1 /*
2  * Copyright (c) 2022, 2023 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "config.h"
18 
19 #include <limits.h>
20 
21 #include <assert.h>
22 #include <errno.h>
23 #include <poll.h>
24 #include <signal.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <stdint.h>
28 #include <string.h>
29 #include <syslog.h>
30 #include <unistd.h>
31 
32 #include "amused.h"
33 #include "log.h"
34 #include "xmalloc.h"
35 
36 struct pollfd		*player_pfds;
37 int			 player_nfds;
38 static struct imsgbuf	*imsgbuf;
39 
40 static int nextfd = -1;
41 static int64_t samples;
42 static int64_t duration;
43 static unsigned int current_rate;
44 
45 volatile sig_atomic_t halted;
46 
47 static void
48 player_signal_handler(int signo)
49 {
50 	halted = 1;
51 }
52 
53 int
54 player_setup(unsigned int bits, unsigned int rate, unsigned int channels)
55 {
56 	log_debug("%s: bits=%u, rate=%u, channels=%u", __func__,
57 	    bits, rate, channels);
58 
59 	current_rate = rate;
60 	return audio_setup(bits, rate, channels, player_pfds + 1, player_nfds);
61 }
62 
63 void
64 player_setduration(int64_t d)
65 {
66 	int64_t seconds;
67 
68 	duration = d;
69 	seconds = duration / current_rate;
70 	imsg_compose(imsgbuf, IMSG_LEN, 0, 0, -1, &seconds, sizeof(seconds));
71 	imsg_flush(imsgbuf);
72 }
73 
74 static void
75 player_onmove(void *arg, int delta)
76 {
77 	static int64_t reported;
78 	int64_t sec;
79 
80 	samples += delta;
81 	if (llabs(samples - reported) >= current_rate) {
82 		reported = samples;
83 		sec = samples / current_rate;
84 
85 		imsg_compose(imsgbuf, IMSG_POS, 0, 0, -1, &sec, sizeof(sec));
86 		imsg_flush(imsgbuf);
87 	}
88 }
89 
90 void
91 player_setpos(int64_t pos)
92 {
93 	samples = pos;
94 	player_onmove(NULL, 0);
95 }
96 
97 /* process only one message */
98 static int
99 player_dispatch(int64_t *s, int wait)
100 {
101 	struct player_seek seek;
102 	struct pollfd	pfd;
103 	struct imsg	imsg;
104 	ssize_t		n;
105 	int		ret;
106 
107 	if (halted != 0)
108 		return IMSG_STOP;
109 
110 again:
111 	if ((n = imsg_get(imsgbuf, &imsg)) == -1)
112 		fatal("imsg_get");
113 	if (n == 0) {
114 		if (!wait)
115 			return -1;
116 
117 		pfd.fd = imsgbuf->fd;
118 		pfd.events = POLLIN;
119 		if (poll(&pfd, 1, INFTIM) == -1)
120 			fatal("poll");
121 		if ((n = imsg_read(imsgbuf)) == -1 && errno != EAGAIN)
122 			fatal("imsg_read");
123 		if (n == 0)
124 			fatalx("pipe closed");
125 		goto again;
126 	}
127 
128 	ret = imsg_get_type(&imsg);
129 	switch (ret) {
130 	case IMSG_PLAY:
131 		if (nextfd != -1)
132 			fatalx("track already enqueued");
133 		if ((nextfd = imsg_get_fd(&imsg)) == -1)
134 			fatalx("%s: got invalid file descriptor", __func__);
135 		log_debug("song enqueued");
136 		ret = IMSG_STOP;
137 		break;
138 	case IMSG_RESUME:
139 	case IMSG_PAUSE:
140 	case IMSG_STOP:
141 		break;
142 	case IMSG_CTL_SEEK:
143 		if (s == NULL)
144 			break;
145 		if (imsg_get_data(&imsg, &seek, sizeof(seek)) == -1)
146 			fatalx("wrong size for seek ctl");
147 		if (seek.percent)
148 			*s = (double)seek.offset * (double)duration / 100.0;
149 		else
150 			*s = seek.offset * current_rate;
151 		if (seek.relative)
152 			*s += samples;
153 		if (*s < 0)
154 			*s = 0;
155 		break;
156 	default:
157 		fatalx("unknown imsg %d", ret);
158 	}
159 
160 	imsg_free(&imsg);
161 	return ret;
162 }
163 
164 static void
165 player_senderr(const char *errstr)
166 {
167 	size_t len = 0;
168 
169 	if (errstr != NULL)
170 		len = strlen(errstr) + 1;
171 
172 	imsg_compose(imsgbuf, IMSG_ERR, 0, 0, -1, errstr, len);
173 	imsg_flush(imsgbuf);
174 }
175 
176 static void
177 player_sendeof(void)
178 {
179 	imsg_compose(imsgbuf, IMSG_EOF, 0, 0, -1, NULL, 0);
