Merge branch 'refs/heads/t/xz'
[paraslash.git] / afs.c
1 /*
2 * Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file afs.c Paraslash's audio file selector. */
8
9 #include <netinet/in.h>
10 #include <sys/socket.h>
11 #include <regex.h>
12 #include <signal.h>
13 #include <fnmatch.h>
14 #include <osl.h>
15 #include <arpa/inet.h>
16 #include <sys/un.h>
17 #include <netdb.h>
18
19 #include "server.cmdline.h"
20 #include "para.h"
21 #include "error.h"
22 #include "crypt.h"
23 #include "string.h"
24 #include "afh.h"
25 #include "afs.h"
26 #include "server.h"
27 #include "net.h"
28 #include "ipc.h"
29 #include "list.h"
30 #include "sched.h"
31 #include "fd.h"
32 #include "signal.h"
33 #include "mood.h"
34 #include "sideband.h"
35 #include "command.h"
36
37 /** The osl tables used by afs. \sa blob.c. */
38 enum afs_table_num {
39 /** Contains audio file information. See aft.c. */
40 TBLNUM_AUDIO_FILES,
41 /** The table for the paraslash attributes. See attribute.c. */
42 TBLNUM_ATTRIBUTES,
43 /**
44 * Paraslash's scoring system is based on Gaussian normal
45 * distributions, and the relevant data is stored in the rbtrees of an
46 * osl table containing only volatile columns. See score.c for
47 * details.
48 */
49 TBLNUM_SCORES,
50 /**
51 * A standard blob table containing the mood definitions. For details
52 * see mood.c.
53 */
54 TBLNUM_MOODS,
55 /** A blob table containing lyrics on a per-song basis. */
56 TBLNUM_LYRICS,
57 /** Another blob table for images (for example album cover art). */
58 TBLNUM_IMAGES,
59 /** Yet another blob table for storing standard playlists. */
60 TBLNUM_PLAYLIST,
61 /** How many tables are in use? */
62 NUM_AFS_TABLES
63 };
64
65 static struct afs_table afs_tables[NUM_AFS_TABLES] = {
66 [TBLNUM_AUDIO_FILES] = {.init = aft_init, .name = "audio_files"},
67 [TBLNUM_ATTRIBUTES] = {.init = attribute_init, .name = "attributes"},
68 [TBLNUM_SCORES] = {.init = score_init, .name = "scores"},
69 [TBLNUM_MOODS] = {.init = moods_init, .name = "moods"},
70 [TBLNUM_LYRICS] = {.init = lyrics_init, .name = "lyrics"},
71 [TBLNUM_IMAGES] = {.init = images_init, .name = "images"},
72 [TBLNUM_PLAYLIST] = {.init = playlists_init, .name = "playlists"},
73 };
74
75 struct command_task {
76 /** The file descriptor for the local socket. */
77 int fd;
78 /**
79 * Value sent by the command handlers to identify themselves as
80 * children of the running para_server.
81 */
82 uint32_t cookie;
83 /** The associated task structure. */
84 struct task *task;
85 };
86
87 extern int mmd_mutex;
88 extern struct misc_meta_data *mmd;
89
90 static int server_socket;
91 static struct command_task command_task_struct;
92 static struct signal_task *signal_task;
93
94 static enum play_mode current_play_mode;
95 static char *current_mop; /* mode or playlist specifier. NULL means dummy mood */
96
97 /**
98 * A random number used to "authenticate" the connection.
99 *
100 * para_server picks this number by random before it forks the afs process. The
101 * command handlers know this number as well and write it to the afs socket,
102 * together with the id of the shared memory area which contains the payload of
103 * the afs command. A local process has to know this number to abuse the afs
104 * service provided by the local socket.
105 */
106 extern uint32_t afs_socket_cookie;
107
108 /**
109 * Struct to let command handlers execute a callback in afs context.
110 *
111 * Commands that need to change the state of afs can't change the relevant data
112 * structures directly because commands are executed in a child process, i.e.
113 * they get their own virtual address space.
114 *
115 * This structure is used by \p send_callback_request() (executed from handler
116 * context) in order to let the afs process call the specified function. An
117 * instance of that structure is written to a shared memory area together with
118 * the arguments to the callback function. The identifier of the shared memory
119 * area is written to the command socket.
120 *
121 * The afs process accepts connections on the command socket and reads the
122 * shared memory id, attaches the corresponding area, calls the given handler to
123 * perform the desired action and to optionally compute a result.
124 *
125 * The result and a \p callback_result structure is then written to another
126 * shared memory area. The identifier for that area is written to the handler's
127 * command socket, so that the handler process can read the id, attach the
128 * shared memory area and use the result.
129 *
130 * \sa struct callback_result.
131 */
132 struct callback_query {
133 /** The function to be called. */
134 afs_callback *handler;
135 /** The number of bytes of the query */
136 size_t query_size;
137 };
138
139 /**
140 * Structure embedded in the result of a callback.
141 *
142 * If the callback produced a result, an instance of that structure is embedded
143 * into the shared memory area holding the result, mainly to let the command
144 * handler know the size of the result.
145 *
146 * \sa struct callback_query.
