4 #include <dirent.h> /* readdir() */
14 /** \file afs.c Paraslash's audio file selector. */
16 static uint32_t socket_cookie;
19 * Compare two osl objects of string type.
21 * \param obj1 Pointer to the first object.
22 * \param obj2 Pointer to the second object.
24 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
25 * are taken into account.
27 * \return It returns an integer less than, equal to, or greater than zero if
28 * \a obj1 is found, respectively, to be less than, to match, or be greater than
31 * \sa strcmp(3), strncmp(3), osl_compare_func.
33 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
35 const char *str1 = (const char *)obj1->data;
36 const char *str2 = (const char *)obj2->data;
37 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
40 /** The osl tables used by afs. \sa blob.c */
42 /** Contains audio file information. See aft.c. */
44 /** The table for the paraslash attributes. See attribute.c. */
47 * Paraslash's scoring system is based on Gaussian normal
48 * distributions, and the relevant data is stored in the rbtrees of an
49 * osl table containing only volatile columns. See score.c for
54 * A standard blob table containing the mood definitions. For details
58 /** A blob table containing lyrics on a per-song basis. */
60 /** Another blob table for images (for example album cover art). */
62 /** Yet another blob table for storing standard playlists. */
64 /** How many tables are in use? */
68 static struct table_info afs_tables[NUM_AFS_TABLES];
72 * A wrapper for strtol(3).
74 * \param str The string to be converted to a long integer.
75 * \param result The converted value is stored here.
77 * \return Positive on success, -E_ATOL on errors.
79 * \sa strtol(3), atoi(3).
81 int para_atol(const char *str, long *result)
87 errno = 0; /* To distinguish success/failure after call */
88 val = strtol(str, &endptr, base);
90 if (errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
91 goto out; /* overflow */
92 if (errno != 0 && val == 0)
93 goto out; /* other error */
95 goto out; /* No digits were found */
97 goto out; /* Further characters after number */
105 * Struct to let para_server call a function specified from child context.
107 * Commands that need to change the state of para_server can't
108 * change the relevant data structures directly because commands
109 * are executed in a child process, i.e. they get their own
110 * virtual address space. This structure must be used to let
111 * para_server (i.e. the parent process) call a function specified
112 * by the child (the command handler).
114 * \sa fork(2), ipc.c.
116 struct callback_data {
117 /** The function to be called. */
118 callback_function *handler;
119 /** The sma for the parameters of the callback function. */
121 /** The size of the query sma. */
123 /** If the callback produced a result, it is stored in this sma. */
125 /** The size of the result sma. */
127 /** The return value of the callback function. */
129 /** The return value of the callback() procedure. */
133 static struct callback_data *shm_callback_data;
134 static int callback_mutex;
135 static int child_mutex;
136 static int result_mutex;
139 * Ask the parent process to call a given function.
141 * \param f The function to be called.
142 * \param query Pointer to arbitrary data for the callback.
143 * \param result Callback result will be stored here.
145 * This function creates a shared memory area, copies the buffer pointed to by
146 * \a buf to that area and notifies the parent process that \a f should be
147 * called ASAP. It provides proper locking via semaphores to protect against
148 * concurent access to the shared memory area and against concurrent access by
149 * another child process that asks to call the same function.
151 * \return Negative, if the shared memory area could not be set up. The return
152 * value of the callback function otherwise.
154 * \sa shm_new(), shm_attach(), shm_detach(), mutex_lock(), mutex_unlock(),
155 * shm_destroy(), struct callback_data, send_option_arg_callback_request(),
156 * send_standard_callback_request().
158 int send_callback_request(callback_function *f, struct osl_object *query,
159 struct osl_object *result)
161 struct callback_data cbd = {.handler = f};
165 assert(query->data && query->size);
166 ret = shm_new(query->size);
169 cbd.query_shmid = ret;
170 cbd.query_size = query->size;
171 ret = shm_attach(cbd.query_shmid, ATTACH_RW, &query_sma);
174 memcpy(query_sma, query->data, query->size);
175 ret = shm_detach(query_sma);
178 /* prevent other children from interacting */
179 mutex_lock(child_mutex);
180 /* prevent parent from messing with shm_callback_data. */
181 mutex_lock(callback_mutex);
182 /* all three mutexes are locked, set parameters for callback */
183 *shm_callback_data = cbd;
185 mutex_unlock(callback_mutex);
186 kill(getppid(), SIGUSR1); /* wake up parent */
188 * At this time only the parent can run. It will execute our callback
189 * and unlock the result_mutex when ready to indicate that the child
190 * may use the result. So let's sleep on this mutex.
