/*
- * Copyright (C) 2007-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2007-2009 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
struct task task;
};
+extern int mmd_mutex;
extern struct misc_meta_data *mmd;
static int server_socket;
size_t result_size;
};
+static int dispatch_result(int result_shmid, callback_result_handler *handler,
+ void *private_result_data)
+{
+ struct osl_object result;
+ void *result_shm;
+ int ret2, ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
+ struct callback_result *cr = result_shm;
+
+ if (ret < 0) {
+ PARA_ERROR_LOG("attach failed: %s\n", para_strerror(-ret));
+ return ret;
+ }
+ result.size = cr->result_size;
+ result.data = result_shm + sizeof(*cr);
+ if (result.size) {
+ assert(handler);
+ ret = handler(&result, private_result_data);
+ if (ret < 0)
+ PARA_NOTICE_LOG("result handler error: %s\n",
+ para_strerror(-ret));
+ }
+ ret2 = shm_detach(result_shm);
+ if (ret2 < 0) {
+ PARA_ERROR_LOG("detach failed: %s\n", para_strerror(-ret2));
+ if (ret >= 0)
+ ret = ret2;
+ }
+ return ret;
+}
+
/**
* Ask the afs process to call a given function.
*
* \param f The function to be called.
* \param query Pointer to arbitrary data for the callback.
- * \param result Callback result will be stored here.
+ * \param result_handler Called for each shm area sent by the callback.
+ * \param private_result_data Passed verbatim to \a result_handler.
*
- * This function creates a shared memory area, copies the buffer pointed to by
- * \a query to that area and notifies the afs process that \a f should be
- * called ASAP.
+ * This function creates a socket for communication with the afs process and a
+ * shared memory area (sma) to which the buffer pointed to by \a query is
+ * copied. It then notifies the afs process that the callback function \a f
+ * should be executed by sending the shared memory identifier (shmid) to the
+ * socket.
+
+ * If the callback produces a result, it sends any number of shared memory
+ * identifiers back via the socket. For each such identifier received, \a
+ * result_handler is called. The contents of the sma identified by the received
+ * shmid are passed to that function as an osl object. The private_result_data
+ * pointer is passed as the second argument to \a result_handler.
*
- * \return Negative, on errors, the return value of the callback function
- * otherwise.
+ * \return Standard.
*
* \sa send_option_arg_callback_request(), send_standard_callback_request().
*/
void *private_result_data)
{
struct callback_query *cq;
- int num_results = 0, ret, fd = -1, query_shmid, result_shmid;
- void *query_shm, *result_shm;
+ int ret, fd = -1, query_shmid, result_shmid;
+ void *query_shm;
char buf[sizeof(afs_socket_cookie) + sizeof(int)];
size_t query_shm_size = sizeof(*cq);
+ int dispatch_error = 0;
if (query)
query_shm_size += query->size;
ret = send_bin_buffer(fd, buf, sizeof(buf));
if (ret < 0)
goto out;
+ /*
+ * Read all shmids from afs.
+ *
+ * Even if the dispatcher returns an error we _must_ continue to read
+ * shmids from fd so that we can destroy all shared memory areas that
+ * have been created for us by the afs process.
+ */
for (;;) {
ret = recv_bin_buffer(fd, buf, sizeof(int));
if (ret <= 0)
goto out;
- if (ret != sizeof(int)) {
- ret = -E_AFS_SHORT_READ;
- goto out;
- }
+ assert(ret == sizeof(int));
ret = *(int *) buf;
- if (ret <= 0)
- goto out;
+ assert(ret > 0);
result_shmid = ret;
- ret = shm_attach(result_shmid, ATTACH_RO, &result_shm);
- if (ret >= 0) {
- struct callback_result *cr = result_shm;
- struct osl_object result;
- num_results++;
- result.size = cr->result_size;
- result.data = result_shm + sizeof(*cr);
- if (result.size) {
- assert(result_handler);
- ret = result_handler(&result, private_result_data);
- if (shm_detach(result_shm) < 0)
- PARA_ERROR_LOG("can not detach result\n");
- }
- } else
- PARA_ERROR_LOG("attach result failed: %d\n", ret);
- if (shm_destroy(result_shmid) < 0)
- PARA_ERROR_LOG("destroy result failed\n");
+ if (!dispatch_error) {
+ ret = dispatch_result(result_shmid, result_handler,
+ private_result_data);
+ if (ret < 0)
+ dispatch_error = 1;
+ }
+ ret = shm_destroy(result_shmid);
if (ret < 0)
- break;
+ PARA_CRIT_LOG("destroy result failed: %s\n",
+ para_strerror(-ret));
}
out:
if (shm_destroy(query_shmid) < 0)
- PARA_ERROR_LOG("%s\n", "shm destroy error");
+ PARA_CRIT_LOG("shm destroy error\n");
if (fd >= 0)
close(fd);
- if (ret >= 0)
- ret = num_results;
// PARA_DEBUG_LOG("callback_ret: %d\n", ret);
return ret;
}
* \param argc Argument count.
