1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 #include <thread.h>
5 #include <cursor.h>
6 #include <mouse.h>
7 #include <keyboard.h>
8 #include <frame.h>
9 #include <fcall.h>
10 #include <9pclient.h>
11 #include <plumb.h>
12 #include <complete.h>
13 #include "dat.h"
14 #include "fns.h"
15 
16 #define MOVEIT if(0)
17 
18 enum
19 {
20 	HiWater	= 64000000,	/* max size of history */
21 	LoWater	= 400000,	/* min size of history after max'ed */
22 	MinWater	= 20000	/* room to leave available when reallocating */
23 };
24 
25 static	int		topped;
26 static	int		id;
27 
28 static	Image	*cols[NCOL];
29 static	Image	*grey;
30 static	Image	*darkgrey;
31 static	Cursor	*lastcursor;
32 static	Image	*titlecol;
33 static	Image	*lighttitlecol;
34 static	Image	*holdcol;
35 static	Image	*lightholdcol;
36 static	Image	*paleholdcol;
37 
38 static int
39 wscale(Window *w, int n)
40 {
41 	if(w == nil || w->i == nil)
42 		return n;
43 	return scalesize(w->i->display, n);
44 }
45 
46 Window*
47 wmk(Image *i, Mousectl *mc, Channel *ck, Channel *cctl, int scrolling)
48 {
49 	Window *w;
50 	Rectangle r;
51 
52 	if(cols[0] == nil){
53 		/* greys are multiples of 0x11111100+0xFF, 14* being palest */
54 		grey = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0xEEEEEEFF);
55 		darkgrey = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0x666666FF);
56 		cols[BACK] = display->white;
57 		cols[HIGH] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0xCCCCCCFF);
58 		cols[BORD] = allocimage(display, Rect(0,0,1,1), CMAP8, 1, 0x999999FF);
59 		cols[TEXT] = display->black;
60 		cols[HTEXT] = display->black;
61 		titlecol = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DGreygreen);
62 		lighttitlecol = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DPalegreygreen);
63 		holdcol = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DMedblue);
64 		lightholdcol = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DGreyblue);
65 		paleholdcol = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DPalegreyblue);
66 	}
67 	w = emalloc(sizeof(Window));
68 	w->screenr = i->r;
69 	r = insetrect(i->r, wscale(w, Selborder)+wscale(w, 1));
70 	w->i = i;
71 	w->mc = *mc;
72 	w->ck = ck;
73 	w->cctl = cctl;
74 	w->cursorp = nil;
75 	w->conswrite = chancreate(sizeof(Conswritemesg), 0);
76 	w->consread =  chancreate(sizeof(Consreadmesg), 0);
77 	w->mouseread =  chancreate(sizeof(Mousereadmesg), 0);
78 	w->wctlread =  chancreate(sizeof(Consreadmesg), 0);
79 	w->scrollr = r;
80 	w->scrollr.max.x = r.min.x+wscale(w, Scrollwid);
81 	w->lastsr = ZR;
82 	r.min.x += wscale(w, Scrollwid)+wscale(w, Scrollgap);
83 	frinit(&w->f, r, font, i, cols);
84 	w->f.maxtab = maxtab*stringwidth(font, "0");
85 	w->topped = ++topped;
86 	w->id = ++id;
87 	w->notefd = -1;
88 	w->scrolling = scrolling;
89 	w->dir = estrdup(startdir);
90 	w->label = estrdup("<unnamed>");
91 	r = insetrect(w->i->r, wscale(w, Selborder));
92 	draw(w->i, r, cols[BACK], nil, w->f.entire.min);
93 	wborder(w, wscale(w, Selborder));
94 	wscrdraw(w);
95 	incref(&w->ref);	/* ref will be removed after mounting; avoids delete before ready to be deleted */
96 	return w;
97 }
98 
99 void
100 wsetname(Window *w)
101 {
102 	int i, n;
103 	char err[ERRMAX];
104 	
105 	n = sprint(w->name, "window.%d.%d", w->id, w->namecount++);
106 	for(i='A'; i<='Z'; i++){
107 		if(nameimage(w->i, w->name, 1) > 0)
108 			return;
109 		errstr(err, sizeof err);
110 		if(strcmp(err, "image name in use") != 0)
111 			break;
112 		w->name[n] = i;
113 		w->name[n+1] = 0;
114 	}
115 	w->name[0] = 0;
116 	fprint(2, "rio: setname failed: %s\n", err);
117 }
118 
119 void
120 wresize(Window *w, Image *i, int move)
121 {
122 	Rectangle r, or;
123 
124 	or = w->i->r;
125 	if(move || (Dx(or)==Dx(i->r) && Dy(or)==Dy(i->r)))
126 		draw(i, i->r, w->i, nil, w->i->r.min);
127 	if(w->i != i){
128 fprint(2, "res %p %p\n", w->i, i);
129 		freeimage(w->i);
130 		w->i = i;
131 	}
132 /*	wsetname(w); */
133 /*XXX	w->mc.image = i; */
134 	r = insetrect(i->r, wscale(w, Selborder)+wscale(w, 1));
135 	w->scrollr = r;
136 	w->scrollr.max.x = r.min.x+wscale(w, Scrollwid);
137 	w->lastsr = ZR;
138 	r.min.x += wscale(w, Scrollwid)+wscale(w, Scrollgap);
139 	if(move)
140 		frsetrects(&w->f, r, w->i);
141 	else{
142 		frclear(&w->f, FALSE);
143 		frinit(&w->f, r, w->f.font, w->i, cols);
144 		wsetcols(w);
145 		w->f.maxtab = maxtab*stringwidth(w->f.font, "0");
146 		r = insetrect(w->i->r, wscale(w, Selborder));
147 		draw(w->i, r, cols[BACK], nil, w->f.entire.min);
148 		wfill(w);
149 		wsetselect(w, w->q0, w->q1);
150 		wscrdraw(w);
151 	}
152 	wborder(w, wscale(w, Selborder));
153 	w->topped = ++topped;
154 	w->resized = TRUE;
155 	w->mouse.counter++;
156 }
157 
158 void
159 wrefresh(Window *w, Rectangle r)
160 {
161 	/* USED(r); */
162 
163 	/* BUG: rectangle is ignored */
164 	if(w == input)
165 		wborder(w, wscale(w, Selborder));
166 	else
167 		wborder(w, wscale(w, Unselborder));
168 	if(w->mouseopen)
169 		return;
170 	draw(w->i, insetrect(w->i->r, Borderwidth), w->f.cols[BACK], nil, w->i->r.min);
171 	w->f.ticked = 0;
172 	if(w->f.p0 > 0)
173 		frdrawsel(&w->f, frptofchar(&w->f, 0), 0, w->f.p0, 0);
