b9243a4169b16addf95a010ba580ea8170acd24c
[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 long score;
490 again:
491 PARA_NOTICE_LOG("getting next audio file\n");
492 ret = score_get_best(&aft_row, &score);
493 if (ret < 0) {
494 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
495 goto no_admissible_files;
496 }
497 ret = open_and_update_audio_file(aft_row, score, &afd);
498 if (ret < 0) {
499 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
500 ret = score_delete(aft_row);
501 if (ret < 0) {
502 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
503 goto no_admissible_files;
504 }
505 goto again;
506 }
507 shmid = ret;
508 if (!write_ok(server_socket)) {
509 ret = -E_AFS_SOCKET;
510 goto destroy;
511 }
512 *(uint32_t *)buf = NEXT_AUDIO_FILE;
513 *(uint32_t *)(buf + 4) = (uint32_t)shmid;
514 ret = pass_afd(afd.fd, buf, 8);
515 close(afd.fd);
516 if (ret >= 0)
517 return ret;
518 destroy:
519 shm_destroy(shmid);
520 return ret;
521 no_admissible_files:
522 *(uint32_t *)buf = NO_ADMISSIBLE_FILES;
523 *(uint32_t *)(buf + 4) = (uint32_t)0;
524 return send_bin_buffer(server_socket, buf, 8);
525 }
526
527 /* Never fails if arg == NULL */
528 static int activate_mood_or_playlist(char *arg, int *num_admissible)
529 {
530 enum play_mode mode;
531 int ret;
532
533 if (!arg) {
534 ret = change_current_mood(NULL); /* always successful */
535 mode = PLAY_MODE_MOOD;
536 } else {
537 if (!strncmp(arg, "p:", 2)) {
538 ret = playlist_open(arg + 2);
539 mode = PLAY_MODE_PLAYLIST;
540 } else if (!strncmp(arg, "m:", 2)) {
541 ret = change_current_mood(arg + 2);
542 mode = PLAY_MODE_MOOD;
543 } else
544 return -E_AFS_SYNTAX;
545 if (ret < 0)
546 return ret;
547 }
548 if (num_admissible)
549 *num_admissible = ret;
550 current_play_mode = mode;
551 if (arg != current_mop) {
552 free(current_mop);
553 if (arg) {
554 current_mop = para_strdup(arg);
555 mmd_lock();
556 strncpy(mmd->afs_mode_string, arg,
557 sizeof(mmd->afs_mode_string));
558 mmd->afs_mode_string[sizeof(mmd->afs_mode_string) - 1] = '\0';
559 mmd_unlock();
560 } else {
561 mmd_lock();
562 strcpy(mmd->afs_mode_string, "dummy");
563 mmd_unlock();
564 current_mop = NULL;
565 }
566 }
567 return 1;
568 }
569
570 static int com_select_callback(const struct osl_object *query,
571 struct osl_object *result)
572 {
573 struct para_buffer pb = {.buf = NULL};
574 char *arg = query->data;
575 int num_admissible, ret;
576
577 ret = clear_score_table();
578 if (ret < 0)
579 return ret;
580 if (current_play_mode == PLAY_MODE_MOOD)
581 close_current_mood();
582 else
583 playlist_close();
584 ret = activate_mood_or_playlist(arg, &num_admissible);
585 if (ret < 0) {
586 para_printf(&pb, "%s\n", PARA_STRERROR(-ret));
587 para_printf(&pb, "switching back to %s\n", current_mop?
588 current_mop : "dummy");
589 ret = activate_mood_or_playlist(current_mop, &num_admissible);
590 if (ret < 0) {
591 para_printf(&pb, "failed, switching to dummy\n");
592 activate_mood_or_playlist(NULL, &num_admissible);
593 }
594 }
595 para_printf(&pb, "activated %s (%d admissible files)\n", current_mop?
