+ * \param argc The same meaning as in send_option_arg_callback_request().
+ * \param argv The same meaning as in send_option_arg_callback_request().
+ * \param f The same meaning as in send_option_arg_callback_request().
+ * \param result The same meaning as in send_option_arg_callback_request().
+ *
+ * This is similar to send_option_arg_callback_request(), but no options buffer
+ * is passed to the parent process.
+ *
+ * \return The return value of the underlying call to
+ * send_option_arg_callback_request().
+ */
+int send_standard_callback_request(int argc, char * const * const argv,
+ callback_function *f, struct osl_object *result)
+{
+ return send_option_arg_callback_request(NULL, argc, argv, f, result);
+}
+
+/**
+ * Compare two osl objects of string type.
+ *
+ * \param obj1 Pointer to the first object.
+ * \param obj2 Pointer to the second object.
+ *
+ * In any case, only \p MIN(obj1->size, obj2->size) characters of each string
+ * are taken into account.
+ *
+ * \return It returns an integer less than, equal to, or greater than zero if
+ * \a obj1 is found, respectively, to be less than, to match, or be greater than
+ * obj2.
+ *
+ * \sa strcmp(3), strncmp(3), osl_compare_func.
+ */
+int string_compare(const struct osl_object *obj1, const struct osl_object *obj2)
+{
+ const char *str1 = (const char *)obj1->data;
+ const char *str2 = (const char *)obj2->data;
+ return strncmp(str1, str2, PARA_MIN(obj1->size, obj2->size));
+}
+
+/**
+ * A wrapper for strtol(3).
+ *
+ * \param str The string to be converted to a long integer.
+ * \param result The converted value is stored here.
+ *
+ * \return Positive on success, -E_ATOL on errors.
+ *
+ * \sa strtol(3), atoi(3).
+ */
+int para_atol(const char *str, long *result)
+{
+ char *endptr;
+ long val;
+ int ret, base = 10;
+
+ errno = 0; /* To distinguish success/failure after call */
+ val = strtol(str, &endptr, base);
+ ret = -E_ATOL;
+ if (errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
+ goto out; /* overflow */
+ if (errno != 0 && val == 0)
+ goto out; /* other error */
+ if (endptr == str)
+ goto out; /* No digits were found */
+ if (*endptr != '\0')
+ goto out; /* Further characters after number */
+ *result = val;
+ ret = 1;
+out:
+ return ret;
+}
+
+
+/*
+ * write input from fd to dynamically allocated buffer,
+ * but maximal max_size byte.
+ */
+static int fd2buf(int fd, unsigned max_size, struct osl_object *obj)
+{
+ const size_t chunk_size = 1024;
+ size_t size = 2048, received = 0;
+ int ret;
+ char *buf = para_malloc(size);
+
+ for (;;) {
+ ret = recv_bin_buffer(fd, buf + received, chunk_size);
+ if (ret <= 0)
+ break;
+ received += ret;
+ if (received + chunk_size >= size) {
+ size *= 2;
+ ret = -E_INPUT_TOO_LARGE;
+ if (size > max_size)
+ break;
+ buf = para_realloc(buf, size);
+ }
+ }
+ obj->data = buf;
+ obj->size = received;
+ if (ret < 0)
+ free(buf);
+ return ret;
+}
+
+/**
+ * Read data from a file descriptor, and send it to the afs process.
+ *
+ * \param fd File descriptor to read data from.
+ * \param arg_obj Pointer to the arguments to \a f.
+ * \param f The callback function.
+ * \param max_len Don't read more than that many bytes from stdin.
+ * \param result The result of the query is stored here.
+ *
+ * This function is used by commands that wish to let para_server store
+ * arbitrary data specified by the user (for instance the add_blob family of
+ * commands). First, at most \a max_len bytes are read from \a fd, the result
+ * is concatenated with the buffer given by \a arg_obj, and the combined buffer
+ * is made available to the parent process via shared memory.
+ *
+ * \return Negative on errors, the return value of the underlying call to
+ * send_callback_request() otherwise.
+ */
+int stdin_command(int fd, struct osl_object *arg_obj, callback_function *f,
+ unsigned max_len, struct osl_object *result)
+{
+ struct osl_object query, stdin_obj;
+ int ret;
+
+ ret = send_buffer(fd, AWAITING_DATA_MSG);
+ if (ret < 0)
+ return ret;
+ ret = fd2buf(fd, max_len, &stdin_obj);
+ if (ret < 0)
+ return ret;
+ query.size = arg_obj->size + stdin_obj.size;
+ query.data = para_malloc(query.size);
+ memcpy(query.data, arg_obj->data, arg_obj->size);
+ memcpy((char *)query.data + arg_obj->size, stdin_obj.data, stdin_obj.size);
+ free(stdin_obj.data);
+ ret = send_callback_request(f, &query, result);
+ free(query.data);
+ return ret;
+}
+
+/**
+ * Open the audio file with highest score.
+ *
+ * \param afd Audio file data is returned here.
+ *
+ * This stores all information for streaming the "best" audio file
+ * in the \a afd structure.
+ *
+ * \return Positive on success, negative on errors.
+ *
+ * \sa close_audio_file(), open_and_update_audio_file().