174 	if(w->f.p1 < w->f.nchars)
175 		frdrawsel(&w->f, frptofchar(&w->f, w->f.p1), w->f.p1, w->f.nchars, 0);
176 	frdrawsel(&w->f, frptofchar(&w->f, w->f.p0), w->f.p0, w->f.p1, 1);
177 	w->lastsr = ZR;
178 	wscrdraw(w);
179 }
180 
181 int
182 wclose(Window *w)
183 {
184 	int i;
185 
186 	i = decref(&w->ref);
187 	if(i > 0)
188 		return 0;
189 	if(i < 0)
190 		error("negative ref count");
191 	if(!w->deleted)
192 		wclosewin(w);
193 	wsendctlmesg(w, Exited, ZR, nil);
194 	return 1;
195 }
196 
197 
198 void
199 winctl(void *arg)
200 {
201 	Rune *rp, *bp, *up, *kbdr;
202 	uint qh;
203 	int nr, nb, c, wid, i, npart, initial, lastb, scrolling;
204 	char *s, *t, part[UTFmax];
205 	Window *w;
206 	Mousestate *mp, m;
207 	enum { WKey, WMouse, WMouseread, WCtl, WCwrite, WCread, WWread, NWALT };
208 	Alt alts[NWALT+1];
209 	Mousereadmesg mrm;
210 	Conswritemesg cwm;
211 	Consreadmesg crm;
212 	Consreadmesg cwrm;
213 	Stringpair pair;
214 	Wctlmesg wcm;
215 	char buf[4*12+1];
216 
217 	w = arg;
218 	snprint(buf, sizeof buf, "winctl-id%d", w->id);
219 	threadsetname(buf);
220 
221 	mrm.cm = chancreate(sizeof(Mouse), 0);
222 	cwm.cw = chancreate(sizeof(Stringpair), 0);
223 	crm.c1 = chancreate(sizeof(Stringpair), 0);
224 	crm.c2 = chancreate(sizeof(Stringpair), 0);
225 	cwrm.c1 = chancreate(sizeof(Stringpair), 0);
226 	cwrm.c2 = chancreate(sizeof(Stringpair), 0);
227 	
228 
229 	alts[WKey].c = w->ck;
230 	alts[WKey].v = &kbdr;
231 	alts[WKey].op = CHANRCV;
232 	alts[WMouse].c = w->mc.c;
233 	alts[WMouse].v = &w->mc.m;
234 	alts[WMouse].op = CHANRCV;
235 	alts[WMouseread].c = w->mouseread;
236 	alts[WMouseread].v = &mrm;
237 	alts[WMouseread].op = CHANSND;
238 	alts[WCtl].c = w->cctl;
239 	alts[WCtl].v = &wcm;
240 	alts[WCtl].op = CHANRCV;
241 	alts[WCwrite].c = w->conswrite;
242 	alts[WCwrite].v = &cwm;
243 	alts[WCwrite].op = CHANSND;
244 	alts[WCread].c = w->consread;
245 	alts[WCread].v = &crm;
246 	alts[WCread].op = CHANSND;
247 	alts[WWread].c = w->wctlread;
248 	alts[WWread].v = &cwrm;
249 	alts[WWread].op = CHANSND;
250 	alts[NWALT].op = CHANEND;
251 
252 	npart = 0;
253 	lastb = -1;
254 	for(;;){
255 		if(w->mouseopen && w->mouse.counter != w->mouse.lastcounter)
256 			alts[WMouseread].op = CHANSND;
257 		else
258 			alts[WMouseread].op = CHANNOP;
259 		//	if(!w->scrolling && !w->mouseopen && w->qh>w->org+w->f.nchars)
260 		//		alts[WCwrite].op = CHANNOP;
261 		//	else
262 		alts[WCwrite].op = CHANSND;
263 		if(w->deleted || !w->wctlready)
264 			alts[WWread].op = CHANNOP;
265 		else
266 			alts[WWread].op = CHANSND;
267 		/* this code depends on NL and EOT fitting in a single byte */
268 		/* kind of expensive for each loop; worth precomputing? */
269 		if(w->holding)
270 			alts[WCread].op = CHANNOP;
271 		else if(npart || (w->rawing && w->nraw>0))
272 			alts[WCread].op = CHANSND;
273 		else{
274 			alts[WCread].op = CHANNOP;
275 			for(i=w->qh; i<w->nr; i++){
276 				c = w->r[i];
277 				if(c=='\n' || c=='\004'){
278 					alts[WCread].op = CHANSND;
279 					break;
280 				}
281 			}
282 		}
283 		switch(alt(alts)){
284 		case WKey:
285 			for(i=0; kbdr[i]!=L'\0'; i++)
286 				wkeyctl(w, kbdr[i]);
287 /*			wkeyctl(w, r); */
288 /*			while(nbrecv(w->ck, &r)) */
289 /*				wkeyctl(w, r); */
290 			break;
291 		case WMouse:
292 			if(w->mouseopen) {
293 				w->mouse.counter++;
294 
295 				/* queue click events */
296 				if(!w->mouse.qfull && lastb != w->mc.m.buttons) {	/* add to ring */
297 					mp = &w->mouse.queue[w->mouse.wi];
298 					if(++w->mouse.wi == nelem(w->mouse.queue))
299 						w->mouse.wi = 0;
300 					if(w->mouse.wi == w->mouse.ri)
301 						w->mouse.qfull = TRUE;
302 					mp->m = w->mc.m;
303 					mp->counter = w->mouse.counter;
304 					lastb = w->mc.m.buttons;
305 				}
306 			} else
307 				wmousectl(w);
308 			break;
309 		case WMouseread:
310 			/* send a queued event or, if the queue is empty, the current state */
311 			/* if the queue has filled, we discard all the events it contained. */
312 			/* the intent is to discard frantic clicking by the user during long latencies. */
313 			w->mouse.qfull = FALSE;
314 			if(w->mouse.wi != w->mouse.ri) {
315 				m = w->mouse.queue[w->mouse.ri];
316 				if(++w->mouse.ri == nelem(w->mouse.queue))
317 					w->mouse.ri = 0;
318 			} else {
319 				m.m = w->mc.m;
320 				m.counter = w->mouse.counter;
321 			}
322 			w->mouse.lastcounter = m.counter;
323 			send(mrm.cm, &m.m);
324 			continue;
325 		case WCtl:
326 			if(wctlmesg(w, wcm.type, wcm.r, wcm.image) == Exited){
327 				chanfree(crm.c1);
328 				chanfree(crm.c2);
329 				chanfree(mrm.cm);
330 				chanfree(cwm.cw);
331 				chanfree(cwrm.c1);
332 				chanfree(cwrm.c2);
333 				threadexits(nil);
334 			}
335 			continue;
336 		case WCwrite:
337 			recv(cwm.cw, &pair);
338 			rp = pair.s;
339 			nr = pair.ns;
340 			bp = rp;
341 			up = rp;
342 			initial = 0;
343 			for(i=0; i<nr; i++){
344 				switch(*bp){
345 				case 0:
346 					break;
347 				case '\b':
348 					if(up == rp)
349 						initial++;
350 					else
351 						--up;
352 					break;
353 				case '\r':
354 					while(i<nr-1 && *(bp+1) == '\r'){
355 						bp++;
356 						i++;
357 					}
