3 #include <dirent.h> /* readdir() */
13 /** \file afs.c Paraslash's audio file selector. */
16 * Compare two osl objects of string type.
18 * \param obj1 Pointer to the first object.
19 * \param obj2 Pointer to the second object.
21 * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
22 * are taken into account.
24 * \return It returns an integer less than, equal to, or greater than zero if
25 * \a obj1 is found, respectively, to be less than, to match, or be greater than
28 * \sa strcmp(3), strncmp(3), osl_compare_func.
30 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
32 const char *str1 = (const char *)obj1->data;
33 const char *str2 = (const char *)obj2->data;
34 return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
37 /** The osl tables used by afs. \sa blob.c */
39 /** Contains audio file information. See aft.c. */
41 /** The table for the paraslash attributes. See attribute.c. */
44 * Paraslash's scoring system is based on Gaussian normal
45 * distributions, and the relevant data is stored in the rbtrees of an
46 * osl table containing only volatile columns. See score.c for
51 * A standard blob table containing the mood definitions. For details
55 /** A blob table containing lyrics on a per-song basis. */
57 /** Another blob table for images (for example album cover art). */
59 /** Yet another blob table for storing standard playlists. */
61 /** How many tables are in use? */
65 static struct table_info afs_tables[NUM_AFS_TABLES];
69 * A wrapper for strtol(3).
71 * \param str The string to be converted to a long integer.
72 * \param result The converted value is stored here.
74 * \return Positive on success, -E_ATOL on errors.
76 * \sa strtol(3), atoi(3).
78 int para_atol(const char *str, long *result)
84 errno = 0; /* To distinguish success/failure after call */
85 val = strtol(str, &endptr, base);
87 if (errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
88 goto out; /* overflow */
89 if (errno != 0 && val == 0)
90 goto out; /* other error */
92 goto out; /* No digits were found */
94 goto out; /* Further characters after number */
102 * Struct to let para_server call a function specified from child context.
104 * Commands that need to change the state of para_server can't
105 * change the relevant data structures directly because commands
106 * are executed in a child process, i.e. they get their own
107 * virtual address space. This structure must be used to let
108 * para_server (i.e. the parent process) call a function specified
109 * by the child (the command handler).
111 * \sa fork(2), ipc.c.
113 struct callback_data {
114 /** The function to be called. */
115 callback_function *handler;
116 /** The sma for the parameters of the callback function. */
118 /** The size of the query sma. */
120 /** If the callback produced a result, it is stored in this sma. */
122 /** The size of the result sma. */
124 /** The return value of the callback function. */
126 /** The return value of the callback() procedure. */
130 static struct callback_data *shm_callback_data;
131 static int callback_mutex;
132 static int child_mutex;
133 static int result_mutex;
136 * Ask the parent process to call a given function.
138 * \param f The function to be called.
139 * \param query Pointer to arbitrary data for the callback.
140 * \param result Callback result will be stored here.
142 * This function creates a shared memory area, copies the buffer pointed to by
143 * \a buf to that area and notifies the parent process that \a f should be
144 * called ASAP. It provides proper locking via semaphores to protect against
145 * concurent access to the shared memory area and against concurrent access by
146 * another child process that asks to call the same function.
148 * \return Negative, if the shared memory area could not be set up. The return
149 * value of the callback function otherwise.
151 * \sa shm_new(), shm_attach(), shm_detach(), mutex_lock(), mutex_unlock(),
152 * shm_destroy(), struct callback_data, send_option_arg_callback_request(),
153 * send_standard_callback_request().
155 int send_callback_request(callback_function *f, struct osl_object *query,
156 struct osl_object *result)
158 struct callback_data cbd = {.handler = f};
162 assert(query->data && query->size);
163 ret = shm_new(query->size);
166 cbd.query_shmid = ret;
167 cbd.query_size = query->size;
168 ret = shm_attach(cbd.query_shmid, ATTACH_RW, &query_sma);
171 memcpy(query_sma, query->data, query->size);
172 ret = shm_detach(query_sma);
175 /* prevent other children from interacting */
176 mutex_lock(child_mutex);
177 /* prevent parent from messing with shm_callback_data. */
178 mutex_lock(callback_mutex);
179 /* all three mutexes are locked, set parameters for callback */
180 *shm_callback_data = cbd;
182 mutex_unlock(callback_mutex);
183 kill(getppid(), SIGUSR1); /* wake up parent */
185 * At this time only the parent can run. It will execute our callback
186 * and unlock the result_mutex when ready to indicate that the child
187 * may use the result. So let's sleep on this mutex.
