Merge branch 'maint'
[paraslash.git] / audiod_command.c
1 /* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
2
3 /** \file audiod_command.c Commands for para_audiod. */
4
5 #include <netinet/in.h>
6 #include <sys/socket.h>
7 #include <regex.h>
8 #include <sys/types.h>
9 #include <arpa/inet.h>
10 #include <sys/un.h>
11 #include <netdb.h>
12 #include <lopsub.h>
13
14 #include "audiod.lsg.h"
15 #include "para.h"
16 #include "lsu.h"
17 #include "audiod_cmd.lsg.h"
18 #include "list.h"
19 #include "sched.h"
20 #include "buffer_tree.h"
21 #include "filter.h"
22 #include "grab_client.h"
23 #include "error.h"
24 #include "audiod.h"
25 #include "net.h"
26 #include "daemon.h"
27 #include "string.h"
28 #include "write.h"
29 #include "fd.h"
30 #include "version.h"
31
32 extern struct sched sched;
33 extern char *stat_item_values[NUM_STAT_ITEMS];
34
35 /** The maximal number of simultaneous connections. */
36 #define MAX_STAT_CLIENTS 50
37
38 /** Pointer to a command handler function. */
39 typedef int (*audiod_cmd_handler_t)(int, struct lls_parse_result *);
40
41 /** The lopsub user_data pointer. Only the command handler at the moment. */
42 struct audiod_command_info {
43 audiod_cmd_handler_t handler; /**< Implementation of the command. */
44 };
45
46 /** Define the user_data pointer as expected by lopsub. */
47 #define EXPORT_AUDIOD_CMD_HANDLER(_cmd) \
48 /** Implementation of _cmd. */ \
49 const struct audiod_command_info lsg_audiod_cmd_com_ ## _cmd ## _user_data = { \
50 .handler = com_ ## _cmd \
51 };
52
53 /** Flags used for the stat command of para_audiod. */
54 enum stat_client_flags {
55 /** Enable parser-friendly output. */
56 SCF_PARSER_FRIENDLY = 1,
57 };
58
59 /**
60 * Describes a status client of para_audiod.
61 *
62 * There's one such structure per audiod client that sent the 'stat' command.
63 *
64 * A status client is identified by its file descriptor. para_audiod
65 * keeps a list of connected status clients.
66 */
67 struct stat_client {
68 /** The stat client's file descriptor. */
69 int fd;
70 /** Bitmask of those status items the client is interested in. */
71 uint64_t item_mask;
72 /** See \ref stat_client flags. */
73 unsigned flags;
74 /** Its entry in the list of stat clients. */
75 struct list_head node;
76 };
77
78 static INITIALIZED_LIST_HEAD(client_list);
79 static int num_clients;
80
81 /** The list of all status items used by para_{server,audiod,gui}. */
82 const char *status_item_list[] = {STATUS_ITEMS};
83
84 static void dump_stat_client_list(void)
85 {
86 struct stat_client *sc;
87
88 list_for_each_entry(sc, &client_list, node)
89 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
90 }
91 /**
92 * Add a status client to the list.
93 *
94 * \param fd The file descriptor of the client.
95 * \param mask Bitfield of status items for this client.
96 * \param parser_friendly Enable parser-friendly output mode.
97 *
98 * Only those status items having the bit set in \a mask will be
99 * sent to the client.
100 *
101 * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
102 * the number of connected clients exceeds #MAX_STAT_CLIENTS.
103 */
104 static int stat_client_add(int fd, uint64_t mask, int parser_friendly)
105 {
106 struct stat_client *new_client;
107 int ret;
108
109 if (num_clients >= MAX_STAT_CLIENTS) {
110 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
111 MAX_STAT_CLIENTS);
112 return -E_TOO_MANY_CLIENTS;
113 }
114 ret = dup(fd);
115 if (ret < 0)
116 return -ERRNO_TO_PARA_ERROR(errno);
117 new_client = zalloc(sizeof(*new_client));
118 new_client->fd = ret;
119 PARA_INFO_LOG("adding client on fd %d\n", new_client->fd);
120 new_client->item_mask = mask;
121 if (parser_friendly)
122 new_client->flags = SCF_PARSER_FRIENDLY;
123 para_list_add(&new_client->node, &client_list);
124 dump_stat_client_list();
125 num_clients++;
126 return 1;
127 }
128
129 static void close_stat_client(struct stat_client *sc)
130 {
131 PARA_INFO_LOG("closing client fd %d\n", sc->fd);
132 close(sc->fd);
133 list_del(&sc->node);
134 free(sc);
135 num_clients--;
136 }
137
138 /**
139 * Empty the status clients list.
