2 * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file afs.c Paraslash's audio file selector. */
11 #include "server.cmdline.h"
16 #include <dirent.h> /* readdir() */
28 /** The osl tables used by afs. \sa blob.c. */
30 /** Contains audio file information. See aft.c. */
32 /** The table for the paraslash attributes. See attribute.c. */
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
42 * A standard blob table containing the mood definitions. For details
46 /** A blob table containing lyrics on a per-song basis. */
48 /** Another blob table for images (for example album cover art). */
50 /** Yet another blob table for storing standard playlists. */
52 /** How many tables are in use? */
56 static struct table_info afs_tables[NUM_AFS_TABLES];
59 /** The file descriptor for the local socket. */
62 * Value sent by the command handlers to identify themselves as
63 * children of the running para_server.
66 /** The associated task structure. */
71 * A random number used to "authenticate" the connection.
73 * para_server picks this number by random before forking the afs process. The
74 * command handlers write this number together with the id of the shared memory
75 * area containing the query. This way, a malicious local user has to know this
76 * number to be able to cause the afs process to crash by sending fake queries.
78 extern uint32_t afs_socket_cookie;
81 * Struct to let command handlers execute a callback in afs context.
83 * Commands that need to change the state of afs can't change the relevant data
84 * structures directly because commands are executed in a child process, i.e.
85 * they get their own virtual address space.
87 * This structure is used by \p send_callback_request() (executed from handler
88 * context) in order to let the afs process call the specified function. An
89 * instance of that structure is written to a shared memory area together with
90 * the arguments to the callback function. The identifier of the shared memory
91 * area is written to the command socket.
93 * The afs process accepts connections on the command socket and reads the
94 * shared memory id, attaches the corresponing area, calls the given handler to
95 * perform the desired action and to optionally compute a result.
97 * The result and a \p callback_result structure is then written to another
98 * shared memory area. The identifier for that area is written to the handler's
99 * command socket, so that the handler process can read the id, attach the
100 * shared memory area and use the result.
102 * \sa struct callback_result.
104 struct callback_query {
105 /** The function to be called. */
106 callback_function *handler;
107 /** The number of bytes of the query */
112 * Structure embedded in the result of a callback.
114 * If the callback produced a result, an instance of that structure is embeeded
115 * into the shared memory area holding the result, mainly to let the command
116 * handler know the size of the result.
118 * \sa struct callback_query.
120 struct callback_result {
121 /** The number of bytes of the result. */
126 * Ask the afs process to call a given function.
128 * \param f The function to be called.
129 * \param query Pointer to arbitrary data for the callback.
130 * \param result Callback result will be stored here.
132 * This function creates a shared memory area, copies the buffer pointed to by
133 * \a buf to that area and notifies the afs process that \a f should be
136 * \return Negative, on errors, the return value of the callback function
139 * \sa send_option_arg_callback_request(), send_standard_callback_request().
141 int send_callback_request(callback_function *f, struct osl_object *query,
142 struct osl_object *result)
144 struct callback_query *cq;
145 struct callback_result *cr;
146 int ret, fd = -1, query_shmid, result_shmid;
147 void *query_shm, *result_shm;
148 char buf[sizeof(afs_socket_cookie) + sizeof(int)];
149 struct sockaddr_un unix_addr;
150 size_t query_shm_size = sizeof(*cq);
153 query_shm_size += query->size;
154 ret = shm_new(query_shm_size);
158 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
163 cq->query_size = query_shm_size - sizeof(*cq);
166 memcpy(query_shm + sizeof(*cq), query->data, query->size);
167 ret = shm_detach(query_shm);
171 *(uint32_t *) buf = afs_socket_cookie;
172 *(int *) (buf + sizeof(afs_socket_cookie)) = query_shmid;
174 ret = get_stream_socket(PF_UNIX);
178 ret = init_unix_addr(&unix_addr, conf.afs_socket_arg);
181 ret = PARA_CONNECT(fd, &unix_addr);
184 ret = send_bin_buffer(fd, buf, sizeof(buf));
187 ret = recv_bin_buffer(fd, buf, sizeof(buf));
190 if (ret != sizeof(int)) {
198 ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
202 result->size = cr->result_size;
203 result->data = para_malloc(result->size);
204 memcpy(result->data, result_shm + sizeof(*cr), result->size);
205 ret = shm_detach(result_shm);
207 PARA_ERROR_LOG("can not detach result\n");
209 PARA_ERROR_LOG("attach result failed: %d\n", ret);
210 if (shm_destroy(result_shmid) < 0)
211 PARA_ERROR_LOG("destroy result failed\n");
214 if (shm_destroy(query_shmid) < 0)
215 PARA_ERROR_LOG("%s\n", "shm destroy error");
218 // PARA_DEBUG_LOG("callback_ret: %d\n", ret);
223 * Send a callback request passing an options structure and an argument vector.
