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 parent 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);
310 int for_each_matching_row(struct pattern_match_data *pmd)
312 if (pmd->pm_flags & PM_REVERSE_LOOP)
313 return osl_rbtree_loop_reverse(pmd->table, pmd->loop_col_num, pmd,
314 action_if_pattern_matches);
315 return osl_rbtree_loop(pmd->table, pmd->loop_col_num, pmd,
316 action_if_pattern_matches);
320 * Compare two osl objects of string type.
322 * \param obj1 Pointer to the first object.
323 * \param obj2 Pointer to the second object.
325 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
326 * are taken into account.
328 * \return It returns an integer less than, equal to, or greater than zero if
329 * \a obj1 is found, respectively, to be less than, to match, or be greater than
332 * \sa strcmp(3), strncmp(3), osl_compare_func.
334 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
336 const char *str1 = (const char *)obj1->data;
337 const char *str2 = (const char *)obj2->data;
338 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
342 * write input from fd to dynamically allocated buffer,
343 * but maximal max_size byte.
345 static int fd2buf(int fd, unsigned max_size, struct osl_object *obj)
347 const size_t chunk_size = 1024;
348 size_t size = 2048, received = 0;
350 char *buf = para_malloc(size);
353 ret = recv_bin_buffer(fd, buf + received, chunk_size);
357 if (received + chunk_size >= size) {
359 ret = -E_INPUT_TOO_LARGE;
362 buf = para_realloc(buf, size);
366 obj->size = received;
373 * Read data from a file descriptor, and send it to the afs process.
375 * \param fd File descriptor to read data from.
376 * \param arg_obj Pointer to the arguments to \a f.
377 * \param f The callback function.
378 * \param max_len Don't read more than that many bytes from stdin.
379 * \param result The result of the query is stored here.
381 * This function is used by commands that wish to let para_server store
382 * arbitrary data specified by the user (for instance the add_blob family of
383 * commands). First, at most \a max_len bytes are read from \a fd, the result
384 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
385 * is made available to the parent process via shared memory.
387 * \return Negative on errors, the return value of the underlying call to
388 * send_callback_request() otherwise.
390 int stdin_command(int fd, struct osl_object *arg_obj, callback_function *f,
391 unsigned max_len, struct osl_object *result)
393 struct osl_object query, stdin_obj;
396 ret = send_buffer(fd, AWAITING_DATA_MSG);
399 ret = fd2buf(fd, max_len, &stdin_obj);
402 query.size = arg_obj->size + stdin_obj.size;
403 query.data = para_malloc(query.size);
404 memcpy(query.data, arg_obj->data, arg_obj->size);
405 memcpy((char *)query.data + arg_obj->size, stdin_obj.data, stdin_obj.size);
406 free(stdin_obj.data);
407 ret = send_callback_request(f, &query, result);
413 * Open the audio file with highest score.
415 * \param afd Audio file data is returned here.
417 * This stores all information for streaming the "best" audio file
418 * in the \a afd structure.
420 * \return Positive on success, negative on errors.
422 * \sa close_audio_file(), open_and_update_audio_file().
424 int open_next_audio_file(struct audio_file_data *afd)
426 struct osl_row *aft_row;
429 ret = score_get_best(&aft_row, &afd->score);
432 ret = open_and_update_audio_file(aft_row, afd);
439 * Free all resources which were allocated by open_next_audio_file().
441 * \param afd The structure previously filled in by open_next_audio_file().
443 * \return The return value of the underlying call to para_munmap().
445 * \sa open_next_audio_file().
447 int close_audio_file(struct audio_file_data *afd)
449 free(afd->afhi.chunk_table);
450 return para_munmap(afd->map.data, afd->map.size);
454 static void play_loop(enum play_mode current_play_mode)
457 struct audio_file_data afd;
459 afd.current_play_mode = current_play_mode;
460 for (i = 0; i < 0; i++) {
461 ret = open_next_audio_file(&afd);
463 PARA_ERROR_LOG("failed to open next audio file: %d\n", ret);
466 PARA_NOTICE_LOG("next audio file: %s, score: %li\n", afd.path, afd.score);
468 close_audio_file(&afd);
474 static enum play_mode init_admissible_files(void)
477 char *given_mood, *given_playlist;
479 given_mood = "mood_that_was_given_at_the_command_line";
480 given_playlist = "given_playlist";
483 ret = change_current_mood(given_mood);
486 PARA_WARNING_LOG("ignoring playlist %s\n",
488 return PLAY_MODE_MOOD;
491 if (given_playlist) {
492 ret = playlist_open(given_playlist);
494 return PLAY_MODE_PLAYLIST;
496 ret = change_current_mood(NULL); /* open first available mood */
498 return PLAY_MODE_MOOD;
499 change_current_mood(""); /* open dummy mood, always successful */
500 return PLAY_MODE_MOOD;
503 static int setup_command_socket_or_die(void)
