2, "sxmatch: %$ not %c\n", sx->sx[i], fmt[i]);
893 			return 0;
894 		}
895 	}
896 	if(i != sx->nsx)
897 		return 0;
898 	return 1;
899 }
900 
901 /*
902  * Check string against format string.
903  */
904 static int
905 stringmatch(char *fmt, char *s)
906 {
907 	for(; *fmt && *s; fmt++, s++){
908 		switch(*fmt){
909 		case '0':
910 			if(*s == ' ')
911 				break;
912 			/* fall through */
913 		case '1':
914 			if(*s < '0' || *s > '9')
915 				return 0;
916 			break;
917 		case 'A':
918 			if(*s < 'A' || *s > 'Z')
919 				return 0;
920 			break;
921 		case 'a':
922 			if(*s < 'a' || *s > 'z')
923 				return 0;
924 			break;
925 		case '+':
926 			if(*s != '-' && *s != '+')
927 				return 0;
928 			break;
929 		default:
930 			if(*s != *fmt)
931 				return 0;
932 			break;
933 		}
934 	}
935 	if(*fmt || *s)
936 		return 0;
937 	return 1;
938 }
939 
940 /*
941  * Parse simple S expressions and IMAP elements.
942  */
943 static int
944 isatom(Sx *v, char *name)
945 {
946 	int n;
947 	
948 	if(v == nil || v->type != SxAtom)
949 		return 0;
950 	n = strlen(name);
951 	if(cistrncmp(v->data, name, n) == 0)
952 		if(v->data[n] == 0 || (n>0 && v->data[n-1] == '['))
953 			return 1;
954 	return 0;
955 }
956 
957 static int
958 isstring(Sx *sx)
959 {
960 	if(sx->type == SxAtom)
961 		sx->type = SxString;
962 	return sx->type == SxString;
963 }
964 
965 static int
966 isnumber(Sx *sx)
967 {
968 	return sx->type == SxNumber;
969 }
970 
971 static int
972 isnil(Sx *v)
973 {
974 	return v == nil || 
975 		(v->type==SxList && v->nsx == 0) ||
976 		(v->type==SxAtom && strcmp(v->data, "NIL") == 0);
977 }
978 
979 static int
980 islist(Sx *v)
981 {
982 	return isnil(v) || v->type==SxList;
983 }
984 
985 static uint
986 parseflags(Sx *v)
987 {
988 	int f, i, j;
989 	
990 	if(v->type != SxList){
991 		warn("malformed flags: %$", v);
992 		return 0;
993 	}
994 	f = 0;
995 	for(i=0; i<v->nsx; i++){
996 		if(v->sx[i]->type != SxAtom)
997 			continue;
998 		for(j=0; j<nelem(flagstab); j++)
999 			if(cistrcmp(v->sx[i]->data, flagstab[j].name) == 0)
1000 				f |= flagstab[j].flag;
1001 	}
1002 	return f;
1003 }
1004 	
1005 static char months[] = "JanFebMarAprMayJunJulAugSepOctNovDec";
1006 static int
1007 parsemon(char *s)
1008 {
1009 	int i;
1010 	
1011 	for(i=0; months[i]; i+=3)
1012 		if(memcmp(s, months+i, 3) == 0)
1013 			return i/3;
1014 	return -1;
1015 }
1016 
1017 static uint
1018 parsedate(Sx *v)
1019 {
1020 	Tm tm;
1021 	uint t;
1022 	int delta;
1023 	char *p;
1024 	
1025 	if(v->type != SxString || !stringmatch("01-Aaa-1111 01:11:11 +1111", v->data)){
1026 	bad:
1027 		warn("bad date: %$", v);
1028 		return 0;
1029 	}
1030 	
1031 	/* cannot use atoi because 09 is malformed octal! */
1032 	memset(&tm, 0, sizeof tm);
1033 	p = v->data;
1034 	tm.mday = strtol(p, 0, 10);
1035 	tm.mon = parsemon(p+3);
1036 	if(tm.mon == -1)
1037 		goto bad;
1038 	tm.year = strtol(p+7, 0, 10) - 1900;
1039 	tm.hour = strtol(p+12, 0, 10);