189 mutex_lock(result_mutex);
190 /* No need to aquire the callback mutex again */
191 ret = shm_callback_data->sma_ret;
192 if (ret < 0) /* sma problem, callback might not have been executed */
193 goto unlock_child_mutex;
194 if (shm_callback_data->result_shmid >= 0) { /* parent provided a result */
196 ret = shm_attach(shm_callback_data->result_shmid, ATTACH_RO,
199 if (result) { /* copy result */
200 result->size = shm_callback_data->result_size;
201 result->data = para_malloc(result->size);
202 memcpy(result->data, sma, result->size);
203 ret = shm_detach(sma);
205 PARA_ERROR_LOG("can not detach result\n");
207 PARA_WARNING_LOG("no result pointer\n");
209 PARA_ERROR_LOG("attach result failed: %d\n", ret);
210 if (shm_destroy(shm_callback_data->result_shmid) < 0)
211 PARA_ERROR_LOG("destroy result failed\n");
212 } else { /* no result from callback */
214 PARA_WARNING_LOG("callback has no result\n");
219 ret = shm_callback_data->callback_ret;
221 /* give other children a chance */
222 mutex_unlock(child_mutex);
224 if (shm_destroy(cbd.query_shmid) < 0)
225 PARA_ERROR_LOG("%s\n", "shm destroy error");
226 PARA_DEBUG_LOG("callback_ret: %d\n", ret);
231 * Send a callback request passing an options structure and an argument vector.
233 * \param options pointer to an arbitrary data structure.
234 * \param argc Argument count.
235 * \param argv Standard argument vector.
236 * \param f The callback function.
237 * \param result The result of the query is stored here.
239 * Some commands have a couple of options that are parsed in child context for
240 * syntactic correctness and are stored in a special options structure for that
241 * command. This function allows to pass such a structure together with a list
242 * of further arguments (often a list of audio files) to the parent process.
244 * \sa send_standard_callback_request(), send_callback_request().
246 int send_option_arg_callback_request(struct osl_object *options,
247 int argc, const char **argv, callback_function *f,
248 struct osl_object *result)
252 struct osl_object query = {.size = options? options->size : 0};
254 for (i = 0; i < argc; i++)
255 query.size += strlen(argv[i]) + 1;
256 query.data = para_malloc(query.size);
259 memcpy(query.data, options->data, options->size);
262 for (i = 0; i < argc; i++) {
263 strcpy(p, argv[i]); /* OK */
264 p += strlen(argv[i]) + 1;
266 ret = send_callback_request(f, &query, result);
272 * Send a callback request with an argument vector only.
274 * \param argc The same meaning as in send_option_arg_callback_request().
275 * \param argv The same meaning as in send_option_arg_callback_request().
276 * \param f The same meaning as in send_option_arg_callback_request().
277 * \param result The same meaning as in send_option_arg_callback_request().
279 * This is similar to send_option_arg_callback_request(), but no options buffer
280 * is passed to the parent process.
282 * \return The return value of the underlying call to
283 * send_option_arg_callback_request().
285 int send_standard_callback_request(int argc, const char **argv,
286 callback_function *f, struct osl_object *result)
288 return send_option_arg_callback_request(NULL, argc, argv, f, result);
292 * write input from fd to dynamically allocated char array,
293 * but maximal max_size byte. Return size.
295 static int fd2buf(int fd, char **buf, int max_size)
297 const size_t chunk_size = 1024;
302 *buf = para_malloc(size * sizeof(char));
304 while ((ret = read(fd, p, chunk_size)) > 0) {
306 if ((p - *buf) + chunk_size >= size) {
310 if (size > max_size) {
311 ret = -E_INPUT_TOO_LARGE;
314 tmp = para_realloc(*buf, size);
315 p = (p - *buf) + tmp;
331 * Read from stdin, and send the result to the parent process.
333 * \param arg_obj Pointer to the arguments to \a f.
334 * \param f The callback function.
335 * \param max_len Don't read more than that many bytes from stdin.
336 * \param result The result of the query is stored here.
338 * This function is used by commands that wish to let para_server store
339 * arbitrary data specified by the user (for instance the add_blob family of
340 * commands). First, at most \a max_len bytes are read from stdin, the result
341 * is concatenated with the buffer given by \a arg_obj, and the combined buffer
342 * is made available to the parent process via shared memory.
344 * \return Negative on errors, the return value of the underlying call to
345 * send_callback_request() otherwise.
347 int stdin_command(struct osl_object *arg_obj, callback_function *f,
348 unsigned max_len, struct osl_object *result)
352 struct osl_object query;
353 int ret = fd2buf(STDIN_FILENO, &stdin_buf, max_len);
358 query.size = arg_obj->size + stdin_len;
359 query.data = para_malloc(query.size);
360 memcpy(query.data, arg_obj->data, arg_obj->size);
361 memcpy((char *)query.data + arg_obj->size, stdin_buf, stdin_len);
363 ret = send_callback_request(f, &query, result);
368 static void para_init_random_seed(void)
373 gettimeofday(&now, NULL);
379 * Open the audio file with highest score.
