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Date:: Tue May 23 03:55:45 2006 UTC
Message:: fix _screen leak
Actions:: History | Blame | Raw File
1 /*
2  * Some of the stuff in this file is not X-dependent and should be elsewhere.
3  */
4 #include <u.h>
5 #include "x11-inc.h"
6 #include <libc.h>
7 #include <draw.h>
8 #include <memdraw.h>
9 #include <keyboard.h>
10 #include <mouse.h>
11 #include <cursor.h>
12 #include "x11-memdraw.h"
13 
14 char *winsize;
15 static int parsewinsize(char*, Rectangle*, int*);
16 
17 static Memimage	*xattach(char*);
18 static void	plan9cmap(void);
19 static int	setupcmap(XWindow);
20 static int	xreplacescreenimage(void);
21 static XGC	xgc(XDrawable, int, int);
22 static Image	*getimage0(Display*, Image*);
23 
24 Xprivate _x;
25 
26 Display*
27 _initdisplay(void (*error)(Display*, char*), char *label)
28 {
29 	Display *d;
30 	Memimage *m;
31 
32 	/*
33 	 * This rfork(RFNOTEG) isn't exactly right,
34 	 * but we need some way to signal window 
35 	 * closes.  Right now we post a hangup
36 	 * note to the note group, which kills a whole
37 	 * lot more than just the current program
38 	 * if we don't do this.
39 	 */
40 	/*
41 	 * Actually, I don't know what I changed but
42 	 * this appears not to be necessary anymore.
43 	 * I'll regret this probably.
44 	rfork(RFNOTEG);
45 	*/
46 	memimageinit();
47 
48 	d = mallocz(sizeof(Display), 1);
49 	if(d == nil)
50 		return nil;
51 
52 	d->buf = malloc(16000+5);
53 	d->obuf = malloc(16000);
54 	if(d->buf == nil || d->obuf == nil){
55 		free(d->buf);
56 		free(d->obuf);
57 		free(d);
58 		return nil;
59 	}
60 	d->bufsize = 16000;
61 	d->obufsize = 16000;
62 	d->bufp = d->buf;
63 	d->obufp = d->obuf;
64 
65 	m = xattach(label);
66 	if(m == nil){
67 		free(d);
68 		return nil;
69 	}
70 
71 	d->error = error;
72 	_initdisplaymemimage(d, m);
73 	d->image = getimage0(d, 0);
74 	
75 	return d;
76 }
77 
78 static Image*
79 getimage0(Display *d, Image *image)
80 {
81 	char info[12*12+1];
82 	uchar *a;
83 	int n;
84 	extern int _freeimage1(Image*);
85 
86 	/*
87 	 * If there's an old screen, it has id 0.  The 'J' request below
88 	 * will try to install the new screen as id 0, so the old one 
89 	 * must be freed first.
90 	 */
91 	if(image){
92 		_freeimage1(image);
93 		memset(image, 0, sizeof(Image));
94 	}
95 
96 	a = bufimage(d, 2);
97 	a[0] = 'J';
98 	a[1] = 'I';
99 	if(flushimage(d, 0) < 0){
100 		fprint(2, "cannot read screen info: %r\n");
101 		abort();
102 	}
103 
104 	n = _drawmsgread(d, info, sizeof info);
105 	if(n != 12*12){
106 		fprint(2, "short screen info\n");
107 		abort();
108 	}
109 
110 	if(image == nil){
111 		image = mallocz(sizeof(Image), 1);
112 		if(image == nil){
113 			fprint(2, "cannot allocate image: %r\n");
114 			abort();
115 		}
116 	}
117 
118 	image->display = d;
119 	image->id = 0;
120 	image->chan = strtochan(info+2*12);
121 	image->depth = chantodepth(image->chan);
122 	image->repl = atoi(info+3*12);
123 	image->r.min.x = atoi(info+4*12);
124 	image->r.min.y = atoi(info+5*12);
125 	image->r.max.x = atoi(info+6*12);
126 	image->r.max.y = atoi(info+7*12);
127 	image->clipr.min.x = atoi(info+8*12);
128 	image->clipr.min.y = atoi(info+9*12);
129 	image->clipr.max.x = atoi(info+10*12);
130 	image->clipr.max.y = atoi(info+11*12);
131 	return image;
132 }
133 
134 int
135 getwindow(Display *d, int ref)
136 {
137 	Image *i;
138 	Image *oi;
139 
140 	if(_x.destroyed){
141 		postnote(PNGROUP, getpgrp(), "hangup");
142 		return -1;
143 	}
144 	if(xreplacescreenimage() == 0)
145 		return 0;
146 
147 	/*
148 	 * Libdraw promises not to change the value of "screen",
149 	 * so we have to reuse the image structure
150 	 * memory we already have.