147 */
148 struct callback_result {
149 /** The number of bytes of the result. */
150 size_t result_size;
151 /** The band designator (loglevel for the result). */
152 uint8_t band;
153 };
154
155 static int dispatch_result(int result_shmid, callback_result_handler *handler,
156 void *private_result_data)
157 {
158 struct osl_object result;
159 void *result_shm;
160 /* must attach r/w as result.data might get encrypted in-place. */
161 int ret2, ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
162 struct callback_result *cr = result_shm;
163
164 if (ret < 0) {
165 PARA_ERROR_LOG("attach failed: %s\n", para_strerror(-ret));
166 return ret;
167 }
168 result.size = cr->result_size;
169 result.data = result_shm + sizeof(*cr);
170 assert(handler);
171 ret = handler(&result, cr->band, private_result_data);
172 ret2 = shm_detach(result_shm);
173 if (ret2 < 0) {
174 PARA_ERROR_LOG("detach failed: %s\n", para_strerror(-ret2));
175 if (ret >= 0)
176 ret = ret2;
177 }
178 return ret;
179 }
180
181 /**
182 * Ask the afs process to call a given function.
183 *
184 * \param f The function to be called.
185 * \param query Pointer to arbitrary data for the callback.
186 * \param result_handler Called for each shm area sent by the callback.
187 * \param private_result_data Passed verbatim to \a result_handler.
188 *
189 * This function creates a socket for communication with the afs process and a
190 * shared memory area (sma) to which the buffer pointed to by \a query is
191 * copied. It then notifies the afs process that the callback function \a f
192 * should be executed by sending the shared memory identifier (shmid) to the
193 * socket.
194 *
195 * If the callback produces a result, it sends any number of shared memory
196 * identifiers back via the socket. For each such identifier received, \a
197 * result_handler is called. The contents of the sma identified by the received
198 * shmid are passed to that function as an osl object. The private_result_data
199 * pointer is passed as the second argument to \a result_handler.
200 *
201 * \return Number of shared memory areas dispatched on success, negative on errors.
202 *
203 * \sa send_option_arg_callback_request(), send_standard_callback_request().
204 */
205 int send_callback_request(afs_callback *f, struct osl_object *query,
206 callback_result_handler *result_handler,
207 void *private_result_data)
208 {
209 struct callback_query *cq;
210 int ret, fd = -1, query_shmid, result_shmid;
211 void *query_shm;
212 char buf[sizeof(afs_socket_cookie) + sizeof(int)];
213 size_t query_shm_size = sizeof(*cq);
214 int dispatch_error = 0, num_dispatched = 0;
215
216 if (query)
217 query_shm_size += query->size;
218 ret = shm_new(query_shm_size);
219 if (ret < 0)
220 return ret;
221 query_shmid = ret;
222 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
223 if (ret < 0)
224 goto out;
225 cq = query_shm;
226 cq->handler = f;
227 cq->query_size = query_shm_size - sizeof(*cq);
228
229 if (query)
230 memcpy(query_shm + sizeof(*cq), query->data, query->size);
231 ret = shm_detach(query_shm);
232 if (ret < 0)
233 goto out;
234
235 *(uint32_t *)buf = afs_socket_cookie;
236 *(int *)(buf + sizeof(afs_socket_cookie)) = query_shmid;
237
238 ret = connect_local_socket(conf.afs_socket_arg);
239 if (ret < 0)
240 goto out;
241 fd = ret;
242 ret = write_all(fd, buf, sizeof(buf));
243 if (ret < 0)
244 goto out;
245 /*
246 * Read all shmids from afs.
247 *
248 * Even if the dispatcher returns an error we _must_ continue to read
249 * shmids from fd so that we can destroy all shared memory areas that
250 * have been created for us by the afs process.
251 */
252 for (;;) {
253 ret = recv_bin_buffer(fd, buf, sizeof(int));
254 if (ret <= 0)
255 goto out;
256 assert(ret == sizeof(int));
257 ret = *(int *) buf;
258 assert(ret > 0);
259 result_shmid = ret;
260 ret = dispatch_result(result_shmid, result_handler,
261 private_result_data);
262 if (ret < 0 && dispatch_error >= 0)
263 dispatch_error = ret;
264 ret = shm_destroy(result_shmid);
265 if (ret < 0)
266 PARA_CRIT_LOG("destroy result failed: %s\n",
267 para_strerror(-ret));
268 num_dispatched++;
269 }
270 out:
271 if (shm_destroy(query_shmid) < 0)
272 PARA_CRIT_LOG("shm destroy error\n");
273 if (fd >= 0)
274 close(fd);
275 if (dispatch_error < 0)
276 return dispatch_error;
277 if (ret < 0)
278 return ret;
279 return num_dispatched;
280 }
281
282 /**
283 * Send a callback request passing an options structure and an argument vector.
284 *
285 * \param options pointer to an arbitrary data structure.
286 * \param argc Argument count.
287 * \param argv Standard argument vector.
288 * \param f The callback function.
289 * \param result_handler See \ref send_callback_request.
290 * \param private_result_data See \ref send_callback_request.
291 *
292 * Some command handlers pass command-specific options to a callback, together
293 * with a list of further arguments (often a list of audio files). This
294 * function allows to pass an arbitrary structure (given as an osl object) and
295 * a usual argument vector to the specified callback.
