loglevel adjustments.
[paraslash.git] / afs.c
1 /*
2 * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
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 <signal.h>
10 #include <fnmatch.h>
11 #include "server.cmdline.h"
12 #include "para.h"
13 #include "error.h"
14 #include "string.h"
15 #include "afh.h"
16 #include "afs.h"
17 #include "server.h"
18 #include <dirent.h> /* readdir() */
19 #include <sys/mman.h>
20 #include <sys/time.h>
21 #include "net.h"
22 #include "ipc.h"
23 #include "list.h"
24 #include "sched.h"
25 #include "signal.h"
26 #include "fd.h"
27
28 /** The osl tables used by afs. \sa blob.c. */
29 enum afs_table_num {
30 /** Contains audio file information. See aft.c. */
31 TBLNUM_AUDIO_FILES,
32 /** The table for the paraslash attributes. See attribute.c. */
33 TBLNUM_ATTRIBUTES,
34 /**
35 * Paraslash's scoring system is based on Gaussian normal
36 * distributions, and the relevant data is stored in the rbtrees of an
37 * osl table containing only volatile columns. See score.c for
38 * details.
39 */
40 TBLNUM_SCORES,
41 /**
42 * A standard blob table containing the mood definitions. For details
43 * see mood.c.
44 */
45 TBLNUM_MOODS,
46 /** A blob table containing lyrics on a per-song basis. */
47 TBLNUM_LYRICS,
48 /** Another blob table for images (for example album cover art). */
49 TBLNUM_IMAGES,
50 /** Yet another blob table for storing standard playlists. */
51 TBLNUM_PLAYLIST,
52 /** How many tables are in use? */
53 NUM_AFS_TABLES
54 };
55
56 static struct afs_table afs_tables[NUM_AFS_TABLES] = {
57 [TBLNUM_AUDIO_FILES] = {.init = aft_init},
58 [TBLNUM_ATTRIBUTES] = {.init = attribute_init},
59 [TBLNUM_SCORES] = {.init = score_init},
60 [TBLNUM_MOODS] = {.init = moods_init},
61 [TBLNUM_LYRICS] = {.init = lyrics_init},
62 [TBLNUM_IMAGES] = {.init = images_init},
63 [TBLNUM_PLAYLIST] = {.init = playlists_init},
64 };
65
66 struct command_task {
67 /** The file descriptor for the local socket. */
68 int fd;
69 /**
70 * Value sent by the command handlers to identify themselves as
71 * children of the running para_server.
72 */
73 uint32_t cookie;
74 /** The associated task structure. */
75 struct task task;
76 };
77
78 extern struct misc_meta_data *mmd;
79
80 static int server_socket;
81 static struct command_task command_task_struct;
82 static struct signal_task signal_task_struct;
83
84 static enum play_mode current_play_mode;
85 static char *current_mop; /* mode or playlist specifier. NULL means dummy mooe */
86
87
88 /**
89 * A random number used to "authenticate" the connection.
90 *
91 * para_server picks this number by random before forking the afs process. The
92 * command handlers write this number together with the id of the shared memory
93 * area containing the query. This way, a malicious local user has to know this
94 * number to be able to cause the afs process to crash by sending fake queries.
95 */
96 extern uint32_t afs_socket_cookie;
97
98 /**
99 * Struct to let command handlers execute a callback in afs context.
100 *
101 * Commands that need to change the state of afs can't change the relevant data
102 * structures directly because commands are executed in a child process, i.e.
103 * they get their own virtual address space.
104 *
105 * This structure is used by \p send_callback_request() (executed from handler
106 * context) in order to let the afs process call the specified function. An
107 * instance of that structure is written to a shared memory area together with
108 * the arguments to the callback function. The identifier of the shared memory
109 * area is written to the command socket.
110 *
111 * The afs process accepts connections on the command socket and reads the
112 * shared memory id, attaches the corresponing area, calls the given handler to
113 * perform the desired action and to optionally compute a result.
114 *
115 * The result and a \p callback_result structure is then written to another
116 * shared memory area. The identifier for that area is written to the handler's
117 * command socket, so that the handler process can read the id, attach the
118 * shared memory area and use the result.
119 *
120 * \sa struct callback_result.
121 */
122 struct callback_query {
123 /** The function to be called. */
124 callback_function *handler;
125 /** The number of bytes of the query */
126 size_t query_size;
127 };
128
129 /**
130 * Structure embedded in the result of a callback.
131 *
132 * If the callback produced a result, an instance of that structure is embeeded
133 * into the shared memory area holding the result, mainly to let the command
134 * handler know the size of the result.
135 *
136 * \sa struct callback_query.
