spxdec: Use read_u16() from portable_io.h.
[paraslash.git] / afs.c
1 /* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
2
3 /** \file afs.c Paraslash's audio file selector. */
4
5 #include <netinet/in.h>
6 #include <sys/socket.h>
7 #include <regex.h>
8 #include <signal.h>
9 #include <fnmatch.h>
10 #include <osl.h>
11 #include <lopsub.h>
12 #include <arpa/inet.h>
13 #include <sys/un.h>
14 #include <netdb.h>
15 #include <lopsub.h>
16
17 #include "server.lsg.h"
18 #include "server_cmd.lsg.h"
19 #include "para.h"
20 #include "error.h"
21 #include "crypt.h"
22 #include "string.h"
23 #include "afh.h"
24 #include "afs.h"
25 #include "net.h"
26 #include "server.h"
27 #include "ipc.h"
28 #include "list.h"
29 #include "sched.h"
30 #include "fd.h"
31 #include "signal.h"
32 #include "mood.h"
33 #include "sideband.h"
34 #include "command.h"
35
36 /** The osl tables used by afs. \sa \ref blob.c. */
37 enum afs_table_num {
38 /** Contains audio file information. See \ref aft.c. */
39 TBLNUM_AUDIO_FILES,
40 /** The table for the paraslash attributes. See \ref attribute.c. */
41 TBLNUM_ATTRIBUTES,
42 /**
43 * Paraslash's scoring system is based on Gaussian normal
44 * distributions, and the relevant data is stored in the rbtrees of an
45 * osl table containing only volatile columns. See \ref score.c for
46 * details.
47 */
48 TBLNUM_SCORES,
49 /**
50 * A standard blob table containing the mood definitions. For details
51 * see \ref mood.c.
52 */
53 TBLNUM_MOODS,
54 /** A blob table containing lyrics on a per-song basis. */
55 TBLNUM_LYRICS,
56 /** Another blob table for images (for example album cover art). */
57 TBLNUM_IMAGES,
58 /** Yet another blob table for storing standard playlists. */
59 TBLNUM_PLAYLIST,
60 /** How many tables are in use? */
61 NUM_AFS_TABLES
62 };
63
64 static struct afs_table afs_tables[NUM_AFS_TABLES] = {
65 [TBLNUM_AUDIO_FILES] = {.init = aft_init, .name = "audio_files"},
66 [TBLNUM_ATTRIBUTES] = {.init = attribute_init, .name = "attributes"},
67 [TBLNUM_SCORES] = {.init = score_init, .name = "scores"},
68 [TBLNUM_MOODS] = {.init = moods_init, .name = "moods"},
69 [TBLNUM_LYRICS] = {.init = lyrics_init, .name = "lyrics"},
70 [TBLNUM_IMAGES] = {.init = images_init, .name = "images"},
71 [TBLNUM_PLAYLIST] = {.init = playlists_init, .name = "playlists"},
72 };
73
74 struct command_task {
75 /** The file descriptor for the local socket. */
76 int fd;
77 /** The associated task structure. */
78 struct task *task;
79 };
80
81 extern int mmd_mutex;
82 extern struct misc_meta_data *mmd;
83
84 static int server_socket;
85 static struct command_task command_task_struct;
86 static struct signal_task *signal_task;
87
88 static enum play_mode current_play_mode;
89 static char *current_mop; /* mode or playlist specifier. NULL means dummy mood */
90
91 extern uint32_t afs_socket_cookie;
92
93 /**
94 * Struct to let command handlers execute a callback in afs context.
95 *
96 * Commands that need to change the state of afs can't change the relevant data
97 * structures directly because commands are executed in a child process, i.e.
98 * they get their own virtual address space.
99 *
100 * This structure is used by \p send_callback_request() (executed from handler
101 * context) in order to let the afs process call the specified function. An
102 * instance of that structure is written to a shared memory area together with
103 * the arguments to the callback function. The identifier of the shared memory
104 * area is written to the command socket.
105 *
106 * The afs process accepts connections on the command socket and reads the
107 * shared memory id, attaches the corresponding area, calls the given handler to
108 * perform the desired action and to optionally compute a result.
109 *
110 * The result and a \p callback_result structure is then written to another
111 * shared memory area. The identifier for that area is written to the handler's
112 * command socket, so that the handler process can read the id, attach the
113 * shared memory area and use the result.
114 *
115 * \sa \ref struct callback_result.
116 */
117 struct callback_query {
118 /** The function to be called. */
119 afs_callback *handler;
120 /** The number of bytes of the query */
121 size_t query_size;
122 };
123
124 /**
125 * Structure embedded in the result of a callback.
126 *
127 * If the callback produced a result, an instance of that structure is embedded
128 * into the shared memory area holding the result, mainly to let the command
129 * handler know the size of the result.
130 *
131 * \sa \ref struct callback_query.