296 *
297 * \return The return value of the underlying call to \ref
298 * send_callback_request().
299 *
300 * \sa send_standard_callback_request(), send_callback_request().
301 */
302 int send_option_arg_callback_request(struct osl_object *options,
303 int argc, char * const * const argv, afs_callback *f,
304 callback_result_handler *result_handler,
305 void *private_result_data)
306 {
307 char *p;
308 int i, ret;
309 struct osl_object query = {.size = options? options->size : 0};
310
311 for (i = 0; i < argc; i++)
312 query.size += strlen(argv[i]) + 1;
313 query.data = para_malloc(query.size);
314 p = query.data;
315 if (options) {
316 memcpy(query.data, options->data, options->size);
317 p += options->size;
318 }
319 for (i = 0; i < argc; i++) {
320 strcpy(p, argv[i]); /* OK */
321 p += strlen(argv[i]) + 1;
322 }
323 ret = send_callback_request(f, &query, result_handler,
324 private_result_data);
325 free(query.data);
326 return ret;
327 }
328
329 /**
330 * Send a callback request with an argument vector only.
331 *
332 * \param argc The same meaning as in send_option_arg_callback_request().
333 * \param argv The same meaning as in send_option_arg_callback_request().
334 * \param f The same meaning as in send_option_arg_callback_request().
335 * \param result_handler See \ref send_callback_request.
336 * \param private_result_data See \ref send_callback_request.
337 *
338 * This is similar to send_option_arg_callback_request(), but no options buffer
339 * is passed to the parent process.
340 *
341 * \return The return value of the underlying call to
342 * send_option_arg_callback_request().
343 */
344 int send_standard_callback_request(int argc, char * const * const argv,
345 afs_callback *f, callback_result_handler *result_handler,
346 void *private_result_data)
347 {
348 return send_option_arg_callback_request(NULL, argc, argv, f, result_handler,
349 private_result_data);
350 }
351
352 static int action_if_pattern_matches(struct osl_row *row, void *data)
353 {
354 struct pattern_match_data *pmd = data;
355 struct osl_object name_obj;
356 const char *p, *name;
357 int ret = osl(osl_get_object(pmd->table, row, pmd->match_col_num, &name_obj));
358 const char *pattern_txt = (const char *)pmd->patterns.data;
359
360 if (ret < 0)
361 return ret;
362 name = (char *)name_obj.data;
363 if ((!name || !*name) && (pmd->pm_flags & PM_SKIP_EMPTY_NAME))
364 return 1;
365 if (pmd->patterns.size == 0 &&
366 (pmd->pm_flags & PM_NO_PATTERN_MATCHES_EVERYTHING)) {
367 pmd->num_matches++;
368 return pmd->action(pmd->table, row, name, pmd->data);
369 }
370 for (p = pattern_txt; p < pattern_txt + pmd->patterns.size;
371 p += strlen(p) + 1) {
372 ret = fnmatch(p, name, pmd->fnmatch_flags);
373 if (ret == FNM_NOMATCH)
374 continue;
375 if (ret)
376 return -E_FNMATCH;
377 ret = pmd->action(pmd->table, row, name, pmd->data);
378 if (ret >= 0)
379 pmd->num_matches++;
380 return ret;
381 }
382 return 1;
383 }
384
385 /**
386 * Execute the given function for each matching row.
387 *
388 * \param pmd Describes what to match and how.
389 *
390 * \return Standard.
391 */
392 int for_each_matching_row(struct pattern_match_data *pmd)
393 {
394 if (pmd->pm_flags & PM_REVERSE_LOOP)
395 return osl(osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
396 action_if_pattern_matches));
397 return osl(osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
398 action_if_pattern_matches));
399 }
400
401 /**
402 * Compare two osl objects of string type.
403 *
404 * \param obj1 Pointer to the first object.
405 * \param obj2 Pointer to the second object.
406 *
407 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
408 * are taken into account.
409 *
410 * \return It returns an integer less than, equal to, or greater than zero if
411 * \a obj1 is found, respectively, to be less than, to match, or be greater than
412 * obj2.
413 *
414 * \sa strcmp(3), strncmp(3), osl_compare_func.
415 */
416 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
417 {
418 const char *str1 = (const char *)obj1->data;
419 const char *str2 = (const char *)obj2->data;
420 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
421 }
422
423 static int pass_afd(int fd, char *buf, size_t size)
424 {
425 struct msghdr msg = {.msg_iov = NULL};
426 struct cmsghdr *cmsg;
427 char control[255] __a_aligned(8);
428 int ret;
429 struct iovec iov;
430
431 iov.iov_base = buf;
432 iov.iov_len = size;
433
434 msg.msg_iov = &iov;
435 msg.msg_iovlen = 1;
436
437 msg.msg_control = control;
438 msg.msg_controllen = sizeof(control);
439
440 cmsg = CMSG_FIRSTHDR(&msg);
441 cmsg->cmsg_level = SOL_SOCKET;
442 cmsg->cmsg_type = SCM_RIGHTS;
443 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
444 *(int *)CMSG_DATA(cmsg) = fd;
445
446 /* Sum of the length of all control messages in the buffer */
447 msg.msg_controllen = cmsg->cmsg_len;
448 PARA_DEBUG_LOG("passing %zu bytes and fd %d\n", size, fd);
449 ret = sendmsg(server_socket, &msg, 0);
450 if (ret < 0) {
451 ret = -ERRNO_TO_PARA_ERROR(errno);
452 return ret;
453 }
454 return 1;
455 }
456
457 /**
458 * Pass the fd of the next audio file to the server process.