140 *
141 * This iterates over the list of connected status clients, closes each client
142 * file descriptor and frees the resources.
143 */
144 void close_stat_clients(void)
145 {
146 struct stat_client *sc, *tmp;
147
148 list_for_each_entry_safe(sc, tmp, &client_list, node)
149 close_stat_client(sc);
150 assert(num_clients == 0);
151 }
152
153 /**
154 * Write a message to all connected status clients.
155 *
156 * \param item_num The number of the status item of \a msg.
157 *
158 * On write errors, remove the status client from the client list and close its
159 * file descriptor.
160 */
161 void stat_client_write_item(int item_num)
162 {
163 struct stat_client *sc, *tmp;
164 struct para_buffer pb = {.flags = 0};
165 struct para_buffer pfpb = {.flags = PBF_SIZE_PREFIX};
166 const uint64_t one = 1;
167 char *msg = stat_item_values[item_num];
168 struct para_buffer *b;
169
170 list_for_each_entry_safe(sc, tmp, &client_list, node) {
171 int ret;
172
173 if (!((one << item_num) & sc->item_mask))
174 continue;
175 b = (sc->flags & SCF_PARSER_FRIENDLY)? &pfpb : &pb;
176 if (!b->buf)
177 WRITE_STATUS_ITEM(b, item_num, "%s\n", msg? msg : "");
178 ret = write(sc->fd, b->buf, b->offset);
179 if (ret == b->offset)
180 continue;
181 /* write error or short write */
182 close_stat_client(sc);
183 dump_stat_client_list();
184 }
185 free(pb.buf);
186 free(pfpb.buf);
187 }
188
189 /**
190 * Check if string is a known status item.
191 *
192 * \param item Buffer containing the text to check.
193 *
194 * \return If \a item is a valid status item, the number of that status item is
195 * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
196 */
197 static int stat_item_valid(const char *item)
198 {
199 int i;
200 if (!item || !*item) {
201 PARA_ERROR_LOG("%s\n", "no item");
202 return -E_UNKNOWN_STAT_ITEM;
203 }
204 FOR_EACH_STATUS_ITEM(i)
205 if (!strcmp(status_item_list[i], item))
206 return i;
207 PARA_ERROR_LOG("invalid stat item: %s\n", item);
208 return -E_UNKNOWN_STAT_ITEM;
209 }
210
211 static int client_write(int fd, const char *buf)
212 {
213 size_t len;
214
215 if (!buf)
216 return 0;
217 len = strlen(buf);
218 return write(fd, buf, len) != len? -E_CLIENT_WRITE: 1;
219 }
220
221 __malloc static char *audiod_status_string(void)
222 {
223 const char *status = (audiod_status == AUDIOD_ON)?
224 "on" : (audiod_status == AUDIOD_OFF)? "off": "sb";
225 return para_strdup(status);
226 }
227
228 static int com_help(int fd, struct lls_parse_result *lpr)
229 {
230 char *buf;
231 int ret;
232 const struct lls_opt_result *r =
233 lls_opt_result(LSG_AUDIOD_CMD_HELP_OPT_LONG, lpr);
234 bool long_help = lls_opt_given(r);
235
236 lsu_com_help(long_help, lpr, audiod_cmd_suite, NULL, &buf, NULL);
237 ret = client_write(fd, buf);
238 free(buf);
239 return ret < 0? ret : 0;
240 }
241 EXPORT_AUDIOD_CMD_HANDLER(help)
242
243 static int com_ll(int fd, struct lls_parse_result *lpr)
244 {
245 unsigned ll;
246 char *errctx;
247 const char *sev[] = {SEVERITIES};
248 const char *arg;
249 int ret = lls(lls_check_arg_count(lpr, 0, 1, &errctx));
250
251 if (ret < 0) {
252 char *tmp = make_message("%s\n", errctx);
253 free(errctx);
254 client_write(fd, tmp);
255 free(tmp);
256 return ret;
257 }
258 if (lls_num_inputs(lpr) == 0) {
259 char *msg;
260 ll = daemon_get_loglevel();
261 msg = make_message("%s\n", sev[ll]);
262 ret = client_write(fd, msg);
263 free(msg);
264 return ret;
265 }
266 arg = lls_input(0, lpr);
267 for (ll = 0; ll < NUM_LOGLEVELS; ll++) {
268 if (!strcmp(arg, sev[ll]))