151 	 */
152 	oi = d->image;
153 	i = getimage0(d, oi);
154 	d->image = i;
155 	/* fprint(2, "getwindow %p -> %p\n", oi, i); */
156 
157 	freescreen(_screen);
158 	_screen = allocscreen(i, d->white, 0);
159 	_freeimage1(screen);
160 	screen = _allocwindow(screen, _screen, i->r, ref, DWhite);
161 	d->screenimage = screen;
162 	return 0;
163 }
164 
165 static int
166 xerror(XDisplay *d, XErrorEvent *e)
167 {
168 	char buf[200];
169 
170 	if(e->request_code == 42) /* XSetInputFocus */
171 		return 0;
172 	if(e->request_code == 18) /* XChangeProperty */
173 		return 0;
174 
175 	print("X error: error_code=%d, request_code=%d, minor=%d disp=%p\n",
176 		e->error_code, e->request_code, e->minor_code, d);
177 	XGetErrorText(d, e->error_code, buf, sizeof buf);
178 	print("%s\n", buf);
179 	return 0;
180 }
181 
182 static int
183 xioerror(XDisplay *d)
184 {
185 	/*print("X I/O error\n"); */
186 	sysfatal("X I/O error\n");
187 	abort();
188 	return -1;
189 }
190 
191 
192 static Memimage*
193 xattach(char *label)
194 {
195 	char *argv[2], *disp;
196 	int i, havemin, height, mask, n, width, x, xrootid, y;
197 	Rectangle r;
198 	XClassHint classhint;
199 	XDrawable pmid;
200 	XPixmapFormatValues *pfmt;
201 	XScreen *xscreen;
202 	XSetWindowAttributes attr;
203 	XSizeHints normalhint;
204 	XTextProperty name;
205 	XVisualInfo xvi;
206 	XWindow xrootwin;
207 	XWindowAttributes wattr;
208 	XWMHints hint;
209 	Atom atoms[2];
210 
211 	/*
212 	if(XInitThreads() == 0){
213 		fprint(2, "XInitThreads failed\n");
214 		abort();
215 	}
216 	*/
217 
218 	/*
219 	 * Connect to X server.
220 	 */
221 	_x.display = XOpenDisplay(NULL);
222 	if(_x.display == nil){
223 		disp = getenv("DISPLAY");
224 		werrstr("XOpenDisplay %s: %r", disp ? disp : ":0");
225 		free(disp);
226 		return nil;
227 	}
228 	XSetErrorHandler(xerror);
229 	XSetIOErrorHandler(xioerror);
230 	xrootid = DefaultScreen(_x.display);
231 	xrootwin = DefaultRootWindow(_x.display);
232 
233 	/* 
234 	 * Figure out underlying screen format.
235 	 */
236 	if(XMatchVisualInfo(_x.display, xrootid, 16, TrueColor, &xvi)
237 	|| XMatchVisualInfo(_x.display, xrootid, 16, DirectColor, &xvi)){
238 		_x.vis = xvi.visual;
239 		_x.depth = 16;
240 	}
241 	else
242 	if(XMatchVisualInfo(_x.display, xrootid, 15, TrueColor, &xvi)
243 	|| XMatchVisualInfo(_x.display, xrootid, 15, DirectColor, &xvi)){
244 		_x.vis = xvi.visual;
245 		_x.depth = 15;
246 	}
247 	else
248 	if(XMatchVisualInfo(_x.display, xrootid, 24, TrueColor, &xvi)
249 	|| XMatchVisualInfo(_x.display, xrootid, 24, DirectColor, &xvi)){
250 		_x.vis = xvi.visual;
251 		_x.depth = 24;
252 	}
253 	else
254 	if(XMatchVisualInfo(_x.display, xrootid, 8, PseudoColor, &xvi)
255 	|| XMatchVisualInfo(_x.display, xrootid, 8, StaticColor, &xvi)){
256 		if(_x.depth > 8){
257 			werrstr("can't deal with colormapped depth %d screens",
258 				_x.depth);
259 			goto err0;
260 		}
261 		_x.vis = xvi.visual;
262 		_x.depth = 8;
263 	}
264 	else{
265 		_x.depth = DefaultDepth(_x.display, xrootid);
266 		if(_x.depth != 8){
267 			werrstr("can't understand depth %d screen", _x.depth);
268 			goto err0;
269 		}
270 		_x.vis = DefaultVisual(_x.display, xrootid);
271 	}
272 
273 	if(DefaultDepth(_x.display, xrootid) == _x.depth)
274 		_x.usetable = 1;
275 
276 	/*
277 	 * _x.depth is only the number of significant pixel bits,
278 	 * not the total number of pixel bits.  We need to walk the
279 	 * display list to find how many actual bits are used
280 	 * per pixel.