459 *
460 * This stores all information for streaming the "best" audio file in a shared
461 * memory area. The id of that area and an open file descriptor for the next
462 * audio file are passed to the server process.
463 *
464 * \return Standard.
465 *
466 * \sa open_and_update_audio_file().
467 */
468 static int open_next_audio_file(void)
469 {
470 struct audio_file_data afd;
471 int ret, shmid;
472 char buf[8];
473
474 ret = open_and_update_audio_file(&afd);
475 if (ret < 0) {
476 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
477 goto no_admissible_files;
478 }
479 shmid = ret;
480 if (!write_ok(server_socket)) {
481 ret = -E_AFS_SOCKET;
482 goto destroy;
483 }
484 *(uint32_t *)buf = NEXT_AUDIO_FILE;
485 *(uint32_t *)(buf + 4) = (uint32_t)shmid;
486 ret = pass_afd(afd.fd, buf, 8);
487 close(afd.fd);
488 if (ret >= 0)
489 return ret;
490 destroy:
491 shm_destroy(shmid);
492 return ret;
493 no_admissible_files:
494 *(uint32_t *)buf = NO_ADMISSIBLE_FILES;
495 *(uint32_t *)(buf + 4) = (uint32_t)0;
496 return write_all(server_socket, buf, 8);
497 }
498
499 /* Never fails if arg == NULL */
500 static int activate_mood_or_playlist(const char *arg, int *num_admissible)
501 {
502 enum play_mode mode;
503 int ret;
504
505 if (!arg) {
506 ret = change_current_mood(NULL); /* always successful */
507 mode = PLAY_MODE_MOOD;
508 } else {
509 if (!strncmp(arg, "p/", 2)) {
510 ret = playlist_open(arg + 2);
511 mode = PLAY_MODE_PLAYLIST;
512 } else if (!strncmp(arg, "m/", 2)) {
513 ret = change_current_mood(arg + 2);
514 mode = PLAY_MODE_MOOD;
515 } else
516 return -E_AFS_SYNTAX;
517 if (ret < 0)
518 return ret;
519 }
520 if (num_admissible)
521 *num_admissible = ret;
522 current_play_mode = mode;
523 if (arg != current_mop) {
524 free(current_mop);
525 if (arg) {
526 current_mop = para_strdup(arg);
527 mutex_lock(mmd_mutex);
528 strncpy(mmd->afs_mode_string, arg,
529 sizeof(mmd->afs_mode_string));
530 mmd->afs_mode_string[sizeof(mmd->afs_mode_string) - 1] = '\0';
531 mutex_unlock(mmd_mutex);
532 } else {
533 mutex_lock(mmd_mutex);
534 strcpy(mmd->afs_mode_string, "dummy");
535 mutex_unlock(mmd_mutex);
536 current_mop = NULL;
537 }
538 }
539 return 1;
540 }
541
542 /**
543 * Result handler for sending data to the para_client process.
544 *
545 * \param result The data to be sent.
546 * \param band The band designator.
547 * \param private Pointer to the command context.
548 *
549 * \return The return value of the underlying call to \ref command.c::send_sb.
550 *
551 * \sa \ref callback_result_handler, \ref command.c::send_sb.
552 */
553 int afs_cb_result_handler(struct osl_object *result, uint8_t band,
554 void *private)
555 {
556 struct command_context *cc = private;
557
558 assert(cc);
559 switch (band) {
560 case SBD_OUTPUT:
561 case SBD_DEBUG_LOG:
562 case SBD_INFO_LOG:
563 case SBD_NOTICE_LOG:
564 case SBD_WARNING_LOG:
565 case SBD_ERROR_LOG:
566 case SBD_CRIT_LOG:
567 case SBD_EMERG_LOG:
568 assert(result->size > 0);
569 return send_sb(&cc->scc, result->data, result->size, band, true);
570 case SBD_AFS_CB_FAILURE:
571 return *(int *)(result->data);
572 default:
573 return -E_BAD_BAND;
574 }
575 }
576
577 static void flush_and_free_pb(struct para_buffer *pb)
578 {
579 int ret;
580 struct afs_max_size_handler_data *amshd = pb->private_data;
581
582 if (pb->buf && pb->size > 0) {
583 ret = pass_buffer_as_shm(amshd->fd, amshd->band, pb->buf,
584 pb->offset);
585 if (ret < 0)
586 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
587 }
588 free(pb->buf);
589 }
590
591 static int com_select_callback(struct afs_callback_arg *aca)
592 {
593 const char *arg = aca->query.data;
594 int num_admissible, ret;
595
596 ret = clear_score_table();
597 if (ret < 0) {
598 para_printf(&aca->pbout, "could not clear score table: %s\n",
599 para_strerror(-ret));
600 return ret;
601 }
602 if (current_play_mode == PLAY_MODE_MOOD)
603 close_current_mood();
604 else
605 playlist_close();
606 ret = activate_mood_or_playlist(arg, &num_admissible);
607 if (ret >= 0)
608 goto out;
609 /* ignore subsequent errors (but log them) */
610 para_printf(&aca->pbout, "could not activate %s\n", arg);
611 if (current_mop) {
612 int ret2;
613 para_printf(&aca->pbout, "switching back to %s\n", current_mop);
614 ret2 = activate_mood_or_playlist(current_mop, &num_admissible);
615 if (ret2 >= 0)
616 goto out;
617 para_printf(&aca->pbout, "could not reactivate %s: %s\n",
618 current_mop, para_strerror(-ret2));