137 */
138 struct callback_result {
139 /** The number of bytes of the result. */
140 size_t result_size;
141 };
142
143 /**
144 * Ask the afs process to call a given function.
145 *
146 * \param f The function to be called.
147 * \param query Pointer to arbitrary data for the callback.
148 * \param result Callback result will be stored here.
149 *
150 * This function creates a shared memory area, copies the buffer pointed to by
151 * query to that area and notifies the afs process that \a f should be
152 * called ASAP.
153 *
154 * \return Negative, on errors, the return value of the callback function
155 * otherwise.
156 *
157 * \sa send_option_arg_callback_request(), send_standard_callback_request().
158 */
159 int send_callback_request(callback_function *f, struct osl_object *query,
160 struct osl_object *result)
161 {
162 struct callback_query *cq;
163 struct callback_result *cr;
164 int ret, fd = -1, query_shmid, result_shmid;
165 void *query_shm, *result_shm;
166 char buf[sizeof(afs_socket_cookie) + sizeof(int)];
167 struct sockaddr_un unix_addr;
168 size_t query_shm_size = sizeof(*cq);
169
170 if (query)
171 query_shm_size += query->size;
172 ret = shm_new(query_shm_size);
173 if (ret < 0)
174 return ret;
175 query_shmid = ret;
176 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
177 if (ret < 0)
178 goto out;
179 cq = query_shm;
180 cq->handler = f;
181 cq->query_size = query_shm_size - sizeof(*cq);
182
183 if (query)
184 memcpy(query_shm + sizeof(*cq), query->data, query->size);
185 ret = shm_detach(query_shm);
186 if (ret < 0)
187 goto out;
188
189 *(uint32_t *) buf = afs_socket_cookie;
190 *(int *) (buf + sizeof(afs_socket_cookie)) = query_shmid;
191
192 ret = get_stream_socket(PF_UNIX);
193 if (ret < 0)
194 goto out;
195 fd = ret;
196 ret = init_unix_addr(&unix_addr, conf.afs_socket_arg);
197 if (ret < 0)
198 goto out;
199 ret = PARA_CONNECT(fd, &unix_addr);
200 if (ret < 0)
201 goto out;
202 ret = send_bin_buffer(fd, buf, sizeof(buf));
203 if (ret < 0)
204 goto out;
205 ret = recv_bin_buffer(fd, buf, sizeof(buf));
206 if (ret < 0)
207 goto out;
208 if (ret != sizeof(int)) {
209 ret = -E_RECV;
210 goto out;
211 }
212 ret = *(int *) buf;
213 if (ret <= 0)
214 goto out;
215 result_shmid = ret;
216 ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
217 if (ret >= 0) {
218 assert(result);
219 cr = result_shm;
220 result->size = cr->result_size;
221 result->data = para_malloc(result->size);
222 memcpy(result->data, result_shm + sizeof(*cr), result->size);
223 ret = shm_detach(result_shm);
224 if (ret < 0)
225 PARA_ERROR_LOG("can not detach result\n");
226 } else
227 PARA_ERROR_LOG("attach result failed: %d\n", ret);
228 if (shm_destroy(result_shmid) < 0)
229 PARA_ERROR_LOG("destroy result failed\n");
230 ret = 1;
231 out:
232 if (shm_destroy(query_shmid) < 0)
233 PARA_ERROR_LOG("%s\n", "shm destroy error");
234 if (fd >= 0)
235 close(fd);
236 // PARA_DEBUG_LOG("callback_ret: %d\n", ret);
237 return ret;
238 }
239
240 /**
241 * Send a callback request passing an options structure and an argument vector.
242 *
243 * \param options pointer to an arbitrary data structure.
244 * \param argc Argument count.
245 * \param argv Standard argument vector.
246 * \param f The callback function.
247 * \param result The result of the query is stored here.
248 *
249 * Some commands have a couple of options that are parsed in child context for
250 * syntactic correctness and are stored in a special options structure for that
251 * command. This function allows to pass such a structure together with a list
252 * of further arguments (often a list of audio files) to the parent process.
253 *
254 * \sa send_standard_callback_request(), send_callback_request().
255 */
256 int send_option_arg_callback_request(struct osl_object *options,
257 int argc, char * const * const argv, callback_function *f,
258 struct osl_object *result)
259 {
260 char *p;
261 int i, ret;
262 struct osl_object query = {.size = options? options->size : 0};
263
264 for (i = 0; i < argc; i++)
265 query.size += strlen(argv[i]) + 1;
266 query.data = para_malloc(query.size);
267 p = query.data;
268 if (options) {
269 memcpy(query.data, options->data, options->size);
270 p += options->size;
271 }
272 for (i = 0; i < argc; i++) {
273 strcpy(p, argv[i]); /* OK */
274 p += strlen(argv[i]) + 1;
275 }
276 ret = send_callback_request(f, &query, result);
277 free(query.data);
278 return ret;
279 }
280
281 /**
282 * Send a callback request with an argument vector only.
