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. */
9 #include "server.cmdline.h"
14 #include <dirent.h> /* readdir() */
26 /** The osl tables used by afs. \sa blob.c. */
28 /** Contains audio file information. See aft.c. */
30 /** The table for the paraslash attributes. See attribute.c. */
33 * Paraslash's scoring system is based on Gaussian normal
34 * distributions, and the relevant data is stored in the rbtrees of an
35 * osl table containing only volatile columns. See score.c for
40 * A standard blob table containing the mood definitions. For details
44 /** A blob table containing lyrics on a per-song basis. */
46 /** Another blob table for images (for example album cover art). */
48 /** Yet another blob table for storing standard playlists. */
50 /** How many tables are in use? */
54 static struct table_info afs_tables[NUM_AFS_TABLES];
57 /** The file descriptor for the local socket. */
60 * Value sent by the command handlers to identify themselves as
61 * children of the running para_server.
64 /** The associated task structure. */
69 * A random number used to "authenticate" the connection.
71 * para_server picks this number by random before forking the afs process. The
72 * command handlers write this number together with the id of the shared memory
73 * area containing the query. This way, a malicious local user has to know this
74 * number to be able to cause the afs process to crash by sending fake queries.
76 extern uint32_t afs_socket_cookie;
79 * Struct to let command handlers execute a callback in afs context.
81 * Commands that need to change the state of afs can't change the relevant data
82 * structures directly because commands are executed in a child process, i.e.
83 * they get their own virtual address space.
85 * This structure is used by \p send_callback_request() (executed from handler
86 * context) in order to let the afs process call the specified function. An
87 * instance of that structure is written to a shared memory area together with
88 * the arguments to the callback function. The identifier of the shared memory
89 * area is written to the command socket.
91 * The afs process accepts connections on the command socket and reads the
92 * shared memory id, attaches the corresponing area, calls the given handler to
93 * perform the desired action and to optionally compute a result.
95 * The result and a \p callback_result structure is then written to another
96 * shared memory area. The identifier for that area is written to the handler's
97 * command socket, so that the handler process can read the id, attach the
98 * shared memory area and use the result.
100 * \sa struct callback_result.
102 struct callback_query {
103 /** The function to be called. */
104 callback_function *handler;
105 /** The number of bytes of the query */
110 * Structure embedded in the result of a callback.
112 * If the callback produced a result, an instance of that structure is embeeded
113 * into the shared memory area holding the result, mainly to let the command
114 * handler know the size of the result.
116 * \sa struct callback_query.
118 struct callback_result {
119 /** The number of bytes of the result. */
124 * Ask the parent process to call a given function.
126 * \param f The function to be called.
127 * \param query Pointer to arbitrary data for the callback.
128 * \param result Callback result will be stored here.
130 * This function creates a shared memory area, copies the buffer pointed to by
131 * \a buf to that area and notifies the afs process that \a f should be
134 * \return Negative, on errors, the return value of the callback function
137 * \sa send_option_arg_callback_request(), send_standard_callback_request().
139 int send_callback_request(callback_function *f, struct osl_object *query,
140 struct osl_object *result)
142 struct callback_query *cq;
143 struct callback_result *cr;
144 int ret, fd = -1, query_shmid, result_shmid;
145 void *query_shm, *result_shm;
146 char buf[sizeof(afs_socket_cookie) + sizeof(int)];
147 // char *tmpsocket_name;
148 struct sockaddr_un unix_addr;
150 assert(query->data && query->size);
151 ret = shm_new(query->size + sizeof(*cq));
155 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
160 cq->query_size = query->size;
162 memcpy(query_shm + sizeof(*cq), query->data, query->size);
163 ret = shm_detach(query_shm);
167 *(uint32_t *) buf = afs_socket_cookie;
168 *(int *) (buf + sizeof(afs_socket_cookie)) = query_shmid;
170 ret = get_stream_socket(PF_UNIX);
174 ret = init_unix_addr(&unix_addr, conf.afs_socket_arg);
177 ret = PARA_CONNECT(fd, &unix_addr);
180 ret = send_bin_buffer(fd, buf, sizeof(buf));
183 ret = recv_bin_buffer(fd, buf, sizeof(buf));
186 if (ret != sizeof(int)) {
194 ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
198 result->size = cr->result_size;
199 result->data = para_malloc(result->size);
200 memcpy(result->data, result_shm + sizeof(*cr), result->size);
201 ret = shm_detach(result_shm);
203 PARA_ERROR_LOG("can not detach result\n");
205 PARA_ERROR_LOG("attach result failed: %d\n", ret);
206 if (shm_destroy(result_shmid) < 0)
207 PARA_ERROR_LOG("destroy result failed\n");
210 if (shm_destroy(query_shmid) < 0)
211 PARA_ERROR_LOG("%s\n", "shm destroy error");
214 // PARA_DEBUG_LOG("callback_ret: %d\n", ret);
219 * Send a callback request passing an options structure and an argument vector.