192 mutex_lock(result_mutex);
193 /* No need to aquire the callback mutex again */
194 ret = shm_callback_data->sma_ret;
195 if (ret < 0) /* sma problem, callback might not have been executed */
196 goto unlock_child_mutex;
197 if (shm_callback_data->result_shmid >= 0) { /* parent provided a result */
199 ret = shm_attach(shm_callback_data->result_shmid, ATTACH_RO,
202 if (result) { /* copy result */
203 result->size = shm_callback_data->result_size;
204 result->data = para_malloc(result->size);
205 memcpy(result->data, sma, result->size);
206 ret = shm_detach(sma);
208 PARA_ERROR_LOG("can not detach result\n");
210 PARA_WARNING_LOG("no result pointer\n");
212 PARA_ERROR_LOG("attach result failed: %d\n", ret);
213 if (shm_destroy(shm_callback_data->result_shmid) < 0)
214 PARA_ERROR_LOG("destroy result failed\n");
215 } else { /* no result from callback */
217 PARA_WARNING_LOG("callback has no result\n");
222 ret = shm_callback_data->callback_ret;
224 /* give other children a chance */
225 mutex_unlock(child_mutex);
227 if (shm_destroy(cbd.query_shmid) < 0)
228 PARA_ERROR_LOG("%s\n", "shm destroy error");
229 PARA_DEBUG_LOG("callback_ret: %d\n", ret);
234 * Send a callback request passing an options structure and an argument vector.
236 * \param options pointer to an arbitrary data structure.
237 * \param argc Argument count.
238 * \param argv Standard argument vector.
239 * \param f The callback function.
240 * \param result The result of the query is stored here.
242 * Some commands have a couple of options that are parsed in child context for
243 * syntactic correctness and are stored in a special options structure for that
244 * command. This function allows to pass such a structure together with a list
245 * of further arguments (often a list of audio files) to the parent process.
247 * \sa send_standard_callback_request(), send_callback_request().
249 int send_option_arg_callback_request(struct osl_object *options,
250 int argc, const char **argv, callback_function *f,
251 struct osl_object *result)
255 struct osl_object query = {.size = options? options->size : 0};
257 for (i = 0; i < argc; i++)
258 query.size += strlen(argv[i]) + 1;
259 query.data = para_malloc(query.size);
262 memcpy(query.data, options->data, options->size);
265 for (i = 0; i < argc; i++) {
266 strcpy(p, argv[i]); /* OK */
267 p += strlen(argv[i]) + 1;
269 ret = send_callback_request(f, &query, result);
275 * Send a callback request with an argument vector only.
277 * \param argc The same meaning as in send_option_arg_callback_request().
278 * \param argv The same meaning as in send_option_arg_callback_request().
279 * \param f The same meaning as in send_option_arg_callback_request().
280 * \param result The same meaning as in send_option_arg_callback_request().
282 * This is similar to send_option_arg_callback_request(), but no options buffer
283 * is passed to the parent process.
285 * \return The return value of the underlying call to
286 * send_option_arg_callback_request().
288 int send_standard_callback_request(int argc, const char **argv,
289 callback_function *f, struct osl_object *result)
291 return send_option_arg_callback_request(NULL, argc, argv, f, result);
295 * write input from fd to dynamically allocated char array,
296 * but maximal max_size byte. Return size.
298 static int fd2buf(int fd, char **buf, int max_size)
300 const size_t chunk_size = 1024;
305 *buf = para_malloc(size * sizeof(char));
307 while ((ret = read(fd, p, chunk_size)) > 0) {
309 if ((p - *buf) + chunk_size >= size) {
313 if (size > max_size) {
314 ret = -E_INPUT_TOO_LARGE;
317 tmp = para_realloc(*buf, size);
318 p = (p - *buf) + tmp;
334 * Read from stdin, and send the result to the parent process.
336 * \param arg_obj Pointer to the arguments to \a f.
337 * \param f The callback function.
338 * \param max_len Don't read more than that many bytes from stdin.
339 * \param result The result of the query is stored here.
341 * This function is used by commands that wish to let para_server store
342 * arbitrary data specified by the user (for instance the add_blob family of
343 * commands). First, at most \a max_len bytes are read from stdin, the result
344 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
345 * is made available to the parent process via shared memory.
347 * \return Negative on errors, the return value of the underlying call to
348 * send_callback_request() otherwise.