132 */
133 struct callback_result {
134 /** The number of bytes of the result. */
135 size_t result_size;
136 /** The band designator (loglevel for the result). */
137 uint8_t band;
138 };
139
140 static int dispatch_result(int result_shmid, callback_result_handler *handler,
141 void *private_result_data)
142 {
143 struct osl_object result;
144 void *result_shm;
145 /* must attach r/w as result.data might get encrypted in-place. */
146 int ret2, ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
147 struct callback_result *cr = result_shm;
148
149 if (ret < 0) {
150 PARA_ERROR_LOG("attach failed: %s\n", para_strerror(-ret));
151 return ret;
152 }
153 result.size = cr->result_size;
154 result.data = result_shm + sizeof(*cr);
155 assert(handler);
156 ret = handler(&result, cr->band, private_result_data);
157 ret2 = shm_detach(result_shm);
158 if (ret2 < 0) {
159 PARA_ERROR_LOG("detach failed: %s\n", para_strerror(-ret2));
160 if (ret >= 0)
161 ret = ret2;
162 }
163 return ret;
164 }
165
166 /**
167 * Ask the afs process to call a given function.
168 *
169 * \param f The function to be called.
170 * \param query Pointer to arbitrary data for the callback.
171 * \param result_handler Called for each shm area sent by the callback.
172 * \param private_result_data Passed verbatim to \a result_handler.
173 *
174 * This function creates a socket for communication with the afs process and a
175 * shared memory area (sma) to which the buffer pointed to by \a query is
176 * copied. It then notifies the afs process that the callback function \a f
177 * should be executed by sending the shared memory identifier (shmid) to the
178 * socket.
179 *
180 * If the callback produces a result, it sends any number of shared memory
181 * identifiers back via the socket. For each such identifier received, \a
182 * result_handler is called. The contents of the sma identified by the received
183 * shmid are passed to that function as an osl object. The private_result_data
184 * pointer is passed as the second argument to \a result_handler.
185 *
186 * \return Number of shared memory areas dispatched on success, negative on
187 * errors.
188 */
189 int send_callback_request(afs_callback *f, struct osl_object *query,
190 callback_result_handler *result_handler,
191 void *private_result_data)
192 {
193 struct callback_query *cq;
194 int ret, fd = -1, query_shmid, result_shmid;
195 void *query_shm;
196 char buf[sizeof(afs_socket_cookie) + sizeof(int)];
197 size_t query_shm_size = sizeof(*cq);
198 int dispatch_error = 0, num_dispatched = 0;
199
200 if (query)
201 query_shm_size += query->size;
202 ret = shm_new(query_shm_size);
203 if (ret < 0)
204 return ret;
205 query_shmid = ret;
206 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
207 if (ret < 0)
208 goto out;
209 cq = query_shm;
210 cq->handler = f;
211 cq->query_size = query_shm_size - sizeof(*cq);
212
213 if (query)
214 memcpy(query_shm + sizeof(*cq), query->data, query->size);
215 ret = shm_detach(query_shm);
216 if (ret < 0)
217 goto out;
218
219 *(uint32_t *)buf = afs_socket_cookie;
220 *(int *)(buf + sizeof(afs_socket_cookie)) = query_shmid;
221
222 ret = connect_local_socket(OPT_STRING_VAL(AFS_SOCKET));
223 if (ret < 0)
224 goto out;
225 fd = ret;
226 ret = write_all(fd, buf, sizeof(buf));
227 if (ret < 0)
228 goto out;
229 /*
230 * Read all shmids from afs.
231 *
232 * Even if the dispatcher returns an error we _must_ continue to read
233 * shmids from fd so that we can destroy all shared memory areas that
234 * have been created for us by the afs process.
235 */
236 for (;;) {
237 ret = recv_bin_buffer(fd, buf, sizeof(int));
238 if (ret <= 0)
239 goto out;
240 assert(ret == sizeof(int));
241 ret = *(int *) buf;
242 assert(ret > 0);
243 result_shmid = ret;
244 ret = dispatch_result(result_shmid, result_handler,
245 private_result_data);
246 if (ret < 0 && dispatch_error >= 0)
247 dispatch_error = ret;
248 ret = shm_destroy(result_shmid);
249 if (ret < 0)
250 PARA_CRIT_LOG("destroy result failed: %s\n",
251 para_strerror(-ret));
252 num_dispatched++;
253 }
254 out:
255 if (shm_destroy(query_shmid) < 0)
256 PARA_CRIT_LOG("shm destroy error\n");
257 if (fd >= 0)
258 close(fd);
259 if (dispatch_error < 0)
260 return dispatch_error;
261 if (ret < 0)
262 return ret;
263 return num_dispatched;
264 }
265
266 /**
267 * Wrapper for send_callback_request() which passes a lopsub parse result.
268 *
269 * \param f The callback function.
270 * \param cmd Needed for (de-)serialization.
271 * \param lpr Must match cmd.
272 * \param private_result_data Passed to send_callback_request().
273 *
274 * This function serializes the parse result given by the lpr pointer into a
275 * buffer. The buffer is sent as the query to the afs process with the callback
276 * mechanism.
277 *
278 * \return The return value of the underlying call to send_callback_request().