619 }
620 para_printf(&aca->pbout, "activating dummy mood\n");
621 activate_mood_or_playlist(NULL, &num_admissible);
622 out:
623 para_printf(&aca->pbout, "activated %s (%d admissible files)\n",
624 current_mop? current_mop : "dummy mood", num_admissible);
625 return ret;
626 }
627
628 int com_select(struct command_context *cc)
629 {
630 struct osl_object query;
631
632 if (cc->argc != 2)
633 return -E_AFS_SYNTAX;
634 query.data = cc->argv[1];
635 query.size = strlen(cc->argv[1]) + 1;
636 return send_callback_request(com_select_callback, &query,
637 &afs_cb_result_handler, cc);
638 }
639
640 static void init_admissible_files(char *arg)
641 {
642 if (activate_mood_or_playlist(arg, NULL) < 0)
643 activate_mood_or_playlist(NULL, NULL); /* always successful */
644 }
645
646 static int setup_command_socket_or_die(void)
647 {
648 int ret, socket_fd;
649 char *socket_name = conf.afs_socket_arg;
650
651 unlink(socket_name);
652 ret = create_local_socket(socket_name);
653 if (ret < 0) {
654 PARA_EMERG_LOG("%s: %s\n", para_strerror(-ret), socket_name);
655 exit(EXIT_FAILURE);
656 }
657 socket_fd = ret;
658 PARA_INFO_LOG("listening on socket %s (fd %d)\n", socket_name,
659 socket_fd);
660 return socket_fd;
661 }
662
663 static void close_afs_tables(void)
664 {
665 int i;
666 PARA_NOTICE_LOG("closing afs_tables\n");
667 for (i = 0; i < NUM_AFS_TABLES; i++)
668 afs_tables[i].close();
669 }
670
671 static char *database_dir;
672
673 static void get_database_dir(void)
674 {
675 if (!database_dir) {
676 if (conf.afs_database_dir_given)
677 database_dir = para_strdup(conf.afs_database_dir_arg);
678 else {
679 char *home = para_homedir();
680 database_dir = make_message(
681 "%s/.paraslash/afs_database-0.4", home);
682 free(home);
683 }
684 }
685 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
686 }
687
688 static int make_database_dir(void)
689 {
690 int ret;
691
692 get_database_dir();
693 ret = para_mkdir(database_dir, 0777);
694 if (ret >= 0 || ret == -ERRNO_TO_PARA_ERROR(EEXIST))
695 return 1;
696 return ret;
697 }
698
699 static int open_afs_tables(void)
700 {
701 int i, ret;
702
703 get_database_dir();
704 PARA_NOTICE_LOG("opening %d osl tables in %s\n", NUM_AFS_TABLES,
705 database_dir);
706 for (i = 0; i < NUM_AFS_TABLES; i++) {
707 ret = afs_tables[i].open(database_dir);
708 if (ret >= 0)
709 continue;
710 PARA_ERROR_LOG("%s init: %s\n", afs_tables[i].name,
711 para_strerror(-ret));
712 break;
713 }
714 if (ret >= 0)
715 return ret;
716 while (i)
717 afs_tables[--i].close();
718 return ret;
719 }
720
721 static int afs_signal_post_select(struct sched *s, __a_unused void *context)
722 {
723 int signum, ret;
724
725 if (getppid() == 1) {
726 PARA_EMERG_LOG("para_server died\n");
727 goto shutdown;
728 }
729 signum = para_next_signal(&s->rfds);
730 if (signum == 0)
731 return 0;
732 if (signum == SIGHUP) {
733 close_afs_tables();
734 parse_config_or_die(1);
735 ret = open_afs_tables();
736 if (ret < 0)
737 return ret;
738 init_admissible_files(current_mop);
739 return 0;
740 }
741 PARA_EMERG_LOG("terminating on signal %d\n", signum);
742 shutdown:
743 task_notify_all(s, E_AFS_SIGNAL);
744 return -E_AFS_SIGNAL;
745 }
746
747 static void register_signal_task(struct sched *s)
748 {
749 para_sigaction(SIGPIPE, SIG_IGN);
750 signal_task = signal_init_or_die();
751 para_install_sighandler(SIGINT);
752 para_install_sighandler(SIGTERM);
753 para_install_sighandler(SIGHUP);
754
755 signal_task->task = task_register(&(struct task_info) {
756 .name = "signal",
757 .pre_select = signal_pre_select,
758 .post_select = afs_signal_post_select,
759 .context = signal_task,
760
761 }, s);
762 }
763
764 static struct list_head afs_client_list;
765
766 /** Describes one connected afs client. */
767 struct afs_client {
768 /** Position in the afs client list. */
769 struct list_head node;
770 /** The socket file descriptor for this client. */
771 int fd;
772 /** The time the client connected. */
773 struct timeval connect_time;
774 };
775
776 static void command_pre_select(struct sched *s, void *context)
777 {
778 struct command_task *ct = context;
779 struct afs_client *client;
780
781 para_fd_set(server_socket, &s->rfds, &s->max_fileno);
782 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
783 list_for_each_entry(client, &afs_client_list, node)
784 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
785 }
786
787 /**
788 * Send data as shared memory to a file descriptor.