281 	 */
282 	_x.chan = 0;
283 	pfmt = XListPixmapFormats(_x.display, &n);
284 	for(i=0; i<n; i++){
285 		if(pfmt[i].depth == _x.depth){
286 			switch(pfmt[i].bits_per_pixel){
287 			case 1:	/* untested */
288 				_x.chan = GREY1;
289 				break;
290 			case 2:	/* untested */
291 				_x.chan = GREY2;
292 				break;
293 			case 4:	/* untested */
294 				_x.chan = GREY4;
295 				break;
296 			case 8:
297 				_x.chan = CMAP8;
298 				break;
299 			case 15:
300 				_x.chan = RGB15;
301 				break;
302 			case 16: /* how to tell RGB15? */
303 				_x.chan = RGB16;
304 				break;
305 			case 24: /* untested (impossible?) */
306 				_x.chan = RGB24;
307 				break;
308 			case 32:
309 				_x.chan = XRGB32;
310 				break;
311 			}
312 		}
313 	}
314 	if(_x.chan == 0){
315 		werrstr("could not determine screen pixel format");
316 		goto err0;
317 	}
318 
319 	/*
320 	 * Set up color map if necessary.
321 	 */
322 	xscreen = DefaultScreenOfDisplay(_x.display);
323 	_x.cmap = DefaultColormapOfScreen(xscreen);
324 	if(_x.vis->class != StaticColor){
325 		plan9cmap();
326 		setupcmap(xrootwin);
327 	}
328 
329 	/*
330 	 * We get to choose the initial rectangle size.
331 	 * This is arbitrary.  In theory we should read the
332 	 * command line and allow the traditional X options.
333 	 */
334 	mask = 0;
335 	x = 0;
336 	y = 0;
337 	if(winsize){
338 		if(parsewinsize(winsize, &r, &havemin) < 0)
339 			sysfatal("%r");
340 	}else{
341 		/*
342 		 * Parse the various X resources.  Thanks to Peter Canning.
343 		 */
344 		char *screen_resources, *display_resources, *geom, 
345 			*geomrestype, *home, *file;
346 		XrmDatabase database;
347 		XrmValue geomres;
348 
349 		database = XrmGetDatabase(_x.display);
350 		screen_resources = XScreenResourceString(xscreen);
351 		if(screen_resources != nil){
352 			XrmCombineDatabase(XrmGetStringDatabase(screen_resources), &database, False);
353 			XFree(screen_resources);
354 		}
355 
356 		display_resources = XResourceManagerString(_x.display);
357 		if(display_resources == nil){
358 			home = getenv("HOME");
359 			if(home!=nil && (file=smprint("%s/.Xdefaults", home)) != nil){
360 				XrmCombineFileDatabase(file, &database, False);
361 				free(file);
362 			}
363 			free(home);
364 		}else
365 			XrmCombineDatabase(XrmGetStringDatabase(display_resources), &database, False);
366 
367 		geom = smprint("%s.geometry", label);
368 		if(geom && XrmGetResource(database, geom, nil, &geomrestype, &geomres))
369 			mask = XParseGeometry(geomres.addr, &x, &y, (uint*)&width, (uint*)&height);
370 		free(geom);
371 
372 		if((mask & WidthValue) && (mask & HeightValue)){
373 			r = Rect(0, 0, width, height);
374 		}else{
375 			r = Rect(0, 0, WidthOfScreen(xscreen)*3/4,
376 					HeightOfScreen(xscreen)*3/4);
377 			if(Dx(r) > Dy(r)*3/2)
378 				r.max.x = r.min.x + Dy(r)*3/2;