279 */
280 int send_lls_callback_request(afs_callback *f,
281 const struct lls_command * const cmd,
282 struct lls_parse_result *lpr, void *private_result_data)
283 {
284 struct osl_object query;
285 char *buf = NULL;
286 int ret = lls_serialize_parse_result(lpr, cmd, &buf, &query.size);
287
288 assert(ret >= 0);
289 query.data = buf;
290 ret = send_callback_request(f, &query, afs_cb_result_handler,
291 private_result_data);
292 free(buf);
293 return ret;
294 }
295
296 static int action_if_pattern_matches(struct osl_row *row, void *data)
297 {
298 struct pattern_match_data *pmd = data;
299 struct osl_object name_obj;
300 const char *p, *name;
301 int i, ret;
302
303 ret = osl(osl_get_object(pmd->table, row, pmd->match_col_num,
304 &name_obj));
305 if (ret < 0)
306 return ret;
307 name = (char *)name_obj.data;
308 if ((!name || !*name) && (pmd->pm_flags & PM_SKIP_EMPTY_NAME))
309 return 1;
310 if (lls_num_inputs(pmd->lpr) == 0) {
311 if (pmd->pm_flags & PM_NO_PATTERN_MATCHES_EVERYTHING) {
312 pmd->num_matches++;
313 return pmd->action(pmd->table, row, name, pmd->data);
314 }
315 }
316 i = pmd->input_skip;
317 for (;;) {
318 if (i >= lls_num_inputs(pmd->lpr))
319 break;
320 p = lls_input(i, pmd->lpr);
321 ret = fnmatch(p, name, pmd->fnmatch_flags);
322 if (ret != FNM_NOMATCH) {
323 if (ret != 0)
324 return -E_FNMATCH;
325 ret = pmd->action(pmd->table, row, name, pmd->data);
326 if (ret >= 0)
327 pmd->num_matches++;
328 return ret;
329
330 }
331 i++;
332 }
333 return 1;
334 }
335
336 /**
337 * Execute the given function for each matching row.
338 *
339 * \param pmd Describes what to match and how.
340 *
341 * \return Standard.
342 */
343 int for_each_matching_row(struct pattern_match_data *pmd)
344 {
345 if (pmd->pm_flags & PM_REVERSE_LOOP)
346 return osl(osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
347 action_if_pattern_matches));
348 return osl(osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
349 action_if_pattern_matches));
350 }
351
352 /**
353 * Compare two osl objects of string type.
354 *
355 * \param obj1 Pointer to the first object.
356 * \param obj2 Pointer to the second object.
357 *
358 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
359 * are taken into account.
360 *
361 * \return It returns an integer less than, equal to, or greater than zero if
362 * \a obj1 is found, respectively, to be less than, to match, or be greater than
363 * obj2.
364 *
365 * \sa strcmp(3), strncmp(3).
366 */
367 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
368 {
369 const char *str1 = (const char *)obj1->data;
370 const char *str2 = (const char *)obj2->data;
371 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
372 }
373
374 static int pass_afd(int fd, char *buf, size_t size)
375 {
376 struct msghdr msg = {.msg_iov = NULL};
377 struct cmsghdr *cmsg;
378 char control[255] __a_aligned(8);
379 int ret;
380 struct iovec iov;
381
382 iov.iov_base = buf;
383 iov.iov_len = size;
384
385 msg.msg_iov = &iov;
386 msg.msg_iovlen = 1;
387
388 msg.msg_control = control;
389 msg.msg_controllen = sizeof(control);
390
391 cmsg = CMSG_FIRSTHDR(&msg);
392 cmsg->cmsg_level = SOL_SOCKET;
393 cmsg->cmsg_type = SCM_RIGHTS;
394 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
395 *(int *)CMSG_DATA(cmsg) = fd;
396
397 /* Sum of the length of all control messages in the buffer */
398 msg.msg_controllen = cmsg->cmsg_len;
399 PARA_DEBUG_LOG("passing %zu bytes and fd %d\n", size, fd);
400 ret = sendmsg(server_socket, &msg, 0);
401 if (ret < 0) {
402 ret = -ERRNO_TO_PARA_ERROR(errno);
403 return ret;
404 }
405 return 1;
406 }
407
408 /**
409 * Pass the fd of the next audio file to the server process.
410 *
411 * This stores all information for streaming the "best" audio file in a shared
412 * memory area. The id of that area and an open file descriptor for the next
413 * audio file are passed to the server process.
414 *
415 * \return Standard.
416 *
417 * \sa \ref open_and_update_audio_file().