789 *
790 * \param fd File descriptor to send the shmid to.
791 * \param band The band designator for this data.
792 * \param buf The buffer holding the data to be sent.
793 * \param size The size of \a buf.
794 *
795 * This function creates a shared memory area large enough to hold
796 * the content given by \a buf and \a size and sends the identifier
797 * of this area to the file descriptor \a fd.
798 *
799 * It is called by the AFS max_size handler as well as directly by the AFS
800 * command callbacks to send command output to the command handlers.
801 *
802 * \return Zero if \a buf is \p NULL or \a size is zero. Negative on errors,
803 * and positive on success.
804 */
805 int pass_buffer_as_shm(int fd, uint8_t band, const char *buf, size_t size)
806 {
807 int ret, shmid;
808 void *shm;
809 struct callback_result *cr;
810
811 if (size == 0)
812 assert(band != SBD_OUTPUT);
813 ret = shm_new(size + sizeof(*cr));
814 if (ret < 0)
815 return ret;
816 shmid = ret;
817 ret = shm_attach(shmid, ATTACH_RW, &shm);
818 if (ret < 0)
819 goto err;
820 cr = shm;
821 cr->result_size = size;
822 cr->band = band;
823 if (size > 0)
824 memcpy(shm + sizeof(*cr), buf, size);
825 ret = shm_detach(shm);
826 if (ret < 0)
827 goto err;
828 ret = write_all(fd, (char *)&shmid, sizeof(int));
829 if (ret >= 0)
830 return ret;
831 err:
832 if (shm_destroy(shmid) < 0)
833 PARA_ERROR_LOG("destroy result failed\n");
834 return ret;
835 }
836
837 static int call_callback(int fd, int query_shmid)
838 {
839 void *query_shm;
840 struct callback_query *cq;
841 int ret, ret2;
842 struct afs_callback_arg aca = {.fd = fd};
843
844 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
845 if (ret < 0)
846 return ret;
847 cq = query_shm;
848 aca.query.data = (char *)query_shm + sizeof(*cq);
849 aca.query.size = cq->query_size;
850 aca.pbout.max_size = shm_get_shmmax();
851 aca.pbout.max_size_handler = afs_max_size_handler;
852 aca.pbout.private_data = &(struct afs_max_size_handler_data) {
853 .fd = fd,
854 .band = SBD_OUTPUT
855 };
856 ret = cq->handler(&aca);
857 ret2 = shm_detach(query_shm);
858 if (ret2 < 0) {
859 if (ret < 0) /* ignore (but log) detach error */
860 PARA_ERROR_LOG("could not detach sma: %s\n",
861 para_strerror(-ret2));
862 else
863 ret = ret2;
864 }
865 flush_and_free_pb(&aca.pbout);
866 if (ret < 0) {
867 ret2 = pass_buffer_as_shm(fd, SBD_AFS_CB_FAILURE,
868 (const char *)&ret, sizeof(ret));
869 if (ret2 < 0)
870 PARA_ERROR_LOG("could not pass cb failure packet: %s\n",
871 para_strerror(-ret));
872 }
873 return ret;
874 }
875
876 static int execute_server_command(fd_set *rfds)
877 {
878 char buf[8];
879 size_t n;
880 int ret = read_nonblock(server_socket, buf, sizeof(buf) - 1, rfds, &n);
881
882 if (ret < 0 || n == 0)
883 return ret;
884 buf[n] = '\0';
885 if (strcmp(buf, "new"))
886 return -E_BAD_CMD;
887 return open_next_audio_file();
888 }
889
890 /* returns 0 if no data available, 1 else */
891 static int execute_afs_command(int fd, fd_set *rfds, uint32_t expected_cookie)
892 {
893 uint32_t cookie;
894 int query_shmid;
895 char buf[sizeof(cookie) + sizeof(query_shmid)];
896 size_t n;
897 int ret = read_nonblock(fd, buf, sizeof(buf), rfds, &n);
898
899 if (ret < 0)
900 goto err;
901 if (n == 0)
902 return 0;
903 if (n != sizeof(buf)) {
904 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
905 ret, (long unsigned) sizeof(buf));
906 return 1;
907 }
908 cookie = *(uint32_t *)buf;
909 if (cookie != expected_cookie) {
910 PARA_NOTICE_LOG("received invalid cookie (got %u, expected %u)\n",
911 (unsigned)cookie, (unsigned)expected_cookie);
912 return 1;
913 }
914 query_shmid = *(int *)(buf + sizeof(cookie));
915 if (query_shmid < 0) {
916 PARA_WARNING_LOG("received invalid query shmid %d)\n",
917 query_shmid);
918 return 1;
919 }
920 ret = call_callback(fd, query_shmid);
921 if (ret >= 0)
922 return 1;
923 err:
924 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
925 return 1;
926 }
927
928 /** Shutdown connection if query has not arrived until this many seconds. */
929 #define AFS_CLIENT_TIMEOUT 3
930
931 static int command_post_select(struct sched *s, void *context)
932 {
933 struct command_task *ct = context;
934 struct sockaddr_un unix_addr;
935 struct afs_client *client, *tmp;
936 int fd, ret;
937
938 ret = task_get_notification(ct->task);
939 if (ret < 0)
940 return ret;
941 ret = execute_server_command(&s->rfds);
942 if (ret < 0) {