358 					if(i<nr-1 && *(bp+1) != '\n'){
359 						while(up > rp && *(up-1) != '\n')
360 							up--;
361 						if(up == rp)
362 							initial = wbswidth(w, '\r');
363 					}else if(i == nr-1)
364 						*up = '\n';
365 					break;
366 				default:
367 					*up++ = *bp;
368 					break;
369 				}
370 				bp++;
371 			}
372 			if(initial){
373 				if(initial > w->qh)
374 					initial = w->qh;
375 				qh = w->qh - initial;
376 				wdelete(w, qh, qh+initial);
377 				w->qh = qh;
378 			}
379 			nr = up - rp;
380 			scrolling = w->scrolling && w->org <= w->qh && w->qh <= w->org + w->f.nchars;
381 			w->qh = winsert(w, rp, nr, w->qh)+nr;
382 			if(scrolling)
383 				wshow(w, w->qh);
384 			wsetselect(w, w->q0, w->q1);
385 			wscrdraw(w);
386 			free(rp);
387 			break;
388 		case WCread:
389 			recv(crm.c1, &pair);
390 			t = pair.s;
391 			nb = pair.ns;
392 			i = npart;
393 			npart = 0;
394 			if(i)
395 				memmove(t, part, i);
396 			while(i<nb && (w->qh<w->nr || w->nraw>0)){
397 				if(w->qh == w->nr){
398 					wid = runetochar(t+i, &w->raw[0]);
399 					w->nraw--;
400 					runemove(w->raw, w->raw+1, w->nraw);
401 				}else
402 					wid = runetochar(t+i, &w->r[w->qh++]);
403 				c = t[i];	/* knows break characters fit in a byte */
404 				i += wid;
405 				if(!w->rawing && (c == '\n' || c=='\004')){
406 				/*	if(c == '\004') */
407 				/*		i--; */
408 					break;
409 				}
410 			}
411 		/*	if(i==nb && w->qh<w->nr && w->r[w->qh]=='\004') */
412 		/*		w->qh++; */
413 			if(i > nb){
414 				npart = i-nb;
415 				memmove(part, t+nb, npart);
416 				i = nb;
417 			}
418 			pair.s = t;
419 			pair.ns = i;
420 			send(crm.c2, &pair);
421 			continue;
422 		case WWread:
423 			w->wctlready = 0;
424 			recv(cwrm.c1, &pair);
425 			if(w->deleted || w->i==nil)
426 				pair.ns = sprint(pair.s, "");
427 			else{
428 				s = "visible";
429 				for(i=0; i<nhidden; i++)
430 					if(hidden[i] == w){
431 						s = "hidden";
432 						break;
433 					}
434 				t = "notcurrent";
435 				if(w == input)
436 					t = "current";
437 				pair.ns = snprint(pair.s, pair.ns, "%11d %11d %11d %11d %s %s ",
438 					w->i->r.min.x, w->i->r.min.y, w->i->r.max.x, w->i->r.max.y, t, s);
439 			}
440 			send(cwrm.c2, &pair);
441 			continue;
442 		}
443 		if(!w->deleted)
444 			flushimage(display, 1);
445 	}
446 }
447 
448 void
449 waddraw(Window *w, Rune *r, int nr)
450 {
451 	w->raw = runerealloc(w->raw, w->nraw+nr);
452 	runemove(w->raw+w->nraw, r, nr);
453 	w->nraw += nr;
454 }
455 
456 /*
457  * Need to do this in a separate proc because if process we're interrupting
458  * is dying and trying to print tombstone, kernel is blocked holding p->debug lock.
459  */
460 void
461 interruptproc(void *v)
462 {
463 	int *notefd;
464 
465 	notefd = v;
466 	write(*notefd, "interrupt", 9);
467 	free(notefd);
468 }
469 
470 int
471 windfilewidth(Window *w, uint q0, int oneelement)
472 {
473 	uint q;
474 	Rune r;
475 
476 	q = q0;
477 	while(q > 0){
478 		r = w->r[q-1];
479 		if(r<=' ')
480 			break;
481 		if(oneelement && r=='/')
482 			break;
483 		--q;
484 	}
485 	return q0-q;
486 }
487 
488 void
489 showcandidates(Window *w, Completion *c)
490 {
491 	int i;
492 	Fmt f;
493 	Rune *rp;
494 	uint nr, qline, q0;
495 	char *s;
496 
497 	runefmtstrinit(&f);
498 	if (c->nmatch == 0)
499 		s = "[no matches in ";
500 	else
501 		s = "[";
502 	if(c->nfile > 32)
503 		fmtprint(&f, "%s%d files]\n", s, c->nfile);
504 	else{
505 		fmtprint(&f, "%s", s);
506 		for(i=0; i<c->nfile; i++){
507 			if(i > 0)
508 				fmtprint(&f, " ");
509 			fmtprint(&f, "%s", c->filename[i]);
510 		}
511 		fmtprint(&f, "]\n");
512 	}
513 	/* place text at beginning of line before host point */
514 	qline = w->qh;
515 	while(qline>0 && w->r[qline-1] != '\n')
516 		qline--;
517 
518 	rp = runefmtstrflush(&f);
519 	nr = runestrlen(rp);
520 
521 	q0 = w->q0;
522 	q0 += winsert(w, rp, runestrlen(rp), qline) - qline;
523 	free(rp);
524 	wsetselect(w, q0+nr, q0+nr);
525 }
526 
527 Rune*
528 namecomplete(Window *w)
529 {
530 	int nstr, npath;
531 	Rune *rp, *path, *str;
532 	Completion *c;
533 	char *s, *dir, *root;
534 
535 	/* control-f: filename completion; works back to white space or / */
536 	if(w->q0<w->nr && w->r[w->q0]>' ')	/* must be at end of word */
537 		return nil;
538 	nstr = windfilewidth(w, w->q0, TRUE);
539 	str = runemalloc(nstr);
540 	runemove(str, w->r+(w->q0-nstr), nstr);
541 	npath = windfilewidth(w, w->q0-nstr, FALSE);
542 	path = runemalloc(npath);
543 	runemove(path, w->r+(w->q0-nstr-npath), npath);
544 	rp = nil;
545 
546 	/* is path rooted? if not, we need to make it relative to window path */
547 	if(npath>0 && path[0]=='/'){
548 		dir = malloc(UTFmax*npath+1);
549 		sprint(dir, "%.*S", npath, path);
550 	}else{
551 		if(strcmp(w->dir, "") == 0)
552 			root = ".";
553 		else
554 			root = w->dir;
555 		dir = malloc(strlen(root)+1+UTFmax*npath+1);
556 		sprint(dir, "%s/%.*S", root, npath, path);
557 	}
558 	dir = cleanname(dir);
559 
560 	s = smprint("%.*S", nstr, str);
561 	c = complete(dir, s);
562 	free(s);
563 	if(c == nil)
564 		goto Return;
565 
566 	if(!c->advance)
567 		showcandidates(w, c);
568 
569 	if(c->advance)