225 * \param options pointer to an arbitrary data structure.
226 * \param argc Argument count.
227 * \param argv Standard argument vector.
228 * \param f The callback function.
229 * \param result The result of the query is stored here.
231 * Some commands have a couple of options that are parsed in child context for
232 * syntactic correctness and are stored in a special options structure for that
233 * command. This function allows to pass such a structure together with a list
234 * of further arguments (often a list of audio files) to the parent process.
236 * \sa send_standard_callback_request(), send_callback_request().
238 int send_option_arg_callback_request(struct osl_object *options,
239 int argc, char * const * const argv, callback_function *f,
240 struct osl_object *result)
244 struct osl_object query = {.size = options? options->size : 0};
246 for (i = 0; i < argc; i++)
247 query.size += strlen(argv[i]) + 1;
248 query.data = para_malloc(query.size);
251 memcpy(query.data, options->data, options->size);
254 for (i = 0; i < argc; i++) {
255 strcpy(p, argv[i]); /* OK */
256 p += strlen(argv[i]) + 1;
258 ret = send_callback_request(f, &query, result);
264 * Send a callback request with an argument vector only.
266 * \param argc The same meaning as in send_option_arg_callback_request().
267 * \param argv The same meaning as in send_option_arg_callback_request().
268 * \param f The same meaning as in send_option_arg_callback_request().
269 * \param result The same meaning as in send_option_arg_callback_request().
271 * This is similar to send_option_arg_callback_request(), but no options buffer
272 * is passed to the parent process.
274 * \return The return value of the underlying call to
275 * send_option_arg_callback_request().
277 int send_standard_callback_request(int argc, char * const * const argv,
278 callback_function *f, struct osl_object *result)
280 return send_option_arg_callback_request(NULL, argc, argv, f, result);
283 static int action_if_pattern_matches(struct osl_row *row, void *data)
285 struct pattern_match_data *pmd = data;
286 struct osl_object name_obj;
287 const char *p, *name;
288 int ret = osl_get_object(pmd->table, row, pmd->match_col_num, &name_obj);
289 const char *pattern_txt = (const char *)pmd->patterns.data;
293 name = (char *)name_obj.data;
294 if ((!name || !*name) && (pmd->pm_flags & PM_SKIP_EMPTY_NAME))
296 if (!pmd->patterns.size && (pmd->pm_flags & PM_NO_PATTERN_MATCHES_EVERYTHING))
297 return pmd->action(pmd->table, row, name, pmd->data);
298 for (p = pattern_txt; p < pattern_txt + pmd->patterns.size;
299 p += strlen(p) + 1) {
300 ret = fnmatch(p, name, pmd->fnmatch_flags);
301 if (ret == FNM_NOMATCH)
305 return pmd->action(pmd->table, row, name, pmd->data);
311 * Execute the given function for each matching row.
313 * \param pmd Describes what to match and how.
315 * \return The return value of the underlying call to osl_rbtree_loop()
316 * or osl_rbtree_loop_reverse().
318 int for_each_matching_row(struct pattern_match_data *pmd)
320 if (pmd->pm_flags & PM_REVERSE_LOOP)
321 return osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
322 action_if_pattern_matches);
323 return osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
324 action_if_pattern_matches);
328 * Compare two osl objects of string type.
330 * \param obj1 Pointer to the first object.
331 * \param obj2 Pointer to the second object.
333 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
334 * are taken into account.
336 * \return It returns an integer less than, equal to, or greater than zero if
337 * \a obj1 is found, respectively, to be less than, to match, or be greater than
340 * \sa strcmp(3), strncmp(3), osl_compare_func.
342 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
344 const char *str1 = (const char *)obj1->data;
345 const char *str2 = (const char *)obj2->data;
346 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
350 * write input from fd to dynamically allocated buffer,
351 * but maximal max_size byte.
353 static int fd2buf(int fd, unsigned max_size, struct osl_object *obj)
355 const size_t chunk_size = 1024;
356 size_t size = 2048, received = 0;
358 char *buf = para_malloc(size);
361 ret = recv_bin_buffer(fd, buf + received, chunk_size);
365 if (received + chunk_size >= size) {
367 ret = -E_INPUT_TOO_LARGE;
370 buf = para_realloc(buf, size);
374 obj->size = received;
381 * Read data from a file descriptor, and send it to the afs process.