418 */
419 static int open_next_audio_file(void)
420 {
421 struct audio_file_data afd;
422 int ret, shmid;
423 char buf[8];
424
425 ret = open_and_update_audio_file(&afd);
426 if (ret < 0) {
427 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
428 goto no_admissible_files;
429 }
430 shmid = ret;
431 if (!write_ok(server_socket)) {
432 ret = -E_AFS_SOCKET;
433 goto destroy;
434 }
435 *(uint32_t *)buf = NEXT_AUDIO_FILE;
436 *(uint32_t *)(buf + 4) = (uint32_t)shmid;
437 ret = pass_afd(afd.fd, buf, 8);
438 close(afd.fd);
439 if (ret >= 0)
440 return ret;
441 destroy:
442 shm_destroy(shmid);
443 return ret;
444 no_admissible_files:
445 *(uint32_t *)buf = NO_ADMISSIBLE_FILES;
446 *(uint32_t *)(buf + 4) = (uint32_t)0;
447 return write_all(server_socket, buf, 8);
448 }
449
450 /* Never fails if arg == NULL */
451 static int activate_mood_or_playlist(const char *arg, int *num_admissible,
452 char **errmsg)
453 {
454 enum play_mode mode;
455 int ret;
456
457 if (!arg) {
458 ret = change_current_mood(NULL, NULL); /* always successful */
459 mode = PLAY_MODE_MOOD;
460 } else {
461 if (!strncmp(arg, "p/", 2)) {
462 ret = playlist_open(arg + 2);
463 if (ret < 0 && errmsg)
464 *errmsg = make_message( "could not open %s",
465 arg);
466 mode = PLAY_MODE_PLAYLIST;
467 } else if (!strncmp(arg, "m/", 2)) {
468 ret = change_current_mood(arg + 2, errmsg);
469 mode = PLAY_MODE_MOOD;
470 } else {
471 if (errmsg)
472 *errmsg = make_message("%s: parse error", arg);
473 return -ERRNO_TO_PARA_ERROR(EINVAL);
474 }
475 if (ret < 0)
476 return ret;
477 }
478 if (num_admissible)
479 *num_admissible = ret;
480 current_play_mode = mode;
481 if (arg != current_mop) {
482 free(current_mop);
483 if (arg) {
484 current_mop = para_strdup(arg);
485 mutex_lock(mmd_mutex);
486 strncpy(mmd->afs_mode_string, arg,
487 sizeof(mmd->afs_mode_string));
488 mmd->afs_mode_string[sizeof(mmd->afs_mode_string) - 1] = '\0';
489 mmd->events++;
490 mutex_unlock(mmd_mutex);
491 } else {
492 mutex_lock(mmd_mutex);
493 strcpy(mmd->afs_mode_string, "dummy");
494 mmd->events++;
495 mutex_unlock(mmd_mutex);
496 current_mop = NULL;
497 }
498 }
499 return 1;
500 }
501
502 /**
503 * Result handler for sending data to the para_client process.
504 *
505 * \param result The data to be sent.
506 * \param band The band designator.
507 * \param private Pointer to the command context.
508 *
509 * \return The return value of the underlying call to \ref command.c::send_sb.
510 *
511 * \sa \ref callback_result_handler, \ref command.c::send_sb.
512 */
513 int afs_cb_result_handler(struct osl_object *result, uint8_t band,
514 void *private)
515 {
516 struct command_context *cc = private;
517
518 assert(cc);
519 switch (band) {
520 case SBD_OUTPUT:
521 case SBD_DEBUG_LOG:
522 case SBD_INFO_LOG:
523 case SBD_NOTICE_LOG:
524 case SBD_WARNING_LOG:
525 case SBD_ERROR_LOG:
526 case SBD_CRIT_LOG:
527 case SBD_EMERG_LOG:
528 assert(result->size > 0);
529 return send_sb(&cc->scc, result->data, result->size, band, true);
530 case SBD_AFS_CB_FAILURE:
531 return *(int *)(result->data);
532 default:
533 return -E_BAD_BAND;
534 }
535 }
536
537 static void flush_and_free_pb(struct para_buffer *pb)
538 {
539 int ret;
540 struct afs_max_size_handler_data *amshd = pb->private_data;
541
542 if (pb->buf && pb->size > 0) {
543 ret = pass_buffer_as_shm(amshd->fd, amshd->band, pb->buf,
544 pb->offset);
545 if (ret < 0)
546 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
547 }
548 free(pb->buf);
549 }
550
551 static int com_select_callback(struct afs_callback_arg *aca)
552 {
553 const struct lls_command *cmd = SERVER_CMD_CMD_PTR(SELECT);
554 const char *arg;
555 int num_admissible, ret;
556 char *errmsg;
557
558 ret = lls_deserialize_parse_result(aca->query.data, cmd, &aca->lpr);
559 assert(ret >= 0);
560 arg = lls_input(0, aca->lpr);
561 ret = clear_score_table();
562 if (ret < 0) {
563 para_printf(&aca->pbout, "could not clear score table\n");
564 goto free_lpr;
565 }
566 if (current_play_mode == PLAY_MODE_MOOD)
567 close_current_mood();
568 else
569 playlist_close();
570 ret = activate_mood_or_playlist(arg, &num_admissible, &errmsg);
571 if (ret >= 0)
572 goto out;
573 /* ignore subsequent errors (but log them) */
574 para_printf(&aca->pbout, "%s\n", errmsg);
575 free(errmsg);
576 para_printf(&aca->pbout, "could not activate %s\n", arg);
577 if (current_mop && strcmp(current_mop, arg) != 0) {
578 int ret2;
579 para_printf(&aca->pbout, "switching back to %s\n", current_mop);
580 ret2 = activate_mood_or_playlist(current_mop, &num_admissible,
581 &errmsg);
582 if (ret2 >= 0)
583 goto out;
584 para_printf(&aca->pbout, "%s\n", errmsg);
585 free(errmsg);
586 para_printf(&aca->pbout, "could not reactivate %s: %s\n",
587 current_mop, para_strerror(-ret2));
588 }