+ */
+int open_next_audio_file(struct audio_file_data *afd)
+{
+ struct osl_row *aft_row;
+ int ret;
+ for (;;) {
+ ret = score_get_best(&aft_row, &afd->score);
+ if (ret < 0)
+ return ret;
+ ret = open_and_update_audio_file(aft_row, afd);
+ if (ret >= 0)
+ return ret;
+ }
+}
+
+/**
+ * Free all resources which were allocated by open_next_audio_file().
+ *
+ * \param afd The structure previously filled in by open_next_audio_file().
+ *
+ * \return The return value of the underlying call to para_munmap().
+ *
+ * \sa open_next_audio_file().
+ */
+int close_audio_file(struct audio_file_data *afd)
+{
+ free(afd->afhi.chunk_table);
+ return para_munmap(afd->map.data, afd->map.size);
+}
+
+#if 0
+static void play_loop(enum play_mode current_play_mode)
+{
+ int i, ret;
+ struct audio_file_data afd;
+
+ afd.current_play_mode = current_play_mode;
+ for (i = 0; i < 0; i++) {
+ ret = open_next_audio_file(&afd);
+ if (ret < 0) {
+ PARA_ERROR_LOG("failed to open next audio file: %d\n", ret);
+ return;
+ }
+ PARA_NOTICE_LOG("next audio file: %s, score: %li\n", afd.path, afd.score);
+ sleep(1);
+ close_audio_file(&afd);
+ }
+}
+#endif
+
+
+static enum play_mode init_admissible_files(void)
+{
+ int ret;
+ char *given_mood, *given_playlist;
+
+ given_mood = "mood_that_was_given_at_the_command_line";
+ given_playlist = "given_playlist";
+
+ if (given_mood) {
+ ret = mood_open(given_mood);
+ if (ret >= 0) {
+ if (given_playlist)
+ PARA_WARNING_LOG("ignoring playlist %s\n",
+ given_playlist);
+ return PLAY_MODE_MOOD;
+ }
+ }
+ if (given_playlist) {
+ ret = playlist_open(given_playlist);
+ if (ret >= 0)
+ return PLAY_MODE_PLAYLIST;
+ }
+ ret = mood_open(NULL); /* open first available mood */
+ if (ret >= 0)
+ return PLAY_MODE_MOOD;
+ mood_open(""); /* open dummy mood, always successful */
+ return PLAY_MODE_MOOD;
+}
+
+static int setup_command_socket_or_die(void)
+{
+ int ret;
+ char *socket_name = conf.afs_socket_arg;
+ struct sockaddr_un unix_addr;
+
+ unlink(socket_name);
+ ret = create_local_socket(socket_name, &unix_addr,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
+ if (ret < 0) {
+ PARA_EMERG_LOG("%s: %s\n", PARA_STRERROR(-ret), socket_name);
+ exit(EXIT_FAILURE);
+ }
+ if (listen(ret , 5) < 0) {
+ PARA_EMERG_LOG("%s", "can not listen on socket\n");
+ exit(EXIT_FAILURE);
+ }
+ PARA_INFO_LOG("listening on command socket %s (fd %d)\n", socket_name,
+ ret);
+ return ret;
+}
+
+static int server_socket;
+static struct command_task command_task_struct;
+static struct signal_task signal_task_struct;
+
+static void unregister_tasks(void)
+{
+ unregister_task(&command_task_struct.task);
+ unregister_task(&signal_task_struct.task);
+}
+
+static void close_afs_tables(enum osl_close_flags flags)
+{
+ PARA_NOTICE_LOG("closing afs_tables\n");
+ score_shutdown(flags);
+ attribute_shutdown(flags);
+ mood_close();
+ playlist_close();
+ moods_shutdown(flags);
+ playlists_shutdown(flags);
+ lyrics_shutdown(flags);
+ images_shutdown(flags);
+ aft_shutdown(flags);
+}
+
+static void signal_pre_select(struct sched *s, struct task *t)
+{
+ struct signal_task *st = t->private_data;
+ t->ret = 1;
+ para_fd_set(st->fd, &s->rfds, &s->max_fileno);
+}
+
+static void signal_post_select(struct sched *s, struct task *t)
+{
+ struct signal_task *st = t->private_data;
+ t->ret = 1;
+ if (!FD_ISSET(st->fd, &s->rfds))
+ return;
+ st->signum = para_next_signal();
+ t->ret = 1;
+ if (st->signum == SIGUSR1)
+ return; /* ignore SIGUSR1 */
+ PARA_NOTICE_LOG("caught signal %d\n", st->signum);
+ t->ret = -E_SIGNAL_CAUGHT;
+ unregister_tasks();
+}
+
+static void register_signal_task(void)
+{
+ struct signal_task *st = &signal_task_struct;
+ st->fd = para_signal_init();
+ PARA_INFO_LOG("signal pipe: fd %d\n", st->fd);
+ para_install_sighandler(SIGINT);
+ para_install_sighandler(SIGTERM);
+ para_install_sighandler(SIGPIPE);
+
+ st->task.pre_select = signal_pre_select;
+ st->task.post_select = signal_post_select;
+ st->task.private_data = st;
+ sprintf(st->task.status, "signal task");
+ register_task(&st->task);
+}
+
+static void command_pre_select(struct sched *s, struct task *t)
+{
+ struct command_task *ct = t->private_data;
+ t->ret = 1;
+ para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
+}
+
+/*
+ * On errors, negative value is written to fd.
+ * On success: If query produced a result, the result_shmid is written to fd.
+ * Otherwise, zero is written.