943 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
944 task_notify_all(s, -ret);
945 return ret;
946 }
947 /* Check the list of connected clients. */
948 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
949 ret = execute_afs_command(client->fd, &s->rfds, ct->cookie);
950 if (ret == 0) { /* prevent bogus connection flooding */
951 struct timeval diff;
952 tv_diff(now, &client->connect_time, &diff);
953 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
954 continue;
955 PARA_WARNING_LOG("connection timeout\n");
956 }
957 close(client->fd);
958 list_del(&client->node);
959 free(client);
960 }
961 /* Accept connections on the local socket. */
962 ret = para_accept(ct->fd, &s->rfds, &unix_addr, sizeof(unix_addr), &fd);
963 if (ret < 0)
964 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
965 if (ret <= 0)
966 return 0;
967 ret = mark_fd_nonblocking(fd);
968 if (ret < 0) {
969 PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
970 close(fd);
971 return 0;
972 }
973 client = para_malloc(sizeof(*client));
974 client->fd = fd;
975 client->connect_time = *now;
976 para_list_add(&client->node, &afs_client_list);
977 return 0;
978 }
979
980 static void register_command_task(uint32_t cookie, struct sched *s)
981 {
982 struct command_task *ct = &command_task_struct;
983 ct->fd = setup_command_socket_or_die();
984 ct->cookie = cookie;
985
986 ct->task = task_register(&(struct task_info) {
987 .name = "afs command",
988 .pre_select = command_pre_select,
989 .post_select = command_post_select,
990 .context = ct,
991 }, s);
992 }
993
994 /**
995 * Initialize the audio file selector process.
996 *
997 * \param cookie The value used for "authentication".
998 * \param socket_fd File descriptor used for communication with the server.
999 */
1000 __noreturn void afs_init(uint32_t cookie, int socket_fd)
1001 {
1002 static struct sched s;
1003 int i, ret;
1004
1005 register_signal_task(&s);
1006 INIT_LIST_HEAD(&afs_client_list);
1007 for (i = 0; i < NUM_AFS_TABLES; i++)
1008 afs_tables[i].init(&afs_tables[i]);
1009 ret = open_afs_tables();
1010 if (ret < 0)
1011 goto out;
1012 server_socket = socket_fd;
1013 ret = mark_fd_nonblocking(server_socket);
1014 if (ret < 0)
1015 goto out_close;
1016 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
1017 server_socket, (unsigned) cookie);
1018 init_admissible_files(conf.afs_initial_mode_arg);
1019 register_command_task(cookie, &s);
1020 s.default_timeout.tv_sec = 0;
1021 s.default_timeout.tv_usec = 999 * 1000;
1022 ret = write(socket_fd, "\0", 1);
1023 if (ret != 1) {
1024 if (ret == 0)
1025 errno = EINVAL;
1026 ret = -ERRNO_TO_PARA_ERROR(errno);
1027 goto out_close;
1028 }
1029 ret = schedule(&s);
1030 sched_shutdown(&s);
1031 out_close:
1032 close_afs_tables();
1033 out:
1034 if (ret < 0)
1035 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1036 exit(EXIT_FAILURE);
1037 }
1038
1039 static int com_init_callback(struct afs_callback_arg *aca)
1040 {
1041 uint32_t table_mask = *(uint32_t *)aca->query.data;
1042 int i, ret;
1043
1044 close_afs_tables();
1045 for (i = 0; i < NUM_AFS_TABLES; i++) {
1046 struct afs_table *t = &afs_tables[i];
1047
1048 if (!(table_mask & (1 << i)))
1049 continue;
1050 if (!t->create)
1051 continue;
1052 ret = t->create(database_dir);
1053 if (ret < 0) {
1054 para_printf(&aca->pbout, "cannot create table %s\n",
1055 t->name);
1056 goto out;
1057 }
1058 para_printf(&aca->pbout, "successfully created %s table\n",
1059 t->name);
1060 }
1061 ret = open_afs_tables();
1062 if (ret < 0)
1063 para_printf(&aca->pbout, "cannot open afs tables\n");
1064 out:
1065 return ret;
1066 }
1067
1068 int com_init(struct command_context *cc)
1069 {
1070 int i, j, ret;
1071 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
1072 struct osl_object query = {.data = &table_mask,
1073 .size = sizeof(table_mask)};
1074
1075 ret = make_database_dir();
1076 if (ret < 0)
1077 return ret;
1078 if (cc->argc != 1) {
1079 table_mask = 0;
1080 for (i = 1; i < cc->argc; i++) {
1081 for (j = 0; j < NUM_AFS_TABLES; j++) {
1082 struct afs_table *t = &afs_tables[j];
1083
1084 if (strcmp(cc->argv[i], t->name))
1085 continue;
1086 table_mask |= (1 << j);
1087 break;
1088 }
1089 if (j == NUM_AFS_TABLES)
1090 return -E_BAD_TABLE_NAME;
1091 }
1092 }
1093 return send_callback_request(com_init_callback, &query,
1094 afs_cb_result_handler, cc);
1095 }
1096
1097 /**
1098 * Flags for the check command.