589 para_printf(&aca->pbout, "activating dummy mood\n");
590 activate_mood_or_playlist(NULL, &num_admissible, NULL);
591 out:
592 para_printf(&aca->pbout, "activated %s (%d admissible files)\n",
593 current_mop? current_mop : "dummy mood", num_admissible);
594 free_lpr:
595 lls_free_parse_result(aca->lpr, cmd);
596 return ret;
597 }
598
599 static int com_select(struct command_context *cc, struct lls_parse_result *lpr)
600 {
601 const struct lls_command *cmd = SERVER_CMD_CMD_PTR(SELECT);
602 char *errctx;
603 int ret = lls(lls_check_arg_count(lpr, 1, 1, &errctx));
604
605 if (ret < 0) {
606 send_errctx(cc, errctx);
607 return ret;
608 }
609 return send_lls_callback_request(com_select_callback, cmd, lpr, cc);
610 }
611 EXPORT_SERVER_CMD_HANDLER(select);
612
613 static void init_admissible_files(const char *arg)
614 {
615 int ret = activate_mood_or_playlist(arg, NULL, NULL);
616 if (ret < 0) {
617 assert(arg);
618 PARA_WARNING_LOG("could not activate %s: %s\n", arg,
619 para_strerror(-ret));
620 activate_mood_or_playlist(NULL, NULL, NULL);
621 }
622 }
623
624 static int setup_command_socket_or_die(void)
625 {
626 int ret, socket_fd;
627 const char *socket_name = OPT_STRING_VAL(AFS_SOCKET);
628
629 unlink(socket_name);
630 ret = create_local_socket(socket_name);
631 if (ret < 0) {
632 PARA_EMERG_LOG("%s: %s\n", para_strerror(-ret), socket_name);
633 exit(EXIT_FAILURE);
634 }
635 socket_fd = ret;
636 PARA_INFO_LOG("listening on socket %s (fd %d)\n", socket_name,
637 socket_fd);
638 return socket_fd;
639 }
640
641 static char *database_dir;
642
643 static void close_afs_tables(void)
644 {
645 int i;
646 PARA_NOTICE_LOG("closing afs_tables\n");
647 for (i = 0; i < NUM_AFS_TABLES; i++)
648 afs_tables[i].close();
649 free(database_dir);
650 database_dir = NULL;
651 }
652
653 static void get_database_dir(void)
654 {
655 if (!database_dir) {
656 if (OPT_GIVEN(AFS_DATABASE_DIR))
657 database_dir = para_strdup(OPT_STRING_VAL(AFS_DATABASE_DIR));
658 else {
659 char *home = para_homedir();
660 database_dir = make_message(
661 "%s/.paraslash/afs_database-0.4", home);
662 free(home);
663 }
664 }
665 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
666 }
667
668 static int make_database_dir(void)
669 {
670 int ret;
671
672 get_database_dir();
673 ret = para_mkdir(database_dir, 0777);
674 if (ret >= 0 || ret == -ERRNO_TO_PARA_ERROR(EEXIST))
675 return 1;
676 return ret;
677 }
678
679 static int open_afs_tables(void)
680 {
681 int i, ret;
682
683 get_database_dir();
684 PARA_NOTICE_LOG("opening %d osl tables in %s\n", NUM_AFS_TABLES,
685 database_dir);
686 for (i = 0; i < NUM_AFS_TABLES; i++) {
687 ret = afs_tables[i].open(database_dir);
688 if (ret >= 0)
689 continue;
690 PARA_ERROR_LOG("could not open %s\n", afs_tables[i].name);
691 break;
692 }
693 if (ret >= 0)
694 return ret;
695 while (i)
696 afs_tables[--i].close();
697 return ret;
698 }
699
700 static int afs_signal_post_select(struct sched *s, __a_unused void *context)
701 {
702 int signum, ret;
703
704 if (getppid() == 1) {
705 PARA_EMERG_LOG("para_server died\n");
706 goto shutdown;
707 }
708 signum = para_next_signal(&s->rfds);
709 if (signum == 0)
710 return 0;
711 if (signum == SIGHUP) {
712 close_afs_tables();
713 parse_config_or_die(1);
714 ret = open_afs_tables();
715 if (ret < 0)
716 return ret;
717 init_admissible_files(current_mop);
718 return 0;
719 }
720 PARA_EMERG_LOG("terminating on signal %d\n", signum);
721 shutdown:
722 task_notify_all(s, E_AFS_SIGNAL);
723 return -E_AFS_SIGNAL;
724 }
725
726 static void register_signal_task(struct sched *s)
727 {
728 para_sigaction(SIGPIPE, SIG_IGN);
729 signal_task = signal_init_or_die();
730 para_install_sighandler(SIGINT);
731 para_install_sighandler(SIGTERM);
732 para_install_sighandler(SIGHUP);
733
734 signal_task->task = task_register(&(struct task_info) {
735 .name = "signal",
736 .pre_select = signal_pre_select,
737 .post_select = afs_signal_post_select,
738 .context = signal_task,
739
740 }, s);
741 }
742
743 static struct list_head afs_client_list;
744
745 /** Describes one connected afs client. */
746 struct afs_client {
747 /** Position in the afs client list. */
748 struct list_head node;
749 /** The socket file descriptor for this client. */
750 int fd;
751 /** The time the client connected. */
752 struct timeval connect_time;
753 };
754
755 static void command_pre_select(struct sched *s, void *context)
756 {
757 struct command_task *ct = context;
758 struct afs_client *client;
759
760 para_fd_set(server_socket, &s->rfds, &s->max_fileno);
761 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
762 list_for_each_entry(client, &afs_client_list, node)
763 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
764 }
765
766 /**
767 * Send data as shared memory to a file descriptor.