570 		rp = runesmprint("%s", c->string);
571 
572   Return:
573 	freecompletion(c);
574 	free(dir);
575 	free(path);
576 	free(str);
577 	return rp;
578 }
579 
580 void
581 wkeyctl(Window *w, Rune r)
582 {
583 	uint q0 ,q1;
584 	int n, nb, nr;
585 	Rune *rp;
586 
587 	if(r == 0)
588 		return;
589 	if(w->deleted)
590 		return;
591 	w->rawing = rawon();
592 	/* navigation keys work only when mouse is not open */
593 	if(!w->mouseopen)
594 		switch(r){
595 		case Kdown:
596 			n = w->f.maxlines/3;
597 			goto case_Down;
598 		case Kscrollonedown:
599 			n = mousescrollsize(w->f.maxlines);
600 			if(n <= 0)
601 				n = 1;
602 			goto case_Down;
603 		case Kpgdown:
604 			n = 2*w->f.maxlines/3;
605 		case_Down:
606 			q0 = w->org+frcharofpt(&w->f, Pt(w->f.r.min.x, w->f.r.min.y+n*w->f.font->height));
607 			wsetorigin(w, q0, TRUE);
608 			return;
609 		case Kup:
610 			n = w->f.maxlines/3;
611 			goto case_Up;
612 		case Kscrolloneup:
613 			n = mousescrollsize(w->f.maxlines);
614 			if(n <= 0)
615 				n = 1;
616 			goto case_Up;
617 		case Kpgup:
618 			n = 2*w->f.maxlines/3;
619 		case_Up:
620 			q0 = wbacknl(w, w->org, n);
621 			wsetorigin(w, q0, TRUE);
622 			return;
623 		case Kleft:
624 			if(w->q0 > 0){
625 				q0 = w->q0-1;
626 				wsetselect(w, q0, q0);
627 				wshow(w, q0);
628 			}
629 			return;
630 		case Kright:
631 			if(w->q1 < w->nr){
632 				q1 = w->q1+1;
633 				wsetselect(w, q1, q1);
634 				wshow(w, q1);
635 			}
636 			return;
637 		case Khome:
638 			if(w->org > w->iq1) {
639 				q0 = wbacknl(w, w->iq1, 1);
640 				wsetorigin(w, q0, TRUE);
641 			} else
642 				wshow(w, 0);
643 			return;
644 		case Kend:
645 			if(w->iq1 > w->org+w->f.nchars) {
646 				q0 = wbacknl(w, w->iq1, 1);
647 				wsetorigin(w, q0, TRUE);
648 			} else
649 				wshow(w, w->nr);
650 			return;
651 		case 0x01:	/* ^A: beginning of line */
652 			if(w->q0==0 || w->q0==w->qh || w->r[w->q0-1]=='\n')
653 				return;
654 			nb = wbswidth(w, 0x15 /* ^U */);
655 			wsetselect(w, w->q0-nb, w->q0-nb);
656 			wshow(w, w->q0);
657 			return;
658 		case 0x05:	/* ^E: end of line */
659 			q0 = w->q0;
660 			while(q0 < w->nr && w->r[q0]!='\n')
661 				q0++;
662 			wsetselect(w, q0, q0);
663 			wshow(w, w->q0);
664 			return;
665 		}
666 	/*
667 	 * This if used to be below the if(w->rawing ...),
668 	 * but let's try putting it here.  This will allow ESC-processing
669 	 * to toggle hold mode even in remote SSH connections.
670 	 * The drawback is that vi-style processing gets harder.
671 	 * If you find yourself in some weird readline mode, good
672 	 * luck getting out without ESC.  Let's see who complains.
673 	 */
674 	if(r==0x1B || (w->holding && r==0x7F)){	/* toggle hold */
675 		if(w->holding)
676 			--w->holding;
677 		else
678 			w->holding++;
679 		wrepaint(w);
680 		if(r == 0x1B)
681 			return;
682 	}
683 	if(!w->holding && w->rawing && (w->q0==w->nr || w->mouseopen)){
684 		waddraw(w, &r, 1);
685 		return;
686 	}
687 	if(r == Kcmd+'x'){
688 		wsnarf(w);
689 		wcut(w);
690 		wscrdraw(w);
691 		return;
692 	}
693 	if(r == Kcmd+'c'){
694 		wsnarf(w);
695 		return;
696 	}
697 	if(r == Kcmd+'v'){
698 		riogetsnarf();
699 		wpaste(w);
700 		wscrdraw(w);
701 		return;
702 	}
703 	if(r != 0x7F){
704 		wsnarf(w);
705 		wcut(w);
706 	}
707 	switch(r){
708 	case 0x7F:		/* send interrupt */
709 		w->qh = w->nr;
710 		wshow(w, w->qh);
711 		winterrupt(w);
712 		w->iq1 = w->q0;
713 		return;
714 	case 0x06:	/* ^F: file name completion */
715 	case Kins:		/* Insert: file name completion */
716 		rp = namecomplete(w);
717 		if(rp == nil)
718 			return;
719 		nr = runestrlen(rp);
720 		q0 = w->q0;
721 		q0 = winsert(w, rp, nr, q0);
722 		wshow(w, q0+nr);
723 		w->iq1 = w->q0;
724 		free(rp);
725 		return;
726 	case 0x08:	/* ^H: erase character */
727 	case 0x15:	/* ^U: erase line */
728 	case 0x17:	/* ^W: erase word */
729 		if(w->q0==0 || w->q0==w->qh)
730 			return;
731 		nb = wbswidth(w, r);
732 		q1 = w->q0;
733 		q0 = q1-nb;
734 		if(q0 < w->org){
735 			q0 = w->org;
736 			nb = q1-q0;
737 		}
738 		if(nb > 0){
739 			wdelete(w, q0, q0+nb);
740 			wsetselect(w, q0, q0);
741 		}
742 		w->iq1 = w->q0;
743 		return;
744 	}
745 	/* otherwise ordinary character; just insert */
746 	q0 = w->q0;
747 	q0 = winsert(w, &r, 1, q0);
748 	wshow(w, q0+1);
749 	w->iq1 = w->q0;
750 }
751 
752 void
753 wsetcols(Window *w)
754 {
755 	if(w->holding)
756 		if(w == input)
757 			w->f.cols[TEXT] = w->f.cols[HTEXT] = holdcol;
758 		else
759 			w->f.cols[TEXT] = w->f.cols[HTEXT] = lightholdcol;
760 	else
761 		if(w == input)
762 			w->f.cols[TEXT] = w->f.cols[HTEXT] = display->black;
763 		else
764 			w->f.cols[TEXT] = w->f.cols[HTEXT] = darkgrey;
765 }
766 
767 void
768 wrepaint(Window *w)
769 {
770 	wsetcols(w);
771 	if(!w->mouseopen){
772 		frredraw(&w->f);
773 	}
774 	if(w == input){
775 		wborder(w, wscale(w, Selborder));
776 		wsetcursor(w, 0);
777 	}else
778 		wborder(w, wscale(w, Unselborder));
779 }
780 
781 int
782 wbswidth(Window *w, Rune c)
783 {
784 	uint q, eq, stop;
785 	Rune r;
786 	int skipping;
787 
788 	/* there is known to be at least one character to erase */
789 	if(c == 0x08)	/* ^H: erase character */
790 		return 1;