269 break;
270 }
271 if (ll >= NUM_LOGLEVELS)
272 return -ERRNO_TO_PARA_ERROR(EINVAL);
273 PARA_INFO_LOG("new log level: %s\n", sev[ll]);
274 daemon_set_loglevel(ll);
275 return 1;
276 }
277 EXPORT_AUDIOD_CMD_HANDLER(ll)
278
279 static int com_tasks(int fd, __a_unused struct lls_parse_result *lpr)
280 {
281 int ret;
282 char *tl = get_task_list(&sched);
283
284 if (!tl) /* no tasks registered yet */
285 return 0;
286 ret = client_write(fd, tl);
287 free(tl);
288 return ret;
289 }
290 EXPORT_AUDIOD_CMD_HANDLER(tasks)
291
292 static int com_stat(int fd, struct lls_parse_result *lpr)
293 {
294 int i, ret, parser_friendly = 0;
295 uint64_t mask = 0;
296 const uint64_t one = 1;
297 struct para_buffer b = {.flags = 0};
298 const struct lls_opt_result *r;
299 unsigned num_inputs;
300
301 ret = mark_fd_nonblocking(fd);
302 if (ret < 0)
303 return ret;
304 r = lls_opt_result(LSG_AUDIOD_CMD_STAT_OPT_PARSER_FRIENDLY, lpr);
305 if (lls_opt_given(r) > 0) {
306 parser_friendly = 1;
307 b.flags = PBF_SIZE_PREFIX;
308 }
309 num_inputs = lls_num_inputs(lpr);
310 if (num_inputs == 0)
311 mask--; /* set all bits */
312 for (i = 0; i < num_inputs; i++) {
313 ret = stat_item_valid(lls_input(i, lpr));
314 if (ret < 0)
315 return ret;
316 mask |= (one << ret);
317 }
318 PARA_INFO_LOG("mask: 0x%llx\n", (long long unsigned)mask);
319 FOR_EACH_STATUS_ITEM(i) {
320 char *item = stat_item_values[i];
321 if (!((one << i) & mask))
322 continue;
323 WRITE_STATUS_ITEM(&b, i, "%s\n", item? item : "");
324 }
325 ret = client_write(fd, b.buf);
326 if (ret >= 0)
327 ret = stat_client_add(fd, mask, parser_friendly);
328 free(b.buf);
329 return ret < 0? ret : 0;
330 }
331 EXPORT_AUDIOD_CMD_HANDLER(stat)
332
333 static int com_grab(int fd, struct lls_parse_result *lpr)
334 {
335 int ret = grab_client_new(fd, lpr, &sched);
336 return ret < 0? ret : 0;
337 }
338 EXPORT_AUDIOD_CMD_HANDLER(grab)
339
340 static int com_term(__a_unused int fd, __a_unused struct lls_parse_result *lpr)
341 {
342 return -E_AUDIOD_TERM;
343 }
344 EXPORT_AUDIOD_CMD_HANDLER(term)
345
346 static int com_on(__a_unused int fd, __a_unused struct lls_parse_result *lpr)
347 {
348 audiod_status = AUDIOD_ON;
349 return 1;
350 }
351 EXPORT_AUDIOD_CMD_HANDLER(on)
352
353 static int com_off(__a_unused int fd, __a_unused struct lls_parse_result *lpr)
354 {
355 audiod_status = AUDIOD_OFF;
356 return 1;
357 }
358 EXPORT_AUDIOD_CMD_HANDLER(off)
359
360 static int com_sb(__a_unused int fd, __a_unused struct lls_parse_result *lpr)
361 {
362 audiod_status = AUDIOD_STANDBY;
363 return 1;
364 }
365 EXPORT_AUDIOD_CMD_HANDLER(sb)
366
367 static int com_cycle(__a_unused int fd, __a_unused struct lls_parse_result *lpr)
368 {
369 switch (audiod_status) {
370 case AUDIOD_ON: audiod_status = AUDIOD_STANDBY; break;
371 case AUDIOD_OFF: audiod_status = AUDIOD_ON; break;
372 case AUDIOD_STANDBY: audiod_status = AUDIOD_OFF; break;
373 }
374 return 1;
375 }
376 EXPORT_AUDIOD_CMD_HANDLER(cycle)
377
378 static int com_version(int fd, struct lls_parse_result *lpr)
379 {
380 int ret;
381 char *msg;
382 const struct lls_opt_result *r_v;
383
384 r_v = lls_opt_result(LSG_AUDIOD_CMD_VERSION_OPT_VERBOSE, lpr);
385 if (lls_opt_given(r_v))
386 msg = make_message("%s", version_text("audiod"));
387 else
388 msg = make_message("%s\n", version_single_line("audiod"));
389 ret = client_write(fd, msg);
390 free(msg);
391 return ret < 0? ret : 0;
392 }
393 EXPORT_AUDIOD_CMD_HANDLER(version)
394
395 /**
396 * Handle arriving connections on the local socket.
