1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 
5 Display	*display;
6 Font	*font;
7 Image	*screen;
8 int	_drawdebug;
9 
10 static char deffontname[] = "*default*";
11 Screen	*_screen;
12 
13 int		debuglockdisplay = 1;
14 
15 /*
16 static void
17 drawshutdown(void)
18 {
19 	Display *d;
20 
21 	d = display;
22 	if(d){
23 		display = nil;
24 		closedisplay(d);
25 	}
26 }
27 */
28 
29 int
30 initdraw(void (*error)(Display*, char*), char *fontname, char *label)
31 {
32 	Subfont *df;
33 	char buf[128];
34 
35 	display = _initdisplay(error, label); /* sets screen too */
36 	if(display == nil)
37 		return -1;
38 
39 	lockdisplay(display);
40 	display->screenimage = display->image;
41 
42 	/*
43 	 * Set up default font
44 	 */
45 	df = getdefont(display);
46 	display->defaultsubfont = df;
47 	if(df == nil){
48 		fprint(2, "imageinit: can't open default subfont: %r\n");
49     Error:
50 		closedisplay(display);
51 		display = nil;
52 		return -1;
53 	}
54 	if(fontname == nil)
55 		fontname = getenv("font");	/* leak */
56 
57 	/*
58 	 * Build fonts with caches==depth of screen, for speed.
59 	 * If conversion were faster, we'd use 0 and save memory.
60 	 */
61 	if(fontname == nil){
62 		snprint(buf, sizeof buf, "%d %d\n0 %d\t%s\n", df->height, df->ascent,
63 			df->n-1, deffontname);
64 /*BUG: Need something better for this	installsubfont("*default*", df); */
65 		font = buildfont(display, buf, deffontname);
66 		if(font == nil){
67 			fprint(2, "initdraw: can't open default font: %r\n");
68 			goto Error;
69 		}
70 	}else{
71 		font = openfont(display, fontname);	/* BUG: grey fonts */
72 		if(font == nil){
73 			fprint(2, "initdraw: can't open font %s: %r\n", fontname);
74 			goto Error;
75 		}
76 	}
77 	display->defaultfont = font;
78 
79 	display->white = allocimage(display, Rect(0,0,1,1), GREY1, 1, DWhite);
80 	display->black = allocimage(display, Rect(0,0,1,1), GREY1, 1, DBlack);
81 	if(display->white == nil || display->black == nil){
82 		fprint(2, "initdraw: can't allocate white and black");
83 		goto Error;
84 	}
85 	display->opaque = display->white;
86 	display->transparent = display->black;
87 
88 	_screen = allocscreen(display->image, display->white, 0);
89 	screen = _allocwindow(nil, _screen, display->image->r, Refnone, DWhite);
90 	display->screenimage = screen;
91 	draw(screen, screen->r, display->white, nil, ZP);
92 	flushimage(display, 1);
93 
94 	/*
95 	 * I don't see any reason to go away gracefully,
96 	 * and if some other proc exits holding the display
97 	 * lock, this atexit call never finishes.
98 	 *
99 	 * atexit(drawshutdown);
100 	 */
101 	return 1;
102 }
103 
104 /*
105  * Call with d unlocked.
106  * Note that disp->defaultfont and defaultsubfont are not freed here.
107  */
108 void
109 closedisplay(Display *disp)
110 {
111 	int fd;
112 	char buf[128];
113 
114 	if(disp == nil)
115 		return;
116 	if(disp == display)
117 		display = nil;
118 	if(disp->oldlabel[0]){
119 		snprint(buf, sizeof buf, "%s/label", disp->windir);
120 		fd = open(buf, OWRITE);
121 		if(fd >= 0){
122 			write(fd, disp->oldlabel, strlen(disp->oldlabel));
123 			close(fd);
124 		}
125 	}
126 
127 	free(disp->devdir);
128 	free(disp->windir);
129 	if(disp->white)
130 		freeimage(disp->white);
131 	if(disp->black)
132 		freeimage(disp->black);
133 	free(disp);
134 }
135 
136 void
137 lockdisplay(Display *disp)
138 {
139 	if(debuglockdisplay){
140 		/* avoid busy looping; it's rare we collide anyway */
141 		while(!canqlock(&disp->qlock)){
142 			fprint(1, "proc %d waiting for display lock...\n", getpid());
143 			sleep(1000);
144 		}
145 	}else
146 		qlock(&disp->qlock);
147 }
148 
149 void
150 unlockdisplay(Display *disp)
151 {
152 	qunlock(&disp->qlock);
153 }
154 
155 void
156 drawerror(Display *d, char *s)
157 {
158 	char err[ERRMAX];
159 
160 	if(d->error)
161 		d->error(d, s);
162 	else{
163 		errstr(err, sizeof err);
164 		fprint(2, "draw: %s: %s\n", s, err);
165 		exits(s);
166 	}
167 }
168 
169 static
170 int
171 doflush(Display *d)
172 {
173 	int n;
174 
175 	n = d->bufp-d->buf;
176 	if(n <= 0)
177 		return 1;
178 
179 	if(_drawmsgwrite(d, d->buf, n) != n){
180 		if(_drawdebug)
181 			fprint(2, "flushimage fail: d=%p: %r\n", d); /**/
182 		d->bufp = d->buf;	/* might as well; chance of continuing */
183 		return -1;
184 	}
185 	d->bufp = d->buf;
186 	return 1;
187 }
188 
189 int
190 flushimage(Display *d, int visible)
191 {
192 	if(visible){
193 		*d->bufp++ = 'v';	/* five bytes always reserved for this */
194 		if(d->_isnewdisplay){
195 			BPLONG(d->bufp, d->screenimage->id);
196 			d->bufp += 4;
197 		}
198 	}
199 	return doflush(d);
200 }
201 
202 uchar*
203 bufimage(Display *d, int n)
204 {
205 	uchar *p;
206 
207 	if(n<0 || d == nil || n>d->bufsize){
208 		abort();
209 		werrstr("bad count in bufimage");
210 		return 0;
211 	}
212 	if(d->bufp+n > d->buf+d->bufsize)
213 		if(doflush(d) < 0)
214 			return 0;
215 	p = d->bufp;
216 	d->bufp += n;
217 	return p;
218 }
219