221 * \param options pointer to an arbitrary data structure.
222 * \param argc Argument count.
223 * \param argv Standard argument vector.
224 * \param f The callback function.
225 * \param result The result of the query is stored here.
227 * Some commands have a couple of options that are parsed in child context for
228 * syntactic correctness and are stored in a special options structure for that
229 * command. This function allows to pass such a structure together with a list
230 * of further arguments (often a list of audio files) to the parent process.
232 * \sa send_standard_callback_request(), send_callback_request().
234 int send_option_arg_callback_request(struct osl_object *options,
235 int argc, char * const * const argv, callback_function *f,
236 struct osl_object *result)
240 struct osl_object query = {.size = options? options->size : 0};
242 for (i = 0; i < argc; i++)
243 query.size += strlen(argv[i]) + 1;
244 query.data = para_malloc(query.size);
247 memcpy(query.data, options->data, options->size);
250 for (i = 0; i < argc; i++) {
251 strcpy(p, argv[i]); /* OK */
252 p += strlen(argv[i]) + 1;
254 ret = send_callback_request(f, &query, result);
260 * Send a callback request with an argument vector only.
262 * \param argc The same meaning as in send_option_arg_callback_request().
263 * \param argv The same meaning as in send_option_arg_callback_request().
264 * \param f The same meaning as in send_option_arg_callback_request().
265 * \param result The same meaning as in send_option_arg_callback_request().
267 * This is similar to send_option_arg_callback_request(), but no options buffer
268 * is passed to the parent process.
270 * \return The return value of the underlying call to
271 * send_option_arg_callback_request().
273 int send_standard_callback_request(int argc, char * const * const argv,
274 callback_function *f, struct osl_object *result)
276 return send_option_arg_callback_request(NULL, argc, argv, f, result);
280 * Compare two osl objects of string type.
282 * \param obj1 Pointer to the first object.
283 * \param obj2 Pointer to the second object.
285 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
286 * are taken into account.
288 * \return It returns an integer less than, equal to, or greater than zero if
289 * \a obj1 is found, respectively, to be less than, to match, or be greater than
292 * \sa strcmp(3), strncmp(3), osl_compare_func.
294 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
296 const char *str1 = (const char *)obj1->data;
297 const char *str2 = (const char *)obj2->data;
298 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
302 * A wrapper for strtol(3).
304 * \param str The string to be converted to a long integer.
305 * \param result The converted value is stored here.
307 * \return Positive on success, -E_ATOL on errors.
309 * \sa strtol(3), atoi(3).
311 int para_atol(const char *str, long *result)
317 errno = 0; /* To distinguish success/failure after call */
318 val = strtol(str, &endptr, base);
320 if (errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
321 goto out; /* overflow */
322 if (errno != 0 && val == 0)
323 goto out; /* other error */
325 goto out; /* No digits were found */
327 goto out; /* Further characters after number */
336 * write input from fd to dynamically allocated buffer,
337 * but maximal max_size byte.
339 static int fd2buf(int fd, unsigned max_size, struct osl_object *obj)
341 const size_t chunk_size = 1024;
342 size_t size = 2048, received = 0;
344 char *buf = para_malloc(size);
347 ret = recv_bin_buffer(fd, buf + received, chunk_size);
351 if (received + chunk_size >= size) {
353 ret = -E_INPUT_TOO_LARGE;
356 buf = para_realloc(buf, size);
360 obj->size = received;
367 * Read from stdin, and send the result to the parent process.