768 *
769 * \param fd File descriptor to send the shmid to.
770 * \param band The band designator for this data.
771 * \param buf The buffer holding the data to be sent.
772 * \param size The size of \a buf.
773 *
774 * This function creates a shared memory area large enough to hold
775 * the content given by \a buf and \a size and sends the identifier
776 * of this area to the file descriptor \a fd.
777 *
778 * It is called by the AFS max_size handler as well as directly by the AFS
779 * command callbacks to send command output to the command handlers.
780 *
781 * \return Zero if \a buf is \p NULL or \a size is zero. Negative on errors,
782 * and positive on success.
783 */
784 int pass_buffer_as_shm(int fd, uint8_t band, const char *buf, size_t size)
785 {
786 int ret, shmid;
787 void *shm;
788 struct callback_result *cr;
789
790 if (size == 0)
791 assert(band != SBD_OUTPUT);
792 ret = shm_new(size + sizeof(*cr));
793 if (ret < 0)
794 return ret;
795 shmid = ret;
796 ret = shm_attach(shmid, ATTACH_RW, &shm);
797 if (ret < 0)
798 goto err;
799 cr = shm;
800 cr->result_size = size;
801 cr->band = band;
802 if (size > 0)
803 memcpy(shm + sizeof(*cr), buf, size);
804 ret = shm_detach(shm);
805 if (ret < 0)
806 goto err;
807 ret = write_all(fd, (char *)&shmid, sizeof(int));
808 if (ret >= 0)
809 return ret;
810 err:
811 if (shm_destroy(shmid) < 0)
812 PARA_ERROR_LOG("destroy result failed\n");
813 return ret;
814 }
815
816 static int call_callback(int fd, int query_shmid)
817 {
818 void *query_shm;
819 struct callback_query *cq;
820 int ret, ret2;
821 struct afs_callback_arg aca = {.fd = fd};
822
823 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
824 if (ret < 0)
825 return ret;
826 cq = query_shm;
827 aca.query.data = (char *)query_shm + sizeof(*cq);
828 aca.query.size = cq->query_size;
829 aca.pbout.max_size = shm_get_shmmax();
830 aca.pbout.max_size_handler = afs_max_size_handler;
831 aca.pbout.private_data = &(struct afs_max_size_handler_data) {
832 .fd = fd,
833 .band = SBD_OUTPUT
834 };
835 ret = cq->handler(&aca);
836 ret2 = shm_detach(query_shm);
837 if (ret2 < 0) {
838 if (ret < 0) /* ignore (but log) detach error */
839 PARA_ERROR_LOG("could not detach sma: %s\n",
840 para_strerror(-ret2));
841 else
842 ret = ret2;
843 }
844 flush_and_free_pb(&aca.pbout);
845 if (ret < 0) {
846 ret2 = pass_buffer_as_shm(fd, SBD_AFS_CB_FAILURE,
847 (const char *)&ret, sizeof(ret));
848 if (ret2 < 0)
849 PARA_ERROR_LOG("could not pass cb failure packet: %s\n",
850 para_strerror(-ret));
851 }
852 return ret;
853 }
854
855 static int execute_server_command(fd_set *rfds)
856 {
857 char buf[8];
858 size_t n;
859 int ret = read_nonblock(server_socket, buf, sizeof(buf) - 1, rfds, &n);
860
861 if (ret < 0 || n == 0)
862 return ret;
863 buf[n] = '\0';
864 if (strcmp(buf, "new"))
865 return -ERRNO_TO_PARA_ERROR(EINVAL);
866 return open_next_audio_file();
867 }
868
869 /* returns 0 if no data available, 1 else */
870 static int execute_afs_command(int fd, fd_set *rfds)
871 {
872 uint32_t cookie;
873 int query_shmid;
874 char buf[sizeof(cookie) + sizeof(query_shmid)];
875 size_t n;
876 int ret = read_nonblock(fd, buf, sizeof(buf), rfds, &n);
877
878 if (ret < 0)
879 goto err;
880 if (n == 0)
881 return 0;
882 if (n != sizeof(buf)) {
883 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
884 ret, (long unsigned) sizeof(buf));
885 return 1;
886 }
887 cookie = *(uint32_t *)buf;
888 if (cookie != afs_socket_cookie) {
889 PARA_NOTICE_LOG("received invalid cookie (got %u, expected %u)\n",
890 (unsigned)cookie, (unsigned)afs_socket_cookie);
891 return 1;
892 }
893 query_shmid = *(int *)(buf + sizeof(cookie));
894 if (query_shmid < 0) {
895 PARA_WARNING_LOG("received invalid query shmid %d)\n",
896 query_shmid);
897 return 1;
898 }
899 ret = call_callback(fd, query_shmid);
900 if (ret >= 0)
901 return 1;
902 err:
903 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
904 return 1;
905 }
906
907 /** Shutdown connection if query has not arrived until this many seconds. */