383 * \param fd File descriptor to read data from.
384 * \param arg_obj Pointer to the arguments to \a f.
385 * \param f The callback function.
386 * \param max_len Don't read more than that many bytes from stdin.
387 * \param result The result of the query is stored here.
389 * This function is used by commands that wish to let para_server store
390 * arbitrary data specified by the user (for instance the add_blob family of
391 * commands). First, at most \a max_len bytes are read from \a fd, the result
392 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
393 * is made available to the parent process via shared memory.
395 * \return Negative on errors, the return value of the underlying call to
396 * send_callback_request() otherwise.
398 int stdin_command(int fd, struct osl_object *arg_obj, callback_function *f,
399 unsigned max_len, struct osl_object *result)
401 struct osl_object query, stdin_obj;
404 ret = send_buffer(fd, AWAITING_DATA_MSG);
407 ret = fd2buf(fd, max_len, &stdin_obj);
410 query.size = arg_obj->size + stdin_obj.size;
411 query.data = para_malloc(query.size);
412 memcpy(query.data, arg_obj->data, arg_obj->size);
413 memcpy((char *)query.data + arg_obj->size, stdin_obj.data, stdin_obj.size);
414 free(stdin_obj.data);
415 ret = send_callback_request(f, &query, result);
421 * Open the audio file with highest score.
423 * \param afd Audio file data is returned here.
425 * This stores all information for streaming the "best" audio file
426 * in the \a afd structure.
428 * \return Positive on success, negative on errors.
430 * \sa close_audio_file(), open_and_update_audio_file().
432 int open_next_audio_file(struct audio_file_data *afd)
434 struct osl_row *aft_row;
437 ret = score_get_best(&aft_row, &afd->score);
440 ret = open_and_update_audio_file(aft_row, afd);
447 * Free all resources which were allocated by open_next_audio_file().
449 * \param afd The structure previously filled in by open_next_audio_file().
451 * \return The return value of the underlying call to para_munmap().
453 * \sa open_next_audio_file().
455 int close_audio_file(struct audio_file_data *afd)
457 free(afd->afhi.chunk_table);
458 return para_munmap(afd->map.data, afd->map.size);
461 static enum play_mode init_admissible_files(void)
465 if (conf.mood_given) {
466 ret = change_current_mood(conf.mood_arg);
468 if (conf.playlist_given)
469 PARA_WARNING_LOG("ignoring playlist %s\n",
471 return PLAY_MODE_MOOD;
474 if (conf.playlist_given) {
475 ret = playlist_open(conf.playlist_arg);
477 return PLAY_MODE_PLAYLIST;
479 ret = change_current_mood(NULL); /* open first available mood */
481 return PLAY_MODE_MOOD;
482 change_current_mood(""); /* open dummy mood, always successful */
483 return PLAY_MODE_MOOD;
486 static int setup_command_socket_or_die(void)
489 char *socket_name = conf.afs_socket_arg;
490 struct sockaddr_un unix_addr;
493 ret = create_local_socket(socket_name, &unix_addr,
494 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
496 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
499 if (listen(ret , 5) < 0) {
500 PARA_EMERG_LOG("%s", "can not listen on socket\n");
503 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
508 static void close_afs_tables(enum osl_close_flags flags)
510 PARA_NOTICE_LOG("closing afs_tables\n");
511 score_shutdown(flags);
512 attribute_shutdown(flags);
513 close_current_mood();
515 moods_shutdown(flags);
516 playlists_shutdown(flags);
517 lyrics_shutdown(flags);
518 images_shutdown(flags);
522 static char *database_dir;
524 static int make_database_dir(void)
529 if (conf.afs_database_dir_given)
530 database_dir = para_strdup(conf.afs_database_dir_arg);
532 char *home = para_homedir();
533 database_dir = make_message(
534 "%s/.paraslash/afs_database", home);
538 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
539 ret = para_mkdir(database_dir, 0777);
540 if (ret >= 0 || is_errno(-ret, EEXIST))
548 static int open_afs_tables(void)
550 int ret = make_database_dir();
554 ret = attribute_init(&afs_tables[TBLNUM_ATTRIBUTES], database_dir);
557 ret = moods_init(&afs_tables[TBLNUM_MOODS], database_dir);
559 goto moods_init_error;
560 ret = playlists_init(&afs_tables[TBLNUM_PLAYLIST], database_dir);
562 goto playlists_init_error;
563 ret = lyrics_init(&afs_tables[TBLNUM_LYRICS], database_dir);
565 goto lyrics_init_error;
566 ret = images_init(&afs_tables[TBLNUM_IMAGES], database_dir);
568 goto images_init_error;
569 ret = score_init(&afs_tables[TBLNUM_SCORES], database_dir);
571 goto score_init_error;
572 ret = aft_init(&afs_tables[TBLNUM_AUDIO_FILES], database_dir);
578 score_shutdown(OSL_MARK_CLEAN);
580 images_shutdown(OSL_MARK_CLEAN);
582 lyrics_shutdown(OSL_MARK_CLEAN);
584 playlists_shutdown(OSL_MARK_CLEAN);
585 playlists_init_error:
586 moods_shutdown(OSL_MARK_CLEAN);
588 attribute_shutdown(OSL_MARK_CLEAN);
592 static int server_socket;
593 static struct command_task command_task_struct;
594 static struct signal_task signal_task_struct;
596 static void unregister_tasks(void)
598 unregister_task(&command_task_struct.task);
599 unregister_task(&signal_task_struct.task);