369 * \param arg_obj Pointer to the arguments to \a f.
370 * \param f The callback function.
371 * \param max_len Don't read more than that many bytes from stdin.
372 * \param result The result of the query is stored here.
374 * This function is used by commands that wish to let para_server store
375 * arbitrary data specified by the user (for instance the add_blob family of
376 * commands). First, at most \a max_len bytes are read from stdin, the result
377 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
378 * is made available to the parent process via shared memory.
380 * \return Negative on errors, the return value of the underlying call to
381 * send_callback_request() otherwise.
383 int stdin_command(int fd, struct osl_object *arg_obj, callback_function *f,
384 unsigned max_len, struct osl_object *result)
386 struct osl_object query, stdin_obj;
389 ret = send_buffer(fd, AWAITING_DATA_MSG);
392 ret = fd2buf(fd, max_len, &stdin_obj);
395 query.size = arg_obj->size + stdin_obj.size;
396 query.data = para_malloc(query.size);
397 memcpy(query.data, arg_obj->data, arg_obj->size);
398 memcpy((char *)query.data + arg_obj->size, stdin_obj.data, stdin_obj.size);
399 free(stdin_obj.data);
400 ret = send_callback_request(f, &query, result);
406 * Open the audio file with highest score.
408 * \param afd Audio file data is returned here.
410 * This stores all information for streaming the "best" audio file
411 * in the \a afd structure.
413 * \return Positive on success, negative on errors.
415 * \sa close_audio_file(), open_and_update_audio_file().
417 int open_next_audio_file(struct audio_file_data *afd)
419 struct osl_row *aft_row;
422 ret = score_get_best(&aft_row, &afd->score);
425 ret = open_and_update_audio_file(aft_row, afd);
432 * Free all resources which were allocated by open_next_audio_file().
434 * \param afd The structure previously filled in by open_next_audio_file().
436 * \return The return value of the underlying call to para_munmap().
438 * \sa open_next_audio_file().
440 int close_audio_file(struct audio_file_data *afd)
442 free(afd->afhi.chunk_table);
443 return para_munmap(afd->map.data, afd->map.size);
447 static void play_loop(enum play_mode current_play_mode)
450 struct audio_file_data afd;
452 afd.current_play_mode = current_play_mode;
453 for (i = 0; i < 0; i++) {
454 ret = open_next_audio_file(&afd);
456 PARA_ERROR_LOG("failed to open next audio file: %d\n", ret);
459 PARA_NOTICE_LOG("next audio file: %s, score: %li\n", afd.path, afd.score);
461 close_audio_file(&afd);
467 static enum play_mode init_admissible_files(void)
470 char *given_mood, *given_playlist;
472 given_mood = "mood_that_was_given_at_the_command_line";
473 given_playlist = "given_playlist";
476 ret = mood_open(given_mood);
479 PARA_WARNING_LOG("ignoring playlist %s\n",
481 return PLAY_MODE_MOOD;
484 if (given_playlist) {
485 ret = playlist_open(given_playlist);
487 return PLAY_MODE_PLAYLIST;
489 ret = mood_open(NULL); /* open first available mood */
491 return PLAY_MODE_MOOD;
492 mood_open(""); /* open dummy mood, always successful */
493 return PLAY_MODE_MOOD;
496 static int setup_command_socket_or_die(void)
499 char *socket_name = conf.afs_socket_arg;
500 struct sockaddr_un unix_addr;
503 ret = create_local_socket(socket_name, &unix_addr,
504 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
506 PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
509 if (listen(ret , 5) < 0) {
510 PARA_EMERG_LOG("%s", "can not listen on socket\n");
513 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
518 static int server_socket;
519 static struct command_task command_task_struct;
520 static struct signal_task signal_task_struct;