1099 *
1100 * \sa com_check().
1101 */
1102 enum com_check_flags {
1103 /** Check the audio file table. */
1104 CHECK_AFT = 1,
1105 /** Check the mood table. */
1106 CHECK_MOODS = 2,
1107 /** Check the playlist table. */
1108 CHECK_PLAYLISTS = 4,
1109 /** Check the attribute table against the audio file table. */
1110 CHECK_ATTS = 8
1111 };
1112
1113 int com_check(struct command_context *cc)
1114 {
1115 unsigned flags = 0;
1116 int i, ret;
1117
1118 for (i = 1; i < cc->argc; i++) {
1119 const char *arg = cc->argv[i];
1120 if (arg[0] != '-')
1121 break;
1122 if (!strcmp(arg, "--")) {
1123 i++;
1124 break;
1125 }
1126 if (!strcmp(arg, "-a")) {
1127 flags |= CHECK_AFT;
1128 continue;
1129 }
1130 if (!strcmp(arg, "-A")) {
1131 flags |= CHECK_ATTS;
1132 continue;
1133 }
1134 if (!strcmp(arg, "-p")) {
1135 flags |= CHECK_PLAYLISTS;
1136 continue;
1137 }
1138 if (!strcmp(arg, "-m")) {
1139 flags |= CHECK_MOODS;
1140 continue;
1141 }
1142 return -E_AFS_SYNTAX;
1143 }
1144 if (i < cc->argc)
1145 return -E_AFS_SYNTAX;
1146 if (!flags)
1147 flags = ~0U;
1148 if (flags & CHECK_AFT) {
1149 ret = send_callback_request(aft_check_callback, NULL,
1150 afs_cb_result_handler, cc);
1151 if (ret < 0)
1152 return ret;
1153 }
1154 if (flags & CHECK_ATTS) {
1155 ret = send_callback_request(attribute_check_callback, NULL,
1156 afs_cb_result_handler, cc);
1157 if (ret < 0)
1158 return ret;
1159 }
1160 if (flags & CHECK_PLAYLISTS) {
1161 ret = send_callback_request(playlist_check_callback,
1162 NULL, afs_cb_result_handler, cc);
1163 if (ret < 0)
1164 return ret;
1165 }
1166 if (flags & CHECK_MOODS) {
1167 ret = send_callback_request(mood_check_callback, NULL,
1168 afs_cb_result_handler, cc);
1169 if (ret < 0)
1170 return ret;
1171 }
1172 return 1;
1173 }
1174
1175 /**
1176 * The afs event dispatcher.
1177 *
1178 * \param event Type of the event.
1179 * \param pb May be \p NULL.
1180 * \param data Type depends on \a event.
1181 *
1182 * This function calls each table event handler, passing \a pb and \a data
1183 * verbatim. It's up to the handlers to interpret the \a data pointer. If a
1184 * handler returns negative, the loop is aborted.
1185 *
1186 * \return The (negative) error code of the first handler that failed, or non-negative
1187 * if all handlers succeeded.
1188 */
1189 __must_check int afs_event(enum afs_events event, struct para_buffer *pb,
1190 void *data)
1191 {
1192 int i, ret;
1193
1194 for (i = 0; i < NUM_AFS_TABLES; i++) {
1195 struct afs_table *t = &afs_tables[i];
1196 if (!t->event_handler)
1197 continue;
1198 ret = t->event_handler(event, pb, data);
1199 if (ret < 0) {
1200 PARA_CRIT_LOG("table %s, event %u: %s\n", t->name,
1201 event, para_strerror(-ret));
1202 return ret;
1203 }
1204 }
1205 return 1;
1206 }
1207
1208 /**
1209 * Dummy event handler for the images table.
1210 *
1211 * \param event Unused.
1212 * \param pb Unused.
1213 * \param data Unused.
1214 *
1215 * \return The images table does not honor events, so this handler always
1216 * returns success.
1217 */
1218 __a_const int images_event_handler(__a_unused enum afs_events event,
1219 __a_unused struct para_buffer *pb, __a_unused void *data)
1220 {
1221 return 1;
1222 }
1223
1224 /**
1225 * Dummy event handler for the lyrics table.
1226 *
1227 * \param event Unused.
1228 * \param pb Unused.
1229 * \param data Unused.
1230 *
1231 * \return The lyrics table does not honor events, so this handler always
1232 * returns success.
1233 */
1234 __a_const int lyrics_event_handler(__a_unused enum afs_events event,
1235 __a_unused struct para_buffer *pb, __a_unused void *data)
1236 {
1237 return 1;
1238 }