Set more file descriptors to non-blocking mode.
[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 strncpy(mmd->afs_mode_string, arg,
544 sizeof(mmd->afs_mode_string));
545 mmd->afs_mode_string[sizeof(mmd->afs_mode_string) - 1] = '\0';
546 mmd_unlock();
547 } else {
548 mmd_lock();
549 strcpy(mmd->afs_mode_string, "dummy");
550 mmd_unlock();
551 current_mop = NULL;
552 }
553 }
554 return 1;
555 }
556
557 static int com_select_callback(const struct osl_object *query,
558 struct osl_object *result)
559 {
560 struct para_buffer pb = {.buf = NULL};
561 char *arg = query->data;
562 int num_admissible, ret;
563
564 ret = clear_score_table();
565 if (ret < 0)
566 return ret;
567 if (current_play_mode == PLAY_MODE_MOOD)
568 close_current_mood();
569 else
570 playlist_close();
571 ret = activate_mood_or_playlist(arg, &num_admissible);
572 if (ret < 0) {
573 para_printf(&pb, "%s\n", PARA_STRERROR(-ret));
574 para_printf(&pb, "switching back to %s\n", current_mop?
575 current_mop : "dummy");
576 ret = activate_mood_or_playlist(current_mop, &num_admissible);
577 if (ret < 0) {
578 para_printf(&pb, "failed, switching to dummy\n");
579 activate_mood_or_playlist(NULL, &num_admissible);
580 }
581 }
582 para_printf(&pb, "activated %s (%d admissible files)\n", current_mop?
583 current_mop : "dummy mood", num_admissible);
584 result->data = pb.buf;
585 result->size = pb.size;
586 return 1;
587 }
588
589 int com_select(int fd, int argc, char * const * const argv)
590 {
591 int ret;
592 struct osl_object query, result;
593
594 if (argc != 2)
595 return -E_AFS_SYNTAX;
596 query.data = argv[1];
597 query.size = strlen(argv[1]) + 1;
598 ret = send_callback_request(com_select_callback, &query,
599 &result);
600 if (ret > 0 && result.data && result.size) {
601 ret = send_va_buffer(fd, "%s", (char *)result.data);
602 free(result.data);
603 }
604 return ret;
605 }
606
607 static void init_admissible_files(char *arg)
608 {
609 if (activate_mood_or_playlist(arg, NULL) < 0)
610 activate_mood_or_playlist(NULL, NULL); /* always successful */
611 }
612
613 static int setup_command_socket_or_die(void)
614 {
615 int ret, socket_fd;
616 char *socket_name = conf.afs_socket_arg;
617 struct sockaddr_un unix_addr;
618
619 unlink(socket_name);
620 ret = create_local_socket(socket_name, &unix_addr,
621 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
622 if (ret < 0) {
623 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
624 exit(EXIT_FAILURE);
625 }
626 socket_fd = ret;
627 if (listen(socket_fd , 5) < 0) {
628 PARA_EMERG_LOG("can not listen on socket\n");
629 exit(EXIT_FAILURE);
630 }
631 ret = mark_fd_nonblock(socket_fd);
632 if (ret < 0) {
633 close(socket_fd);
634 return ret;
635 }
636 PARA_INFO_LOG("listening on socket %s (fd %d)\n", socket_name, ret);
637 return socket_fd;
638 }
639
640 static void close_afs_tables(void)
641 {
642 int i;
643 PARA_NOTICE_LOG("closing afs_tables\n");
644 for (i = 0; i < NUM_AFS_TABLES; i++)
645 afs_tables[i].close();
646 }
647
648 static char *database_dir;
649
650 static void get_database_dir(void)
651 {
652 if (!database_dir) {
653 if (conf.afs_database_dir_given)
654 database_dir = para_strdup(conf.afs_database_dir_arg);
655 else {
656 char *home = para_homedir();
657 database_dir = make_message(
658 "%s/.paraslash/afs_database", home);
659 free(home);
660 }
661 }
662 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
663 }
664
665 static int make_database_dir(void)
666 {
667 int ret;
668
669 get_database_dir();
670 ret = para_mkdir(database_dir, 0777);
671 if (ret >= 0 || is_errno(-ret, EEXIST))
672 return 1;
673 return ret;
674 }
675
676 static int open_afs_tables(void)
677 {
678 int i, ret;
679
680 get_database_dir();
681 PARA_NOTICE_LOG("opening %u osl tables in %s\n", NUM_AFS_TABLES,
682 database_dir);
683 for (i = 0; i < NUM_AFS_TABLES; i++) {
684 ret = afs_tables[i].open(database_dir);
685 if (ret >= 0)
686 continue;
687 PARA_ERROR_LOG("%s init: %s\n", afs_tables[i].name,
688 PARA_STRERROR(-ret));
689 break;
690 }
691 if (ret >= 0)
692 return ret;
693 while (i)
694 afs_tables[--i].close();
695 return ret;
696 }
697
698 static void unregister_tasks(void)
699 {
700 unregister_task(&command_task_struct.task);
701 unregister_task(&signal_task_struct.task);
702 }
703
704 static void signal_pre_select(struct sched *s, struct task *t)
705 {
706 struct signal_task *st = t->private_data;
707 t->ret = 1;
708 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
709 }
710
711 static void signal_post_select(struct sched *s, struct task *t)
712 {
713 struct signal_task *st = t->private_data;
714 t->ret = -E_AFS_PARENT_DIED;