791 	q = w->q0;
792 	stop = 0;
793 	if(q > w->qh)
794 		stop = w->qh;
795 	skipping = TRUE;
796 	while(q > stop){
797 		r = w->r[q-1];
798 		if(r == '\n'){		/* eat at most one more character */
799 			if(q == w->q0 && c != '\r')	/* eat the newline */
800 				--q;
801 			break; 
802 		}
803 		if(c == 0x17){
804 			eq = isalnum(r);
805 			if(eq && skipping)	/* found one; stop skipping */
806 				skipping = FALSE;
807 			else if(!eq && !skipping)
808 				break;
809 		}
810 		--q;
811 	}
812 	return w->q0-q;
813 }
814 
815 void
816 wsnarf(Window *w)
817 {
818 	if(w->q1 == w->q0)
819 		return;
820 	nsnarf = w->q1-w->q0;
821 	snarf = runerealloc(snarf, nsnarf);
822 	snarfversion++;	/* maybe modified by parent */
823 	runemove(snarf, w->r+w->q0, nsnarf);
824 	rioputsnarf();
825 }
826 
827 void
828 wcut(Window *w)
829 {
830 	if(w->q1 == w->q0)
831 		return;
832 	wdelete(w, w->q0, w->q1);
833 	wsetselect(w, w->q0, w->q0);
834 }
835 
836 void
837 wpaste(Window *w)
838 {
839 	uint q0;
840 
841 	if(nsnarf == 0)
842 		return;
843 	wcut(w);
844 	q0 = w->q0;
845 	if(w->rawing && !w->holding && q0==w->nr){
846 		waddraw(w, snarf, nsnarf);
847 		wsetselect(w, q0, q0);
848 	}else{
849 		q0 = winsert(w, snarf, nsnarf, w->q0);
850 		wsetselect(w, q0, q0+nsnarf);
851 	}
852 }
853 
854 void
855 wplumb(Window *w)
856 {
857 	Plumbmsg *m;
858 	static CFid *fd;
859 	char buf[32];
860 	uint p0, p1;
861 	Cursor *c;
862 
863 	if(fd == nil)
864 		fd = plumbopenfid("send", OWRITE);
865 	if(fd == nil)
866 		return;
867 	m = emalloc(sizeof(Plumbmsg));
868 	m->src = estrdup("rio");
869 	m->dst = nil;
870 	m->wdir = estrdup(w->dir);
871 	m->type = estrdup("text");
872 	p0 = w->q0;
873 	p1 = w->q1;
874 	if(w->q1 > w->q0)
875 		m->attr = nil;
876 	else{
877 		while(p0>0 && w->r[p0-1]!=' ' && w->r[p0-1]!='\t' && w->r[p0-1]!='\n')
878 			p0--;
879 		while(p1<w->nr && w->r[p1]!=' ' && w->r[p1]!='\t' && w->r[p1]!='\n')
880 			p1++;
881 		sprint(buf, "click=%d", w->q0-p0);
882 		m->attr = plumbunpackattr(buf);
883 	}
884 	if(p1-p0 > messagesize-1024){
885 		plumbfree(m);
886 		return;	/* too large for 9P */
887 	}
888 	m->data = runetobyte(w->r+p0, p1-p0, &m->ndata);
889 	if(plumbsendtofid(fd, m) < 0){
890 		c = lastcursor;
891 		riosetcursor(&query, 1);
892 		sleep(300);
893 		riosetcursor(c, 1);
894 	}
895 	plumbfree(m);
896 }
897 
898 int
899 winborder(Window *w, Point xy)
900 {
901 	return ptinrect(xy, w->screenr) && !ptinrect(xy, insetrect(w->screenr, wscale(w, Selborder)));
902 }
903 
904 void
905 wmousectl(Window *w)
906 {
907 	int but;
908 
909 	if(w->mc.m.buttons == 1)
910 		but = 1;
911 	else if(w->mc.m.buttons == 2)
912 		but = 2;
913 	else if(w->mc.m.buttons == 4)
914 		but = 3;
915 	else{
916 		if(w->mc.m.buttons == 8)
917 			wkeyctl(w, Kscrolloneup);
918 		if(w->mc.m.buttons == 16)
919 			wkeyctl(w, Kscrollonedown);
920 		return;
921 	}
922 
923 	incref(&w->ref);		/* hold up window while we track */
924 	if(w->deleted)
925 		goto Return;
926 	if(ptinrect(w->mc.m.xy, w->scrollr)){
927 		if(but)
928 			wscroll(w, but);
929 		goto Return;
930 	}
931 	if(but == 1)
932 		wselect(w);
933 	/* else all is handled by main process */
934    Return:
935 	wclose(w);
936 }
937 
938 void
939 wdelete(Window *w, uint q0, uint q1)
940 {
941 	uint n, p0, p1;
942 
943 	n = q1-q0;
944 	if(n == 0)
945 		return;
946 	runemove(w->r+q0, w->r+q1, w->nr-q1);
947 	w->nr -= n;
948 	if(q0 < w->iq1)
949 		w->iq1 -= min(n, w->iq1-q0);
950 	if(q0 < w->q0)
951 		w->q0 -= min(n, w->q0-q0);
952 	if(q0 < w->q1)
953 		w->q1 -= min(n, w->q1-q0);
954 	if(q1 < w->qh)
955 		w->qh -= n;
956 	else if(q0 < w->qh)
957 		w->qh = q0;
958 	if(q1 <= w->org)
959 		w->org -= n;
960 	else if(q0 < w->org+w->f.nchars){
961 		p1 = q1 - w->org;
962 		if(p1 > w->f.nchars)
963 			p1 = w->f.nchars;
964 		if(q0 < w->org){
965 			w->org = q0;
966 			p0 = 0;
967 		}else
968 			p0 = q0 - w->org;
969 		frdelete(&w->f, p0, p1);
970 		wfill(w);
971 	}
972 }
973 
974 
975 static Window	*clickwin;
976 static uint	clickmsec;
977 static Window	*selectwin;
978 static uint	selectq;
979 
980 /*
981  * called from frame library
982  */
983 void
984 framescroll(Frame *f, int dl)
985 {
986 	if(f != &selectwin->f)
987 		error("frameselect not right frame");
988 	wframescroll(selectwin, dl);
989 }
990 
991 void
992 wframescroll(Window *w, int dl)
993 {
994 	uint q0;
995 
996 	if(dl == 0){
997 		wscrsleep(w, 100);
998 		return;
999 	}
1000 	if(dl < 0){
1001 		q0 = wbacknl(w, w->org, -dl);
1002 		if(selectq > w->org+w->f.p0)
1003 			wsetselect(w, w->org+w->f.p0, selectq);
1004 		else
1005 			wsetselect(w, selectq, w->org+w->f.p0);
1006 	}else{
1007 		if(w->org+w->f.nchars == w->nr)
1008 			return;
1009 		q0 = w->org+frcharofpt(&w->f, Pt(w->f.r.min.x, w->f.r.min.y+dl*w->f.font->height));
1010 		if(selectq >= w->org+w->f.p1)
1011 			wsetselect(w, w->org+w->f.p1, selectq);
1012 		else
1013 			wsetselect(w, selectq, w->org+w->f.p1);
1014 	}
1015 	wsetorigin(w, q0, TRUE);
1016 }
1017 
1018 void
1019 wselect(Window *w)
1020 {
1021 	uint q0, q1;
1022 	int b, x, y, first;
1023 
1024 	first = 1;
1025 	selectwin = w;
1026 	/*
1027 	 * Double-click immediately if it might make sense.
