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