715 if (getppid() == 1)
716 goto err;
717 t->ret = 1;
718 if (!FD_ISSET(st->fd, &s->rfds))
719 return;
720 st->signum = para_next_signal();
721 t->ret = 1;
722 if (st->signum == SIGUSR1)
723 return; /* ignore SIGUSR1 */
724 if (st->signum == SIGHUP) {
725 close_afs_tables();
726 t->ret = open_afs_tables();
727 if (t->ret < 0)
728 goto err;
729 init_admissible_files(current_mop);
730 return;
731 }
732 t->ret = -E_AFS_SIGNAL;
733 err:
734 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
735 unregister_tasks();
736 }
737
738 static void register_signal_task(void)
739 {
740 struct signal_task *st = &signal_task_struct;
741 st->fd = para_signal_init();
742 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
743 para_install_sighandler(SIGINT);
744 para_install_sighandler(SIGTERM);
745 para_install_sighandler(SIGPIPE);
746 para_install_sighandler(SIGHUP);
747
748 st->task.pre_select = signal_pre_select;
749 st->task.post_select = signal_post_select;
750 st->task.private_data = st;
751 sprintf(st->task.status, "signal task");
752 register_task(&st->task);
753 }
754
755 static struct list_head afs_client_list;
756
757 struct afs_client {
758 struct list_head node;
759 int fd;
760 struct timeval connect_time;
761 };
762
763 static void command_pre_select(struct sched *s, struct task *t)
764 {
765 struct command_task *ct = t->private_data;
766 struct afs_client *client;
767
768 para_fd_set(server_socket, &s->rfds, &s->max_fileno);
769 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
770 list_for_each_entry(client, &afs_client_list, node)
771 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
772 t->ret = 1;
773 }
774
775 /*
776 * On errors, negative value is written to fd.
777 * On success: If query produced a result, the result_shmid is written to fd.
778 * Otherwise, zero is written.
779 */
780 static int call_callback(int fd, int query_shmid)
781 {
782 void *query_shm, *result_shm;
783 struct callback_query *cq;
784 struct callback_result *cr;
785 struct osl_object query, result = {.data = NULL};
786 int result_shmid = -1, ret, ret2;
787
788 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
789 if (ret < 0)
790 goto out;
791 cq = query_shm;
792 query.data = (char *)query_shm + sizeof(*cq);
793 query.size = cq->query_size;
794 ret = cq->handler(&query, &result);
795 ret2 = shm_detach(query_shm);
796 if (ret2 < 0 && ret >= 0)
797 ret = ret2;
798 if (ret < 0)
799 goto out;
800 ret = 0;
801 if (!result.data || !result.size)
802 goto out;
803 ret = shm_new(result.size + sizeof(struct callback_result));
804 if (ret < 0)
805 goto out;
806 result_shmid = ret;
807 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
808 if (ret < 0)
809 goto out;
810 cr = result_shm;
811 cr->result_size = result.size;
812 memcpy(result_shm + sizeof(*cr), result.data, result.size);
813 ret = shm_detach(result_shm);
814 if (ret < 0)
815 goto out;
816 ret = result_shmid;
817 out:
818 free(result.data);
819 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
820 if (ret < 0 || ret2 < 0) {
821 if (result_shmid >= 0)
822 if (shm_destroy(result_shmid) < 0)
823 PARA_ERROR_LOG("destroy result failed\n");
824 if (ret >= 0)
825 ret = ret2;
826 }
827 return ret;
828 }
829
830 static void execute_server_command(void)
831 {
832 char buf[8];
833 int ret = recv_bin_buffer(server_socket, buf, sizeof(buf) - 1);
834
835 if (ret <= 0) {
836 if (ret < 0)
837 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
838 return;
839 }
840 buf[ret] = '\0';
841 PARA_DEBUG_LOG("received: %s\n", buf);
842 if (!strcmp(buf, "new")) {
843 ret = open_next_audio_file();
844 if (ret < 0)
845 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
846 return;
847 }
848 PARA_ERROR_LOG("unknown command\n");
849
850 }
851
852 static void execute_afs_command(int fd, uint32_t expected_cookie)
853 {
854 uint32_t cookie;
855 int query_shmid;
856 char buf[sizeof(cookie) + sizeof(query_shmid)];
857 int ret = recv_bin_buffer(fd, buf, sizeof(buf));
858
859 if (ret < 0) {
860 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
861 return;
862 }
863 if (ret != sizeof(buf)) {
864 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
865 ret, (long unsigned) sizeof(buf));
866 return;
867 }
868 cookie = *(uint32_t *)buf;
869 if (cookie != expected_cookie) {
870 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
871 (unsigned)cookie, (unsigned)expected_cookie);
872 return;
873 }
874 query_shmid = *(int *)(buf + sizeof(cookie));
875 if (query_shmid < 0) {
876 PARA_WARNING_LOG("received invalid query shmid %d)\n",
877 query_shmid);
878 return;
879 }
880 /* Ignore return value: Errors might be OK here. */