283 *
284 * \param argc The same meaning as in send_option_arg_callback_request().
285 * \param argv The same meaning as in send_option_arg_callback_request().
286 * \param f The same meaning as in send_option_arg_callback_request().
287 * \param result The same meaning as in send_option_arg_callback_request().
288 *
289 * This is similar to send_option_arg_callback_request(), but no options buffer
290 * is passed to the parent process.
291 *
292 * \return The return value of the underlying call to
293 * send_option_arg_callback_request().
294 */
295 int send_standard_callback_request(int argc, char * const * const argv,
296 callback_function *f, struct osl_object *result)
297 {
298 return send_option_arg_callback_request(NULL, argc, argv, f, result);
299 }
300
301 static int action_if_pattern_matches(struct osl_row *row, void *data)
302 {
303 struct pattern_match_data *pmd = data;
304 struct osl_object name_obj;
305 const char *p, *name;
306 int ret = osl_get_object(pmd->table, row, pmd->match_col_num, &name_obj);
307 const char *pattern_txt = (const char *)pmd->patterns.data;
308
309 if (ret < 0)
310 return ret;
311 name = (char *)name_obj.data;
312 if ((!name || !*name) && (pmd->pm_flags & PM_SKIP_EMPTY_NAME))
313 return 1;
314 if (!pmd->patterns.size && (pmd->pm_flags & PM_NO_PATTERN_MATCHES_EVERYTHING))
315 return pmd->action(pmd->table, row, name, pmd->data);
316 for (p = pattern_txt; p < pattern_txt + pmd->patterns.size;
317 p += strlen(p) + 1) {
318 ret = fnmatch(p, name, pmd->fnmatch_flags);
319 if (ret == FNM_NOMATCH)
320 continue;
321 if (ret)
322 return -E_FNMATCH;
323 return pmd->action(pmd->table, row, name, pmd->data);
324 }
325 return 1;
326 }
327
328 /**
329 * Execute the given function for each matching row.
330 *
331 * \param pmd Describes what to match and how.
332 *
333 * \return The return value of the underlying call to osl_rbtree_loop()
334 * or osl_rbtree_loop_reverse().
335 */
336 int for_each_matching_row(struct pattern_match_data *pmd)
337 {
338 if (pmd->pm_flags & PM_REVERSE_LOOP)
339 return osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
340 action_if_pattern_matches);
341 return osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
342 action_if_pattern_matches);
343 }
344
345 /**
346 * Compare two osl objects of string type.
347 *
348 * \param obj1 Pointer to the first object.
349 * \param obj2 Pointer to the second object.
350 *
351 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
352 * are taken into account.
353 *
354 * \return It returns an integer less than, equal to, or greater than zero if
355 * \a obj1 is found, respectively, to be less than, to match, or be greater than
356 * obj2.
357 *
358 * \sa strcmp(3), strncmp(3), osl_compare_func.
359 */
360 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
361 {
362 const char *str1 = (const char *)obj1->data;
363 const char *str2 = (const char *)obj2->data;
364 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
365 }
366
367 /*
368 * write input from fd to dynamically allocated buffer,
369 * but maximal max_size byte.
370 */
371 static int fd2buf(int fd, unsigned max_size, struct osl_object *obj)
372 {
373 const size_t chunk_size = 1024;
374 size_t size = 2048, received = 0;
375 int ret;
376 char *buf = para_malloc(size);
377
378 for (;;) {
379 ret = recv_bin_buffer(fd, buf + received, chunk_size);
380 if (ret <= 0)
381 break;
382 received += ret;
383 if (received + chunk_size >= size) {
384 size *= 2;
385 ret = -E_INPUT_TOO_LARGE;
386 if (size > max_size)
387 break;
388 buf = para_realloc(buf, size);
389 }
390 }
391 obj->data = buf;
392 obj->size = received;
393 if (ret < 0)
394 free(buf);
395 return ret;
396 }
397
398 /**
399 * Read data from a file descriptor, and send it to the afs process.
400 *
401 * \param fd File descriptor to read data from.
402 * \param arg_obj Pointer to the arguments to \a f.
403 * \param f The callback function.
404 * \param max_len Don't read more than that many bytes from stdin.
405 * \param result The result of the query is stored here.
