seq_clientmgr.c

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/*
 * query next client
 */
static int snd_seq_ioctl_query_next_client(client_t *client, void __user *arg)
{
	client_t *cptr = NULL;
	snd_seq_client_info_t info;

	if (copy_from_user(&info, arg, sizeof(info)))
		return -EFAULT;

	/* search for next client */
	info.client++;
	if (info.client < 0)
		info.client = 0;
	for (; info.client < SNDRV_SEQ_MAX_CLIENTS; info.client++) {
		cptr = snd_seq_client_use_ptr(info.client);
		if (cptr)
			break; /* found */
	}
	if (cptr == NULL)
		return -ENOENT;

	get_client_info(cptr, &info);
	snd_seq_client_unlock(cptr);

	if (copy_to_user(arg, &info, sizeof(info)))
		return -EFAULT;
	return 0;
}

/* 
 * query next port
 */
static int snd_seq_ioctl_query_next_port(client_t *client, void __user *arg)
{
	client_t *cptr;
	client_port_t *port = NULL;
	snd_seq_port_info_t info;

	if (copy_from_user(&info, arg, sizeof(info)))
		return -EFAULT;
	cptr = snd_seq_client_use_ptr(info.addr.client);
	if (cptr == NULL)
		return -ENXIO;

	/* search for next port */
	info.addr.port++;
	port = snd_seq_port_query_nearest(cptr, &info);
	if (port == NULL) {
		snd_seq_client_unlock(cptr);
		return -ENOENT;
	}

	/* get port info */
	info.addr = port->addr;
	snd_seq_get_port_info(port, &info);
	snd_seq_port_unlock(port);
	snd_seq_client_unlock(cptr);

	if (copy_to_user(arg, &info, sizeof(info)))
		return -EFAULT;
	return 0;
}

/* -------------------------------------------------------- */

static struct seq_ioctl_table {
	unsigned int cmd;
	int (*func)(client_t *client, void __user * arg);
} ioctl_tables[] = {
	{ SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
	{ SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
	{ SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
	{ SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
	{ SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
	{ SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
	{ SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
	{ SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
	{ SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
	{ SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
	{ SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
	{ SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
	{ SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
	{ SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
	{ SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
	{ SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
	{ SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
	{ SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
	{ SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
	{ SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
	{ SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
	{ SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
	{ SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
	{ SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
	{ SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
	{ SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
	{ 0, NULL },
};

static int snd_seq_do_ioctl(client_t *client, unsigned int cmd, void __user *arg)
{
	struct seq_ioctl_table *p;

	switch (cmd) {
	case SNDRV_SEQ_IOCTL_PVERSION:
		/* return sequencer version number */
		return put_user(SNDRV_SEQ_VERSION, (int __user *)arg) ? -EFAULT : 0;
	case SNDRV_SEQ_IOCTL_CLIENT_ID:
		/* return the id of this client */
		return put_user(client->number, (int __user *)arg) ? -EFAULT : 0;
	}

	if (! arg)
		return -EFAULT;
	for (p = ioctl_tables; p->cmd; p++) {
		if (p->cmd == cmd)
			return p->func(client, arg);
	}
	snd_printd("seq unknown ioctl() 0x%x (type='%c', number=0x%2x)\n",
		   cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
	return -ENOTTY;
}


static int snd_seq_ioctl(struct inode *inode, struct file *file,
			 unsigned int cmd, unsigned long arg)
{
	client_t *client = (client_t *) file->private_data;
	int err;

	snd_assert(client != NULL, return -ENXIO);
		
	/* FIXME: need to unlock BKL to allow preemption */
	unlock_kernel();
	err = snd_seq_do_ioctl(client, cmd, (void __user *) arg);
	lock_kernel();
	return err;
}