379 			if(Dy(r) > Dx(r)*3/2)
380 				r.max.y = r.min.y + Dx(r)*3/2;
381 		}
382 		if(mask & XNegative){
383 			x += WidthOfScreen(xscreen);
384 		}
385 		if(mask & YNegative){
386 			y += HeightOfScreen(xscreen);
387 		}
388 		havemin = 0;
389 	}
390 
391 	memset(&attr, 0, sizeof attr);
392 	attr.colormap = _x.cmap;
393 	attr.background_pixel = ~0;
394 	attr.border_pixel = 0;
395 	_x.drawable = XCreateWindow(
396 		_x.display,	/* display */
397 		xrootwin,	/* parent */
398 		x,		/* x */
399 		y,		/* y */
400 		Dx(r),		/* width */
401 	 	Dy(r),		/* height */
402 		0,		/* border width */
403 		_x.depth,	/* depth */
404 		InputOutput,	/* class */
405 		_x.vis,		/* visual */
406 				/* valuemask */
407 		CWBackPixel|CWBorderPixel|CWColormap,
408 		&attr		/* attributes (the above aren't?!) */
409 	);
410 
411 	/*
412 	 * Label and other properties required by ICCCCM.
413 	 */
414 	memset(&name, 0, sizeof name);
415 	if(label == nil)
416 		label = "pjw-face-here";
417 	name.value = (uchar*)label;
418 	name.encoding = XA_STRING;
419 	name.format = 8;
420 	name.nitems = strlen((char*)name.value);
421 
422 	memset(&normalhint, 0, sizeof normalhint);
423 	normalhint.flags = PSize|PMaxSize;
424 	if(winsize){
425 		normalhint.flags &= ~PSize;
426 		normalhint.flags |= USSize;
427 		normalhint.width = Dx(r);
428 		normalhint.height = Dy(r);
429 	}else{
430 		if((mask & WidthValue) && (mask & HeightValue)){
431 			normalhint.flags &= ~PSize;
432 			normalhint.flags |= USSize;
433 			normalhint.width = width;
434 			normalhint.height = height;
435 		}
436 		if((mask & WidthValue) && (mask & HeightValue)){
437 			normalhint.flags |= USPosition;
438 			normalhint.x = x;
439 			normalhint.y = y;
440 		}
441 	}
442 
443 	normalhint.max_width = WidthOfScreen(xscreen);
444 	normalhint.max_height = HeightOfScreen(xscreen);
445 
446 	memset(&hint, 0, sizeof hint);
447 	hint.flags = InputHint|StateHint;
448 	hint.input = 1;
449 	hint.initial_state = NormalState;
450 
451 	memset(&classhint, 0, sizeof classhint);
452 	classhint.res_name = label;
453 	classhint.res_class = label;
454 
455 	argv[0] = label;
456 	argv[1] = nil;
457 
458 	XSetWMProperties(
459 		_x.display,	/* display */
460 		_x.drawable,	/* window */
461 		&name,		/* XA_WM_NAME property */
462 		&name,		/* XA_WM_ICON_NAME property */
463 		argv,		/* XA_WM_COMMAND */
464 		1,		/* argc */
465 		&normalhint,	/* XA_WM_NORMAL_HINTS */
466 		&hint,		/* XA_WM_HINTS */
467 		&classhint	/* XA_WM_CLASSHINTS */
468 	);
469 	XFlush(_x.display);
470 
471 	if(havemin){
472 		XWindowChanges ch;
473 
474 		memset(&ch, 0, sizeof ch);
475 		ch.x = r.min.x;
476 		ch.y = r.min.y;
477 		XConfigureWindow(_x.display, _x.drawable, CWX|CWY, &ch);
478 		/*
479 		 * Must pretend origin is 0,0 for X.
480 		 */
481 		r = Rect(0,0,Dx(r),Dy(r));
482 	}
483 	/*
484 	 * Look up clipboard atom.