406 *
407 * This function is used by commands that wish to let para_server store
408 * arbitrary data specified by the user (for instance the add_blob family of
409 * commands). First, at most \a max_len bytes are read from \a fd, the result
410 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
411 * is made available to the parent process via shared memory.
412 *
413 * \return Negative on errors, the return value of the underlying call to
414 * send_callback_request() otherwise.
415 */
416 int stdin_command(int fd, struct osl_object *arg_obj, callback_function *f,
417 unsigned max_len, struct osl_object *result)
418 {
419 struct osl_object query, stdin_obj;
420 int ret;
421
422 ret = send_buffer(fd, AWAITING_DATA_MSG);
423 if (ret < 0)
424 return ret;
425 ret = fd2buf(fd, max_len, &stdin_obj);
426 if (ret < 0)
427 return ret;
428 query.size = arg_obj->size + stdin_obj.size;
429 query.data = para_malloc(query.size);
430 memcpy(query.data, arg_obj->data, arg_obj->size);
431 memcpy((char *)query.data + arg_obj->size, stdin_obj.data, stdin_obj.size);
432 free(stdin_obj.data);
433 ret = send_callback_request(f, &query, result);
434 free(query.data);
435 return ret;
436 }
437
438 static int pass_afd(int fd, char *buf, size_t size)
439 {
440 struct msghdr msg = {.msg_iov = NULL};
441 struct cmsghdr *cmsg;
442 char control[255];
443 int ret;
444 struct iovec iov;
445
446 iov.iov_base = buf;
447 iov.iov_len = size;
448
449 msg.msg_iov = &iov;
450 msg.msg_iovlen = 1;
451
452 msg.msg_control = control;
453 msg.msg_controllen = sizeof(control);
454
455 cmsg = CMSG_FIRSTHDR(&msg);
456 cmsg->cmsg_level = SOL_SOCKET;
457 cmsg->cmsg_type = SCM_RIGHTS;
458 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
459 *(int *)CMSG_DATA(cmsg) = fd;
460
461 /* Sum of the length of all control messages in the buffer */
462 msg.msg_controllen = cmsg->cmsg_len;
463 PARA_DEBUG_LOG("passing %zu bytes and fd %d\n", size, fd);
464 ret = sendmsg(server_socket, &msg, 0);
465 if (ret < 0) {
466 ret = -ERRNO_TO_PARA_ERROR(errno);
467 return ret;
468 }
469 return 1;
470 }
471
472 /**
473 * Open the audio file with highest score.
474 *
475 * This stores all information for streaming the "best" audio file in a shared
476 * memory area. The id of that area and an open file descriptor for the next
477 * audio file are passed to the server process.
478 *
479 * \return Standard.
480 *
481 * \sa open_and_update_audio_file().
482 */
483 int open_next_audio_file(void)
484 {
485 struct osl_row *aft_row;
486 struct audio_file_data afd;
487 int ret, shmid;
488 char buf[8];
489
490 PARA_NOTICE_LOG("getting next audio file\n");
491 ret = score_get_best(&aft_row, &afd.score);
492 if (ret < 0)
493 return ret;
494 ret = open_and_update_audio_file(aft_row, &afd);
495 if (ret < 0)
496 return ret;
497 shmid = ret;
498 if (!write_ok(server_socket)) {
499 PARA_EMERG_LOG("afs_socket not writable\n");
500 goto destroy;
501 }
502 *(uint32_t *)buf = NEXT_AUDIO_FILE;
503 *(uint32_t *)(buf + 4) = (uint32_t)shmid;
504 ret = pass_afd(afd.fd, buf, 8);
505 close(afd.fd);
506 if (ret >= 0)
507 return ret;
508 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
509 destroy:
510 shm_destroy(shmid);
511 return ret;
512 }
513
514 /* Never fails if arg == NULL */
515 static int activate_mood_or_playlist(char *arg, int *num_admissible)
516 {
517 enum play_mode mode;
518 int ret;
519
520 if (!arg) {
521 ret = change_current_mood(NULL); /* always successful */
522 mode = PLAY_MODE_MOOD;
523 } else {
524 if (!strncmp(arg, "p:", 2)) {
525 ret = playlist_open(arg + 2);
526 mode = PLAY_MODE_PLAYLIST;
527 } else if (!strncmp(arg, "m:", 2)) {
528 ret = change_current_mood(arg + 2);
529 mode = PLAY_MODE_MOOD;
530 } else
531 ret = -E_AFS_SYNTAX;
532 if (ret < 0)
533 return ret;
534 }
535 if (num_admissible)
536 *num_admissible = ret;
537 current_play_mode = mode;
538 if (arg != current_mop) {
539 free(current_mop);
540 if (arg) {
541 current_mop = para_strdup(arg);
542 mmd_lock();
543 strcpy(mmd->afs_mode_string, arg); /* FIXME: check length */
544 mmd_unlock();
545 } else {
546 mmd_lock();
547 strcpy(mmd->afs_mode_string, "dummy");
548 mmd_unlock();
549 current_mop = NULL;
550 }
551 }
552 return 1;
553 }
554
555 static int com_select_callback(const struct osl_object *query,
556 struct osl_object *result)
557 {
558 struct para_buffer pb = {.buf = NULL};
559 char *arg = query->data;
560 int num_admissible, ret;
561
562 ret = clear_score_table();
563 if (ret < 0)
564 return ret;
565 if (current_play_mode == PLAY_MODE_MOOD)
566 close_current_mood();
567 else
568 playlist_close();
569 ret = activate_mood_or_playlist(arg, &num_admissible);
570 if (ret < 0) {
571 para_printf(&pb, "%s\n", PARA_STRERROR(-ret));
572 para_printf(&pb, "switching back to %s\n", current_mop?