1040 	tm.min = strtol(p+15, 0, 10);
1041 	tm.sec = strtol(p+18, 0, 10);
1042 	strcpy(tm.zone, "GMT");
1043 
1044 	t = tm2sec(&tm);
1045 	delta = ((p[22]-'0')*10+p[23]-'0')*3600 + ((p[24]-'0')*10+p[25]-'0')*60;
1046 	if(p[21] == '-')
1047 		delta = -delta;
1048 	
1049 	t -= delta;
1050 	return t;
1051 }
1052 
1053 static uint
1054 parsenumber(Sx *v)
1055 {
1056 	if(v->type != SxNumber)
1057 		return 0;
1058 	return v->number;
1059 }
1060 
1061 static void
1062 hash(DigestState *ds, char *tag, char *val)
1063 {
1064 	if(val == nil)
1065 		val = "";
1066 	md5((uchar*)tag, strlen(tag)+1, nil, ds);
1067 	md5((uchar*)val, strlen(val)+1, nil, ds);
1068 }
1069 
1070 static Hdr*
1071 parseenvelope(Sx *v)
1072 {
1073 	Hdr *hdr;
1074 	uchar digest[16];
1075 	DigestState ds;
1076 	
1077 	if(v->type != SxList || !sxmatch(v, "SSLLLLLLSS")){
1078 		warn("bad envelope: %$", v);
1079 		return nil;
1080 	}
1081 
1082 	hdr = emalloc(sizeof *hdr);
1083 	hdr->date = nstring(v->sx[0]);
1084 	hdr->subject = unrfc2047(nstring(v->sx[1]));
1085 	hdr->from = copyaddrs(v->sx[2]);
1086 	hdr->sender = copyaddrs(v->sx[3]);
1087 	hdr->replyto = copyaddrs(v->sx[4]);
1088 	hdr->to = copyaddrs(v->sx[5]);
1089 	hdr->cc = copyaddrs(v->sx[6]);
1090 	hdr->bcc = copyaddrs(v->sx[7]);
1091 	hdr->inreplyto = unrfc2047(nstring(v->sx[8]));
1092 	hdr->messageid = unrfc2047(nstring(v->sx[9]));
1093 	
1094 	memset(&ds, 0, sizeof ds);
1095 	hash(&ds, "date", hdr->date);
1096 	hash(&ds, "subject", hdr->subject);
1097 	hash(&ds, "from", hdr->from);
1098 	hash(&ds, "sender", hdr->sender);
1099 	hash(&ds, "replyto", hdr->replyto);
1100 	hash(&ds, "to", hdr->to);
1101 	hash(&ds, "cc", hdr->cc);
1102 	hash(&ds, "bcc", hdr->bcc);
1103 	hash(&ds, "inreplyto", hdr->inreplyto);
1104 	hash(&ds, "messageid", hdr->messageid);
1105 	md5(0, 0, digest, &ds);
1106 	hdr->digest = esmprint("%.16H", digest);
1107 
1108 	return hdr;
1109 }
1110 
1111 static void
1112 strlwr(char *s)
1113 {
1114 	char *t;
1115 	
1116 	if(s == nil)
1117 		return;
1118 	for(t=s; *t; t++)
1119 		if('A' <= *t && *t <= 'Z')
1120 			*t += 'a' - 'A';
1121 }
1122 
1123 static void
1124 nocr(char *s)
1125 {
1126 	char *r, *w;
1127 	
1128 	if(s == nil)
1129 		return;
1130 	for(r=w=s; *r; r++)
1131 		if(*r != '\r')
1132 			*w++ = *r;
1133 	*w = 0;
1134 }
1135 
1136 /*
1137  * substitute all occurrences of a with b in s.
1138  */
1139 static char*
1140 gsub(char *s, char *a, char *b)
1141 {
1142 	char *p, *t, *w, *last;
1143 	int n;
1144 	
1145 	n = 0;
1146 	for(p=s; (p=strstr(p, a)) != nil; p+=strlen(a))
1147 		n++;
1148 	if(n == 0)
1149 		return s;
1150 	t = emalloc(strlen(s)+n*strlen(b)+1);
1151 	w = t;
1152 	for(p=s; last=p, (p=strstr(p, a)) != nil; p+=strlen(a)){
1153 		memmove(w, last, p-last);
1154 		w += p-last;
1155 		memmove(w, b, strlen(b));
1156 		w += strlen(b);
1157 	}
1158 	strcpy(w, last);
1159 	free(s);
1160 	return t;
1161 }
1162 
1163 /*
1164  * Table-driven IMAP "unexpected response" parser.