602 static void signal_pre_select(struct sched *s, struct task *t)
604 struct signal_task *st = t->private_data;
606 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
609 static void signal_post_select(struct sched *s, struct task *t)
611 struct signal_task *st = t->private_data;
613 if (!FD_ISSET(st->fd, &s->rfds))
615 st->signum = para_next_signal();
617 if (st->signum == SIGUSR1)
618 return; /* ignore SIGUSR1 */
619 if (st->signum == SIGHUP) {
620 close_afs_tables(OSL_MARK_CLEAN);
621 t->ret = open_afs_tables();
624 PARA_NOTICE_LOG("caught signal %d\n", st->signum);
625 t->ret = -E_AFS_SIGNAL;
629 static void register_signal_task(void)
631 struct signal_task *st = &signal_task_struct;
632 st->fd = para_signal_init();
633 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
634 para_install_sighandler(SIGINT);
635 para_install_sighandler(SIGTERM);
636 para_install_sighandler(SIGPIPE);
637 para_install_sighandler(SIGHUP);
639 st->task.pre_select = signal_pre_select;
640 st->task.post_select = signal_post_select;
641 st->task.private_data = st;
642 sprintf(st->task.status, "signal task");
643 register_task(&st->task);
646 static struct list_head afs_client_list;
649 struct list_head node;
651 struct timeval connect_time;
654 static void command_pre_select(struct sched *s, struct task *t)
656 struct command_task *ct = t->private_data;
657 struct afs_client *client;
659 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
660 list_for_each_entry(client, &afs_client_list, node)
661 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
666 * On errors, negative value is written to fd.
667 * On success: If query produced a result, the result_shmid is written to fd.
668 * Otherwise, zero is written.
670 static int call_callback(int fd, int query_shmid)
672 void *query_shm, *result_shm;
673 struct callback_query *cq;
674 struct callback_result *cr;
675 struct osl_object query, result = {.data = NULL};
676 int result_shmid = -1, ret, ret2;
678 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
682 query.data = (char *)query_shm + sizeof(*cq);
683 query.size = cq->query_size;
684 ret = cq->handler(&query, &result);
685 ret2 = shm_detach(query_shm);
686 if (ret2 < 0 && ret >= 0)
691 if (!result.data || !result.size)
693 ret = shm_new(result.size + sizeof(struct callback_result));
697 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
701 cr->result_size = result.size;
702 memcpy(result_shm + sizeof(*cr), result.data, result.size);
703 ret = shm_detach(result_shm);
709 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
710 if (ret < 0 || ret2 < 0) {
711 if (result_shmid >= 0)
712 if (shm_destroy(result_shmid) < 0)
713 PARA_ERROR_LOG("destroy result failed\n");
720 static void execute_afs_command(int fd, uint32_t expected_cookie)
724 char buf[sizeof(cookie) + sizeof(query_shmid)];
725 int ret = recv_bin_buffer(fd, buf, sizeof(buf));
728 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
731 if (ret != sizeof(buf)) {
732 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
733 ret, (long unsigned) sizeof(buf));
736 cookie = *(uint32_t *)buf;
737 if (cookie != expected_cookie) {
738 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
739 (unsigned)cookie, (unsigned)expected_cookie);
742 query_shmid = *(int *)(buf + sizeof(cookie));
743 if (query_shmid < 0) {
744 PARA_WARNING_LOG("received invalid query shmid %d)\n",
748 /* Ignore return value: Errors might be OK here. */
749 call_callback(fd, query_shmid);
752 /** Shutdown connection if query has not arrived until this many seconds. */
753 #define AFS_CLIENT_TIMEOUT 3
755 static void command_post_select(struct sched *s, struct task *t)
757 struct command_task *ct = t->private_data;
758 struct sockaddr_un unix_addr;
759 struct afs_client *client, *tmp;
761 /* First, check the list of connected clients. */
762 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
763 if (FD_ISSET(client->fd, &s->rfds))
764 execute_afs_command(client->fd, ct->cookie);
765 else { /* prevent bogus connection flooding */
767 tv_diff(now, &client->connect_time, &diff);
768 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
770 PARA_WARNING_LOG("connection timeout\n");
773 list_del(&client->node);
776 /* Next, accept connections on the local socket. */
777 if (!FD_ISSET(ct->fd, &s->rfds))
779 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
781 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
784 client = para_malloc(sizeof(*client));
786 client->connect_time = *now;
787 para_list_add(&client->node, &afs_client_list);
792 static void register_command_task(uint32_t cookie)
794 struct command_task *ct = &command_task_struct;
795 ct->fd = setup_command_socket_or_die();
798 ct->task.pre_select = command_pre_select;
799 ct->task.post_select = command_post_select;
800 ct->task.private_data = ct;
801 sprintf(ct->task.status, "command task");
802 register_task(&ct->task);
805 static void register_tasks(uint32_t cookie)
807 register_signal_task();
808 register_command_task(cookie);
812 * Initialize the audio file selector process.