573 current_mop : "dummy");
574 ret = activate_mood_or_playlist(current_mop, &num_admissible);
575 if (ret < 0) {
576 para_printf(&pb, "failed, switching to dummy\n");
577 activate_mood_or_playlist(NULL, &num_admissible);
578 }
579 }
580 para_printf(&pb, "activated %s (%d admissible files)\n", current_mop?
581 current_mop : "dummy mood", num_admissible);
582 result->data = pb.buf;
583 result->size = pb.size;
584 return 1;
585 }
586
587 int com_select(int fd, int argc, char * const * const argv)
588 {
589 int ret;
590 struct osl_object query, result;
591
592 if (argc != 2)
593 return -E_AFS_SYNTAX;
594 query.data = argv[1];
595 query.size = strlen(argv[1]) + 1;
596 ret = send_callback_request(com_select_callback, &query,
597 &result);
598 if (ret > 0 && result.data && result.size) {
599 ret = send_va_buffer(fd, "%s", (char *)result.data);
600 free(result.data);
601 }
602 return ret;
603 }
604
605 static void init_admissible_files(char *arg)
606 {
607 if (activate_mood_or_playlist(arg, NULL) < 0)
608 activate_mood_or_playlist(NULL, NULL); /* always successful */
609 }
610
611 static int setup_command_socket_or_die(void)
612 {
613 int ret;
614 char *socket_name = conf.afs_socket_arg;
615 struct sockaddr_un unix_addr;
616
617 unlink(socket_name);
618 ret = create_local_socket(socket_name, &unix_addr,
619 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
620 if (ret < 0) {
621 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
622 exit(EXIT_FAILURE);
623 }
624 if (listen(ret , 5) < 0) {
625 PARA_EMERG_LOG("%s", "can not listen on socket\n");
626 exit(EXIT_FAILURE);
627 }
628 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
629 ret);
630 return ret;
631 }
632
633 static void close_afs_tables(void)
634 {
635 int i;
636 PARA_NOTICE_LOG("closing afs_tables\n");
637 for (i = 0; i < NUM_AFS_TABLES; i++)
638 afs_tables[i].close();
639 }
640
641 static char *database_dir;
642
643 static void get_database_dir(void)
644 {
645 if (!database_dir) {
646 if (conf.afs_database_dir_given)
647 database_dir = para_strdup(conf.afs_database_dir_arg);
648 else {
649 char *home = para_homedir();
650 database_dir = make_message(
651 "%s/.paraslash/afs_database", home);
652 free(home);
653 }
654 }
655 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
656 }
657
658 static int make_database_dir(void)
659 {
660 int ret;
661
662 get_database_dir();
663 ret = para_mkdir(database_dir, 0777);
664 if (ret >= 0 || is_errno(-ret, EEXIST))
665 return 1;
666 return ret;
667 }
668
669 static int open_afs_tables(void)
670 {
671 int i, ret;
672
673 get_database_dir();
674 PARA_NOTICE_LOG("opening %u osl tables in %s\n", NUM_AFS_TABLES,
675 database_dir);
676 for (i = 0; i < NUM_AFS_TABLES; i++) {
677 ret = afs_tables[i].open(database_dir);
678 if (ret >= 0)
679 continue;
680 PARA_ERROR_LOG("%s init: %s\n", afs_tables[i].name,
681 PARA_STRERROR(-ret));
682 break;
683 }
684 if (ret >= 0)
685 return ret;
686 while (i)
687 afs_tables[--i].close();
688 return ret;
689 }
690
691 static void unregister_tasks(void)
692 {
693 unregister_task(&command_task_struct.task);
694 unregister_task(&signal_task_struct.task);
695 }
696
697 static void signal_pre_select(struct sched *s, struct task *t)
698 {
699 struct signal_task *st = t->private_data;
700 t->ret = 1;
701 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
702 }
703
704 static void signal_post_select(struct sched *s, struct task *t)
705 {
706 struct signal_task *st = t->private_data;
707 t->ret = -E_AFS_PARENT_DIED;
708 if (getppid() == 1)
709 goto err;
710 t->ret = 1;
711 if (!FD_ISSET(st->fd, &s->rfds))
712 return;
713 st->signum = para_next_signal();
714 t->ret = 1;
715 if (st->signum == SIGUSR1)
716 return; /* ignore SIGUSR1 */
717 if (st->signum == SIGHUP) {
718 close_afs_tables();
719 t->ret = open_afs_tables();
720 if (t->ret < 0)
721 goto err;
722 init_admissible_files(current_mop);
723 return;
724 }
725 t->ret = -E_AFS_SIGNAL;
726 err:
727 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
728 unregister_tasks();
729 }
730
731 static void register_signal_task(void)
732 {
733 struct signal_task *st = &signal_task_struct;
734 st->fd = para_signal_init();