1028 	 */
1029 	b = w->mc.m.buttons;
1030 	q0 = w->q0;
1031 	q1 = w->q1;
1032 	selectq = w->org+frcharofpt(&w->f, w->mc.m.xy);
1033 	if(clickwin==w && w->mc.m.msec-clickmsec<500)
1034 	if(q0==q1 && selectq==w->q0){
1035 		wdoubleclick(w, &q0, &q1);
1036 		wsetselect(w, q0, q1);
1037 		flushimage(display, 1);
1038 		x = w->mc.m.xy.x;
1039 		y = w->mc.m.xy.y;
1040 		/* stay here until something interesting happens */
1041 		do
1042 			readmouse(&w->mc);
1043 		while(w->mc.m.buttons==b && abs(w->mc.m.xy.x-x)<3 && abs(w->mc.m.xy.y-y)<3);
1044 		w->mc.m.xy.x = x;	/* in case we're calling frselect */
1045 		w->mc.m.xy.y = y;
1046 		q0 = w->q0;	/* may have changed */
1047 		q1 = w->q1;
1048 		selectq = q0;
1049 	}
1050 	if(w->mc.m.buttons == b){
1051 		w->f.scroll = framescroll;
1052 		frselect(&w->f, &w->mc);
1053 		/* horrible botch: while asleep, may have lost selection altogether */
1054 		if(selectq > w->nr)
1055 			selectq = w->org + w->f.p0;
1056 		w->f.scroll = nil;
1057 		if(selectq < w->org)
1058 			q0 = selectq;
1059 		else
1060 			q0 = w->org + w->f.p0;
1061 		if(selectq > w->org+w->f.nchars)
1062 			q1 = selectq;
1063 		else
1064 			q1 = w->org+w->f.p1;
1065 	}
1066 	if(q0 == q1){
1067 		if(q0==w->q0 && clickwin==w && w->mc.m.msec-clickmsec<500){
1068 			wdoubleclick(w, &q0, &q1);
1069 			clickwin = nil;
1070 		}else{
1071 			clickwin = w;
1072 			clickmsec = w->mc.m.msec;
1073 		}
1074 	}else
1075 		clickwin = nil;
1076 	wsetselect(w, q0, q1);
1077 	flushimage(display, 1);
1078 	while(w->mc.m.buttons){
1079 		w->mc.m.msec = 0;
1080 		b = w->mc.m.buttons;
1081 		if(b & 6){
1082 			if(b & 2){
1083 				wsnarf(w);
1084 				wcut(w);
1085 			}else{
1086 				if(first){
1087 					first = 0;
1088 					riogetsnarf();
1089 				}
1090 				wpaste(w);
1091 			}
1092 		}
1093 		wscrdraw(w);
1094 		flushimage(display, 1);
1095 		while(w->mc.m.buttons == b)
1096 			readmouse(&w->mc);
1097 		clickwin = nil;
1098 	}
1099 }
1100 
1101 void
1102 wsendctlmesg(Window *w, int type, Rectangle r, Image *image)
1103 {
1104 	Wctlmesg wcm;
1105 
1106 	wcm.type = type;
1107 	wcm.r = r;
1108 	wcm.image = image;
1109 	send(w->cctl, &wcm);
1110 }
1111 
1112 int
1113 wctlmesg(Window *w, int m, Rectangle r, Image *i)
1114 {
1115 	char buf[64];
1116 
1117 	switch(m){
1118 	default:
1119 		error("unknown control message");
1120 		break;
1121 	case Wakeup:
1122 		break;
1123 	case Moved:
1124 	case Reshaped:
1125 		if(w->deleted){
1126 			freeimage(i);
1127 			break;
1128 		}
1129 		w->screenr = r;
1130 		strcpy(buf, w->name);
1131 		wresize(w, i, m==Moved);
1132 		w->wctlready = 1;
1133 		if(Dx(r) > 0){
1134 			if(w != input)
1135 				wcurrent(w);
1136 		}else if(w == input)
1137 			wcurrent(nil);
1138 		flushimage(display, 1);
1139 		break;
1140 	case Refresh:
1141 		if(w->deleted || Dx(w->screenr)<=0 || !rectclip(&r, w->i->r))
1142 			break;
1143 		if(!w->mouseopen)
1144 			wrefresh(w, r);
1145 		flushimage(display, 1);
1146 		break;
1147 	case Movemouse:
1148 		if(sweeping || !ptinrect(r.min, w->i->r))
1149 			break;
1150 		wmovemouse(w, r.min);
1151 	case Rawon:
1152 		break;
1153 	case Rawoff:
1154 		if(w->deleted)
1155 			break;
1156 		while(w->nraw > 0){
1157 			wkeyctl(w, w->raw[0]);
1158 			--w->nraw;
1159 			runemove(w->raw, w->raw+1, w->nraw);
1160 		}
1161 		break;
1162 	case Holdon:
1163 	case Holdoff:
1164 		if(w->deleted)
1165 			break;
1166 		wrepaint(w);
1167 		flushimage(display, 1);
1168 		break;
1169 	case Deleted:
1170 		if(w->deleted)
1171 			break;
1172 		write(w->notefd, "hangup", 6);
1173 		wclosewin(w);
1174 		break;
1175 	case Exited:
1176 		frclear(&w->f, TRUE);
1177 		close(w->notefd);
1178 		chanfree(w->mc.c);
1179 		chanfree(w->ck);
1180 		chanfree(w->cctl);
1181 		chanfree(w->conswrite);
1182 		chanfree(w->consread);
1183 		chanfree(w->mouseread);
1184 		chanfree(w->wctlread);
1185 		free(w->raw);
1186 		free(w->r);
1187 		free(w->dir);
1188 		free(w->label);
1189 		free(w);
1190 		break;
1191 	}
1192 	return m;
1193 }
1194 
1195 /*
1196  * Convert back to physical coordinates
1197  */
1198 void
1199 wmovemouse(Window *w, Point p)
1200 {
1201 	p.x += w->screenr.min.x-w->i->r.min.x;
1202 	p.y += w->screenr.min.y-w->i->r.min.y;
1203 	moveto(mousectl, p);
1204 }
1205 
1206 void
1207 wcurrent(Window *w)
1208 {
1209 	Window *oi;
1210 
1211 	if(wkeyboard!=nil && w==wkeyboard)
1212 		return;
1213 	oi = input;
1214 	input = w;
1215 	if(oi!=w && oi!=nil)
1216 		wrepaint(oi);
1217 	if(w !=nil){
1218 		wrepaint(w);
1219 		wsetcursor(w, 0);
1220 	}
1221 	if(w != oi){
1222 		if(oi){
1223 			oi->wctlready = 1;
1224 			wsendctlmesg(oi, Wakeup, ZR, nil);
1225 		}
1226 		if(w){
1227 			w->wctlready = 1;
1228 			wsendctlmesg(w, Wakeup, ZR, nil);
1229 		}
1230 	}
1231 }
1232 
1233 void
1234 wsetcursor(Window *w, int force)
1235 {
1236 	Cursor *p;
1237 
1238 	if(w==nil || /*w!=input || */ w->i==nil || Dx(w->screenr)<=0)
1239 		p = nil;
1240 	else if(wpointto(mouse->xy) == w){
1241 		p = w->cursorp;
1242 		if(p==nil && w->holding)
1243 			p = &whitearrow;
1244 	}else
1245 		p = nil;
1246 	if(!menuing)
1247 		riosetcursor(p, force && !menuing);
1248 }
1249 
1250 void