1165  * All the interesting data is in the unexpected responses.
1166  */
1167 static void xlist(Imap*, Sx*);
1168 static void xrecent(Imap*, Sx*);
1169 static void xexists(Imap*, Sx*);
1170 static void xok(Imap*, Sx*);
1171 static void xflags(Imap*, Sx*);
1172 static void xfetch(Imap*, Sx*);
1173 static void xexpunge(Imap*, Sx*);
1174 static void xbye(Imap*, Sx*);
1175 static void xsearch(Imap*, Sx*);
1176 
1177 static struct {
1178 	int		num;
1179 	char		*name;
1180 	char		*fmt;
1181 	void		(*fn)(Imap*, Sx*);
1182 } unextab[] = {
1183 	0,	"BYE",		nil,			xbye,
1184 	0,	"FLAGS",		"AAL",		xflags,
1185 	0,	"LIST",		"AALSS",		xlist,
1186 	0,	"OK",		nil,			xok,
1187 	0,	"SEARCH",	"AAN*",		xsearch,
1188 
1189 	1,	"EXISTS",		"ANA",		xexists,
1190 	1,	"EXPUNGE",	"ANA",		xexpunge,
1191 	1,	"FETCH",		"ANAL",		xfetch,
1192 	1,	"RECENT",	"ANA",		xrecent
1193 };
1194 
1195 static void
1196 unexpected(Imap *z, Sx *sx)
1197 {
1198 	int i, num;
1199 	char *name;
1200 
1201 	if(sx->nsx >= 3 && sx->sx[1]->type == SxNumber && sx->sx[2]->type == SxAtom){
1202 		num = 1;
1203 		name = sx->sx[2]->data;
1204 	}else if(sx->nsx >= 2 && sx->sx[1]->type == SxAtom){
1205 		num = 0;
1206 		name = sx->sx[1]->data;
1207 	}else
1208 		return;
1209 	
1210 	for(i=0; i<nelem(unextab); i++){
1211 		if(unextab[i].num == num && cistrcmp(unextab[i].name, name) == 0){
1212 			if(unextab[i].fmt && !sxmatch(sx, unextab[i].fmt)){
1213 				warn("malformed %s: %$", name, sx);
1214 				continue;
1215 			}
1216 			unextab[i].fn(z, sx);
1217 		}
1218 	}
1219 }
1220 
1221 static int
1222 alldollars(char *s)
1223 {
1224 	for(; *s; s++)
1225 		if(*s != '$')
1226 			return 0;
1227 	return 1;
1228 }
1229 
1230 static void
1231 xlist(Imap *z, Sx *sx)
1232 {
1233 	int inbox;
1234 	char *s, *t;
1235 	Box *box;
1236 
1237 	s = estrdup(sx->sx[4]->data);
1238 	if(sx->sx[3]->data && strcmp(sx->sx[3]->data, "/") != 0){
1239 		s = gsub(s, "/", "_");
1240 		s = gsub(s, sx->sx[3]->data, "/");
1241 	}
1242 
1243 	/*
1244 	 * INBOX is the special imap name for the main mailbox.
1245 	 * All other mailbox names have the root prefix removed, if applicable.
1246 	 */
1247 	inbox = 0;
1248 	if(cistrcmp(s, "INBOX") == 0){
1249 		inbox = 1;
1250 		free(s);
1251 		s = estrdup("mbox");
1252 	} else if(z->root && strstr(s, z->root) == s) {
1253 		t = estrdup(s+strlen(z->root));
1254 		free(s);
1255 		s = t;
1256 	}
1257 	
1258 	/* 
1259 	 * Plan 9 calls the main mailbox mbox.  
1260 	 * Rename any existing mbox by appending a $.