881 call_callback(fd, query_shmid);
882 }
883
884 /** Shutdown connection if query has not arrived until this many seconds. */
885 #define AFS_CLIENT_TIMEOUT 3
886
887 static void command_post_select(struct sched *s, struct task *t)
888 {
889 struct command_task *ct = t->private_data;
890 struct sockaddr_un unix_addr;
891 struct afs_client *client, *tmp;
892 int fd;
893 if (FD_ISSET(server_socket, &s->rfds))
894 execute_server_command();
895
896 /* Check the list of connected clients. */
897 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
898 if (FD_ISSET(client->fd, &s->rfds))
899 execute_afs_command(client->fd, ct->cookie);
900 else { /* prevent bogus connection flooding */
901 struct timeval diff;
902 tv_diff(now, &client->connect_time, &diff);
903 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
904 continue;
905 PARA_WARNING_LOG("connection timeout\n");
906 }
907 close(client->fd);
908 list_del(&client->node);
909 free(client);
910 }
911 /* Accept connections on the local socket. */
912 if (!FD_ISSET(ct->fd, &s->rfds))
913 goto out;
914 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
915 if (t->ret < 0) {
916 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
917 goto out;
918 }
919 fd = t->ret;
920 t->ret = mark_fd_nonblock(fd);
921 if (t->ret < 0) {
922 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
923 close(fd);
924 goto out;
925 }
926 client = para_malloc(sizeof(*client));
927 client->fd = fd;
928 client->connect_time = *now;
929 para_list_add(&client->node, &afs_client_list);
930 out:
931 t->ret = 1;
932 }
933
934 static void register_command_task(uint32_t cookie)
935 {
936 struct command_task *ct = &command_task_struct;
937 ct->fd = setup_command_socket_or_die();
938 ct->cookie = cookie;
939
940 ct->task.pre_select = command_pre_select;
941 ct->task.post_select = command_post_select;
942 ct->task.private_data = ct;
943 sprintf(ct->task.status, "command task");
944 register_task(&ct->task);
945 }
946
947 static void register_tasks(uint32_t cookie)
948 {
949 register_signal_task();
950 register_command_task(cookie);
951 }
952
953 /**
954 * Initialize the audio file selector process.
955 *
956 * \param cookie The value used for "authentication".
957 * \param socket_fd File descriptor used for communication with the server.
958 */
959 __noreturn void afs_init(uint32_t cookie, int socket_fd)
960 {
961 struct sched s;
962 int i, ret;
963
964 INIT_LIST_HEAD(&afs_client_list);
965 for (i = 0; i < NUM_AFS_TABLES; i++)
966 afs_tables[i].init(&afs_tables[i]);
967 ret = open_afs_tables();
968
969 if (ret < 0) {
970 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
971 exit(EXIT_FAILURE);
972 }
973 server_socket = socket_fd;
974 ret = mark_fd_nonblock(server_socket);
975 if (ret < 0)
976 exit(EXIT_FAILURE);
977 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
978 server_socket, (unsigned) cookie);
979 init_admissible_files(conf.afs_initial_mode_arg);
980 register_tasks(cookie);
981 s.default_timeout.tv_sec = 0;
982 s.default_timeout.tv_usec = 999 * 1000;
983 ret = sched(&s);
984 if (ret < 0)
985 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
986 close_afs_tables();
987 exit(EXIT_FAILURE);
988 }
989
990 static int create_tables_callback(const struct osl_object *query,
991 __a_unused struct osl_object *result)
992 {
993 uint32_t table_mask = *(uint32_t *)query->data;
994 int i, ret;
995
996 close_afs_tables();
997 for (i = 0; i < NUM_AFS_TABLES; i++) {
998 struct afs_table *t = &afs_tables[i];
999
1000 if (!(table_mask & (1 << i)))
1001 continue;
1002 if (!t->create)
1003 continue;
1004 ret = t->create(database_dir);
1005 if (ret < 0)
1006 return ret;
1007 }
1008 ret = open_afs_tables();
1009 return ret < 0? ret: 0;
1010 }
1011
1012 int com_init(int fd, int argc, char * const * const argv)
1013 {
1014 int i, j, ret;
1015 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
1016 struct osl_object query = {.data = &table_mask,
1017 .size = sizeof(table_mask)};
1018
1019 ret = make_database_dir();
1020 if (ret < 0)
1021 return ret;
1022 if (argc != 1) {
1023 table_mask = 0;
1024 for (i = 1; i < argc; i++) {
1025 for (j = 0; j < NUM_AFS_TABLES; j++) {
1026 struct afs_table *t = &afs_tables[j];
1027
1028 if (strcmp(argv[i], t->name))
1029 continue;
1030 table_mask |= (1 << j);
1031 break;
1032 }
1033 if (j == NUM_AFS_TABLES)
1034 return -E_BAD_TABLE_NAME;
1035 }
1036 }
1037 ret = send_callback_request(create_tables_callback, &query, NULL);
1038 if (ret < 0)
1039 return ret;
1040 return send_va_buffer(fd, "successfully created afs table(s)\n");
1041 }
1042
1043 /**
1044 * Flags for the check command.