735 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
736 para_install_sighandler(SIGINT);
737 para_install_sighandler(SIGTERM);
738 para_install_sighandler(SIGPIPE);
739 para_install_sighandler(SIGHUP);
740
741 st->task.pre_select = signal_pre_select;
742 st->task.post_select = signal_post_select;
743 st->task.private_data = st;
744 sprintf(st->task.status, "signal task");
745 register_task(&st->task);
746 }
747
748 static struct list_head afs_client_list;
749
750 struct afs_client {
751 struct list_head node;
752 int fd;
753 struct timeval connect_time;
754 };
755
756 static void command_pre_select(struct sched *s, struct task *t)
757 {
758 struct command_task *ct = t->private_data;
759 struct afs_client *client;
760
761 para_fd_set(server_socket, &s->rfds, &s->max_fileno);
762 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
763 list_for_each_entry(client, &afs_client_list, node)
764 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
765 t->ret = 1;
766 }
767
768 /*
769 * On errors, negative value is written to fd.
770 * On success: If query produced a result, the result_shmid is written to fd.
771 * Otherwise, zero is written.
772 */
773 static int call_callback(int fd, int query_shmid)
774 {
775 void *query_shm, *result_shm;
776 struct callback_query *cq;
777 struct callback_result *cr;
778 struct osl_object query, result = {.data = NULL};
779 int result_shmid = -1, ret, ret2;
780
781 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
782 if (ret < 0)
783 goto out;
784 cq = query_shm;
785 query.data = (char *)query_shm + sizeof(*cq);
786 query.size = cq->query_size;
787 ret = cq->handler(&query, &result);
788 ret2 = shm_detach(query_shm);
789 if (ret2 < 0 && ret >= 0)
790 ret = ret2;
791 if (ret < 0)
792 goto out;
793 ret = 0;
794 if (!result.data || !result.size)
795 goto out;
796 ret = shm_new(result.size + sizeof(struct callback_result));
797 if (ret < 0)
798 goto out;
799 result_shmid = ret;
800 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
801 if (ret < 0)
802 goto out;
803 cr = result_shm;
804 cr->result_size = result.size;
805 memcpy(result_shm + sizeof(*cr), result.data, result.size);
806 ret = shm_detach(result_shm);
807 if (ret < 0)
808 goto out;
809 ret = result_shmid;
810 out:
811 free(result.data);
812 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
813 if (ret < 0 || ret2 < 0) {
814 if (result_shmid >= 0)
815 if (shm_destroy(result_shmid) < 0)
816 PARA_ERROR_LOG("destroy result failed\n");
817 if (ret >= 0)
818 ret = ret2;
819 }
820 return ret;
821 }
822
823 static void execute_server_command(void)
824 {
825 char buf[8];
826 int ret = recv_bin_buffer(server_socket, buf, sizeof(buf) - 1);
827
828 if (ret <= 0) {
829 if (ret < 0)
830 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
831 return;
832 }
833 buf[ret] = '\0';
834 PARA_DEBUG_LOG("received: %s\n", buf);
835 if (!strcmp(buf, "new")) {
836 ret = open_next_audio_file();
837 if (ret < 0)
838 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
839 return;
840 }
841 PARA_ERROR_LOG("unknown command\n");
842
843 }
844
845 static void execute_afs_command(int fd, uint32_t expected_cookie)
846 {
847 uint32_t cookie;
848 int query_shmid;
849 char buf[sizeof(cookie) + sizeof(query_shmid)];
850 int ret = recv_bin_buffer(fd, buf, sizeof(buf));
851
852 if (ret < 0) {
853 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
854 return;
855 }
856 if (ret != sizeof(buf)) {
857 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
858 ret, (long unsigned) sizeof(buf));
859 return;
860 }
861 cookie = *(uint32_t *)buf;
862 if (cookie != expected_cookie) {
863 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
864 (unsigned)cookie, (unsigned)expected_cookie);
865 return;
866 }
867 query_shmid = *(int *)(buf + sizeof(cookie));
868 if (query_shmid < 0) {
869 PARA_WARNING_LOG("received invalid query shmid %d)\n",
870 query_shmid);
871 return;
872 }
873 /* Ignore return value: Errors might be OK here. */
874 call_callback(fd, query_shmid);
875 }
876
877 /** Shutdown connection if query has not arrived until this many seconds. */
878 #define AFS_CLIENT_TIMEOUT 3
879
880 static void command_post_select(struct sched *s, struct task *t)
881 {