908 #define AFS_CLIENT_TIMEOUT 3
909
910 static int command_post_select(struct sched *s, void *context)
911 {
912 struct command_task *ct = context;
913 struct sockaddr_un unix_addr;
914 struct afs_client *client, *tmp;
915 int fd, ret;
916
917 ret = task_get_notification(ct->task);
918 if (ret < 0)
919 return ret;
920 ret = execute_server_command(&s->rfds);
921 if (ret < 0) {
922 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
923 task_notify_all(s, -ret);
924 return ret;
925 }
926 /* Check the list of connected clients. */
927 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
928 ret = execute_afs_command(client->fd, &s->rfds);
929 if (ret == 0) { /* prevent bogus connection flooding */
930 struct timeval diff;
931 tv_diff(now, &client->connect_time, &diff);
932 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
933 continue;
934 PARA_WARNING_LOG("connection timeout\n");
935 }
936 close(client->fd);
937 list_del(&client->node);
938 free(client);
939 }
940 /* Accept connections on the local socket. */
941 ret = para_accept(ct->fd, &s->rfds, &unix_addr, sizeof(unix_addr), &fd);
942 if (ret < 0)
943 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
944 if (ret <= 0)
945 return 0;
946 ret = mark_fd_nonblocking(fd);
947 if (ret < 0) {
948 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
949 close(fd);
950 return 0;
951 }
952 client = para_malloc(sizeof(*client));
953 client->fd = fd;
954 client->connect_time = *now;
955 para_list_add(&client->node, &afs_client_list);
956 return 0;
957 }
958
959 static void register_command_task(struct sched *s)
960 {
961 struct command_task *ct = &command_task_struct;
962 ct->fd = setup_command_socket_or_die();
963
964 ct->task = task_register(&(struct task_info) {
965 .name = "afs command",
966 .pre_select = command_pre_select,
967 .post_select = command_post_select,
968 .context = ct,
969 }, s);
970 }
971
972 /**
973 * Initialize the audio file selector process.
974 *
975 * \param socket_fd File descriptor used for communication with the server.
976 */
977 __noreturn void afs_init(int socket_fd)
978 {
979 static struct sched s;
980 int i, ret;
981
982 register_signal_task(&s);
983 INIT_LIST_HEAD(&afs_client_list);
984 for (i = 0; i < NUM_AFS_TABLES; i++)
985 afs_tables[i].init(&afs_tables[i]);
986 ret = open_afs_tables();
987 if (ret < 0)
988 goto out;
989 server_socket = socket_fd;
990 ret = mark_fd_nonblocking(server_socket);
991 if (ret < 0)
992 goto out_close;
993 PARA_INFO_LOG("server_socket: %d\n", server_socket);
994 init_admissible_files(OPT_STRING_VAL(AFS_INITIAL_MODE));
995 register_command_task(&s);
996 s.default_timeout.tv_sec = 0;
997 s.default_timeout.tv_usec = 999 * 1000;
998 ret = write(socket_fd, "\0", 1);
999 if (ret != 1) {
1000 if (ret == 0)
1001 errno = EINVAL;
1002 ret = -ERRNO_TO_PARA_ERROR(errno);
1003 goto out_close;
1004 }
1005 ret = schedule(&s);
1006 sched_shutdown(&s);
1007 close_current_mood();
1008 out_close:
1009 close_afs_tables();
1010 out:
1011 signal_shutdown(signal_task);
1012 free_status_items();
1013 free(current_mop);
1014 free_lpr();
1015 if (ret < 0)
1016 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1017 exit(EXIT_FAILURE);
1018 }
1019
1020 static int com_init_callback(struct afs_callback_arg *aca)
1021 {
1022 uint32_t table_mask = *(uint32_t *)aca->query.data;
1023 int i, ret;
1024
1025 close_afs_tables();
1026 get_database_dir();
1027 for (i = 0; i < NUM_AFS_TABLES; i++) {
1028 struct afs_table *t = &afs_tables[i];
1029
1030 if (!(table_mask & (1 << i)))
1031 continue;
1032 if (!t->create)
1033 continue;
1034 ret = t->create(database_dir);
1035 if (ret < 0) {
1036 para_printf(&aca->pbout, "cannot create table %s\n",
1037 t->name);
1038 goto out;
1039 }
1040 para_printf(&aca->pbout, "successfully created %s table\n",
1041 t->name);
1042 }
1043 ret = open_afs_tables();
1044 if (ret < 0)
1045 para_printf(&aca->pbout, "cannot open afs tables\n");
1046 out:
1047 return ret;
1048 }
1049
1050 static int com_init(struct command_context *cc, struct lls_parse_result *lpr)
