aboutsummaryrefslogtreecommitdiff
path: root/src/libdraw/drawclient.c
blob: de20d3a3b4cde330ffdcf1a4fe5766af776f0d2f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
/* Copyright (c) 2006 Russ Cox */

#include <u.h>
#include <sys/select.h>
#include <libc.h>
#include <draw.h>
#include <mouse.h>
#include <cursor.h>
#include <drawfcall.h>
#include <mux.h>

extern Mouse _drawmouse;
int chattydrawclient = 0;

static int	drawgettag(Mux *mux, void *vmsg);
static void*	drawrecv(Mux *mux);
static int	drawnbrecv(Mux *mux, void**);
static int	drawsend(Mux *mux, void *vmsg);
static int	drawsettag(Mux *mux, void *vmsg, uint tag);
static int canreadfd(int);

int
_displayconnect(Display *d)
{
	int pid, p[2];
	
	fmtinstall('W', drawfcallfmt);
	fmtinstall('H', encodefmt);
	
	if(pipe(p) < 0)
		return -1;
	if((pid=fork()) < 0){
		close(p[0]);
		close(p[1]);
		return -1;
	}
	if(pid == 0){
		char *devdraw;
		close(p[0]);
		dup(p[1], 0);
		dup(p[1], 1);
		/* execl("strace", "strace", "-o", "drawsrv.out", "drawsrv", nil); */
		/*
		 * The argv0 has no meaning to devdraw.
		 * Pass it along only so that the various
		 * devdraws in psu -a can be distinguished.
		 * The NOLIBTHREADDAEMONIZE keeps devdraw from
		 * forking before threadmain. OS X hates it when
		 * guis fork.
		 *
		 * If client didn't use ARGBEGIN, argv0 == nil.
		 * Can't send nil through because OS X expects
		 * argv[0] to be non-nil.  Also, OS X apparently
		 * expects argv[0] to be a valid executable name,
		 * so "(argv0)" is not okay.  Use "devdraw"
		 * instead.
		 */
		putenv("NOLIBTHREADDAEMONIZE", "1");
		devdraw = getenv("DEVDRAW");
		if(devdraw == nil)
			devdraw = "devdraw";
		if(argv0 == nil)
			argv0 = devdraw;
		execl(devdraw, argv0, argv0, "(devdraw)", nil);
		sysfatal("exec devdraw: %r");
	}
	close(p[1]);
	d->srvfd = p[0];
	return 0;
}

int
_displaymux(Display *d)
{
	if((d->mux = mallocz(sizeof(*d->mux), 1)) == nil)
		return -1;

	d->mux->mintag = 1;
	d->mux->maxtag = 255;
	d->mux->send = drawsend;
	d->mux->recv = drawrecv;
	d->mux->nbrecv = drawnbrecv;
	d->mux->gettag = drawgettag;
	d->mux->settag = drawsettag;
	d->mux->aux = d;
	muxinit(d->mux);
	
	return 0;
}

static int
drawsend(Mux *mux, void *vmsg)
{
	int n;
	uchar *msg;
	Display *d;
	
	msg = vmsg;
	GET(msg, n);
	d = mux->aux;
	return write(d->srvfd, msg, n);
}

static int
_drawrecv(Mux *mux, int canblock, void **vp)
{
	int n;
	uchar buf[4], *p;
	Display *d;

	d = mux->aux;
	*vp = nil;
	if(!canblock && !canreadfd(d->srvfd))
		return 0;
	if((n=readn(d->srvfd, buf, 4)) != 4)
		return 1;
	GET(buf, n);
	p = malloc(n);
	if(p == nil){
		fprint(2, "out of memory allocating %d in drawrecv\n", n);
		return 1;
	}
	memmove(p, buf, 4);
	if(readn(d->srvfd, p+4, n-4) != n-4){
		free(p);
		return 1;
	}
	*vp = p;
	return 1;
}

static void*
drawrecv(Mux *mux)
{
	void *p;
	_drawrecv(mux, 1, &p);
	return p;
}

static int
drawnbrecv(Mux *mux, void **vp)
{
	return _drawrecv(mux, 0, vp);
}

static int
drawgettag(Mux *mux, void *vmsg)
{
	uchar *msg;
	USED(mux);
	
	msg = vmsg;
	return msg[4];
}

static int
drawsettag(Mux *mux, void *vmsg, uint tag)
{
	uchar *msg;
	USED(mux);
	
	msg = vmsg;
	msg[4] = tag;
	return 0;
}

static int
displayrpc(Display *d, Wsysmsg *tx, Wsysmsg *rx, void **freep)
{
	int n, nn;
	void *tpkt, *rpkt;
	