485 	 */
486 	_x.clipboard = XInternAtom(_x.display, "CLIPBOARD", False);
487 	_x.utf8string = XInternAtom(_x.display, "UTF8_STRING", False);
488 	_x.targets = XInternAtom(_x.display, "TARGETS", False);
489 	_x.text = XInternAtom(_x.display, "TEXT", False);
490 	_x.compoundtext = XInternAtom(_x.display, "COMPOUND_TEXT", False);
491 	_x.takefocus = XInternAtom(_x.display, "WM_TAKE_FOCUS", False);
492 	_x.losefocus = XInternAtom(_x.display, "_9WM_LOSE_FOCUS", False);
493 	_x.wmprotos = XInternAtom(_x.display, "WM_PROTOCOLS", False);
494 
495 	atoms[0] = _x.takefocus;
496 	atoms[1] = _x.losefocus;
497 	XChangeProperty(_x.display, _x.drawable, _x.wmprotos, XA_ATOM, 32,
498 		PropModeReplace, (uchar*)atoms, 2);
499 
500 	/*
501 	 * Put the window on the screen, check to see what size we actually got.
502 	 */
503 	XMapWindow(_x.display, _x.drawable);
504 	XSync(_x.display, False);
505 
506 	if(!XGetWindowAttributes(_x.display, _x.drawable, &wattr))
507 		fprint(2, "XGetWindowAttributes failed\n");
508 	else if(wattr.width && wattr.height){
509 		if(wattr.width != Dx(r) || wattr.height != Dy(r)){
510 			r.max.x = wattr.width;
511 			r.max.y = wattr.height;
512 		}
513 	}else
514 		fprint(2, "XGetWindowAttributes: bad attrs\n");
515 
516 	/*
517 	 * Allocate our local backing store.
518 	 */
519 	_x.screenr = r;
520 	_x.screenpm = XCreatePixmap(_x.display, _x.drawable, Dx(r), Dy(r), _x.depth);
521 	_x.nextscreenpm = _x.screenpm;
522 	_x.screenimage = _xallocmemimage(r, _x.chan, _x.screenpm);
523 
524 	/*
525 	 * Allocate some useful graphics contexts for the future.
526 	 */
527 	_x.gcfill	= xgc(_x.screenpm, FillSolid, -1);
528 	_x.gccopy	= xgc(_x.screenpm, -1, -1);
529 	_x.gcsimplesrc 	= xgc(_x.screenpm, FillStippled, -1);
530 	_x.gczero	= xgc(_x.screenpm, -1, -1);
531 	_x.gcreplsrc	= xgc(_x.screenpm, FillTiled, -1);
532 
533 	pmid = XCreatePixmap(_x.display, _x.drawable, 1, 1, 1);
534 	_x.gcfill0	= xgc(pmid, FillSolid, 0);
535 	_x.gccopy0	= xgc(pmid, -1, -1);
536 	_x.gcsimplesrc0	= xgc(pmid, FillStippled, -1);
537 	_x.gczero0	= xgc(pmid, -1, -1);
538 	_x.gcreplsrc0	= xgc(pmid, FillTiled, -1);
539 	XFreePixmap(_x.display, pmid);
540 
541 	/*
542 	 * Lots of display connections for various procs.
543 	 */
544 	_x.kbdcon	= XOpenDisplay(NULL);
545 	_x.mousecon	= XOpenDisplay(NULL);
546 	_x.snarfcon	= XOpenDisplay(NULL);
547 
548 	if(0) fprint(2, "x: display=%p kbd=%p mouse=%p snarf=%p\n",
549 		_x.display, _x.kbdcon, _x.mousecon, _x.snarfcon);
550 
551 	return _x.screenimage;
552 
553 err0:
554 	/*
555 	 * Should do a better job of cleaning up here.
556 	 */
557 	XCloseDisplay(_x.display);
558 	return nil;
559 }
560 
561 int
562 drawsetlabel(char *label)
563 {
564 	XTextProperty name;
565 
566 	/*
567 	 * Label and other properties required by ICCCCM.
568 	 */
569 	memset(&name, 0, sizeof name);
570 	if(label == nil)
571 		label = "pjw-face-here";
572 	name.value = (uchar*)label;
573 	name.encoding = XA_STRING;
574 	name.format = 8;
575 	name.nitems = strlen((char*)name.value);
576 
577 	XSetWMProperties(
578 		_x.display,	/* display */
579 		_x.drawable,	/* window */
580 		&name,		/* XA_WM_NAME property */
581 		&name,		/* XA_WM_ICON_NAME property */
582 		nil,		/* XA_WM_COMMAND */
583 		0,		/* argc */
584 		nil,		/* XA_WM_NORMAL_HINTS */
585 		nil,		/* XA_WM_HINTS */
586 		nil	/* XA_WM_CLASSHINTS */
587 	);
588 	XFlush(_x.display);
589 	return 0;
590 }
591 
592 /*
593  * Create a GC with a particular fill style and XXX.