1051 {
1052 int i, j, ret;
1053 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
1054 struct osl_object query = {.data = &table_mask,
1055 .size = sizeof(table_mask)};
1056 unsigned num_inputs = lls_num_inputs(lpr);
1057
1058 ret = make_database_dir();
1059 if (ret < 0)
1060 return ret;
1061 if (num_inputs > 0) {
1062 table_mask = 0;
1063 for (i = 0; i < num_inputs; i++) {
1064 for (j = 0; j < NUM_AFS_TABLES; j++) {
1065 struct afs_table *t = &afs_tables[j];
1066
1067 if (strcmp(lls_input(i, lpr), t->name))
1068 continue;
1069 table_mask |= (1 << j);
1070 break;
1071 }
1072 if (j == NUM_AFS_TABLES)
1073 return -E_BAD_TABLE_NAME;
1074 }
1075 }
1076 return send_callback_request(com_init_callback, &query,
1077 afs_cb_result_handler, cc);
1078 }
1079 EXPORT_SERVER_CMD_HANDLER(init);
1080
1081 static int com_check(struct command_context *cc, struct lls_parse_result *lpr)
1082 {
1083 const struct lls_opt_result *r_a = SERVER_CMD_OPT_RESULT(CHECK, AFT, lpr);
1084 const struct lls_opt_result *r_A = SERVER_CMD_OPT_RESULT(CHECK, ATTRIBUTE, lpr);
1085 const struct lls_opt_result *r_m = SERVER_CMD_OPT_RESULT(CHECK, MOOD, lpr);
1086 const struct lls_opt_result *r_p = SERVER_CMD_OPT_RESULT(CHECK, PLAYLIST, lpr);
1087 bool noopt = !lls_opt_given(r_a) && !lls_opt_given(r_A)
1088 && !lls_opt_given(r_m) && !lls_opt_given(r_p);
1089 int ret;
1090
1091 if (noopt || lls_opt_given(r_a)) {
1092 ret = send_callback_request(aft_check_callback, NULL,
1093 afs_cb_result_handler, cc);
1094 if (ret < 0)
1095 return ret;
1096 }
1097 if (noopt || lls_opt_given(r_A)) {
1098 ret = send_callback_request(attribute_check_callback, NULL,
1099 afs_cb_result_handler, cc);
1100 if (ret < 0)
1101 return ret;
1102 }
1103 if (noopt || lls_opt_given(r_p)) {
1104 ret = send_callback_request(playlist_check_callback,
1105 NULL, afs_cb_result_handler, cc);
1106 if (ret < 0)
1107 return ret;
1108 }
1109 if (noopt || lls_opt_given(r_m)) {
1110 ret = send_callback_request(mood_check_callback, NULL,
1111 afs_cb_result_handler, cc);
1112 if (ret < 0)
1113 return ret;
1114 }
1115 return 1;
1116 }
1117 EXPORT_SERVER_CMD_HANDLER(check);
1118
1119 /**
1120 * The afs event dispatcher.
1121 *
1122 * \param event Type of the event.
1123 * \param pb May be \p NULL.
1124 * \param data Type depends on \a event.
1125 *
1126 * This function calls each table event handler, passing \a pb and \a data
1127 * verbatim. It's up to the handlers to interpret the \a data pointer. If a
1128 * handler returns negative, the loop is aborted.
1129 *
1130 * \return The (negative) error code of the first handler that failed, or non-negative
1131 * if all handlers succeeded.
1132 */
1133 __must_check int afs_event(enum afs_events event, struct para_buffer *pb,
1134 void *data)
1135 {
1136 int i, ret;
1137
1138 for (i = 0; i < NUM_AFS_TABLES; i++) {
1139 struct afs_table *t = &afs_tables[i];
1140 if (!t->event_handler)
1141 continue;
1142 ret = t->event_handler(event, pb, data);
1143 if (ret < 0) {
1144 PARA_CRIT_LOG("table %s, event %u: %s\n", t->name,
1145 event, para_strerror(-ret));
1146 return ret;
1147 }
1148 }
1149 return 1;
1150 }
1151
1152 /**
1153 * Dummy event handler for the images table.
1154 *
1155 * \param event Unused.
1156 * \param pb Unused.
1157 * \param data Unused.
1158 *
1159 * \return The images table does not honor events, so this handler always
1160 * returns success.
1161 */
1162 __a_const int images_event_handler(__a_unused enum afs_events event,
1163 __a_unused struct para_buffer *pb, __a_unused void *data)
1164 {
1165 return 1;
1166 }
1167
1168 /**
1169 * Dummy event handler for the lyrics table.
1170 *
1171 * \param event Unused.
1172 * \param pb Unused.
1173 * \param data Unused.
1174 *
1175 * \return The lyrics table does not honor events, so this handler always
1176 * returns success.
1177 */
1178 __a_const int lyrics_event_handler(__a_unused enum afs_events event,
1179 __a_unused struct para_buffer *pb, __a_unused void *data)
1180 {
1181 return 1;
1182 }