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