1045 *
1046 * \sa com_check().
1047 */
1048 enum com_check_flags {
1049 /** Check the audio file table. */
1050 CHECK_AFT = 1,
1051 /** Check the mood table. */
1052 CHECK_MOODS = 2,
1053 /** Check the playlist table. */
1054 CHECK_PLAYLISTS = 4
1055 };
1056
1057 int com_check(int fd, int argc, char * const * const argv)
1058 {
1059 unsigned flags = 0;
1060 int i, ret;
1061 struct osl_object result;
1062
1063 for (i = 1; i < argc; i++) {
1064 const char *arg = argv[i];
1065 if (arg[0] != '-')
1066 break;
1067 if (!strcmp(arg, "--")) {
1068 i++;
1069 break;
1070 }
1071 if (!strcmp(arg, "-a")) {
1072 flags |= CHECK_AFT;
1073 continue;
1074 }
1075 if (!strcmp(arg, "-p")) {
1076 flags |= CHECK_PLAYLISTS;
1077 continue;
1078 }
1079 if (!strcmp(arg, "-m")) {
1080 flags |= CHECK_MOODS;
1081 continue;
1082 }
1083 return -E_AFS_SYNTAX;
1084 }
1085 if (i < argc)
1086 return -E_AFS_SYNTAX;
1087 if (!flags)
1088 flags = ~0U;
1089 if (flags & CHECK_AFT) {
1090 ret = send_callback_request(aft_check_callback, NULL, &result);
1091 if (ret < 0)
1092 return ret;
1093 if (ret > 0) {
1094 ret = send_buffer(fd, (char *) result.data);
1095 free(result.data);
1096 if (ret < 0)
1097 return ret;
1098 }
1099 }
1100 if (flags & CHECK_PLAYLISTS) {
1101 ret = send_callback_request(playlist_check_callback, NULL, &result);
1102 if (ret < 0)
1103 return ret;
1104 if (ret > 0) {
1105 ret = send_buffer(fd, (char *) result.data);
1106 free(result.data);
1107 if (ret < 0)
1108 return ret;
1109 }
1110 }
1111 if (flags & CHECK_MOODS) {
1112 ret = send_callback_request(mood_check_callback, NULL, &result);
1113 if (ret < 0)
1114 return ret;
1115 if (ret > 0) {
1116 ret = send_buffer(fd, (char *) result.data);
1117 free(result.data);
1118 if (ret < 0)
1119 return ret;
1120 }
1121 }
1122 return 1;
1123 }
1124
1125 void afs_event(enum afs_events event, struct para_buffer *pb,
1126 void *data)
1127 {
1128 int i, ret;
1129
1130 for (i = 0; i < NUM_AFS_TABLES; i++) {
1131 struct afs_table *t = &afs_tables[i];
1132 if (!t->event_handler)
1133 continue;
1134 ret = t->event_handler(event, pb, data);
1135 if (ret < 0)
1136 PARA_CRIT_LOG("%s\n", PARA_STRERROR(-ret));
1137 }
1138 }
1139
1140 int images_event_handler(__a_unused enum afs_events event,
1141 __a_unused struct para_buffer *pb, __a_unused void *data)
1142 {
1143 return 1;
1144 }
1145
1146 int lyrics_event_handler(__a_unused enum afs_events event,
1147 __a_unused struct para_buffer *pb, __a_unused void *data)
1148 {
1149 return 1;
1150 }