506 char *socket_name = conf.afs_socket_arg;
507 struct sockaddr_un unix_addr;
510 ret = create_local_socket(socket_name, &unix_addr,
511 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
513 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
516 if (listen(ret , 5) < 0) {
517 PARA_EMERG_LOG("%s", "can not listen on socket\n");
520 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
525 static int server_socket;
526 static struct command_task command_task_struct;
527 static struct signal_task signal_task_struct;
529 static void unregister_tasks(void)
531 unregister_task(&command_task_struct.task);
532 unregister_task(&signal_task_struct.task);
535 static void close_afs_tables(enum osl_close_flags flags)
537 PARA_NOTICE_LOG("closing afs_tables\n");
538 score_shutdown(flags);
539 attribute_shutdown(flags);
540 close_current_mood();
542 moods_shutdown(flags);
543 playlists_shutdown(flags);
544 lyrics_shutdown(flags);
545 images_shutdown(flags);
549 static void signal_pre_select(struct sched *s, struct task *t)
551 struct signal_task *st = t->private_data;
553 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
556 static void signal_post_select(struct sched *s, struct task *t)
558 struct signal_task *st = t->private_data;
560 if (!FD_ISSET(st->fd, &s->rfds))
562 st->signum = para_next_signal();
564 if (st->signum == SIGUSR1)
565 return; /* ignore SIGUSR1 */
566 PARA_NOTICE_LOG("caught signal %d\n", st->signum);
567 t->ret = -E_SIGNAL_CAUGHT;
571 static void register_signal_task(void)
573 struct signal_task *st = &signal_task_struct;
574 st->fd = para_signal_init();
575 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
576 para_install_sighandler(SIGINT);
577 para_install_sighandler(SIGTERM);
578 para_install_sighandler(SIGPIPE);
580 st->task.pre_select = signal_pre_select;
581 st->task.post_select = signal_post_select;
582 st->task.private_data = st;
583 sprintf(st->task.status, "signal task");
584 register_task(&st->task);
587 static struct list_head afs_client_list;
590 struct list_head node;
592 struct timeval connect_time;
595 static void command_pre_select(struct sched *s, struct task *t)
597 struct command_task *ct = t->private_data;
598 struct afs_client *client;
600 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
601 list_for_each_entry(client, &afs_client_list, node)
602 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
607 * On errors, negative value is written to fd.
608 * On success: If query produced a result, the result_shmid is written to fd.
609 * Otherwise, zero is written.
611 static int call_callback(int fd, int query_shmid)
613 void *query_shm, *result_shm;
614 struct callback_query *cq;
615 struct callback_result *cr;
616 struct osl_object query, result = {.data = NULL};
617 int result_shmid = -1, ret, ret2;
619 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
623 query.data = (char *)query_shm + sizeof(*cq);
624 query.size = cq->query_size;
625 ret = cq->handler(&query, &result);
626 ret2 = shm_detach(query_shm);
627 if (ret2 < 0 && ret >= 0)
632 if (!result.data || !result.size)
634 ret = shm_new(result.size + sizeof(struct callback_result));
638 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
642 cr->result_size = result.size;
643 memcpy(result_shm + sizeof(*cr), result.data, result.size);
644 ret = shm_detach(result_shm);
650 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
651 if (ret < 0 || ret2 < 0) {
652 if (result_shmid >= 0)
653 if (shm_destroy(result_shmid) < 0)
654 PARA_ERROR_LOG("destroy result failed\n");
661 static void execute_afs_command(int fd, uint32_t expected_cookie)
665 char buf[sizeof(cookie) + sizeof(query_shmid)];
666 int ret = recv_bin_buffer(fd, buf, sizeof(buf));
669 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
672 if (ret != sizeof(buf)) {
673 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
674 ret, (long unsigned) sizeof(buf));
677 cookie = *(uint32_t *)buf;
678 if (cookie != expected_cookie) {
679 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
680 (unsigned)cookie, (unsigned)expected_cookie);
683 query_shmid = *(int *)(buf + sizeof(cookie));
684 if (query_shmid < 0) {
685 PARA_WARNING_LOG("received invalid query shmid %d)\n",
689 /* Ignore return value: Errors might be ok here. */
690 call_callback(fd, query_shmid);
693 #define AFS_CLIENT_TIMEOUT 3
695 static void command_post_select(struct sched *s, struct task *t)
697 struct command_task *ct = t->private_data;
698 struct sockaddr_un unix_addr;
699 struct afs_client *client, *tmp;
701 /* First, check the list of connected clients. */
702 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
703 if (FD_ISSET(client->fd, &s->rfds))
704 execute_afs_command(client->fd, ct->cookie);
705 else { /* prevent bogus connection flodding */
707 tv_diff(now, &client->connect_time, &diff);