596 current_mop : "dummy mood", num_admissible);
597 result->data = pb.buf;
598 result->size = pb.size;
599 return 1;
600 }
601
602 int com_select(int fd, int argc, char * const * const argv)
603 {
604 int ret;
605 struct osl_object query, result;
606
607 if (argc != 2)
608 return -E_AFS_SYNTAX;
609 query.data = argv[1];
610 query.size = strlen(argv[1]) + 1;
611 ret = send_callback_request(com_select_callback, &query,
612 &result);
613 if (ret > 0 && result.data && result.size) {
614 ret = send_va_buffer(fd, "%s", (char *)result.data);
615 free(result.data);
616 }
617 return ret;
618 }
619
620 static void init_admissible_files(char *arg)
621 {
622 if (activate_mood_or_playlist(arg, NULL) < 0)
623 activate_mood_or_playlist(NULL, NULL); /* always successful */
624 }
625
626 static int setup_command_socket_or_die(void)
627 {
628 int ret, socket_fd;
629 char *socket_name = conf.afs_socket_arg;
630 struct sockaddr_un unix_addr;
631
632 unlink(socket_name);
633 ret = create_local_socket(socket_name, &unix_addr,
634 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
635 if (ret < 0) {
636 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
637 exit(EXIT_FAILURE);
638 }
639 socket_fd = ret;
640 if (listen(socket_fd , 5) < 0) {
641 PARA_EMERG_LOG("can not listen on socket\n");
642 exit(EXIT_FAILURE);
643 }
644 ret = mark_fd_nonblock(socket_fd);
645 if (ret < 0) {
646 close(socket_fd);
647 return ret;
648 }
649 PARA_INFO_LOG("listening on socket %s (fd %d)\n", socket_name, ret);
650 return socket_fd;
651 }
652
653 static void close_afs_tables(void)
654 {
655 int i;
656 PARA_NOTICE_LOG("closing afs_tables\n");
657 for (i = 0; i < NUM_AFS_TABLES; i++)
658 afs_tables[i].close();
659 }
660
661 static char *database_dir;
662
663 static void get_database_dir(void)
664 {
665 if (!database_dir) {
666 if (conf.afs_database_dir_given)
667 database_dir = para_strdup(conf.afs_database_dir_arg);
668 else {
669 char *home = para_homedir();
670 database_dir = make_message(
671 "%s/.paraslash/afs_database", home);
672 free(home);
673 }
674 }
675 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
676 }
677
678 static int make_database_dir(void)
679 {
680 int ret;
681
682 get_database_dir();
683 ret = para_mkdir(database_dir, 0777);
684 if (ret >= 0 || is_errno(-ret, EEXIST))
685 return 1;
686 return ret;
687 }
688
689 static int open_afs_tables(void)
690 {
691 int i, ret;
692
693 get_database_dir();
694 PARA_NOTICE_LOG("opening %u osl tables in %s\n", NUM_AFS_TABLES,
695 database_dir);
696 for (i = 0; i < NUM_AFS_TABLES; i++) {
697 ret = afs_tables[i].open(database_dir);
698 if (ret >= 0)
699 continue;
700 PARA_ERROR_LOG("%s init: %s\n", afs_tables[i].name,
701 PARA_STRERROR(-ret));
702 break;
703 }
704 if (ret >= 0)
705 return ret;
706 while (i)
707 afs_tables[--i].close();
708 return ret;
709 }
710
711 static void unregister_tasks(void)
712 {
713 unregister_task(&command_task_struct.task);
714 unregister_task(&signal_task_struct.task);
715 }
716
717 static void signal_pre_select(struct sched *s, struct task *t)
718 {
719 struct signal_task *st = t->private_data;
720 t->ret = 1;
721 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
722 }
723
724 static void signal_post_select(struct sched *s, struct task *t)
725 {
726 struct signal_task *st = t->private_data;
727 t->ret = -E_AFS_PARENT_DIED;
728 if (getppid() == 1)
729 goto err;
730 t->ret = 1;
731 if (!FD_ISSET(st->fd, &s->rfds))
732 return;
733 st->signum = para_next_signal();
734 t->ret = 1;
735 if (st->signum == SIGUSR1)
736 return; /* ignore SIGUSR1 */
737 if (st->signum == SIGHUP) {
738 close_afs_tables();
739 t->ret = open_afs_tables();
740 if (t->ret < 0)
741 goto err;
742 init_admissible_files(current_mop);
743 return;
744 }
745 t->ret = -E_AFS_SIGNAL;
746 err:
747 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
748 unregister_tasks();
749 }
750
751 static void register_signal_task(void)
752 {
753 struct signal_task *st = &signal_task_struct;
754 st->fd = para_signal_init();
755 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
756 para_install_sighandler(SIGINT);
757 para_install_sighandler(SIGTERM);
758 para_install_sighandler(SIGPIPE);
759 para_install_sighandler(SIGHUP);
760
761 st->task.pre_select = signal_pre_select;
762 st->task.post_select = signal_post_select;
763 st->task.private_data = st;
764 sprintf(st->task.status, "signal task");
765 register_task(&st->task);
766 }
767
768 static struct list_head afs_client_list;
769
770 /** Describes on connected afs client. */
771 struct afs_client {
772 /** Position in the afs client list. */
773 struct list_head node;
774 /** The socket file descriptor for this client. */
775 int fd;
776 /** The time the client connected. */
777 struct timeval connect_time;
778 };
779
780 static void command_pre_select(struct sched *s, struct task *t)
781 {
782 struct command_task *ct = t->private_data;
783 struct afs_client *client;
784
785 para_fd_set(server_socket, &s->rfds, &s->max_fileno);
786 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
787 list_for_each_entry(client, &afs_client_list, node)
788 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
789 t->ret = 1;
790 }
791
792 /*
793 * On errors, negative value is written to fd.