180 	imsg_flush(imsgbuf);
181 }
182 
183 static int
184 player_playnext(const char **errstr)
185 {
186 	static char buf[512];
187 	ssize_t r;
188 	int fd = nextfd;
189 
190 	assert(nextfd != -1);
191 	nextfd = -1;
192 
193 	/* reset samples and set position to zero */
194 	samples = 0;
195 	imsg_compose(imsgbuf, IMSG_POS, 0, 0, -1, &samples, sizeof(samples));
196 	imsg_flush(imsgbuf);
197 
198 	r = read(fd, buf, sizeof(buf));
199 
200 	/* 8 byte is the larger magic number */
201 	if (r < 8) {
202 		*errstr = "read failed";
203 		goto err;
204 	}
205 
206 	if (lseek(fd, 0, SEEK_SET) == -1) {
207 		*errstr = "lseek failed";
208 		goto err;
209 	}
210 
211 	if (memcmp(buf, "fLaC", 4) == 0)
212 		return play_flac(fd, errstr);
213 	if (memcmp(buf, "ID3", 3) == 0 ||
214 	    memcmp(buf, "\xFF\xFB", 2) == 0)
215 		return play_mp3(fd, errstr);
216 	if (memmem(buf, r, "OpusHead", 8) != NULL)
217 		return play_opus(fd, errstr);
218 	if (memmem(buf, r, "OggS", 4) != NULL)
219 		return play_oggvorbis(fd, errstr);
220 
221 	*errstr = "unknown file type";
222 err:
223 	close(fd);
224 	return -1;
225 }
226 
227 static int
228 player_pause(int64_t *s)
229 {
230 	int r;
231 
232 	r = player_dispatch(s, 1);
233 	return r == IMSG_RESUME || r == IMSG_CTL_SEEK;
234 }
235 
236 static int
237 player_shouldstop(int64_t *s, int wait)
238 {
239 	switch (player_dispatch(s, wait)) {
240 	case IMSG_PAUSE:
241 		if (player_pause(s))
242 			break;
243 		/* fallthrough */
244 	case IMSG_STOP:
245 		return 1;
246 	}
247 
248 	return 0;
249 }
250 
251 int
252 play(const void *buf, size_t len, int64_t *s)
253 {
254 	size_t w;
255 	int revents, r, wait;
256 
257 	*s = -1;
258 	while (len != 0) {
259 		audio_pollfd(player_pfds + 1, player_nfds, POLLOUT);
260 		r = poll(player_pfds, player_nfds + 1, INFTIM);
261 		if (r == -1)
262 			fatal("poll");
263 
264 		wait = player_pfds[0].revents & (POLLHUP|POLLIN);
265 		if (player_shouldstop(s, wait)) {
266 			audio_flush();
267 			return 0;
268 		}
269 
270 		revents = audio_revents(player_pfds + 1, player_nfds);
271 		if (revents & POLLHUP) {
272 			if (errno == EAGAIN)
273 				continue;
274 			fatal("audio hang-up");
275 		}
276 		if (revents & POLLOUT) {
277 			w = audio_write(buf, len);
278 			len -= w;
279 			buf += w;
280 		}
281 	}
282 
283 	return 1;
284 }
285 
286 int
287 player(int debug, int verbose)
288 {
289 	int r;
290 
291 	log_init(debug, LOG_DAEMON);
292 	log_setverbose(verbose);
293 
294 	setproctitle("player");
295 	log_procinit("player");
296 
297 #if 0
298 	{
299 		static int attached;
300 
301 		while (!attached)
302 			sleep(1);
303 	}
304 #endif
305 
306 	if (audio_open(player_onmove) == -1)
307 		fatal("audio_open");
308 
309 	if ((player_nfds = audio_nfds()) <= 0)
310 		fatal("audio_nfds: invalid number of file descriptors: %d",
311 		    player_nfds);
312 
313 	/* allocate one extra for imsg */
314 	player_pfds = calloc(player_nfds + 1, sizeof(*player_pfds));
315 	if (player_pfds == NULL)
316 		fatal("calloc");
317 
318 	player_pfds[0].events = POLLIN;
319 	player_pfds[0].fd = 3;
320 
321 	imsgbuf = xmalloc(sizeof(*imsgbuf));
322 	imsg_init(imsgbuf, 3);
323 
324 	signal(SIGINT, player_signal_handler);
325 	signal(SIGTERM, player_signal_handler);
326 
327 	signal(SIGHUP, SIG_IGN);
328 	signal(SIGPIPE, SIG_IGN);
329 
330 	if (pledge("stdio recvfd audio", NULL) == -1)
331 		fatal("pledge");
332 
333 	while (!halted) {
334 		const char *errstr = NULL;
335 
336 		while (nextfd == -1)
337 			player_dispatch(NULL, 1);
338 
339 		r = player_playnext(&errstr);
340 		if (r == -1)
341 			player_senderr(errstr);
342 		if (r == 0)
343 			player_sendeof();
344 	}
345 
346 	return 0;
347 }