* \param argv Standard argument vector.
* \param f The callback function.
- * \param result The result of the query is stored here.
+ * \param result_handler See \ref send_callback_request.
+ * \param private_result_data See \ref send_callback_request.
*
* Some commands have a couple of options that are parsed in child context for
* syntactic correctness and are stored in a special options structure for that
* \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().
+ * \param result_handler See \ref send_callback_request.
+ * \param private_result_data See \ref send_callback_request.
*
* This is similar to send_option_arg_callback_request(), but no options buffer
* is passed to the parent process.
* \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.
+ * \param result_handler See \ref send_callback_request.
+ * \param private_result_data See \ref send_callback_request.
*
* 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.
+ * is made available to the afs process via the callback method. See \ref
+ * send_callback_request for details.
*
* \return Negative on errors, the return value of the underlying call to
* send_callback_request() otherwise.
*
* \sa open_and_update_audio_file().
*/
-int open_next_audio_file(void)
+static int open_next_audio_file(void)
{
struct osl_row *aft_row;
struct audio_file_data afd;
free(current_mop);
if (arg) {
current_mop = para_strdup(arg);
- mmd_lock();
+ mutex_lock(mmd_mutex);
strncpy(mmd->afs_mode_string, arg,
sizeof(mmd->afs_mode_string));
mmd->afs_mode_string[sizeof(mmd->afs_mode_string) - 1] = '\0';
- mmd_unlock();
+ mutex_unlock(mmd_mutex);
} else {
- mmd_lock();
+ mutex_lock(mmd_mutex);
strcpy(mmd->afs_mode_string, "dummy");
- mmd_unlock();
+ mutex_unlock(mmd_mutex);
current_mop = NULL;
}
}
free(pb.buf);
}
-int send_result(struct osl_object *result, void *private_result_data)
+/**
+ * Result handler for sending data to the para_client process.
+ *
+ * \param result The data to be sent.
+ * \param fd_ptr Pointer to the file descriptor.
+ *
+ * \return The return value of the underlying call to send_bin_buffer().
+ *
+ * \sa \ref callback_result_handler.