1261 	 */
1262 	if(!inbox && strncmp(s, "mbox", 4) == 0 && alldollars(s+4)){
1263 		t = emalloc(strlen(s)+2);
1264 		strcpy(t, s);
1265 		strcat(t, "$");
1266 		free(s);
1267 		s = t;
1268 	}
1269 
1270 	box = boxcreate(s);
1271 	if(box == nil)
1272 		return;
1273 	box->imapname = estrdup(sx->sx[4]->data);
1274 	if(inbox)
1275 		z->inbox = box;
1276 	box->mark = 0;
1277 	box->flags = parseflags(sx->sx[2]);
1278 }
1279 
1280 static void
1281 xrecent(Imap *z, Sx *sx)
1282 {
1283 	if(z->box)
1284 		z->box->recent = sx->sx[1]->number;
1285 }
1286 
1287 static void
1288 xexists(Imap *z, Sx *sx)
1289 {
1290 	if(z->box){
1291 		z->box->exists = sx->sx[1]->number;
1292 		if(z->box->exists < z->box->maxseen)
1293 			z->box->maxseen = z->box->exists;
1294 	}
1295 }
1296 
1297 static void
1298 xflags(Imap *z, Sx *sx)
1299 {
1300 	/*
1301 	 * This response contains in sx->sx[2] the list of flags
1302 	 * that can be validly attached to messages in z->box.
1303 	 * We don't have any use for this list, since we 
1304 	 * use only the standard flags.
1305 	 */
1306 }
1307 
1308 static void
1309 xbye(Imap *z, Sx *sx)
1310 {
1311 	close(z->fd);
1312 	z->fd = -1;
1313 	z->connected = 0;
1314 }
1315 
1316 static void
1317 xexpunge(Imap *z, Sx *sx)
1318 {
1319 	int i, n;
1320 	Box *b;
1321 
1322 	if((b=z->box) == nil)
1323 		return;
1324 	n = sx->sx[1]->number;
1325 	for(i=0; i<b->nmsg; i++){
1326 		if(b->msg[i]->imapid == n){
1327 			msgplumb(b->msg[i], 1);
1328 			msgfree(b->msg[i]);
1329 			b->nmsg--;
1330 			memmove(b->msg+i, b->msg+i+1, (b->nmsg-i)*sizeof b->msg[0]);
1331 			i--;
1332 			b->maxseen--;
1333 			b->exists--;
1334 			continue;
1335 		}
1336 		if(b->msg[i]->imapid > n)
1337 			b->msg[i]->imapid--;
1338 		b->msg[i]->ix = i;
1339 	}
1340 }
1341 
1342 static void
1343 xsearch(Imap *z, Sx *sx)
1344 {
1345 	int i;
1346 	
1347 	free(z->uid);
1348 	z->uid = emalloc((sx->nsx-2)*sizeof z->uid[0]);
1349 	z->nuid = sx->nsx-2;
1350 	for(i=0; i<z->nuid; i++)
1351 		z->uid[i] = sx->sx[i+2]->number;
1352 }
1353 
1354 /* 
1355  * Table-driven FETCH message info parser.
1356  */
1357 static void xmsgflags(Msg*, Sx*, Sx*);
1358 static void xmsgdate(Msg*, Sx*, Sx*);
1359 static void xmsgrfc822size(Msg*, Sx*, Sx*);
1360 static void xmsgenvelope(Msg*, Sx*, Sx*);
1361 static void xmsgbody(Msg*, Sx*, Sx*);
1362 static void xmsgbodydata(Msg*, Sx*, Sx*);
1363 
1364 static struct {
1365 	char *name;
1366 	void (*fn)(Msg*, Sx*, Sx*);
1367 } msgtab[] = {
1368 	"FLAGS", xmsgflags,
1369 	"INTERNALDATE", xmsgdate,
1370 	"RFC822.SIZE", xmsgrfc822size,
1371 	"ENVELOPE", xmsgenvelope,
1372 	"BODY", xmsgbody,
1373 	"BODY[", xmsgbodydata
1374 };
1375 
1376 static void
1377 xfetch(Imap *z, Sx *sx)
1378 {
1379 	int i, j, n, uid;
1380 	Msg *msg;
1381 
1382 	if(z->box == nil){
1383 		warn("FETCH but no open box: %$", sx);
1384 		return;
1385 	}
1386 
1387 	/* * 152 FETCH (UID 185 FLAGS () ...) */
1388 	if(sx->sx[3]->nsx%2){
1389 		warn("malformed FETCH: %$", sx);
1390 		return;
1391 	}
1392 
1393 	n = sx->sx[1]->number;
1394 	sx = sx->sx[3];
1395 	for(i=0; i<sx->nsx; i+=2){
1396 		if(isatom(sx->sx[i], "UID")){
1397 			if(sx->sx[i+1]->type == SxNumber){
1398 				uid = sx->sx[i+1]->number;
1399 				goto haveuid;
1400 			}
1401 		}
1402 	}
1403 /* This happens: too bad.