522 static void unregister_tasks(void)
524 unregister_task(&command_task_struct.task);
525 unregister_task(&signal_task_struct.task);
528 static void close_afs_tables(enum osl_close_flags flags)
530 PARA_NOTICE_LOG("closing afs_tables\n");
531 score_shutdown(flags);
532 attribute_shutdown(flags);
535 moods_shutdown(flags);
536 playlists_shutdown(flags);
537 lyrics_shutdown(flags);
538 images_shutdown(flags);
542 static void signal_pre_select(struct sched *s, struct task *t)
544 struct signal_task *st = t->private_data;
546 para_fd_set(st->fd, &s->rfds, &s->max_fileno);
549 static void signal_post_select(struct sched *s, struct task *t)
551 struct signal_task *st = t->private_data;
553 if (!FD_ISSET(st->fd, &s->rfds))
555 st->signum = para_next_signal();
556 PARA_NOTICE_LOG("caught signal %d\n", st->signum);
558 if (st->signum == SIGUSR1)
559 return; /* ignore SIGUSR1 */
560 t->ret = -E_SIGNAL_CAUGHT;
564 static void register_signal_task(void)
566 struct signal_task *st = &signal_task_struct;
567 st->fd = para_signal_init();
568 PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
569 para_install_sighandler(SIGINT);
570 para_install_sighandler(SIGTERM);
571 para_install_sighandler(SIGPIPE);
573 st->task.pre_select = signal_pre_select;
574 st->task.post_select = signal_post_select;
575 st->task.private_data = st;
576 sprintf(st->task.status, "signal task");
577 register_task(&st->task);
580 static void command_pre_select(struct sched *s, struct task *t)
582 struct command_task *ct = t->private_data;
584 para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
588 * On errors, negative value is written to fd.
589 * On success: If query produced a result, the result_shmid is written to fd.
590 * Otherwise, zero is written.
592 static int call_callback(int fd, int query_shmid)
594 void *query_shm, *result_shm;
595 struct callback_query *cq;
596 struct callback_result *cr;
597 struct osl_object query, result = {.data = NULL};
598 int result_shmid = -1, ret, ret2;
600 ret = shm_attach(query_shmid, ATTACH_RW, &query_shm);
604 query.data = (char *)query_shm + sizeof(*cq);
605 query.size = cq->query_size;
606 ret = cq->handler(&query, &result);
607 ret2 = shm_detach(query_shm);
608 if (ret2 < 0 && ret >= 0)
613 if (!result.data || !result.size)
615 ret = shm_new(result.size + sizeof(struct callback_result));
619 ret = shm_attach(result_shmid, ATTACH_RW, &result_shm);
623 cr->result_size = result.size;
624 memcpy(result_shm + sizeof(*cr), result.data, result.size);
625 ret = shm_detach(result_shm);
631 ret2 = send_bin_buffer(fd, (char *)&ret, sizeof(int));
632 if (ret < 0 || ret2 < 0) {
633 if (result_shmid >= 0)
634 if (shm_destroy(result_shmid) < 0)
635 PARA_ERROR_LOG("destroy result failed\n");
642 static void command_post_select(struct sched *s, struct task *t)
644 struct command_task *ct = t->private_data;
645 struct sockaddr_un unix_addr;
646 char buf[sizeof(uint32_t) + sizeof(int)];
651 if (!FD_ISSET(ct->fd, &s->rfds))
653 t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
657 * The following errors may be caused by a malicious local user. So do
658 * not return an error in this case as this would terminate para_afs
662 /* FIXME: This is easily dosable (peer doesn't send data) */
663 t->ret = recv_bin_buffer(fd, buf, sizeof(buf));
665 PARA_NOTICE_LOG("%s (%d)\n", PARA_STRERROR(-t->ret), t->ret);
668 if (t->ret != sizeof(buf)) {
669 PARA_NOTICE_LOG("short read (%d bytes, expected %lu)\n",
670 t->ret, (long unsigned) sizeof(buf));
673 cookie = *(uint32_t *)buf;
674 if (cookie != ct->cookie) {
675 PARA_NOTICE_LOG("received invalid cookie(got %u, expected %u)\n",
676 (unsigned)cookie, (unsigned)ct->cookie);
679 query_shmid = *(int *)(buf + sizeof(cookie));