350 int stdin_command(struct osl_object *arg_obj, callback_function *f,
351 unsigned max_len, struct osl_object *result)
355 struct osl_object query;
356 int ret = fd2buf(STDIN_FILENO, &stdin_buf, max_len);
361 query.size = arg_obj->size + stdin_len;
362 query.data = para_malloc(query.size);
363 memcpy(query.data, arg_obj->data, arg_obj->size);
364 memcpy((char *)query.data + arg_obj->size, stdin_buf, stdin_len);
366 ret = send_callback_request(f, &query, result);
372 * Open the audio file with highest score.
374 * \param afd Audio file data is returned here.
376 * This stores all information for streaming the "best" audio file
377 * in the \a afd structure.
379 * \return Positive on success, negative on errors.
381 * \sa close_audio_file(), open_and_update_audio_file().
383 int open_next_audio_file(struct audio_file_data *afd)
385 struct osl_row *aft_row;
388 ret = score_get_best(&aft_row, &afd->score);
391 ret = open_and_update_audio_file(aft_row, afd);
398 * Free all resources which were allocated by open_next_audio_file().
400 * \param afd The structure previously filled in by open_next_audio_file().
402 * \return The return value of the underlying call to para_munmap().
404 * \sa open_next_audio_file().
406 int close_audio_file(struct audio_file_data *afd)
408 free(afd->afhi.chunk_table);
409 return para_munmap(afd->map.data, afd->map.size);
413 static void play_loop(enum play_mode current_play_mode)
416 struct audio_file_data afd;
418 afd.current_play_mode = current_play_mode;
419 for (i = 0; i < 0; i++) {
420 ret = open_next_audio_file(&afd);
422 PARA_ERROR_LOG("failed to open next audio file: %d\n", ret);
425 PARA_NOTICE_LOG("next audio file: %s, score: %li\n", afd.path, afd.score);
427 close_audio_file(&afd);
433 static enum play_mode init_admissible_files(void)
436 char *given_mood, *given_playlist;
438 given_mood = "mood_that_was_given_at_the_command_line";
439 given_playlist = "given_playlist";
442 ret = mood_open(given_mood);
445 PARA_WARNING_LOG("ignoring playlist %s\n",
447 return PLAY_MODE_MOOD;
450 if (given_playlist) {
451 ret = playlist_open(given_playlist);
453 return PLAY_MODE_PLAYLIST;
455 ret = mood_open(NULL); /* open first available mood */
457 return PLAY_MODE_MOOD;
458 mood_open(""); /* open dummy mood, always successful */
459 return PLAY_MODE_MOOD;
464 static void setup_command_socket(void)
467 char *socket_name = "/tmp/afs_command_socket";
468 struct sockaddr_un unix_addr;
471 ret = create_local_socket(socket_name, &unix_addr,
472 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
475 command_socket = ret;
476 if (listen(command_socket , 5) < 0) {
477 PARA_EMERG_LOG("%s", "can not listen on socket\n");
480 PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
492 __noreturn int afs_init(uint32_t cookie, int socket_fd)
496 enum play_mode current_play_mode;
498 server_socket = socket_fd;
499 socket_cookie = cookie;
500 PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
501 server_socket, (unsigned) cookie);
502 setup_command_socket();
504 ret = attribute_init(&afs_tables[TBLNUM_ATTRIBUTES]);
506 goto attribute_init_error;
507 ret = moods_init(&afs_tables[TBLNUM_MOODS]);
509 goto moods_init_error;
510 ret = playlists_init(&afs_tables[TBLNUM_PLAYLIST]);
512 goto playlists_init_error;
513 ret = lyrics_init(&afs_tables[TBLNUM_LYRICS]);
515 goto lyrics_init_error;
516 ret = images_init(&afs_tables[TBLNUM_IMAGES]);
518 goto images_init_error;
519 ret = score_init(&afs_tables[TBLNUM_SCORES]);
521 goto score_init_error;
522 ret = aft_init(&afs_tables[TBLNUM_AUDIO_FILES]);
526 current_play_mode = init_admissible_files();
530 ret = shm_new(sizeof(struct callback_data));
534 ret = shm_attach(shmid, ATTACH_RW, &shm_area);
537 shm_callback_data = shm_area;
541 callback_mutex = ret;
550 mutex_lock(result_mutex);
553 score_shutdown(OSL_MARK_CLEAN);
555 images_shutdown(OSL_MARK_CLEAN);
557 lyrics_shutdown(OSL_MARK_CLEAN);