882 struct command_task *ct = t->private_data;
883 struct sockaddr_un unix_addr;
884 struct afs_client *client, *tmp;
885
886 if (FD_ISSET(server_socket, &s->rfds))
887 execute_server_command();
888
889 /* Check the list of connected clients. */
890 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
891 if (FD_ISSET(client->fd, &s->rfds))
892 execute_afs_command(client->fd, ct->cookie);
893 else { /* prevent bogus connection flooding */
894 struct timeval diff;
895 tv_diff(now, &client->connect_time, &diff);
896 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
897 continue;
898 PARA_WARNING_LOG("connection timeout\n");
899 }
900 close(client->fd);
901 list_del(&client->node);
902 free(client);
903 }
904 /* Accept connections on the local socket. */
905 if (!FD_ISSET(ct->fd, &s->rfds))
906 goto out;
907 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
908 if (t->ret < 0) {
909 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
910 goto out;
911 }
912 client = para_malloc(sizeof(*client));
913 client->fd = t->ret;
914 client->connect_time = *now;
915 para_list_add(&client->node, &afs_client_list);
916 out:
917 t->ret = 1;
918 }
919
920 static void register_command_task(uint32_t cookie)
921 {
922 struct command_task *ct = &command_task_struct;
923 ct->fd = setup_command_socket_or_die();
924 ct->cookie = cookie;
925
926 ct->task.pre_select = command_pre_select;
927 ct->task.post_select = command_post_select;
928 ct->task.private_data = ct;
929 sprintf(ct->task.status, "command task");
930 register_task(&ct->task);
931 }
932
933 static void register_tasks(uint32_t cookie)
934 {
935 register_signal_task();
936 register_command_task(cookie);
937 }
938
939 /**
940 * Initialize the audio file selector process.
941 *
942 * \param cookie The value used for "authentication".
943 * \param socket_fd File descriptor used for communication with the server.
944 */
945 __noreturn void afs_init(uint32_t cookie, int socket_fd)
946 {
947 struct sched s;
948 int i, ret;
949
950 INIT_LIST_HEAD(&afs_client_list);
951 for (i = 0; i < NUM_AFS_TABLES; i++)
952 afs_tables[i].init(&afs_tables[i]);
953 ret = open_afs_tables();
954
955 if (ret < 0) {
956 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
957 exit(EXIT_FAILURE);
958 }
959 server_socket = socket_fd;
960 ret = mark_fd_nonblock(server_socket);
961 if (ret < 0)
962 exit(EXIT_FAILURE);
963 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
964 server_socket, (unsigned) cookie);
965 init_admissible_files(conf.afs_initial_mode_arg);
966 register_tasks(cookie);
967 s.default_timeout.tv_sec = 0;
968 s.default_timeout.tv_usec = 999 * 1000;
969 ret = sched(&s);
970 if (ret < 0)
971 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
972 close_afs_tables();
973 exit(EXIT_FAILURE);
974 }
975
976 static int create_tables_callback(const struct osl_object *query,
977 __a_unused struct osl_object *result)
978 {
979 uint32_t table_mask = *(uint32_t *)query->data;
980 int i, ret;
981
982 close_afs_tables();
983 for (i = 0; i < NUM_AFS_TABLES; i++) {
984 struct afs_table *t = &afs_tables[i];
985
986 if (!(table_mask & (1 << i)))
987 continue;
988 if (!t->create)
989 continue;
990 ret = t->create(database_dir);
991 if (ret < 0)
992 return ret;
993 }
994 ret = open_afs_tables();
995 return ret < 0? ret: 0;
996 }
997
998 int com_init(int fd, int argc, char * const * const argv)
999 {
1000 int i, j, ret;
1001 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
1002 struct osl_object query = {.data = &table_mask,
1003 .size = sizeof(table_mask)};
1004
1005 ret = make_database_dir();
1006 if (ret < 0)
1007 return ret;
1008 if (argc != 1) {
1009 table_mask = 0;
1010 for (i = 1; i < argc; i++) {
1011 for (j = 0; j < NUM_AFS_TABLES; j++) {
1012 struct afs_table *t = &afs_tables[j];
1013
1014 if (strcmp(argv[i], t->name))
1015 continue;
1016 table_mask |= (1 << j);
1017 break;
1018 }
1019 if (j == NUM_AFS_TABLES)
1020 return -E_BAD_TABLE_NAME;
1021 }
1022 }
1023 ret = send_callback_request(create_tables_callback, &query, NULL);
1024 if (ret < 0)
1025 return ret;
1026 return send_va_buffer(fd, "successfully created afs table(s)\n");
1027 }
1028
1029 /**
1030 * Flags for the check command.
