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);
453 static enum play_mode init_admissible_files(void)
457 if (conf.mood_given) {
458 ret = change_current_mood(conf.mood_arg);
460 if (conf.playlist_given)
461 PARA_WARNING_LOG("ignoring playlist %s\n",
463 return PLAY_MODE_MOOD;
466 if (conf.playlist_given) {
467 ret = playlist_open(conf.playlist_arg);
469 return PLAY_MODE_PLAYLIST;
471 ret = change_current_mood(NULL); /* open first available mood */
473 return PLAY_MODE_MOOD;
474 change_current_mood(""); /* open dummy mood, always successful */
475 return PLAY_MODE_MOOD;
478 static int setup_command_socket_or_die(void)
481 char *socket_name = conf.afs_socket_arg;
482 struct sockaddr_un unix_addr;
485 ret = create_local_socket(socket_name, &unix_addr,
486 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
488 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
491 if (listen(ret , 5) < 0) {
492 PARA_EMERG_LOG("%s", "can not listen on socket\n");
495 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
500 static void close_afs_tables(enum osl_close_flags flags)
502 PARA_NOTICE_LOG("closing afs_tables\n");
503 score_shutdown(flags);
504 attribute_shutdown(flags);
505 close_current_mood();
507 moods_shutdown(flags);
508 playlists_shutdown(flags);
509 lyrics_shutdown(flags);
510 images_shutdown(flags);
514 static char *database_dir;
516 static int make_database_dir(void)
521 if (conf.afs_database_dir_given)
522 database_dir = para_strdup(conf.afs_database_dir_arg);
524 char *home = para_homedir();
525 database_dir = make_message(
526 "%s/.paraslash/afs_database", home);
530 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
531 ret = para_mkdir(database_dir, 0777);
532 if (ret >= 0 || ret == -E_EXIST)
540 static int open_afs_tables(void)
542 int ret = make_database_dir();
546 ret = attribute_init(&afs_tables[TBLNUM_ATTRIBUTES], database_dir);
549 ret = moods_init(&afs_tables[TBLNUM_MOODS], database_dir);
551 goto moods_init_error;
552 ret = playlists_init(&afs_tables[TBLNUM_PLAYLIST], database_dir);
554 goto playlists_init_error;
555 ret = lyrics_init(&afs_tables[TBLNUM_LYRICS], database_dir);
557 goto lyrics_init_error;
558 ret = images_init(&afs_tables[TBLNUM_IMAGES], database_dir);
560 goto images_init_error;
561 ret = score_init(&afs_tables[TBLNUM_SCORES], database_dir);
563 goto score_init_error;
564 ret = aft_init(&afs_tables[TBLNUM_AUDIO_FILES], database_dir);
570 score_shutdown(OSL_MARK_CLEAN);
572 images_shutdown(OSL_MARK_CLEAN);
574 lyrics_shutdown(OSL_MARK_CLEAN);
576 playlists_shutdown(OSL_MARK_CLEAN);
577 playlists_init_error:
578 moods_shutdown(OSL_MARK_CLEAN);
580 attribute_shutdown(OSL_MARK_CLEAN);
584 static int server_socket;
585 static struct command_task command_task_struct;
586 static struct signal_task signal_task_struct;
588 static void unregister_tasks(void)
590 unregister_task(&command_task_struct.task);
591 unregister_task(&signal_task_struct.task);
594 static void signal_pre_select(struct sched *s, struct task *t)
596 struct signal_task *st = t->private_data;
598 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
601 static void signal_post_select(struct sched *s, struct task *t)
603 struct signal_task *st = t->private_data;
605 if (!FD_ISSET(st->fd, &s->rfds))
607 st->signum = para_next_signal();
609 if (st->signum == SIGUSR1)
610 return; /* ignore SIGUSR1 */
611 if (st->signum == SIGHUP) {
612 close_afs_tables(OSL_MARK_CLEAN);
613 t->ret = open_afs_tables();
616 PARA_NOTICE_LOG("caught signal %d\n", st->signum);
617 t->ret = -E_SIGNAL_CAUGHT;
621 static void register_signal_task(void)
623 struct signal_task *st = &signal_task_struct;
624 st->fd = para_signal_init();
625 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
626 para_install_sighandler(SIGINT);
627 para_install_sighandler(SIGTERM);
628 para_install_sighandler(SIGPIPE);
629 para_install_sighandler(SIGHUP);
631 st->task.pre_select = signal_pre_select;
632 st->task.post_select = signal_post_select;
633 st->task.private_data = st;
634 sprintf(st->task.status, "signal task");
635 register_task(&st->task);
638 static struct list_head afs_client_list;
641 struct list_head node;
643 struct timeval connect_time;
646 static void command_pre_select(struct sched *s, struct task *t)
648 struct command_task *ct = t->private_data;
649 struct afs_client *client;
651 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
652 list_for_each_entry(client, &afs_client_list, node)
653 para_fd_set(client->fd, &s->rfds, &s->max_fileno);
658 * On errors, negative value is written to fd.
659 * On success: If query produced a result, the result_shmid is written to fd.
660 * Otherwise, zero is written.