794 * On success: If query produced a result, the result_shmid is written to fd.
795 * Otherwise, zero is written.
796 */
797 static int call_callback(int fd, int query_shmid)
798 {
799 void *query_shm, *result_shm;
800 struct callback_query *cq;
801 struct callback_result *cr;
802 struct osl_object query, result = {.data = NULL};
803 int result_shmid = -1, ret, ret2;
804
805 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
806 if (ret < 0)
807 goto out;
808 cq = query_shm;
809 query.data = (char *)query_shm + sizeof(*cq);
810 query.size = cq->query_size;
811 ret = cq->handler(&query, &result);
812 ret2 = shm_detach(query_shm);
813 if (ret2 < 0 && ret >= 0)
814 ret = ret2;
815 if (ret < 0)
816 goto out;
817 ret = 0;
818 if (!result.data || !result.size)
819 goto out;
820 ret = shm_new(result.size + sizeof(struct callback_result));
821 if (ret < 0)
822 goto out;
823 result_shmid = ret;
824 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
825 if (ret < 0)
826 goto out;
827 cr = result_shm;
828 cr->result_size = result.size;
829 memcpy(result_shm + sizeof(*cr), result.data, result.size);
830 ret = shm_detach(result_shm);
831 if (ret < 0)
832 goto out;
833 ret = result_shmid;
834 out:
835 free(result.data);
836 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
837 if (ret < 0 || ret2 < 0) {
838 if (result_shmid >= 0)
839 if (shm_destroy(result_shmid) < 0)
840 PARA_ERROR_LOG("destroy result failed\n");
841 if (ret >= 0)
842 ret = ret2;
843 }
844 return ret;
845 }
846
847 static void execute_server_command(void)
848 {
849 char buf[8];
850 int ret = recv_bin_buffer(server_socket, buf, sizeof(buf) - 1);
851
852 if (ret <= 0) {
853 if (ret < 0)
854 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
855 return;
856 }
857 buf[ret] = '\0';
858 PARA_DEBUG_LOG("received: %s\n", buf);
859 if (!strcmp(buf, "new")) {
860 ret = open_next_audio_file();
861 if (ret < 0) {
862 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
863 unregister_tasks();
864 }
865 return;
866 }
867 PARA_ERROR_LOG("unknown command\n");
868
869 }
870
871 static void execute_afs_command(int fd, uint32_t expected_cookie)
872 {
873 uint32_t cookie;
874 int query_shmid;
875 char buf[sizeof(cookie) + sizeof(query_shmid)];
876 int ret = recv_bin_buffer(fd, buf, sizeof(buf));
877
878 if (ret < 0) {
879 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
880 return;
881 }
882 if (ret != sizeof(buf)) {
883 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
884 ret, (long unsigned) sizeof(buf));
885 return;
886 }
887 cookie = *(uint32_t *)buf;
888 if (cookie != expected_cookie) {
889 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
890 (unsigned)cookie, (unsigned)expected_cookie);
891 return;
892 }
893 query_shmid = *(int *)(buf + sizeof(cookie));
894 if (query_shmid < 0) {
895 PARA_WARNING_LOG("received invalid query shmid %d)\n",
896 query_shmid);
897 return;
898 }
899 /* Ignore return value: Errors might be OK here. */
900 call_callback(fd, query_shmid);
901 }
902
903 /** Shutdown connection if query has not arrived until this many seconds. */
904 #define AFS_CLIENT_TIMEOUT 3
905
906 static void command_post_select(struct sched *s, struct task *t)
907 {
908 struct command_task *ct = t->private_data;
909 struct sockaddr_un unix_addr;
910 struct afs_client *client, *tmp;
911 int fd;
912 if (FD_ISSET(server_socket, &s->rfds))
913 execute_server_command();
914
915 /* Check the list of connected clients. */
916 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
917 if (FD_ISSET(client->fd, &s->rfds))
918 execute_afs_command(client->fd, ct->cookie);
919 else { /* prevent bogus connection flooding */
920 struct timeval diff;
921 tv_diff(now, &client->connect_time, &diff);
922 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
923 continue;