559 playlists_shutdown(OSL_MARK_CLEAN);
560 playlists_init_error:
561 moods_shutdown(OSL_MARK_CLEAN);
563 attribute_shutdown(OSL_MARK_CLEAN);
564 attribute_init_error:
568 static int create_all_tables(void)
572 for (i = 0; i < NUM_AFS_TABLES; i++) {
573 struct table_info *ti = afs_tables + i;
575 if (ti->flags & TBLFLAG_SKIP_CREATE)
577 ret = osl_create_table(ti->desc);
584 /* TODO load tables after init */
585 static int com_init(__a_unused int fd, int argc, const char **argv)
589 return create_all_tables();
590 for (i = 1; i < argc; i++) {
591 for (j = 0; j < NUM_AFS_TABLES; j++) {
592 struct table_info *ti = afs_tables + j;
594 if (ti->flags & TBLFLAG_SKIP_CREATE)
596 if (strcmp(argv[i], ti->desc->name))
598 PARA_NOTICE_LOG("creating table %s\n", argv[i]);
599 ret = osl_create_table(ti->desc);
604 if (j == NUM_AFS_TABLES)
605 return -E_BAD_TABLE_NAME;
609 /** Describes a command of para_server. */
611 /** The name of the command. */
613 /** The handler function. */
614 int (*handler)(int fd, int argc, const char **argv);
617 static struct command cmd[] = {
624 .handler = com_addlyr,
628 .handler = com_addimg,
632 .handler = com_addmood,
636 .handler = com_addpl,
640 .handler = com_catlyr,
644 .handler = com_catimg,
648 .handler = com_mvimg,
652 .handler = com_mvlyr,
656 .handler = com_mvmood,
664 .handler = com_catmood,
668 .handler = com_catpl,
672 .handler = com_rmatt,
680 .handler = com_lsatt,
684 .handler = com_afs_ls,
688 .handler = com_lslyr,
692 .handler = com_lsimg,
696 .handler = com_lsmood,
704 .handler = com_setatt,
708 .handler = com_addatt,
712 .handler = com_afs_rm,
716 .handler = com_rmlyr,
720 .handler = com_rmimg,
724 .handler = com_rmmood,
732 .handler = com_touch,
739 static void call_callback(void)
741 struct osl_object query, result = {.data = NULL};
744 shm_callback_data->result_shmid = -1; /* no result */
745 ret = shm_attach(shm_callback_data->query_shmid, ATTACH_RW,
749 query.size = shm_callback_data->query_size;
750 shm_callback_data->callback_ret = shm_callback_data->handler(&query,
752 if (result.data && result.size) {
754 ret = shm_new(result.size);
757 shm_callback_data->result_shmid = ret;
758 shm_callback_data->result_size = result.size;
759 ret = shm_attach(shm_callback_data->result_shmid, ATTACH_RW, &sma);
762 memcpy(sma, result.data, result.size);
763 ret = shm_detach(sma);
765 PARA_ERROR_LOG("detach result failed\n");
772 if (shm_destroy(shm_callback_data->result_shmid) < 0)
773 PARA_ERROR_LOG("destroy result failed\n");
774 shm_callback_data->result_shmid = -1;
777 ret2 = shm_detach(query.data);
779 PARA_ERROR_LOG("detach query failed\n");
785 PARA_ERROR_LOG("sma error %d\n", ret);
786 shm_callback_data->sma_ret = ret;
787 shm_callback_data->handler = NULL;
788 mutex_unlock(result_mutex); /* wake up child */
791 static void afs_shutdown(enum osl_close_flags flags)
793 score_shutdown(flags);
794 attribute_shutdown(flags);
797 moods_shutdown(flags);
798 playlists_shutdown(flags);
799 lyrics_shutdown(flags);
800 images_shutdown(flags);
805 static int got_sigchld;
806 static void server_loop(int child_pid)
810 PARA_DEBUG_LOG("server pid: %d, child pid: %d\n",
811 getpid(), child_pid);
813 mutex_lock(callback_mutex);
814 if (shm_callback_data->handler)
816 mutex_unlock(callback_mutex);
820 mutex_destroy(result_mutex);
821 mutex_destroy(callback_mutex);
822 mutex_destroy(child_mutex);
823 afs_shutdown(OSL_MARK_CLEAN);
828 int main(int argc, const char **argv)
830 int i, ret = -E_AFS_SYNTAX;
832 signal(SIGUSR1, dummy);
833 signal(SIGCHLD, sigchld_handler);
839 PARA_EMERG_LOG("afs_init returned %d\n", ret);
849 for (i = 0; cmd[i].name; i++) {
850 if (strcmp(cmd[i].name, argv[1]))
852 ret = cmd[i].handler(1, argc - 1 , argv + 1);
856 PARA_ERROR_LOG("unknown command: %s\n", argv[1]);
860 PARA_ERROR_LOG("error %d\n", ret);
862 PARA_DEBUG_LOG("%s", "success\n");
864 return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;