1031 *
1032 * \sa com_check().
1033 */
1034 enum com_check_flags {
1035 /** Check the audio file table. */
1036 CHECK_AFT = 1,
1037 /** Check the mood table. */
1038 CHECK_MOODS = 2,
1039 /** Check the playlist table. */
1040 CHECK_PLAYLISTS = 4
1041 };
1042
1043 int com_check(int fd, int argc, char * const * const argv)
1044 {
1045 unsigned flags = 0;
1046 int i, ret;
1047 struct osl_object result;
1048
1049 for (i = 1; i < argc; i++) {
1050 const char *arg = argv[i];
1051 if (arg[0] != '-')
1052 break;
1053 if (!strcmp(arg, "--")) {
1054 i++;
1055 break;
1056 }
1057 if (!strcmp(arg, "-a")) {
1058 flags |= CHECK_AFT;
1059 continue;
1060 }
1061 if (!strcmp(arg, "-p")) {
1062 flags |= CHECK_PLAYLISTS;
1063 continue;
1064 }
1065 if (!strcmp(arg, "-m")) {
1066 flags |= CHECK_MOODS;
1067 continue;
1068 }
1069 return -E_AFS_SYNTAX;
1070 }
1071 if (i < argc)
1072 return -E_AFS_SYNTAX;
1073 if (!flags)
1074 flags = ~0U;
1075 if (flags & CHECK_AFT) {
1076 ret = send_callback_request(aft_check_callback, NULL, &result);
1077 if (ret < 0)
1078 return ret;
1079 if (ret > 0) {
1080 ret = send_buffer(fd, (char *) result.data);
1081 free(result.data);
1082 if (ret < 0)
1083 return ret;
1084 }
1085 }
1086 if (flags & CHECK_PLAYLISTS) {
1087 ret = send_callback_request(playlist_check_callback, NULL, &result);
1088 if (ret < 0)
1089 return ret;
1090 if (ret > 0) {
1091 ret = send_buffer(fd, (char *) result.data);
1092 free(result.data);
1093 if (ret < 0)
1094 return ret;
1095 }
1096 }
1097 if (flags & CHECK_MOODS) {
1098 ret = send_callback_request(mood_check_callback, NULL, &result);
1099 if (ret < 0)
1100 return ret;
1101 if (ret > 0) {
1102 ret = send_buffer(fd, (char *) result.data);
1103 free(result.data);
1104 if (ret < 0)
1105 return ret;
1106 }
1107 }
1108 return 1;
1109 }
1110
1111 void afs_event(enum afs_events event, struct para_buffer *pb,
1112 void *data)
1113 {
1114 int i, ret;
1115
1116 for (i = 0; i < NUM_AFS_TABLES; i++) {
1117 struct afs_table *t = &afs_tables[i];
1118 if (!t->event_handler)
1119 continue;
1120 ret = t->event_handler(event, pb, data);
1121 if (ret < 0)
1122 PARA_CRIT_LOG("%s\n", PARA_STRERROR(-ret));
1123 }
1124 }
1125
1126 int images_event_handler(__a_unused enum afs_events event,
1127 __a_unused struct para_buffer *pb, __a_unused void *data)
1128 {
1129 return 1;
1130 }
1131
1132 int lyrics_event_handler(__a_unused enum afs_events event,
1133 __a_unused struct para_buffer *pb, __a_unused void *data)
1134 {
1135 return 1;
1136 }