662 static int call_callback(int fd, int query_shmid)
664 void *query_shm, *result_shm;
665 struct callback_query *cq;
666 struct callback_result *cr;
667 struct osl_object query, result = {.data = NULL};
668 int result_shmid = -1, ret, ret2;
670 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
674 query.data = (char *)query_shm + sizeof(*cq);
675 query.size = cq->query_size;
676 ret = cq->handler(&query, &result);
677 ret2 = shm_detach(query_shm);
678 if (ret2 < 0 && ret >= 0)
683 if (!result.data || !result.size)
685 ret = shm_new(result.size + sizeof(struct callback_result));
689 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
693 cr->result_size = result.size;
694 memcpy(result_shm + sizeof(*cr), result.data, result.size);
695 ret = shm_detach(result_shm);
701 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
702 if (ret < 0 || ret2 < 0) {
703 if (result_shmid >= 0)
704 if (shm_destroy(result_shmid) < 0)
705 PARA_ERROR_LOG("destroy result failed\n");
712 static void execute_afs_command(int fd, uint32_t expected_cookie)
716 char buf[sizeof(cookie) + sizeof(query_shmid)];
717 int ret = recv_bin_buffer(fd, buf, sizeof(buf));
720 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-ret));
723 if (ret != sizeof(buf)) {
724 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
725 ret, (long unsigned) sizeof(buf));
728 cookie = *(uint32_t *)buf;
729 if (cookie != expected_cookie) {
730 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
731 (unsigned)cookie, (unsigned)expected_cookie);
734 query_shmid = *(int *)(buf + sizeof(cookie));
735 if (query_shmid < 0) {
736 PARA_WARNING_LOG("received invalid query shmid %d)\n",
740 /* Ignore return value: Errors might be ok here. */
741 call_callback(fd, query_shmid);
744 #define AFS_CLIENT_TIMEOUT 3
746 static void command_post_select(struct sched *s, struct task *t)
748 struct command_task *ct = t->private_data;
749 struct sockaddr_un unix_addr;
750 struct afs_client *client, *tmp;
752 /* First, check the list of connected clients. */
753 list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
754 if (FD_ISSET(client->fd, &s->rfds))
755 execute_afs_command(client->fd, ct->cookie);
756 else { /* prevent bogus connection flodding */
758 tv_diff(now, &client->connect_time, &diff);
759 if (diff.tv_sec < AFS_CLIENT_TIMEOUT)
761 PARA_WARNING_LOG("connection timeout\n");
764 list_del(&client->node);
767 /* Next, accept connections on the local socket. */
768 if (!FD_ISSET(ct->fd, &s->rfds))
770 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
772 PARA_NOTICE_LOG("%s\n", PARA_STRERROR(-t->ret));
775 client = para_malloc(sizeof(*client));
777 client->connect_time = *now;
778 para_list_add(&client->node, &afs_client_list);
783 static void register_command_task(uint32_t cookie)
785 struct command_task *ct = &command_task_struct;
786 ct->fd = setup_command_socket_or_die();
789 ct->task.pre_select = command_pre_select;
790 ct->task.post_select = command_post_select;
791 ct->task.private_data = ct;
792 sprintf(ct->task.status, "command task");
793 register_task(&ct->task);
796 void register_tasks(uint32_t cookie)
798 register_signal_task();
799 register_command_task(cookie);
802 __noreturn int afs_init(uint32_t cookie, int socket_fd)
804 enum play_mode current_play_mode;
808 INIT_LIST_HEAD(&afs_client_list);
809 ret = open_afs_tables();
812 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
815 server_socket = socket_fd;
816 ret = mark_fd_nonblock(server_socket);
819 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
820 server_socket, (unsigned) cookie);
821 current_play_mode = init_admissible_files();
822 register_tasks(cookie);
823 s.default_timeout.tv_sec = 0;
824 s.default_timeout.tv_usec = 99 * 1000;
827 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
828 close_afs_tables(OSL_MARK_CLEAN);
832 static int create_tables_callback(const struct osl_object *query,
833 __a_unused struct osl_object *result)
835 uint32_t table_mask = *(uint32_t *)query->data;
838 close_afs_tables(OSL_MARK_CLEAN);
839 for (i = 0; i < NUM_AFS_TABLES; i++) {
840 struct table_info *ti = afs_tables + i;
842 if (ti->flags & TBLFLAG_SKIP_CREATE)
844 if (!(table_mask & (1 << i)))
846 ret = osl_create_table(ti->desc);
850 ret = open_afs_tables();
851 return ret < 0? ret: 0;
854 int com_init(int fd, int argc, char * const * const argv)
857 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
858 struct osl_object query = {.data = &table_mask,
859 .size = sizeof(table_mask)};
863 for (i = 1; i < argc; i++) {
864 for (j = 0; j < NUM_AFS_TABLES; j++) {
865 struct table_info *ti = afs_tables + j;
867 if (ti->flags & TBLFLAG_SKIP_CREATE)
869 if (strcmp(argv[i], ti->desc->name))
871 table_mask |= (1 << j);
874 if (j == NUM_AFS_TABLES)
875 return -E_BAD_TABLE_NAME;
878 ret = send_callback_request(create_tables_callback, &query, NULL);
881 return send_va_buffer(fd, "successfully created afs table(s)\n");
884 enum com_check_flags {
890 int com_check(int fd, int argc, char * const * const argv)
894 struct osl_object result;
896 for (i = 1; i < argc; i++) {
897 const char *arg = argv[i];
900 if (!strcmp(arg, "--")) {
904 if (!strcmp(arg, "-a")) {
908 if (!strcmp(arg, "-p")) {
909 flags |= CHECK_PLAYLISTS;
912 if (!strcmp(arg, "-m")) {
913 flags |= CHECK_MOODS;
916 return -E_AFS_SYNTAX;
919 return -E_AFS_SYNTAX;
922 if (flags & CHECK_AFT) {
923 ret = send_callback_request(aft_check_callback, NULL, &result);
927 ret = send_buffer(fd, (char *) result.data);
933 if (flags & CHECK_PLAYLISTS) {
934 ret = send_callback_request(playlist_check_callback, NULL, &result);
938 ret = send_buffer(fd, (char *) result.data);
944 if (flags & CHECK_MOODS) {
945 ret = send_callback_request(mood_check_callback, NULL, &result);
949 ret = send_buffer(fd, (char *) result.data);