594  * Disable generation of GraphicsExpose/NoExpose events in the GC.
595  */
596 static XGC
597 xgc(XDrawable d, int fillstyle, int foreground)
598 {
599 	XGC gc;
600 	XGCValues v;
601 
602 	memset(&v, 0, sizeof v);
603 	v.function = GXcopy;
604 	v.graphics_exposures = False;
605 	gc = XCreateGC(_x.display, d, GCFunction|GCGraphicsExposures, &v);
606 	if(fillstyle != -1)
607 		XSetFillStyle(_x.display, gc, fillstyle);
608 	if(foreground != -1)
609 		XSetForeground(_x.display, gc, 0);
610 	return gc;
611 }
612 
613 
614 /*
615  * Initialize map with the Plan 9 rgbv color map.
616  */
617 static void
618 plan9cmap(void)
619 {
620 	int r, g, b, cr, cg, cb, v, num, den, idx, v7, idx7;
621 	static int once;
622 
623 	if(once)
624 		return;
625 	once = 1;
626 
627 	for(r=0; r!=4; r++)
628 	for(g = 0; g != 4; g++)
629 	for(b = 0; b!=4; b++)
630 	for(v = 0; v!=4; v++){
631 		den=r;
632 		if(g > den)
633 			den=g;
634 		if(b > den)
635 			den=b;
636 		/* divide check -- pick grey shades */
637 		if(den==0)
638 			cr=cg=cb=v*17;
639 		else {
640 			num=17*(4*den+v);
641 			cr=r*num/den;
642 			cg=g*num/den;
643 			cb=b*num/den;
644 		}
645 		idx = r*64 + v*16 + ((g*4 + b + v - r) & 15);
646 		_x.map[idx].red = cr*0x0101;
647 		_x.map[idx].green = cg*0x0101;
648 		_x.map[idx].blue = cb*0x0101;
649 		_x.map[idx].pixel = idx;
650 		_x.map[idx].flags = DoRed|DoGreen|DoBlue;
651 
652 		v7 = v >> 1;
653 		idx7 = r*32 + v7*16 + g*4 + b;
654 		if((v & 1) == v7){
655 			_x.map7to8[idx7][0] = idx;
656 			if(den == 0) { 		/* divide check -- pick grey shades */
657 				cr = ((255.0/7.0)*v7)+0.5;
658 				cg = cr;
659 				cb = cr;
660 			}
661 			else {
662 				num=17*15*(4*den+v7*2)/14;
663 				cr=r*num/den;
664 				cg=g*num/den;
665 				cb=b*num/den;
666 			}
667 			_x.map7[idx7].red = cr*0x0101;
668 			_x.map7[idx7].green = cg*0x0101;
669 			_x.map7[idx7].blue = cb*0x0101;
670 			_x.map7[idx7].pixel = idx7;
671 			_x.map7[idx7].flags = DoRed|DoGreen|DoBlue;
672 		}
673 		else
674 			_x.map7to8[idx7][1] = idx;
675 	}
676 }
677 
678 /*
679  * Initialize and install the rgbv color map as a private color map
680  * for this application.  It gets the best colors when it has the
681  * cursor focus.
682  *
683  * We always choose the best depth possible, but that might not
684  * be the default depth.  On such "suboptimal" systems, we have to allocate an
685  * empty color map anyway, according to Axel Belinfante.
686  */
687 static int 
688 setupcmap(XWindow w)
689 {
690 	char buf[30];
691 	int i;
692 	u32int p, pp;
693 	XColor c;
694 
695 	if(_x.depth <= 1)
696 		return 0;
697 
698 	if(_x.depth >= 24) {
699 		if(_x.usetable == 0)
700 			_x.cmap = XCreateColormap(_x.display, w, _x.vis, AllocNone); 
701 
702 		/*
703 		 * The pixel value returned from XGetPixel needs to
704 		 * be converted to RGB so we can call rgb2cmap()
705 		 * to translate between 24 bit X and our color. Unfortunately,
706 		 * the return value appears to be display server endian 
707 		 * dependant. Therefore, we run some heuristics to later
708 		 * determine how to mask the int value correctly.