924 PARA_WARNING_LOG("connection timeout\n");
925 }
926 close(client->fd);
927 list_del(&client->node);
928 free(client);
929 }
930 /* Accept connections on the local socket. */
931 if (!FD_ISSET(ct->fd, &s->rfds))
932 goto out;
933 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
934 if (t->ret < 0) {
935 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
936 goto out;
937 }
938 fd = t->ret;
939 t->ret = mark_fd_nonblock(fd);
940 if (t->ret < 0) {
941 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
942 close(fd);
943 goto out;
944 }
945 client = para_malloc(sizeof(*client));
946 client->fd = fd;
947 client->connect_time = *now;
948 para_list_add(&client->node, &afs_client_list);
949 out:
950 t->ret = 1;
951 }
952
953 static void register_command_task(uint32_t cookie)
954 {
955 struct command_task *ct = &command_task_struct;
956 ct->fd = setup_command_socket_or_die();
957 ct->cookie = cookie;
958
959 ct->task.pre_select = command_pre_select;
960 ct->task.post_select = command_post_select;
961 ct->task.private_data = ct;
962 sprintf(ct->task.status, "command task");
963 register_task(&ct->task);
964 }
965
966 static void register_tasks(uint32_t cookie)
967 {
968 register_signal_task();
969 register_command_task(cookie);
970 }
971
972 /**
973 * Initialize the audio file selector process.
974 *
975 * \param cookie The value used for "authentication".
976 * \param socket_fd File descriptor used for communication with the server.
977 */
978 __noreturn void afs_init(uint32_t cookie, int socket_fd)
979 {
980 struct sched s;
981 int i, ret;
982
983 INIT_LIST_HEAD(&afs_client_list);
984 for (i = 0; i < NUM_AFS_TABLES; i++)
985 afs_tables[i].init(&afs_tables[i]);
986 ret = open_afs_tables();
987
988 if (ret < 0) {
989 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
990 exit(EXIT_FAILURE);
991 }
992 server_socket = socket_fd;
993 ret = mark_fd_nonblock(server_socket);
994 if (ret < 0)
995 exit(EXIT_FAILURE);
996 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
997 server_socket, (unsigned) cookie);
998 init_admissible_files(conf.afs_initial_mode_arg);
999 register_tasks(cookie);
1000 s.default_timeout.tv_sec = 0;
1001 s.default_timeout.tv_usec = 999 * 1000;
1002 ret = schedule(&s);
1003 if (ret < 0)
1004 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
1005 close_afs_tables();
1006 exit(EXIT_FAILURE);
1007 }
1008
1009 static int create_tables_callback(const struct osl_object *query,
1010 __a_unused struct osl_object *result)
1011 {
1012 uint32_t table_mask = *(uint32_t *)query->data;
1013 int i, ret;
1014
1015 close_afs_tables();
1016 for (i = 0; i < NUM_AFS_TABLES; i++) {
1017 struct afs_table *t = &afs_tables[i];
1018
1019 if (!(table_mask & (1 << i)))
1020 continue;
1021 if (!t->create)
1022 continue;
1023 ret = t->create(database_dir);
1024 if (ret < 0)
1025 return ret;
1026 }
1027 ret = open_afs_tables();
1028 return ret < 0? ret: 0;
1029 }
1030
1031 int com_init(int fd, int argc, char * const * const argv)
1032 {
1033 int i, j, ret;
1034 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
1035 struct osl_object query = {.data = &table_mask,
1036 .size = sizeof(table_mask)};
1037
1038 ret = make_database_dir();
1039 if (ret < 0)
1040 return ret;
1041 if (argc != 1) {
1042 table_mask = 0;
1043 for (i = 1; i < argc; i++) {
1044 for (j = 0; j < NUM_AFS_TABLES; j++) {
1045 struct afs_table *t = &afs_tables[j];
1046
1047 if (strcmp(argv[i], t->name))
1048 continue;
1049 table_mask |= (1 << j);
1050 break;
1051 }
1052 if (j == NUM_AFS_TABLES)
1053 return -E_BAD_TABLE_NAME;
1054 }
1055 }
1056 ret = send_callback_request(create_tables_callback, &query, NULL);
1057 if (ret < 0)
1058 return ret;
1059 return send_va_buffer(fd, "successfully created afs table(s)\n");
1060 }
1061
1062 /**
1063 * Flags for the check command.