1404 	warn("FETCH without UID: %$", sx);
1405 */
1406 	return;
1407 
1408 haveuid:
1409 	msg = msgbyimapuid(z->box, uid, 1);
1410 	if(msg->imapid && msg->imapid != n)
1411 		warn("msg id mismatch: want %d have %d", msg->id, n);
1412 	msg->imapid = n;
1413 	for(i=0; i<sx->nsx; i+=2){
1414 		for(j=0; j<nelem(msgtab); j++)
1415 			if(isatom(sx->sx[i], msgtab[j].name))
1416 				msgtab[j].fn(msg, sx->sx[i], sx->sx[i+1]);
1417 	}
1418 }
1419 
1420 static void
1421 xmsgflags(Msg *msg, Sx *k, Sx *v)
1422 {
1423 	USED(k);
1424 	msg->flags = parseflags(v);
1425 }
1426 
1427 static void
1428 xmsgdate(Msg *msg, Sx *k, Sx *v)
1429 {
1430 	USED(k);
1431 	msg->date = parsedate(v);
1432 }
1433 
1434 static void
1435 xmsgrfc822size(Msg *msg, Sx *k, Sx *v)
1436 {
1437 	USED(k);
1438 	msg->size = parsenumber(v);
1439 }
1440 
1441 static char*
1442 nstring(Sx *v)
1443 {
1444 	char *p;
1445 	
1446 	if(isnil(v))
1447 		return estrdup("");
1448 	p = v->data;
1449 	v->data = nil;
1450 	return p;
1451 }
1452 
1453 static char*
1454 copyaddrs(Sx *v)
1455 {
1456 	char *s, *sep;
1457 	char *name, *email, *host, *mbox;
1458 	int i;
1459 	Fmt fmt;
1460 	
1461 	if(v->nsx == 0)
1462 		return nil;
1463 
1464 	fmtstrinit(&fmt);
1465 	sep = "";
1466 	for(i=0; i<v->nsx; i++){
1467 		if(!sxmatch(v->sx[i], "SSSS"))
1468 			warn("bad address: %$", v->sx[i]);
1469 		name = unrfc2047(nstring(v->sx[i]->sx[0]));
1470 		/* ignore sx[1] - route */
1471 		mbox = unrfc2047(nstring(v->sx[i]->sx[2]));
1472 		host = unrfc2047(nstring(v->sx[i]->sx[3]));
1473 		if(mbox == nil || host == nil){	/* rfc822 group syntax */
1474 			free(name);
1475 			free(mbox);
1476 			free(host);
1477 			continue;
1478 		}
1479 		email = esmprint("%s@%s", mbox, host);
1480 		free(mbox);
1481 		free(host);
1482 		fmtprint(&fmt, "%s%q %q", sep, name ? name : "", email ? email : "");
1483 		free(name);
1484 		free(email);
1485 		sep = " ";
1486 	}
1487 	s = fmtstrflush(&fmt);
1488 	if(s == nil)
1489 		sysfatal("out of memory");
1490 	return s;
1491 }
1492 
1493 static void
1494 xmsgenvelope(Msg *msg, Sx *k, Sx *v)
1495 {
1496 	hdrfree(msg->part[0]->hdr);
1497 	msg->part[0]->hdr = parseenvelope(v);
1498 }
1499 
1500 static struct {
1501 	char *name;
1502 	int offset;
1503 } paramtab[] = {
1504 	"charset",	offsetof(Part, charset),
1505 	"name",		offsetof(Part, filename)
1506 };
1507 
1508 static void
1509 parseparams(Part *part, Sx *v)
1510 {
1511 	int i, j;
1512 	char *s, *t, **p;
1513 	
1514 	if(isnil(v))
1515 		return;
1516 	if(v->nsx%2){
1517 		warn("bad message params: %$", v);
1518 		return;
1519 	}
1520 	for(i=0; i<v->nsx; i+=2){
1521 		s = nstring(v->sx[i]);
1522 		t = nstring(v->sx[i+1]);
1523 		for(j=0; j<nelem(paramtab); j++){
1524 			if(cistrcmp(paramtab[j].name, s) == 0){
1525 				p = (char**)((char*)part+paramtab[j].offset);
1526 				free(*p);
1527 				*p = t;
1528 				t = nil;
1529 				break;
1530 			}
1531 		}
1532 		free(s);
1533 		free(t);
1534 	}			