397 *
398 * \param accept_fd The fd to accept connections on.
399 *
400 * This is called in each iteration of the main loop of the scheduler. If there
401 * is an incoming connection, the function reads the command sent by the peer,
402 * checks the connecting user's permissions by using unix socket credentials
403 * (if supported by the OS) and calls the corresponding command handler if
404 * permissions are OK.
405 *
406 * \return Positive on success, negative on errors, zero if there was no
407 * connection to accept.
408 *
409 * \sa \ref para_accept(), \ref recv_cred_buffer().
410 */
411 int dispatch_local_connection(int accept_fd)
412 {
413 int argc, ret, clifd;
414 char buf[MAXLINE], **argv = NULL;
415 struct sockaddr_un unix_addr;
416 uid_t uid;
417 const struct lls_command *cmd;
418 struct lls_parse_result *lpr;
419 char *errctx = NULL;
420 const struct audiod_command_info *aci;
421
422 ret = para_accept(accept_fd, &unix_addr, sizeof(struct sockaddr_un), &clifd);
423 if (ret <= 0)
424 return ret;
425 ret = recv_cred_buffer(clifd, buf, sizeof(buf) - 1);
426 if (ret < 0)
427 goto out;
428 uid = ret;
429 PARA_INFO_LOG("connection from UID %d, buf: %s\n", ret, buf);
430 ret = -E_UCRED_PERM;
431 if (!uid_is_whitelisted(uid))
432 goto out;
433 ret = create_argv(buf, "\n", &argv);
434 if (ret <= 0)
435 goto out;
436 argc = ret;
437 ret = lls(lls_lookup_subcmd(argv[0], audiod_cmd_suite, &errctx));
438 if (ret < 0)
439 goto out;
440 cmd = lls_cmd(ret, audiod_cmd_suite);
441 ret = lls(lls_parse(argc, argv, cmd, &lpr, &errctx));
442 if (ret < 0)
443 goto out;
444 aci = lls_user_data(cmd);
445 ret = aci->handler(clifd, lpr);
446 lls_free_parse_result(lpr, cmd);
447 out:
448 free_argv(argv);
449 if (ret < 0 && ret != -E_CLIENT_WRITE) {
450 char *tmp;
451 if (errctx) {
452 tmp = make_message("%s\n", errctx);
453 free(errctx);
454 client_write(clifd, tmp);
455 free(tmp);
456 }
457 tmp = make_message("%s\n", para_strerror(-ret));
458 client_write(clifd, tmp);
459 free(tmp);
460 }
461 close(clifd);
462 return ret;
463 }
464
465 /**
466 * Send the current audiod status to all connected stat clients.
467 *
468 * \param force Whether to write unchanged items.
469 */
470 void audiod_status_dump(bool force)
471 {
472 char *old, *new;
473
474 old = stat_item_values[SI_play_time];
475 new = get_time_string();
476 if (new) {
477 if (force || !old || strcmp(old, new)) {
478 free(old);
479 stat_item_values[SI_play_time] = new;
480 stat_client_write_item(SI_play_time);
481 } else
482 free(new);
483 }
484
485 new = daemon_get_uptime_str(now);
486 old = stat_item_values[SI_audiod_uptime];
487 if (force || !old || strcmp(old, new)) {
488 free(old);
489 stat_item_values[SI_audiod_uptime] = new;
490 stat_client_write_item(SI_audiod_uptime);
491 } else
492 free(new);
493
494 old = stat_item_values[SI_audiod_status];
495 new = audiod_status_string();
496 if (force || !old || strcmp(old, new)) {
497 free(old);
498 stat_item_values[SI_audiod_status] = new;
499 stat_client_write_item(SI_audiod_status);
500 } else
501 free(new);
502
503 old = stat_item_values[SI_decoder_flags];
504 new = audiod_get_decoder_flags();
505 if (force || !old || strcmp(old, new)) {
506 free(old);
507 stat_item_values[SI_decoder_flags] = new;
508 stat_client_write_item(SI_decoder_flags);
509 } else
510 free(new);
511 }
512
513 /**
514 * Flush and send all status items.
515 *
516 * Send to each connected client the full status item list
517 * with empty values.
518 */
519 void clear_and_dump_items(void)
520 {
521 int i;
522
523 FOR_EACH_STATUS_ITEM(i) {
524 free(stat_item_values[i]);
525 stat_item_values[i] = NULL;
526 stat_client_write_item(i);
527 }
528 }