708 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
710 PARA_WARNING_LOG("connection timeout\n");
713 list_del(&client->node);
716 /* Next, accept connections on the local socket. */
717 if (!FD_ISSET(ct->fd, &s->rfds))
719 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
721 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
724 client = para_malloc(sizeof(*client));
726 client->connect_time = *now;
727 para_list_add(&client->node, &afs_client_list);
732 static void register_command_task(uint32_t cookie)
734 struct command_task *ct = &command_task_struct;
735 ct->fd = setup_command_socket_or_die();
738 ct->task.pre_select = command_pre_select;
739 ct->task.post_select = command_post_select;
740 ct->task.private_data = ct;
741 sprintf(ct->task.status, "command task");
742 register_task(&ct->task);
745 void register_tasks(uint32_t cookie)
747 register_signal_task();
748 register_command_task(cookie);
751 static char *database_dir;
753 static int make_database_dir(void)
758 if (conf.afs_database_dir_given)
759 database_dir = para_strdup(conf.afs_database_dir_arg);
761 char *home = para_homedir();
762 database_dir = make_message(
763 "%s/.paraslash/afs_database", home);
767 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
768 ret = para_mkdir(database_dir, 0777);
769 if (ret >= 0 || ret == -E_EXIST)
776 static int open_afs_tables(void)
778 int ret = make_database_dir();
782 ret = attribute_init(&afs_tables[TBLNUM_ATTRIBUTES], database_dir);
785 ret = moods_init(&afs_tables[TBLNUM_MOODS], database_dir);
787 goto moods_init_error;
788 ret = playlists_init(&afs_tables[TBLNUM_PLAYLIST], database_dir);
790 goto playlists_init_error;
791 ret = lyrics_init(&afs_tables[TBLNUM_LYRICS], database_dir);
793 goto lyrics_init_error;
794 ret = images_init(&afs_tables[TBLNUM_IMAGES], database_dir);
796 goto images_init_error;
797 ret = score_init(&afs_tables[TBLNUM_SCORES], database_dir);
799 goto score_init_error;
800 ret = aft_init(&afs_tables[TBLNUM_AUDIO_FILES], database_dir);
806 score_shutdown(OSL_MARK_CLEAN);
808 images_shutdown(OSL_MARK_CLEAN);
810 lyrics_shutdown(OSL_MARK_CLEAN);
812 playlists_shutdown(OSL_MARK_CLEAN);
813 playlists_init_error:
814 moods_shutdown(OSL_MARK_CLEAN);
816 attribute_shutdown(OSL_MARK_CLEAN);
820 __noreturn int afs_init(uint32_t cookie, int socket_fd)
822 enum play_mode current_play_mode;
826 INIT_LIST_HEAD(&afs_client_list);
827 ret = open_afs_tables();
830 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
833 server_socket = socket_fd;
834 ret = mark_fd_nonblock(server_socket);
837 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
838 server_socket, (unsigned) cookie);
839 current_play_mode = init_admissible_files();
840 register_tasks(cookie);
841 s.default_timeout.tv_sec = 0;
842 s.default_timeout.tv_usec = 99 * 1000;
845 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
846 close_afs_tables(OSL_MARK_CLEAN);
850 static int create_tables_callback(const struct osl_object *query,
851 __a_unused struct osl_object *result)
853 uint32_t table_mask = *(uint32_t *)query->data;
856 close_afs_tables(OSL_MARK_CLEAN);
857 for (i = 0; i < NUM_AFS_TABLES; i++) {
858 struct table_info *ti = afs_tables + i;
860 if (ti->flags & TBLFLAG_SKIP_CREATE)
862 if (!(table_mask & (1 << i)))
864 ret = osl_create_table(ti->desc);
868 ret = open_afs_tables();
869 return ret < 0? ret: 0;
872 int com_init(int fd, int argc, char * const * const argv)
875 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
876 struct osl_object query = {.data = &table_mask,
877 .size = sizeof(table_mask)};
881 for (i = 1; i < argc; i++) {
882 for (j = 0; j < NUM_AFS_TABLES; j++) {
883 struct table_info *ti = afs_tables + j;
885 if (ti->flags & TBLFLAG_SKIP_CREATE)
887 if (strcmp(argv[i], ti->desc->name))
889 table_mask |= (1 << j);
892 if (j == NUM_AFS_TABLES)
893 return -E_BAD_TABLE_NAME;
896 ret = send_callback_request(create_tables_callback, &query, NULL);
899 return send_va_buffer(fd, "successfully created afs table(s)\n");
902 enum com_check_flags {
908 int com_check(int fd, int argc, char * const * const argv)
912 struct osl_object result;
914 for (i = 1; i < argc; i++) {
915 const char *arg = argv[i];
918 if (!strcmp(arg, "--")) {
922 if (!strcmp(arg, "-a")) {
926 if (!strcmp(arg, "-p")) {
927 flags |= CHECK_PLAYLISTS;
930 if (!strcmp(arg, "-m")) {
931 flags |= CHECK_MOODS;
934 return -E_AFS_SYNTAX;
937 return -E_AFS_SYNTAX;
940 if (flags & CHECK_AFT) {
941 ret = send_callback_request(aft_check_callback, NULL, &result);
945 ret = send_buffer(fd, (char *) result.data);
951 if (flags & CHECK_PLAYLISTS) {
952 ret = send_callback_request(playlist_check_callback, NULL, &result);
956 ret = send_buffer(fd, (char *) result.data);
962 if (flags & CHECK_MOODS) {
963 ret = send_callback_request(mood_check_callback, NULL, &result);
967 ret = send_buffer(fd, (char *) result.data);