1535 }
1536 
1537 static void
1538 parsestructure(Part *part, Sx *v)
1539 {
1540 	int i;
1541 	char *s, *t;
1542 	
1543 	if(isnil(v))
1544 		return;
1545 	if(v->type != SxList){
1546 	bad:
1547 		warn("bad structure: %$", v);
1548 		return;
1549 	}
1550 	if(islist(v->sx[0])){
1551 		/* multipart */
1552 		for(i=0; i<v->nsx && islist(v->sx[i]); i++)
1553 			parsestructure(partcreate(part->msg, part), v->sx[i]);
1554 		free(part->type);
1555 		if(i != v->nsx-1 || !isstring(v->sx[i])){
1556 			warn("bad multipart structure: %$", v);
1557 			part->type = estrdup("multipart/mixed");
1558 			return;
1559 		}
1560 		s = nstring(v->sx[i]);
1561 		strlwr(s);
1562 		part->type = esmprint("multipart/%s", s);
1563 		free(s);
1564 		return;
1565 	}
1566 	/* single part */
1567 	if(!isstring(v->sx[0]) || v->nsx < 2)
1568 		goto bad;
1569 	s = nstring(v->sx[0]);
1570 	t = nstring(v->sx[1]);
1571 	strlwr(s);
1572 	strlwr(t);
1573 	free(part->type);
1574 	part->type = esmprint("%s/%s", s, t);
1575 	if(v->nsx < 7 || !islist(v->sx[2]) || !isstring(v->sx[3]) 
1576 	|| !isstring(v->sx[4]) || !isstring(v->sx[5]) || !isnumber(v->sx[6]))
1577 		goto bad;
1578 	parseparams(part, v->sx[2]);
1579 	part->idstr = nstring(v->sx[3]);
1580 	part->desc = nstring(v->sx[4]);
1581 	part->encoding = nstring(v->sx[5]);
1582 	part->size = v->sx[6]->number;
1583 	if(strcmp(s, "message") == 0 && strcmp(t, "rfc822") == 0){
1584 		if(v->nsx < 10 || !islist(v->sx[7]) || !islist(v->sx[8]) || !isnumber(v->sx[9]))
1585 			goto bad;
1586 		part->hdr = parseenvelope(v->sx[7]);
1587 		parsestructure(partcreate(part->msg, part), v->sx[8]);
1588 		part->lines = v->sx[9]->number;
1589 	}
1590 	if(strcmp(s, "text") == 0){
1591 		if(v->nsx < 8 || !isnumber(v->sx[7]))
1592 			goto bad;
1593 		part->lines = v->sx[7]->number;
1594 	}
1595 }
1596 
1597 static void
1598 xmsgbody(Msg *msg, Sx *k, Sx *v)
1599 {
1600 	if(v->type != SxList){
1601 		warn("bad body: %$", v);
1602 		return;
1603 	}
1604 	/*
1605 	 * To follow the structure exactly we should
1606 	 * be doing this to partcreate(msg, msg->part[0]),
1607 	 * and we should leave msg->part[0] with type message/rfc822,
1608 	 * but the extra layer is redundant - what else would be in a mailbox?
1609 	 */
1610 	parsestructure(msg->part[0], v);
1611 	if(msg->box->maxseen < msg->imapid)
1612 		msg->box->maxseen = msg->imapid;
1613 	if(msg->imapuid >= msg->box->uidnext)
1614 		msg->box->uidnext = msg->imapuid+1;
1615 	msgplumb(msg, 0);
1616 }
1617 
1618 static void
1619 xmsgbodydata(Msg *msg, Sx *k, Sx *v)
1620 {
1621 	int i;
1622 	char *name, *p;
1623 	Part *part;
1624 	
1625 	name = k->data;
1626 	name += 5;	/* body[ */
1627 	p = strchr(name, ']');
1628 	if(p)
1629 		*p = 0;
1630 	
1631 	/* now name is something like 1 or 3.2.MIME - walk down parts from root */
1632 	part = msg->part[0];
1633 
1634 
1635 	while('1' <= name[0] && name[0] <= '9'){
1636 		i = strtol(name, &p, 10);
1637 		if(*p == '.')
