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 static void
16 drawshutdown(void)
17 {
18 	Display *d;
19 
20 	d = display;
21 	if(d){
22 		display = nil;
23 		closedisplay(d);
24 	}
25 }
26 
27 int
28 initdraw(void (*error)(Display*, char*), char *fontname, char *label)
29 {
30 	Subfont *df;
31 	char buf[128];
32 
33 	display = _initdisplay(error, label); /* sets screen too */
34 	if(display == nil)
35 		return -1;
36 
37 	lockdisplay(display);
38 	display->screenimage = display->image;
39 
40 	/*
41 	 * Set up default font
42 	 */
43 	df = getdefont(display);
44 	display->defaultsubfont = df;
45 	if(df == nil){
46 		fprint(2, "imageinit: can't open default subfont: %r\n");
47     Error:
48 		closedisplay(display);
49 		display = nil;
50 		return -1;
51 	}
52 	if(fontname == nil)
53 		fontname = getenv("font");	/* leak */
54 
55 	/*
56 	 * Build fonts with caches==depth of screen, for speed.
57 	 * If conversion were faster, we'd use 0 and save memory.
58 	 */
59 	if(fontname == nil){
60 		snprint(buf, sizeof buf, "%d %d\n0 %d\t%s\n", df->height, df->ascent,
61 			df->n-1, deffontname);
62 //BUG: Need something better for this	installsubfont("*default*", df);
63 		font = buildfont(display, buf, deffontname);
64 		if(font == nil){
65 			fprint(2, "initdraw: can't open default font: %r\n");
66 			goto Error;
67 		}
68 	}else{
69 		font = openfont(display, fontname);	/* BUG: grey fonts */
70 		if(font == nil){
71 			fprint(2, "initdraw: can't open font %s: %r\n", fontname);
72 			goto Error;
73 		}
74 	}
75 	display->defaultfont = font;
76 
77 	display->white = allocimage(display, Rect(0,0,1,1), GREY1, 1, DWhite);
78 	display->black = allocimage(display, Rect(0,0,1,1), GREY1, 1, DBlack);
79 	if(display->white == nil || display->black == nil){
80 		fprint(2, "initdraw: can't allocate white and black");
81 		goto Error;
82 	}
83 	display->opaque = display->white;
84 	display->transparent = display->black;
85 
86 	_screen = allocscreen(display->image, display->white, 0);
87 	screen = _allocwindow(nil, _screen, display->image->r, Refnone, DWhite);
88 	display->screenimage = screen;
89 	draw(screen, screen->r, display->black, nil, ZP);
90 	flushimage(display, 1);
91 
92 	atexit(drawshutdown);
93 	return 1;
94 }
95 
96 /*
97  * Call with d unlocked.
98  * Note that disp->defaultfont and defaultsubfont are not freed here.
99  */
100 void
101 closedisplay(Display *disp)
102 {
103 	int fd;
104 	char buf[128];
105 
106 	if(disp == nil)
107 		return;
108 	if(disp == display)
109 		display = nil;
110 	if(disp->oldlabel[0]){
111 		snprint(buf, sizeof buf, "%s/label", disp->windir);
112 		fd = open(buf, OWRITE);
113 		if(fd >= 0){
114 			write(fd, disp->oldlabel, strlen(disp->oldlabel));
115 			close(fd);
116 		}
117 	}
118 
119 	free(disp->devdir);
120 	free(disp->windir);
121 	freeimage(disp->white);
122 	freeimage(disp->black);
123 	free(disp);
124 }
125 
126 void
127 lockdisplay(Display *disp)
128 {
129 	if(debuglockdisplay){
130 		/* avoid busy looping; it's rare we collide anyway */
131 		while(!canqlock(&disp->qlock)){
132 			fprint(1, "proc %d waiting for display lock...\n", getpid());
133 			sleep(1000);
134 		}
135 	}else
136 		qlock(&disp->qlock);
137 }
138 
139 void
140 unlockdisplay(Display *disp)
141 {
142 	qunlock(&disp->qlock);
143 }
144 
145 void
146 drawerror(Display *d, char *s)
147 {
148 	char err[ERRMAX];
149 
150 	if(d->error)
151 		d->error(d, s);
152 	else{
153 		errstr(err, sizeof err);
154 		fprint(2, "draw: %s: %s\n", s, err);
155 		exits(s);
156 	}
157 }
158 
159 static
160 int
161 doflush(Display *d)
162 {
163 	int n;
164 
165 	n = d->bufp-d->buf;
166 	if(n <= 0)
167 		return 1;
168 
169 	if(_drawmsgwrite(d, d->buf, n) != n){
170 		if(_drawdebug)
171 			fprint(2, "flushimage fail: d=%p: %r\n", d); /**/
172 		d->bufp = d->buf;	/* might as well; chance of continuing */
173 		return -1;
174 	}
175 	d->bufp = d->buf;
176 	return 1;
177 }
178 
179 int
180 flushimage(Display *d, int visible)
181 {
182 	if(visible){
183 		*d->bufp++ = 'v';	/* five bytes always reserved for this */
184 		if(d->_isnewdisplay){
185 			BPLONG(d->bufp, d->screenimage->id);
186 			d->bufp += 4;
187 		}
188 	}
189 	return doflush(d);
190 }
191 
192 uchar*
193 bufimage(Display *d, int n)
194 {
195 	uchar *p;
196 
197 	if(n<0 || n>d->bufsize){
198 abort();
199 		werrstr("bad count in bufimage");
200 		return 0;
201 	}
202 	if(d->bufp+n > d->buf+d->bufsize)
203 		if(doflush(d) < 0)
204 			return 0;
205 	p = d->bufp;
206 	d->bufp += n;
207 	return p;
208 }
209