709 		 * Yeah, I know we can look at _x.vis->byte_order but 
710 		 * some displays say MSB even though they run on LSB.
711 		 * Besides, this is more anal.
712 		 */
713 		c = _x.map[19];	/* known to have different R, G, B values */
714 		if(!XAllocColor(_x.display, _x.cmap, &c)){
715 			werrstr("XAllocColor: %r");
716 			return -1;
717 		}
718 		p  = c.pixel;
719 		pp = rgb2cmap((p>>16)&0xff,(p>>8)&0xff,p&0xff);
720 		if(pp != _x.map[19].pixel) {
721 			/* check if endian is other way */
722 			pp = rgb2cmap(p&0xff,(p>>8)&0xff,(p>>16)&0xff);
723 			if(pp != _x.map[19].pixel){
724 				werrstr("cannot detect X server byte order");
725 				return -1;
726 			}
727 
728 			switch(_x.chan){
729 			case RGB24:
730 				_x.chan = BGR24;
731 				break;
732 			case XRGB32:
733 				_x.chan = XBGR32;
734 				break;
735 			default:
736 				werrstr("cannot byteswap channel %s",
737 					chantostr(buf, _x.chan));
738 				break;
739 			}
740 		}
741 	}else if(_x.vis->class == TrueColor || _x.vis->class == DirectColor){
742 		/*
743 		 * Do nothing.  We have no way to express a
744 		 * mixed-endian 16-bit screen, so pretend they don't exist.
745 		 */
746 		if(_x.usetable == 0)
747 			_x.cmap = XCreateColormap(_x.display, w, _x.vis, AllocNone);
748 	}else if(_x.vis->class == PseudoColor){
749 		if(_x.usetable == 0){
750 			_x.cmap = XCreateColormap(_x.display, w, _x.vis, AllocAll); 
751 			XStoreColors(_x.display, _x.cmap, _x.map, 256);
752 			for(i = 0; i < 256; i++){
753 				_x.tox11[i] = i;
754 				_x.toplan9[i] = i;
755 			}
756 		}else{
757 			for(i = 0; i < 128; i++){
758 				c = _x.map7[i];
759 				if(!XAllocColor(_x.display, _x.cmap, &c)){
760 					werrstr("can't allocate colors in 7-bit map");
761 					return -1;
762 				}
763 				_x.tox11[_x.map7to8[i][0]] = c.pixel;
764 				_x.tox11[_x.map7to8[i][1]] = c.pixel;
765 				_x.toplan9[c.pixel] = _x.map7to8[i][0];
766 			}
767 		}
768 	}else{
769 		werrstr("unsupported visual class %d", _x.vis->class);
770 		return -1;
771 	}
772 	return 0;
773 }
774 
775 void
776 _flushmemscreen(Rectangle r)
777 {
778 	if(_x.nextscreenpm != _x.screenpm){
779 		qlock(&_x.screenlock);
780 		XSync(_x.display, False);
781 		XFreePixmap(_x.display, _x.screenpm);
782 		_x.screenpm = _x.nextscreenpm;
783 		qunlock(&_x.screenlock);
784 	}
785 
786 	if(r.min.x >= r.max.x || r.min.y >= r.max.y)
787 		return;
788 	XCopyArea(_x.display, _x.screenpm, _x.drawable, _x.gccopy, r.min.x, r.min.y,
789 		Dx(r), Dy(r), r.min.x, r.min.y);
790 	XFlush(_x.display);
791 }
792 
793 void
794 _xexpose(XEvent *e, XDisplay *xd)
795 {
796 	XExposeEvent *xe;
797 	Rectangle r;
798 
799 	qlock(&_x.screenlock);
800 	if(_x.screenpm != _x.nextscreenpm){
801 		qunlock(&_x.screenlock);
802 		return;
803 	}
804 	xe = (XExposeEvent*)e;
805 	r.min.x = xe->x;
806 	r.min.y = xe->y;
807 	r.max.x = xe->x+xe->width;
808 	r.max.y = xe->y+xe->height;
809 	XCopyArea(xd, _x.screenpm, _x.drawable, _x.gccopy, r.min.x, r.min.y,