381 * \param afd Audio file data is returned here.
383 * This stores all information for streaming the "best" audio file
384 * in the \a afd structure.
386 * \return Positive on success, negative on errors.
388 * \sa close_audio_file(), open_and_update_audio_file().
390 int open_next_audio_file(struct audio_file_data *afd)
392 struct osl_row *aft_row;
395 ret = score_get_best(&aft_row, &afd->score);
398 ret = open_and_update_audio_file(aft_row, afd);
405 * Free all resources which were allocated by open_next_audio_file().
407 * \param afd The structure previously filled in by open_next_audio_file().
409 * \return The return value of the underlying call to para_munmap().
411 * \sa open_next_audio_file().
413 int close_audio_file(struct audio_file_data *afd)
415 free(afd->afhi.chunk_table);
416 return para_munmap(afd->map.data, afd->map.size);
419 static void play_loop(enum play_mode current_play_mode)
422 struct audio_file_data afd;
424 afd.current_play_mode = current_play_mode;
425 for (i = 0; i < 0; i++) {
426 ret = open_next_audio_file(&afd);
428 PARA_ERROR_LOG("failed to open next audio file: %d\n", ret);
431 PARA_NOTICE_LOG("next audio file: %s, score: %li\n", afd.path, afd.score);
433 close_audio_file(&afd);
437 static enum play_mode init_admissible_files(void)
440 char *given_mood, *given_playlist;
442 given_mood = "mood_that_was_given_at_the_command_line";
443 given_playlist = "given_playlist";
446 ret = mood_open(given_mood);
449 PARA_WARNING_LOG("ignoring playlist %s\n",
451 return PLAY_MODE_MOOD;
454 if (given_playlist) {
455 ret = playlist_open(given_playlist);
457 return PLAY_MODE_PLAYLIST;
459 ret = mood_open(NULL); /* open first available mood */
461 return PLAY_MODE_MOOD;
462 mood_open(""); /* open dummy mood, always successful */
463 return PLAY_MODE_MOOD;
466 static int afs_init(void)
470 enum play_mode current_play_mode;
472 para_init_random_seed();
474 ret = attribute_init(&afs_tables[TBLNUM_ATTRIBUTES]);
475 PARA_DEBUG_LOG("ret %d\n", ret);
478 ret = moods_init(&afs_tables[TBLNUM_MOODS]);
480 goto moods_init_error;
481 ret = playlists_init(&afs_tables[TBLNUM_PLAYLIST]);
483 goto playlists_init_error;
484 ret = lyrics_init(&afs_tables[TBLNUM_LYRICS]);
486 goto lyrics_init_error;
487 ret = images_init(&afs_tables[TBLNUM_IMAGES]);
489 goto images_init_error;
490 ret = score_init(&afs_tables[TBLNUM_SCORES]);
492 goto score_init_error;
493 ret = aft_init(&afs_tables[TBLNUM_AUDIO_FILES]);
497 current_play_mode = init_admissible_files();
498 play_loop(current_play_mode);
500 ret = shm_new(sizeof(struct callback_data));
504 ret = shm_attach(shmid, ATTACH_RW, &shm_area);
507 shm_callback_data = shm_area;
511 callback_mutex = ret;
520 mutex_lock(result_mutex);
523 score_shutdown(OSL_MARK_CLEAN);
525 images_shutdown(OSL_MARK_CLEAN);
527 lyrics_shutdown(OSL_MARK_CLEAN);
529 playlists_shutdown(OSL_MARK_CLEAN);
530 playlists_init_error:
531 moods_shutdown(OSL_MARK_CLEAN);
533 attribute_shutdown(OSL_MARK_CLEAN);
537 static uint32_t afs_socket_cookie;
538 static int para_random(unsigned max)
540 return ((max + 0.0) * (rand() / (RAND_MAX + 1.0)));
545 int ret, afs_server_socket[2];
547 para_init_random_seed();
548 ret = socketpair(PF_UNIX, SOCK_DGRAM, 0, afs_server_socket);
551 afs_socket_cookie = para_random((uint32_t)-1);
555 if (!ret) { /* child (afs) */
556 char *socket_name = "/tmp/afs_command_socket";
557 struct sockaddr_un unix_addr;
561 ret = create_local_socket(socket_name, &unix_addr,
562 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
566 if (listen(fd , 5) < 0) {
567 PARA_EMERG_LOG("%s", "can not listen on socket\n");
573 PARA_NOTICE_LOG("accepting\n");
574 ret = para_accept(fd, &unix_addr, sizeof(struct sockaddr_un));
580 if (!ret) { /* child (handler) */
581 PARA_NOTICE_LOG("reading stdin\n");
585 PARA_NOTICE_LOG("read: %s\n", buf);
591 PARA_NOTICE_LOG("sending next requerst\n");