680 if (query_shmid < 0) {
681 PARA_WARNING_LOG("received invalid query shmid %d)\n",
685 /* Ignore return value: Errors might be ok here. */
686 call_callback(fd, query_shmid);
692 static void register_command_task(uint32_t cookie)
694 struct command_task *ct = &command_task_struct;
695 ct->fd = setup_command_socket_or_die();
698 ct->task.pre_select = command_pre_select;
699 ct->task.post_select = command_post_select;
700 ct->task.private_data = ct;
701 sprintf(ct->task.status, "command task");
702 register_task(&ct->task);
705 void register_tasks(uint32_t cookie)
707 register_signal_task();
708 register_command_task(cookie);
711 static char *database_dir;
713 static int make_database_dir(void)
718 if (conf.afs_database_dir_given)
719 database_dir = para_strdup(conf.afs_database_dir_arg);
721 char *home = para_homedir();
722 database_dir = make_message(
723 "%s/.paraslash/afs_database", home);
727 PARA_INFO_LOG("afs_database dir %s\n", database_dir);
728 ret = para_mkdir(database_dir, 0777);
729 if (ret >= 0 || ret == -E_EXIST)
736 static int open_afs_tables(void)
738 int ret = make_database_dir();
742 ret = attribute_init(&afs_tables[TBLNUM_ATTRIBUTES], database_dir);
745 ret = moods_init(&afs_tables[TBLNUM_MOODS], database_dir);
747 goto moods_init_error;
748 ret = playlists_init(&afs_tables[TBLNUM_PLAYLIST], database_dir);
750 goto playlists_init_error;
751 ret = lyrics_init(&afs_tables[TBLNUM_LYRICS], database_dir);
753 goto lyrics_init_error;
754 ret = images_init(&afs_tables[TBLNUM_IMAGES], database_dir);
756 goto images_init_error;
757 ret = score_init(&afs_tables[TBLNUM_SCORES], database_dir);
759 goto score_init_error;
760 ret = aft_init(&afs_tables[TBLNUM_AUDIO_FILES], database_dir);
766 score_shutdown(OSL_MARK_CLEAN);
768 images_shutdown(OSL_MARK_CLEAN);
770 lyrics_shutdown(OSL_MARK_CLEAN);
772 playlists_shutdown(OSL_MARK_CLEAN);
773 playlists_init_error:
774 moods_shutdown(OSL_MARK_CLEAN);
776 attribute_shutdown(OSL_MARK_CLEAN);
780 __noreturn int afs_init(uint32_t cookie, int socket_fd)
782 enum play_mode current_play_mode;
784 int ret = open_afs_tables();
787 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
790 server_socket = socket_fd;
791 ret = mark_fd_nonblock(server_socket);
794 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
795 server_socket, (unsigned) cookie);
796 current_play_mode = init_admissible_files();
797 register_tasks(cookie);
798 s.default_timeout.tv_sec = 0;
799 s.default_timeout.tv_usec = 99 * 1000;
802 PARA_EMERG_LOG("%s\n", PARA_STRERROR(-ret));
803 close_afs_tables(OSL_MARK_CLEAN);
807 static int create_tables_callback(const struct osl_object *query,
808 __a_unused struct osl_object *result)
810 uint32_t table_mask = *(uint32_t *)query->data;
813 close_afs_tables(OSL_MARK_CLEAN);
814 for (i = 0; i < NUM_AFS_TABLES; i++) {
815 struct table_info *ti = afs_tables + i;
817 if (ti->flags & TBLFLAG_SKIP_CREATE)
819 if (!(table_mask & (1 << i)))
821 ret = osl_create_table(ti->desc);
825 ret = open_afs_tables();
826 return ret < 0? ret: 0;
829 int com_init(int fd, int argc, char * const * const argv)
832 uint32_t table_mask = (1 << (NUM_AFS_TABLES + 1)) - 1;
833 struct osl_object query = {.data = &table_mask,
834 .size = sizeof(table_mask)};
838 for (i = 1; i < argc; i++) {
839 for (j = 0; j < NUM_AFS_TABLES; j++) {
840 struct table_info *ti = afs_tables + j;
842 if (ti->flags & TBLFLAG_SKIP_CREATE)
844 if (strcmp(argv[i], ti->desc->name))
846 table_mask |= (1 << j);
849 if (j == NUM_AFS_TABLES)
850 return -E_BAD_TABLE_NAME;
853 ret = send_callback_request(create_tables_callback, &query, NULL);
856 return send_va_buffer(fd, "successfully created afs table(s)\n");