810 		Dx(r), Dy(r), r.min.x, r.min.y);
811 	XSync(xd, False);
812 	qunlock(&_x.screenlock);
813 }
814 
815 int
816 _xdestroy(XEvent *e, XDisplay *xd)
817 {
818 	XDestroyWindowEvent *xe;
819 
820 	xe = (XDestroyWindowEvent*)e;
821 	if(xe->window == _x.drawable){
822 		_x.destroyed = 1;
823 		return 1;
824 	}
825 	return 0;
826 }
827 
828 int
829 _xconfigure(XEvent *e, XDisplay *xd)
830 {
831 	Rectangle r;
832 	XConfigureEvent *xe = (XConfigureEvent*)e;
833 
834 	if(xe->width == Dx(_x.screenr) && xe->height == Dy(_x.screenr))
835 		return 0;
836 	if(xe->width==0 || xe->height==0)
837 		fprint(2, "ignoring resize to %dx%d\n", xe->width, xe->height);
838 	r = Rect(0, 0, xe->width, xe->height);
839 	qlock(&_x.screenlock);
840 	if(_x.screenpm != _x.nextscreenpm){
841 		XCopyArea(xd, _x.screenpm, _x.drawable, _x.gccopy, r.min.x, r.min.y,
842 			Dx(r), Dy(r), r.min.x, r.min.y);
843 		XSync(xd, False);
844 	}
845 	qunlock(&_x.screenlock);
846 	_x.newscreenr = r;
847 	return 1;
848 }
849 
850 static int
851 xreplacescreenimage(void)
852 {
853 	Memimage *m;
854 	XDrawable pixmap;
855 	Rectangle r;
856 
857 	r = _x.newscreenr;
858 	if(eqrect(_x.screenr, r))
859 		return 0;
860 
861 	pixmap = XCreatePixmap(_x.display, _x.drawable, Dx(r), Dy(r), _x.depth);
862 	m = _xallocmemimage(r, _x.chan, pixmap);
863 	if(_x.nextscreenpm != _x.screenpm)
864 		XFreePixmap(_x.display, _x.nextscreenpm);
865 	_x.nextscreenpm = pixmap;
866 	_x.screenr = r;
867 	_drawreplacescreenimage(m);
868 	return 1;
869 }
870 
871 static int
872 parsewinsize(char *s, Rectangle *r, int *havemin)
873 {
874 	char c, *os;
875 	int i, j, k, l;
876 
877 	os = s;
878 	*havemin = 0;
879 	*r = Rect(0,0,0,0);
880 	if(!isdigit((uchar)*s))
881 		goto oops;
882 	i = strtol(s, &s, 0);
883 	if(*s == 'x'){
884 		s++;
885 		if(!isdigit((uchar)*s))
886 			goto oops;
887 		j = strtol(s, &s, 0);
888 		r->max.x = i;
889 		r->max.y = j;
890 		if(*s == 0)
891 			return 0;
892 		if(*s != '@')
893 			goto oops;
894 
895 		s++;
896 		if(!isdigit((uchar)*s))
897 			goto oops;
898 		i = strtol(s, &s, 0);
899 		if(*s != ',' && *s != ' ')
900 			goto oops;
901 		s++;
902 		if(!isdigit((uchar)*s))
903 			goto oops;
904 		j = strtol(s, &s, 0);
905 		if(*s != 0)
906 			goto oops;
907 		*r = rectaddpt(*r, Pt(i,j));
908 		*havemin = 1;
909 		return 0;
910 	}
911 
912 	c = *s;
913 	if(c != ' ' && c != ',')
914 		goto oops;
915 	s++;
916 	if(!isdigit((uchar)*s))
917 		goto oops;
918 	j = strtol(s, &s, 0);
919 	if(*s != c)
920 		goto oops;
921 	s++;
922 	if(!isdigit((uchar)*s))
923 		goto oops;
924 	k = strtol(s, &s, 0);
925 	if(*s != c)
926 		goto oops;
927 	s++;
928 	if(!isdigit((uchar)*s))
929 		goto oops;
930 	l = strtol(s, &s, 0);
931 	if(*s != 0)
932 		goto oops;
933 	*r = Rect(i,j,k,l);
934 	*havemin = 1;
935 	return 0;
936 
937 oops:
938 	werrstr("bad syntax in window size '%s'", os);
939 	return -1;
940 }