1064 *
1065 * \sa com_check().
1066 */
1067 enum com_check_flags {
1068 /** Check the audio file table. */
1069 CHECK_AFT = 1,
1070 /** Check the mood table. */
1071 CHECK_MOODS = 2,
1072 /** Check the playlist table. */
1073 CHECK_PLAYLISTS = 4
1074 };
1075
1076 int com_check(int fd, int argc, char * const * const argv)
1077 {
1078 unsigned flags = 0;
1079 int i, ret;
1080 struct osl_object result;
1081
1082 for (i = 1; i < argc; i++) {
1083 const char *arg = argv[i];
1084 if (arg[0] != '-')
1085 break;
1086 if (!strcmp(arg, "--")) {
1087 i++;
1088 break;
1089 }
1090 if (!strcmp(arg, "-a")) {
1091 flags |= CHECK_AFT;
1092 continue;
1093 }
1094 if (!strcmp(arg, "-p")) {
1095 flags |= CHECK_PLAYLISTS;
1096 continue;
1097 }
1098 if (!strcmp(arg, "-m")) {
1099 flags |= CHECK_MOODS;
1100 continue;
1101 }
1102 return -E_AFS_SYNTAX;
1103 }
1104 if (i < argc)
1105 return -E_AFS_SYNTAX;
1106 if (!flags)
1107 flags = ~0U;
1108 if (flags & CHECK_AFT) {
1109 ret = send_callback_request(aft_check_callback, NULL, &result);
1110 if (ret < 0)
1111 return ret;
1112 if (ret > 0) {
1113 ret = send_buffer(fd, (char *) result.data);
1114 free(result.data);
1115 if (ret < 0)
1116 return ret;
1117 }
1118 }
1119 if (flags & CHECK_PLAYLISTS) {
1120 ret = send_callback_request(playlist_check_callback, NULL, &result);
1121 if (ret < 0)
1122 return ret;
1123 if (ret > 0) {
1124 ret = send_buffer(fd, (char *) result.data);
1125 free(result.data);
1126 if (ret < 0)
1127 return ret;
1128 }
1129 }
1130 if (flags & CHECK_MOODS) {
1131 ret = send_callback_request(mood_check_callback, NULL, &result);
1132 if (ret < 0)
1133 return ret;
1134 if (ret > 0) {
1135 ret = send_buffer(fd, (char *) result.data);
1136 free(result.data);
1137 if (ret < 0)
1138 return ret;
1139 }
1140 }
1141 return 1;
1142 }
1143
1144 void afs_event(enum afs_events event, struct para_buffer *pb,
1145 void *data)
1146 {
1147 int i, ret;
1148
1149 for (i = 0; i < NUM_AFS_TABLES; i++) {
1150 struct afs_table *t = &afs_tables[i];
1151 if (!t->event_handler)
1152 continue;
1153 ret = t->event_handler(event, pb, data);
1154 if (ret < 0)
1155 PARA_CRIT_LOG("%s\n", PARA_STRERROR(-ret));
1156 }
1157 }
1158
1159 int images_event_handler(__a_unused enum afs_events event,
1160 __a_unused struct para_buffer *pb, __a_unused void *data)
1161 {
1162 return 1;
1163 }
1164
1165 int lyrics_event_handler(__a_unused enum afs_events event,
1166 __a_unused struct para_buffer *pb, __a_unused void *data)
1167 {
1168 return 1;
1169 }