1251 riosetcursor(Cursor *p, int force)
1252 {
1253 	if(!force && p==lastcursor)
1254 		return;
1255 	setcursor(mousectl, p);
1256 	lastcursor = p;
1257 }
1258 
1259 Window*
1260 wtop(Point pt)
1261 {
1262 	Window *w;
1263 
1264 	w = wpointto(pt);
1265 	if(w){
1266 		if(w->topped == topped)
1267 			return nil;
1268 		topwindow(w->i);
1269 		wcurrent(w);
1270 		flushimage(display, 1);
1271 		w->topped = ++topped;
1272 	}
1273 	return w;
1274 }
1275 
1276 void
1277 wtopme(Window *w)
1278 {
1279 	if(w!=nil && w->i!=nil && !w->deleted && w->topped!=topped){
1280 		topwindow(w->i);
1281 		flushimage(display, 1);
1282 		w->topped = ++ topped;
1283 	}
1284 }
1285 
1286 void
1287 wbottomme(Window *w)
1288 {
1289 	if(w!=nil && w->i!=nil && !w->deleted){
1290 		bottomwindow(w->i);
1291 		flushimage(display, 1);
1292 		w->topped = 0;
1293 	}
1294 }
1295 
1296 Window*
1297 wlookid(int id)
1298 {
1299 	int i;
1300 
1301 	for(i=0; i<nwindow; i++)
1302 		if(window[i]->id == id)
1303 			return window[i];
1304 	return nil;
1305 }
1306 
1307 void
1308 wclosewin(Window *w)
1309 {
1310 	Rectangle r;
1311 	int i;
1312 
1313 	w->deleted = TRUE;
1314 	if(w == input){
1315 		input = nil;
1316 		wsetcursor(w, 0);
1317 	}
1318 	if(w == wkeyboard)
1319 		wkeyboard = nil;
1320 	for(i=0; i<nhidden; i++)
1321 		if(hidden[i] == w){
1322 			--nhidden;
1323 			memmove(hidden+i, hidden+i+1, (nhidden-i)*sizeof(hidden[0]));
1324 			break;
1325 		}
1326 	for(i=0; i<nwindow; i++)
1327 		if(window[i] == w){
1328 			--nwindow;
1329 			memmove(window+i, window+i+1, (nwindow-i)*sizeof(Window*));
1330 			w->deleted = TRUE;
1331 			r = w->i->r;
1332 			/* move it off-screen to hide it, in case client is slow in letting it go */
1333 			MOVEIT originwindow(w->i, r.min, view->r.max);
1334 			freeimage(w->i);
1335 			w->i = nil;
1336 			return;
1337 		}
1338 	error("unknown window in closewin");
1339 }
1340 
1341 void
1342 wsetpid(Window *w, int pid, int dolabel)
1343 {
1344 	char buf[128];
1345 
1346 	w->pid = pid;
1347 	if(dolabel){
1348 		sprint(buf, "rc %d", pid);
1349 		free(w->label);
1350 		w->label = estrdup(buf);
1351 		drawsetlabel(w->label);
1352 	}
1353 }
1354 
1355 static Rune left1[] =  { 
1356 	'{', '[', '(', '<', 0xAB,
1357 	0x207d, 0x2329, 0x27e6, 0x27e8, 0x27ea, 
1358 	0xfe59, 0xfe5b, 0xfe5d, 0xff08, 0xff3b, 0xff5b, 
1359 	0
1360 };
1361 static Rune right1[] = {
1362 	'}', ']', ')', '>', 0xBB,
1363 	0x207e, 0x232a, 0x27e7, 0x27e9, 0x27eb, 
1364 	0xfe5a, 0xfe5c, 0xfe5e, 0xff09, 0xff3d, 0xff5d,
1365 	0
1366 };
1367 static Rune left2[] =  { '\n', 0 };
1368 static Rune left3[] =  { '\'', '"', '`', 0 };
1369 
1370 Rune *left[] = {
1371 	left1,
1372 	left2,
1373 	left3,
1374 	nil
1375 };
1376 Rune *right[] = {
1377 	right1,
1378 	left2,
1379 	left3,
1380 	nil
1381 };
1382 
1383 void
1384 wdoubleclick(Window *w, uint *q0, uint *q1)
1385 {
1386 	int c, i;
1387 	Rune *r, *l, *p;
1388 	uint q;
1389 
1390 	for(i=0; left[i]!=nil; i++){
1391 		q = *q0;
1392 		l = left[i];
1393 		r = right[i];
1394 		/* try matching character to left, looking right */
1395 		if(q == 0)
1396 			c = '\n';
1397 		else
1398 			c = w->r[q-1];
1399 		p = strrune(l, c);
1400 		if(p != nil){
1401 			if(wclickmatch(w, c, r[p-l], 1, &q))
1402 				*q1 = q-(c!='\n');
1403 			return;
1404 		}
1405 		/* try matching character to right, looking left */
1406 		if(q == w->nr)
1407 			c = '\n';
1408 		else
1409 			c = w->r[q];
1410 		p = strrune(r, c);
1411 		if(p != nil){
1412 			if(wclickmatch(w, c, l[p-r], -1, &q)){
1413 				*q1 = *q0+(*q0<w->nr && c=='\n');
1414 				*q0 = q;
1415 				if(c!='\n' || q!=0 || w->r[0]=='\n')
1416 					(*q0)++;
1417 			}
1418 			return;
1419 		}
1420 	}
1421 	/* try filling out word to right */
1422 	while(*q1<w->nr && isalnum(w->r[*q1]))
1423 		(*q1)++;
1424 	/* try filling out word to left */
1425 	while(*q0>0 && isalnum(w->r[*q0-1]))
1426 		(*q0)--;
1427 }
1428 
1429 int
1430 wclickmatch(Window *w, int cl, int cr, int dir, uint *q)
1431 {
1432 	Rune c;
1433 	int nest;
1434 
1435 	nest = 1;
1436 	for(;;){
1437 		if(dir > 0){
1438 			if(*q == w->nr)
1439 				break;
1440 			c = w->r[*q];
1441 			(*q)++;
1442 		}else{
1443 			if(*q == 0)
1444 				break;
1445 			(*q)--;
1446 			c = w->r[*q];
1447 		}
1448 		if(c == cr){
1449 			if(--nest==0)
1450 				return 1;
1451 		}else if(c == cl)
1452 			nest++;
1453 	}
1454 	return cl=='\n' && nest==1;
1455 }
1456 
1457 
1458 uint
1459 wbacknl(Window *w, uint p, uint n)
1460 {
1461 	int i, j;
1462 
1463 	/* look for start of this line if n==0 */
1464 	if(n==0 && p>0 && w->r[p-1]!='\n')
1465 		n = 1;
1466 	i = n;
1467 	while(i-->0 && p>0){
1468 		--p;	/* it's at a newline now; back over it */
1469 		if(p == 0)
1470 			break;
1471 		/* at 128 chars, call it a line anyway */
1472 		for(j=128; --j>0 && p>0; p--)
1473 			if(w->r[p-1]=='\n')
1474 				break;
1475 	}
1476 	return p;
1477 }
1478 
1479 void
1480 wshow(Window *w, uint q0)
1481 {
1482 	int qe;
1483 	int nl;
1484 	uint q;
1485 
1486 	qe = w->org+w->f.nchars;
1487 	if(w->org<=q0 && (q0<qe || (q0==qe && qe==w->nr)))
1488 		wscrdraw(w);
1489 	else{
1490 		nl = 4*w->f.maxlines/5;
1491 		q = wbacknl(w, q0, nl);