	n = sizeW2M(tx);
	tpkt = malloc(n);
	if(freep)
		*freep = nil;
	if(tpkt == nil)
		return -1;
	tx->tag = 0;
	if(chattydrawclient)
		fprint(2, "<- %W\n", tx);
	nn = convW2M(tx, tpkt, n);
	if(nn != n){
		free(tpkt);
		werrstr("drawclient: sizeW2M convW2M mismatch");
		fprint(2, "%r\n");
		return -1;
	}
	/*
	 * This is the only point where we might reschedule.
	 * Muxrpc might need to acquire d->mux->lk, which could
	 * be held by some other proc (e.g., the one reading from
	 * the keyboard via Trdkbd messages).  If we need to wait
	 * for the lock, don't let other threads from this proc
	 * run.  This keeps up the appearance that writes to /dev/draw
	 * don't cause rescheduling.  If you *do* allow rescheduling
	 * here, then flushimage(display, 1) happening in two different
	 * threads in the same proc can cause a buffer of commands
	 * to be written out twice, leading to interesting results
	 * on the screen.
	 *
	 * Threadpin and threadunpin were added to the thread library
	 * to solve exactly this problem.  Be careful!  They are dangerous.
	 *
	 * _pin and _unpin are aliases for threadpin and threadunpin
	 * in a threaded program and are no-ops in unthreaded programs.
	 */
	_pin();
	rpkt = muxrpc(d->mux, tpkt);
	_unpin();
	free(tpkt);
	if(rpkt == nil){
		werrstr("muxrpc: %r");
		return -1;
	}
	GET((uchar*)rpkt, n);
	nn = convM2W(rpkt, n, rx);
	if(nn != n){
		free(rpkt);
		werrstr("drawclient: convM2W packet size mismatch %d %d %.*H", n, nn, n, rpkt);
		fprint(2, "%r\n");
		return -1;
	}
	if(chattydrawclient)
		fprint(2, "-> %W\n", rx);
	if(rx->type == Rerror){
		werrstr("%s", rx->error);
		free(rpkt);
		return -1;
	}
	if(rx->type != tx->type+1){
		werrstr("packet type mismatch -- tx %d rx %d",
			tx->type, rx->type);
		free(rpkt);
		return -1;
	}
	if(freep)
		*freep = rpkt;
	else
		free(rpkt);
	return 0;
}

int
_displayinit(Display *d, char *label, char *winsize)
{
	Wsysmsg tx, rx;

	tx.type = Tinit;
	tx.label = label;
	tx.winsize = winsize;
	return displayrpc(d, &tx, &rx, nil);
}

int
_displayrdmouse(Display *d, Mouse *m, int *resized)
{
	Wsysmsg tx, rx;

	tx.type = Trdmouse;
	if(displayrpc(d, &tx, &rx, nil) < 0)
		return -1;
	_drawmouse = rx.mouse;
	*m = rx.mouse;
	*resized = rx.resized;
	return 0;
}

int
_displayrdkbd(Display *d, Rune *r)
{
	Wsysmsg tx, rx;

	tx.type = Trdkbd;
	if(displayrpc(d, &tx, &rx, nil) < 0)
		return -1;
	*r = rx.rune;
	return 0;
}

int
_displaymoveto(Display *d, Point p)
{
	Wsysmsg tx, rx;

	tx.type = Tmoveto;
	tx.mouse.xy = p;
	if(displayrpc(d, &tx, &rx, nil) < 0)
		return -1;
	_drawmouse.xy = p;
	return flushimage(d, 1);
}

int
_displaycursor(Display *d, Cursor *c, Cursor2 *c2)
{
	Wsysmsg tx, rx;
	
	tx.type = Tcursor;
	if(c == nil){
		memset(&tx.cursor, 0, sizeof tx.cursor);
		memset(&tx.cursor2, 0, sizeof tx.cursor2);
		tx.arrowcursor = 1;
	}else{
		tx.arrowcursor = 0;
		tx.cursor = *c;
		if(c2 != nil)
			tx.cursor2 = *c2;
		else
			scalecursor(&tx.cursor2, c);
	}
	return displayrpc(d, &tx, &rx, nil);
}

int
_displaybouncemouse(Display *d, Mouse *m)
{
	Wsysmsg tx, rx;
	
	tx.type = Tbouncemouse;
	tx.mouse = *m;
	return displayrpc(d, &tx, &rx, nil);
}

int
_displaylabel(Display *d, char *label)
{
	Wsysmsg tx, rx;
	
	tx.type = Tlabel;
	tx.label = label;
	return displayrpc(d, &tx, &rx, nil);
}

char*
_displayrdsnarf(Display *d)
{
	void *p;
	char *s;
	Wsysmsg tx, rx;
	
	tx.type = Trdsnarf;
	if(displayrpc(d, &tx, &rx, &p) < 0)
		return nil;
	s = strdup(rx.snarf);
	free(p);
	return s;
}

int
_displaywrsnarf(Display *d, char *snarf)
{
	Wsysmsg tx, rx;
	
	tx.type = Twrsnarf;
	tx.snarf = snarf;
	return displayrpc(d, &tx, &rx, nil);
}

int
_displayrddraw(Display *d, void *v, int n)
{
	void *p;
	Wsysmsg tx, rx;
	
	tx.type = Trddraw;
	tx.count = n;
	if(displayrpc(d, &tx, &rx, &p) < 0)
		return -1;
	memmove(v, rx.data, rx.count);
	free(p);
	return rx.count;
}

int
_displaywrdraw(Display *d, void *v, int n)
{
	Wsysmsg tx, rx;
	
	tx.type = Twrdraw;
	tx.count = n;
	tx.data = v;
	if(displayrpc(d, &tx, &rx, nil) < 0)
		return -1;
	return rx.count;
}

int
_displaytop(Display *d)
{
	Wsysmsg tx, rx;

	tx.type = Ttop;
	return displayrpc(d, &tx, &rx, nil);
}

int
_displayresize(Display *d, Rectangle r)
{
	Wsysmsg tx, rx;
	
	tx.type = Tresize;
	tx.rect = r;
	return displayrpc(d, &tx, &rx, nil);
}

static int
canreadfd(int fd)
{
	fd_set rs, ws, xs;
	struct timeval tv;
	
	FD_ZERO(&rs);
	FD_ZERO(&ws);
	FD_ZERO(&xs);
	FD_SET(fd, &rs);
	FD_SET(fd, &xs);
	tv.tv_sec = 0;
	tv.tv_usec = 0;
	if(select(fd+1, &rs, &ws, &xs, &tv) < 0)
		return 0;
	if(FD_ISSET(fd, &rs) || FD_ISSET(fd, &xs))
		return 1;
	return 0;
}