596 static int create_all_tables(void)
600 for (i = 0; i < NUM_AFS_TABLES; i++) {
601 struct table_info *ti = afs_tables + i;
603 if (ti->flags & TBLFLAG_SKIP_CREATE)
605 ret = osl_create_table(ti->desc);
612 /* TODO load tables after init */
613 static int com_init(__a_unused int fd, int argc, const char **argv)
617 return create_all_tables();
618 for (i = 1; i < argc; i++) {
619 for (j = 0; j < NUM_AFS_TABLES; j++) {
620 struct table_info *ti = afs_tables + j;
622 if (ti->flags & TBLFLAG_SKIP_CREATE)
624 if (strcmp(argv[i], ti->desc->name))
626 PARA_NOTICE_LOG("creating table %s\n", argv[i]);
627 ret = osl_create_table(ti->desc);
632 if (j == NUM_AFS_TABLES)
633 return -E_BAD_TABLE_NAME;
637 /** Describes a command of para_server. */
639 /** The name of the command. */
641 /** The handler function. */
642 int (*handler)(int fd, int argc, const char **argv);
645 static struct command cmd[] = {
652 .handler = com_addlyr,
656 .handler = com_addimg,
660 .handler = com_addmood,
664 .handler = com_addpl,
668 .handler = com_catlyr,
672 .handler = com_catimg,
676 .handler = com_mvimg,
680 .handler = com_mvlyr,
684 .handler = com_mvmood,
692 .handler = com_catmood,
696 .handler = com_catpl,
700 .handler = com_rmatt,
708 .handler = com_lsatt,
712 .handler = com_afs_ls,
716 .handler = com_lslyr,
720 .handler = com_lsimg,
724 .handler = com_lsmood,
732 .handler = com_setatt,
736 .handler = com_addatt,
740 .handler = com_afs_rm,
744 .handler = com_rmlyr,
748 .handler = com_rmimg,
752 .handler = com_rmmood,
760 .handler = com_touch,
767 static void call_callback(void)
769 struct osl_object query, result = {.data = NULL};
772 shm_callback_data->result_shmid = -1; /* no result */
773 ret = shm_attach(shm_callback_data->query_shmid, ATTACH_RW,
777 query.size = shm_callback_data->query_size;
778 shm_callback_data->callback_ret = shm_callback_data->handler(&query,
780 if (result.data && result.size) {
782 ret = shm_new(result.size);
785 shm_callback_data->result_shmid = ret;
786 shm_callback_data->result_size = result.size;
787 ret = shm_attach(shm_callback_data->result_shmid, ATTACH_RW, &sma);
790 memcpy(sma, result.data, result.size);
791 ret = shm_detach(sma);
793 PARA_ERROR_LOG("detach result failed\n");
800 if (shm_destroy(shm_callback_data->result_shmid) < 0)
801 PARA_ERROR_LOG("destroy result failed\n");
802 shm_callback_data->result_shmid = -1;
805 ret2 = shm_detach(query.data);
807 PARA_ERROR_LOG("detach query failed\n");
813 PARA_ERROR_LOG("sma error %d\n", ret);
814 shm_callback_data->sma_ret = ret;
815 shm_callback_data->handler = NULL;
816 mutex_unlock(result_mutex); /* wake up child */
819 static void dummy(__a_unused int s)
822 static void afs_shutdown(enum osl_close_flags flags)
824 score_shutdown(flags);
825 attribute_shutdown(flags);
828 moods_shutdown(flags);
829 playlists_shutdown(flags);
830 lyrics_shutdown(flags);
831 images_shutdown(flags);
835 static int got_sigchld;
836 static void sigchld_handler(__a_unused int s)
841 static void server_loop(int child_pid)
845 PARA_DEBUG_LOG("server pid: %d, child pid: %d\n",
846 getpid(), child_pid);
848 mutex_lock(callback_mutex);
849 if (shm_callback_data->handler)
851 mutex_unlock(callback_mutex);
855 mutex_destroy(result_mutex);
856 mutex_destroy(callback_mutex);
857 mutex_destroy(child_mutex);
858 afs_shutdown(OSL_MARK_CLEAN);
864 int main(int argc, const char **argv)
866 int i, ret = -E_AFS_SYNTAX;
868 signal(SIGUSR1, dummy);
869 signal(SIGCHLD, sigchld_handler);
875 PARA_EMERG_LOG("afs_init returned %d\n", ret);
885 for (i = 0; cmd[i].name; i++) {
886 if (strcmp(cmd[i].name, argv[1]))
888 ret = cmd[i].handler(1, argc - 1 , argv + 1);
892 PARA_ERROR_LOG("unknown command: %s\n", argv[1]);
896 PARA_ERROR_LOG("error %d\n", ret);
898 PARA_DEBUG_LOG("%s", "success\n");
900 return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;