1638 			p++;
1639 		else if(*p != 0){
1640 			warn("bad body name: %$", k);
1641 			return;
1642 		}
1643 		if((part = subpart(part, i-1)) == nil){
1644 			warn("unknown body part: %$", k);
1645 			return;
1646 		}
1647 		name = p;
1648 	}
1649 
1650 
1651 	if(cistrcmp(name, "") == 0){
1652 		free(part->raw);
1653 		part->raw = nstring(v);
1654 		nocr(part->raw);
1655 	}else if(cistrcmp(name, "HEADER") == 0){
1656 		free(part->rawheader);
1657 		part->rawheader = nstring(v);
1658 		nocr(part->rawheader);
1659 	}else if(cistrcmp(name, "MIME") == 0){
1660 		free(part->mimeheader);
1661 		part->mimeheader = nstring(v);
1662 		nocr(part->mimeheader);
1663 	}else if(cistrcmp(name, "TEXT") == 0){
1664 		free(part->rawbody);
1665 		part->rawbody = nstring(v);
1666 		nocr(part->rawbody);
1667 	}
1668 }
1669 
1670 /*
1671  * Table-driven OK info parser.
1672  */
1673 static void xokuidvalidity(Imap*, Sx*);
1674 static void xokpermflags(Imap*, Sx*);
1675 static void xokunseen(Imap*, Sx*);
1676 static void xokreadwrite(Imap*, Sx*);
1677 static void xokreadonly(Imap*, Sx*);
1678 
1679 struct {
1680 	char *name;
1681 	char fmt;
1682 	void (*fn)(Imap*, Sx*);
1683 } oktab[] = {
1684 	"UIDVALIDITY", 'N',	xokuidvalidity,
1685 	"PERMANENTFLAGS", 'L',	xokpermflags,
1686 	"UNSEEN", 'N',	xokunseen,
1687 	"READ-WRITE", 0,	xokreadwrite,
1688 	"READ-ONLY",	0, xokreadonly
1689 };
1690 
1691 static void
1692 xok(Imap *z, Sx *sx)
1693 {
1694 	int i;
1695 	char *name;
1696 	Sx *arg;
1697 
1698 	if(sx->nsx >= 4 && sx->sx[2]->type == SxAtom && sx->sx[2]->data[0] == '['){
1699 		if(sx->sx[3]->type == SxAtom && sx->sx[3]->data[0] == ']')
1700 			arg = nil;
1701 		else if(sx->sx[4]->type == SxAtom && sx->sx[4]->data[0] == ']')
1702 			arg = sx->sx[3];
1703 		else{
1704 			warn("cannot parse OK: %$", sx);
1705 			return;
1706 		}
1707 		name = sx->sx[2]->data+1;
1708 		for(i=0; i<nelem(oktab); i++){
1709 			if(cistrcmp(name, oktab[i].name) == 0){
1710 				if(oktab[i].fmt && (arg==nil || arg->type != fmttype(oktab[i].fmt))){
1711 					warn("malformed %s: %$", name, arg);
1712 					continue;
1713 				}
1714 				oktab[i].fn(z, arg);
1715 			}
1716 		}
1717 	}
1718 }
1719 
1720 static void
1721 xokuidvalidity(Imap *z, Sx *sx)
1722 {
1723 	int i;
1724 	Box *b;
1725 	
1726 	if((b=z->box) == nil)
1727 		return;
1728 	if(b->validity != sx->number){
1729 		b->validity = sx->number;
1730 		b->uidnext = 1;
1731 		for(i=0; i<b->nmsg; i++)
1732 			msgfree(b->msg[i]);
1733 		free(b->msg);
1734 		b->msg = nil;
1735 		b->nmsg = 0;
1736 	}
1737 }
1738 
1739 static void
1740 xokpermflags(Imap *z, Sx *sx)
1741 {
1742 /*	z->permflags = parseflags(sx); */
1743 }
1744 
1745 static void
1746 xokunseen(Imap *z, Sx *sx)
1747 {
1748 /*	z->unseen = sx->number; */
1749 }
1750 
1751 static void
1752 xokreadwrite(Imap *z, Sx *sx)
1753 {
1754 /*	z->boxmode = ORDWR; */
1755 }
1756 
1757 static void
1758 xokreadonly(Imap *z, Sx *sx)
1759 {
1760 /*	z->boxmode = OREAD; */
1761 }
1762