+ */
+int send_result(struct osl_object *result, void *fd_ptr)
{
- int fd = *(int *)private_result_data;
+ int fd = *(int *)fd_ptr;
if (!result->size)
return 1;
return send_bin_buffer(fd, result->data, result->size);
return ret;
}
-static void unregister_tasks(void)
-{
- unregister_task(&command_task_struct.task);
- unregister_task(&signal_task_struct.task);
-}
-
static void signal_pre_select(struct sched *s, struct task *t)
{
- struct signal_task *st = t->private_data;
- t->ret = 1;
+ struct signal_task *st = container_of(t, struct signal_task, task);
para_fd_set(st->fd, &s->rfds, &s->max_fileno);
}
-static void signal_post_select(struct sched *s, struct task *t)
+static void afs_signal_post_select(struct sched *s, struct task *t)
{
- struct signal_task *st = t->private_data;
- t->ret = -E_AFS_PARENT_DIED;
- if (getppid() == 1)
- goto err;
- t->ret = 1;
+ struct signal_task *st = container_of(t, struct signal_task, task);
+ if (getppid() == 1) {
+ PARA_EMERG_LOG("para_server died\n");
+ goto shutdown;
+ }
if (!FD_ISSET(st->fd, &s->rfds))
return;
st->signum = para_next_signal();
- t->ret = 1;
- if (st->signum == SIGUSR1)
- return; /* ignore SIGUSR1 */
if (st->signum == SIGHUP) {
close_afs_tables();
- t->ret = open_afs_tables();
- if (t->ret < 0)
- goto err;
+ parse_config_or_die(1);
+ t->error = open_afs_tables();
+ if (t->error < 0)
+ return;
init_admissible_files(current_mop);
return;
}
- t->ret = -E_AFS_SIGNAL;
-err:
- PARA_NOTICE_LOG("%s\n", para_strerror(-t->ret));
- unregister_tasks();
+ PARA_EMERG_LOG("terminating on signal %d\n", st->signum);
+shutdown:
+ sched_shutdown();
+ t->error = -E_AFS_SIGNAL;
}
static void register_signal_task(void)
{
struct signal_task *st = &signal_task_struct;
+
+ para_sigaction(SIGPIPE, SIG_IGN);
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);
para_install_sighandler(SIGHUP);
st->task.pre_select = signal_pre_select;
- st->task.post_select = signal_post_select;
- st->task.private_data = st;
+ st->task.post_select = afs_signal_post_select;
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;
+ struct command_task *ct = container_of(t, struct command_task, task);
struct afs_client *client;
para_fd_set(server_socket, &s->rfds, &s->max_fileno);
para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
list_for_each_entry(client, &afs_client_list, node)
para_fd_set(client->fd, &s->rfds, &s->max_fileno);
- t->ret = 1;
}
-int pass_buffer_as_shm(char *buf, size_t size, void *private_data)
+/**
+ * Send data as shared memory to a file descriptor.
+ *
+ * \param buf The buffer holding the data to be sent.
+ * \param size The size of \a buf.
+ * \param fd_ptr A pointer to the file descriptor.
+ *
+ * This function is used as the \a max_size handler in a \ref para_buffer
+ * structure. If used this way, it is called by \ref para_printf() whenever
+ * the buffer passed to para_printf() is about to exceed its maximal size.
+ *
+ * This function creates a shared memory area large enough to hold
+ * the content given by \a buf and \a size and sends the identifier
+ * of this area to the file descriptor given by \a fd_ptr.
+ *
+ * \return Zero if \a buf is \p NULL or \a size is zero. Negative on errors,
+ * and positive on success.
+ */
+int pass_buffer_as_shm(char *buf, size_t size, void *fd_ptr)
{
- int ret, shmid, fd = *(int *)private_data;
+ int ret, shmid, fd = *(int *)fd_ptr;
void *shm;
struct callback_result *cr;
query.data = (char *)query_shm + sizeof(*cq);
query.size = cq->query_size;
cq->handler(fd, &query);
- return 1;
+ return shm_detach(query_shm);
}
-static void execute_server_command(void)
+static int execute_server_command(void)
{
char buf[8];
int ret = recv_bin_buffer(server_socket, buf, sizeof(buf) - 1);
if (ret <= 0) {
- if (ret < 0)
- PARA_ERROR_LOG("%s\n", para_strerror(-ret));
- return;
+ if (!ret)
+ ret = -ERRNO_TO_PARA_ERROR(ECONNRESET);
+ goto err;
}
buf[ret] = '\0';
PARA_DEBUG_LOG("received: %s\n", buf);
- if (!strcmp(buf, "new")) {
- ret = open_next_audio_file();