1492 		/* avoid going backwards if trying to go forwards - long lines! */
1493 		if(!(q0>w->org && q<w->org))
1494 			wsetorigin(w, q, TRUE);
1495 		while(q0 > w->org+w->f.nchars)
1496 			wsetorigin(w, w->org+1, FALSE);
1497 	}
1498 }
1499 
1500 void
1501 wsetorigin(Window *w, uint org, int exact)
1502 {
1503 	int i, a, fixup;
1504 	Rune *r;
1505 	uint n;
1506 
1507 	if(org>0 && !exact){
1508 		/* org is an estimate of the char posn; find a newline */
1509 		/* don't try harder than 256 chars */
1510 		for(i=0; i<256 && org<w->nr; i++){
1511 			if(w->r[org] == '\n'){
1512 				org++;
1513 				break;
1514 			}
1515 			org++;
1516 		}
1517 	}
1518 	a = org-w->org;
1519 	fixup = 0;
1520 	if(a>=0 && a<w->f.nchars){
1521 		frdelete(&w->f, 0, a);
1522 		fixup = 1;	/* frdelete can leave end of last line in wrong selection mode; it doesn't know what follows */
1523 	}else if(a<0 && -a<w->f.nchars){
1524 		n = w->org - org;
1525 		r = runemalloc(n);
1526 		runemove(r, w->r+org, n);
1527 		frinsert(&w->f, r, r+n, 0);
1528 		free(r);
1529 	}else
1530 		frdelete(&w->f, 0, w->f.nchars);
1531 	w->org = org;
1532 	wfill(w);
1533 	wscrdraw(w);
1534 	wsetselect(w, w->q0, w->q1);
1535 	if(fixup && w->f.p1 > w->f.p0)
1536 		frdrawsel(&w->f, frptofchar(&w->f, w->f.p1-1), w->f.p1-1, w->f.p1, 1);
1537 }
1538 
1539 void
1540 wsetselect(Window *w, uint q0, uint q1)
1541 {
1542 	int p0, p1;
1543 
1544 	/* w->f.p0 and w->f.p1 are always right; w->q0 and w->q1 may be off */
1545 	w->q0 = q0;
1546 	w->q1 = q1;
1547 	/* compute desired p0,p1 from q0,q1 */
1548 	p0 = q0-w->org;
1549 	p1 = q1-w->org;
1550 	if(p0 < 0)
1551 		p0 = 0;
1552 	if(p1 < 0)
1553 		p1 = 0;
1554 	if(p0 > w->f.nchars)
1555 		p0 = w->f.nchars;
1556 	if(p1 > w->f.nchars)
1557 		p1 = w->f.nchars;
1558 	if(p0==w->f.p0 && p1==w->f.p1)
1559 		return;
1560 	/* screen disagrees with desired selection */
1561 	if(w->f.p1<=p0 || p1<=w->f.p0 || p0==p1 || w->f.p1==w->f.p0){
1562 		/* no overlap or too easy to bother trying */
1563 		frdrawsel(&w->f, frptofchar(&w->f, w->f.p0), w->f.p0, w->f.p1, 0);
1564 		frdrawsel(&w->f, frptofchar(&w->f, p0), p0, p1, 1);
1565 		goto Return;
1566 	}
1567 	/* overlap; avoid unnecessary painting */
1568 	if(p0 < w->f.p0){
1569 		/* extend selection backwards */
1570 		frdrawsel(&w->f, frptofchar(&w->f, p0), p0, w->f.p0, 1);
1571 	}else if(p0 > w->f.p0){
1572 		/* trim first part of selection */
1573 		frdrawsel(&w->f, frptofchar(&w->f, w->f.p0), w->f.p0, p0, 0);
1574 	}
1575 	if(p1 > w->f.p1){
1576 		/* extend selection forwards */
1577 		frdrawsel(&w->f, frptofchar(&w->f, w->f.p1), w->f.p1, p1, 1);
1578 	}else if(p1 < w->f.p1){
1579 		/* trim last part of selection */
1580 		frdrawsel(&w->f, frptofchar(&w->f, p1), p1, w->f.p1, 0);
1581 	}
1582 
1583     Return:
1584 	w->f.p0 = p0;
1585 	w->f.p1 = p1;
1586 }
1587 
1588 uint
1589 winsert(Window *w, Rune *r, int n, uint q0)
1590 {
1591 	uint m;
1592 
1593 	if(n == 0)
1594 		return q0;
1595 	if(w->nr+n>HiWater && q0>=w->org && q0>=w->qh){
1596 		m = min(HiWater-LoWater, min(w->org, w->qh));
1597 		w->org -= m;
1598 		w->qh -= m;
1599 		if(w->q0 > m)
1600 			w->q0 -= m;
1601 		else
1602 			w->q0 = 0;
1603 		if(w->q1 > m)
1604 			w->q1 -= m;
1605 		else
1606 			w->q1 = 0;
1607 		w->nr -= m;
1608 		runemove(w->r, w->r+m, w->nr);
1609 		q0 -= m;
1610 	}
1611 	if(w->nr+n > w->maxr){
1612 		/*
1613 		 * Minimize realloc breakage:
1614 		 *	Allocate at least MinWater
1615 		 * 	Double allocation size each time
1616 		 *	But don't go much above HiWater
1617 		 */
1618 		m = max(min(2*(w->nr+n), HiWater), w->nr+n)+MinWater;
1619 		if(m > HiWater)
1620 			m = max(HiWater+MinWater, w->nr+n);
1621 		if(m > w->maxr){
1622 			w->r = runerealloc(w->r, m);
1623 			w->maxr = m;
1624 		}
1625 	}
1626 	runemove(w->r+q0+n, w->r+q0, w->nr-q0);
1627 	runemove(w->r+q0, r, n);
1628 	w->nr += n;
1629 	/* if output touches, advance selection, not qh; works best for keyboard and output */
1630 	if(q0 <= w->q1)
1631 		w->q1 += n;
1632 	if(q0 <= w->q0)
1633 		w->q0 += n;
1634 	if(q0 < w->qh)
1635 		w->qh += n;
1636 	if(q0 < w->iq1)
1637 		w->iq1 += n;
1638 	if(q0 < w->org)
1639 		w->org += n;
1640 	else if(q0 <= w->org+w->f.nchars)
1641 		frinsert(&w->f, r, r+n, q0-w->org);
1642 	return q0;
1643 }
1644 
1645 void
1646 wfill(Window *w)
1647 {
1648 	Rune *rp;
1649 	int i, n, m, nl;
1650 
1651 	if(w->f.lastlinefull)
1652 		return;
1653 	rp = malloc(messagesize);
1654 	do{
1655 		n = w->nr-(w->org+w->f.nchars);
1656 		if(n == 0)
1657 			break;
1658 		if(n > 2000)	/* educated guess at reasonable amount */
1659 			n = 2000;
1660 		runemove(rp, w->r+(w->org+w->f.nchars), n);
1661 		/*
1662 		 * it's expensive to frinsert more than we need, so
1663 		 * count newlines.
1664 		 */
1665 		nl = w->f.maxlines-w->f.nlines;
1666 		m = 0;
1667 		for(i=0; i<n; ){
1668 			if(rp[i++] == '\n'){
1669 				m++;
1670 				if(m >= nl)
1671 					break;
1672 			}
1673 		}
1674 		frinsert(&w->f, rp, rp+i, w->f.nchars);
1675 	}while(w->f.lastlinefull == FALSE);
1676 	free(rp);
1677 }
1678 
1679 char*
1680 wcontents(Window *w, int *ip)
1681 {
1682 	return runetobyte(w->r, w->nr, ip);
1683 }