814 * \param cookie The value used for "authentication".
815 * \param socket_fd File descriptor used for communication with the server.
817 __noreturn void afs_init(uint32_t cookie, int socket_fd)
819 enum play_mode current_play_mode;
823 INIT_LIST_HEAD(&afs_client_list);
824 ret = open_afs_tables();
827 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
830 server_socket = socket_fd;
831 ret = mark_fd_nonblock(server_socket);
834 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
835 server_socket, (unsigned) cookie);
836 current_play_mode = init_admissible_files();
837 register_tasks(cookie);
838 s.default_timeout.tv_sec = 0;
839 s.default_timeout.tv_usec = 99 * 1000;
842 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
843 close_afs_tables(OSL_MARK_CLEAN);
847 static int create_tables_callback(const struct osl_object *query,
848 __a_unused struct osl_object *result)
850 uint32_t table_mask = *(uint32_t *)query->data;
853 close_afs_tables(OSL_MARK_CLEAN);
854 for (i = 0; i < NUM_AFS_TABLES; i++) {
855 struct table_info *ti = afs_tables + i;
857 if (ti->flags & TBLFLAG_SKIP_CREATE)
859 if (!(table_mask & (1 << i)))
861 ret = osl_create_table(ti->desc);
865 ret = open_afs_tables();
866 return ret < 0? ret: 0;
869 int com_init(int fd, int argc, char * const * const argv)
872 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
873 struct osl_object query = {.data = &table_mask,
874 .size = sizeof(table_mask)};
878 for (i = 1; i < argc; i++) {
879 for (j = 0; j < NUM_AFS_TABLES; j++) {
880 struct table_info *ti = afs_tables + j;
882 if (ti->flags & TBLFLAG_SKIP_CREATE)
884 if (strcmp(argv[i], ti->desc->name))
886 table_mask |= (1 << j);
889 if (j == NUM_AFS_TABLES)
890 return -E_BAD_TABLE_NAME;
893 ret = send_callback_request(create_tables_callback, &query, NULL);
896 return send_va_buffer(fd, "successfully created afs table(s)\n");
900 * Flags for the check command.
904 enum com_check_flags {
905 /** Check the audio file table. */
907 /** Check the mood table. */
909 /** Check the playlist table. */
913 int com_check(int fd, int argc, char * const * const argv)
917 struct osl_object result;
919 for (i = 1; i < argc; i++) {
920 const char *arg = argv[i];
923 if (!strcmp(arg, "--")) {
927 if (!strcmp(arg, "-a")) {
931 if (!strcmp(arg, "-p")) {
932 flags |= CHECK_PLAYLISTS;
935 if (!strcmp(arg, "-m")) {
936 flags |= CHECK_MOODS;
939 return -E_AFS_SYNTAX;
942 return -E_AFS_SYNTAX;
945 if (flags & CHECK_AFT) {
946 ret = send_callback_request(aft_check_callback, NULL, &result);
950 ret = send_buffer(fd, (char *) result.data);
956 if (flags & CHECK_PLAYLISTS) {
957 ret = send_callback_request(playlist_check_callback, NULL, &result);
961 ret = send_buffer(fd, (char *) result.data);
967 if (flags & CHECK_MOODS) {
968 ret = send_callback_request(mood_check_callback, NULL, &result);
972 ret = send_buffer(fd, (char *) result.data);