- if (ret < 0) {
- PARA_EMERG_LOG("%s\n", para_strerror(-ret));
- unregister_tasks();
- }
- return;
- }
- PARA_ERROR_LOG("unknown command\n");
-
+ ret = -E_BAD_CMD;
+ if (strcmp(buf, "new"))
+ goto err;
+ ret = open_next_audio_file();
+err:
+ return ret;
}
static void execute_afs_command(int fd, uint32_t expected_cookie)
static void command_post_select(struct sched *s, struct task *t)
{
- struct command_task *ct = t->private_data;
+ struct command_task *ct = container_of(t, struct command_task, task);
struct sockaddr_un unix_addr;
struct afs_client *client, *tmp;
- int fd;
- if (FD_ISSET(server_socket, &s->rfds))
- execute_server_command();
+ int fd, ret;
+
+ if (FD_ISSET(server_socket, &s->rfds)) {
+ ret = execute_server_command();
+ if (ret < 0) {
+ PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+ sched_shutdown();
+ return;
+ }
+ }
/* Check the list of connected clients. */
list_for_each_entry_safe(client, tmp, &afs_client_list, node) {
}
/* Accept connections on the local socket. */
if (!FD_ISSET(ct->fd, &s->rfds))
- goto out;
- t->ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
- if (t->ret < 0) {
- PARA_NOTICE_LOG("%s\n", para_strerror(-t->ret));
- goto out;
+ return;
+ ret = para_accept(ct->fd, &unix_addr, sizeof(unix_addr));
+ if (ret < 0) {
+ PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
+ return;
}
- fd = t->ret;
- t->ret = mark_fd_nonblocking(fd);
- if (t->ret < 0) {
- PARA_NOTICE_LOG("%s\n", para_strerror(-t->ret));
+ fd = ret;
+ ret = mark_fd_nonblocking(fd);
+ if (ret < 0) {
+ PARA_NOTICE_LOG("%s\n", para_strerror(-ret));
close(fd);
- goto out;
+ return;
}
client = para_malloc(sizeof(*client));
client->fd = fd;
client->connect_time = *now;
para_list_add(&client->node, &afs_client_list);
-out:
- t->ret = 1;
}
static void register_command_task(uint32_t cookie)
ct->task.pre_select = command_pre_select;
ct->task.post_select = command_post_select;
- ct->task.private_data = ct;
sprintf(ct->task.status, "command task");
register_task(&ct->task);
}
-static void register_tasks(uint32_t cookie)
-{
- register_signal_task();
- register_command_task(cookie);
-}
-
/**
* Initialize the audio file selector process.
*
*/
__noreturn void afs_init(uint32_t cookie, int socket_fd)
{
- struct sched s;
+ static struct sched s;
int i, ret;
+ register_signal_task();
INIT_LIST_HEAD(&afs_client_list);
for (i = 0; i < NUM_AFS_TABLES; i++)
afs_tables[i].init(&afs_tables[i]);
ret = open_afs_tables();
-
- if (ret < 0) {
- PARA_EMERG_LOG("%s\n", para_strerror(-ret));
- exit(EXIT_FAILURE);
- }
+ if (ret < 0)
+ goto out;
server_socket = socket_fd;
ret = mark_fd_nonblocking(server_socket);
if (ret < 0)
- exit(EXIT_FAILURE);
+ goto out_close;
PARA_INFO_LOG("server_socket: %d, afs_socket_cookie: %u\n",
server_socket, (unsigned) cookie);
init_admissible_files(conf.afs_initial_mode_arg);
- register_tasks(cookie);
+ register_command_task(cookie);
s.default_timeout.tv_sec = 0;
s.default_timeout.tv_usec = 999 * 1000;
ret = schedule(&s);
+out_close:
+ close_afs_tables();
+out:
if (ret < 0)
PARA_EMERG_LOG("%s\n", para_strerror(-ret));
- close_afs_tables();
exit(EXIT_FAILURE);
}
return -E_BAD_TABLE_NAME;
}
}
- ret = send_callback_request(create_tables_callback, &query, NULL, NULL);
+ ret = send_callback_request(create_tables_callback, &query, &send_result, &fd);
if (ret < 0)
return send_va_buffer(fd, "%s\n", para_strerror(-ret));
return ret;
return 1;
}
+/**
+ * The afs event dispatcher.
+ *
+ * \param event Type of the event.
+ * \param pb May be \p NULL.
+ * \param data Type depends on \a event.
+ *
+ * This function calls the table handlers of all tables and passes \a pb and \a
+ * data verbatim. It's up to the handlers to interpret the \a data pointer.
+ */
void afs_event(enum afs_events event, struct para_buffer *pb,
void *data)
{
continue;
ret = t->event_handler(event, pb, data);
if (ret < 0)
- PARA_CRIT_LOG("%s\n", para_strerror(-ret));
+ PARA_CRIT_LOG("table %s, event %d: %s\n", t->name,
+ event, para_strerror(-ret));
}
}