/* -------------------------------------------------------- */


/* exported to kernel modules */
int snd_seq_create_kernel_client(snd_card_t *card, int client_index, snd_seq_client_callback_t * callback)
{
	client_t *client;

	snd_assert(! in_interrupt(), return -EBUSY);

	if (callback == NULL)
		return -EINVAL;
	if (card && client_index > 7)
		return -EINVAL;
	if (card == NULL && client_index > 63)
		return -EINVAL;
	if (card)
		client_index += 64 + (card->number << 3);

	if (down_interruptible(&register_mutex))
		return -ERESTARTSYS;
	/* empty write queue as default */
	client = seq_create_client1(client_index, 0);
	if (client == NULL) {
		up(&register_mutex);
		return -EBUSY;	/* failure code */
	}
	usage_alloc(&client_usage, 1);

	client->accept_input = callback->allow_output;
	client->accept_output = callback->allow_input;
		
	/* fill client data */
	client->data.kernel.card = card;
	client->data.kernel.private_data = callback->private_data;
	sprintf(client->name, "Client-%d", client->number);

	client->type = KERNEL_CLIENT;
	up(&register_mutex);

	/* make others aware this new client */
	snd_seq_system_client_ev_client_start(client->number);
	
	/* return client number to caller */
	return client->number;
}

/* exported to kernel modules */
int snd_seq_delete_kernel_client(int client)
{
	client_t *ptr;

	snd_assert(! in_interrupt(), return -EBUSY);

	ptr = clientptr(client);
	if (ptr == NULL)
		return -EINVAL;

	seq_free_client(ptr);
	kfree(ptr);
	return 0;
}


/* skeleton to enqueue event, called from snd_seq_kernel_client_enqueue
 * and snd_seq_kernel_client_enqueue_blocking
 */
static int kernel_client_enqueue(int client, snd_seq_event_t *ev,
				 struct file *file, int blocking,
				 int atomic, int hop)
{
	client_t *cptr;
	int result;

	snd_assert(ev != NULL, return -EINVAL);

	if (ev->type == SNDRV_SEQ_EVENT_NONE)
		return 0; /* ignore this */
	if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
		return -EINVAL; /* quoted events can't be enqueued */

	/* fill in client number */
	ev->source.client = client;

	if (check_event_type_and_length(ev))
		return -EINVAL;

	cptr = snd_seq_client_use_ptr(client);
	if (cptr == NULL)
		return -EINVAL;
	
	if (! cptr->accept_output)
		result = -EPERM;
	else /* send it */
		result = snd_seq_client_enqueue_event(cptr, ev, file, blocking, atomic, hop);

	snd_seq_client_unlock(cptr);
	return result;
}

/*
 * exported, called by kernel clients to enqueue events (w/o blocking)
 *
 * RETURN VALUE: zero if succeed, negative if error
 */
int snd_seq_kernel_client_enqueue(int client, snd_seq_event_t * ev,
				  int atomic, int hop)
{
	return kernel_client_enqueue(client, ev, NULL, 0, atomic, hop);
}

/*
 * exported, called by kernel clients to enqueue events (with blocking)
 *
 * RETURN VALUE: zero if succeed, negative if error
 */
int snd_seq_kernel_client_enqueue_blocking(int client, snd_seq_event_t * ev,
					   struct file *file,
					   int atomic, int hop)
{
	return kernel_client_enqueue(client, ev, file, 1, atomic, hop);
}


/* 
 * exported, called by kernel clients to dispatch events directly to other
 * clients, bypassing the queues.  Event time-stamp will be updated.
 *
 * RETURN VALUE: negative = delivery failed,
 *		 zero, or positive: the number of delivered events
 */
int snd_seq_kernel_client_dispatch(int client, snd_seq_event_t * ev,
				   int atomic, int hop)
{
	client_t *cptr;
	int result;

	snd_assert(ev != NULL, return -EINVAL);

	/* fill in client number */
	ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
	ev->source.client = client;

	if (check_event_type_and_length(ev))
		return -EINVAL;

	cptr = snd_seq_client_use_ptr(client);
	if (cptr == NULL)
		return -EINVAL;

	if (!cptr->accept_output)
		result = -EPERM;
	else
		result = snd_seq_deliver_event(cptr, ev, atomic, hop);

	snd_seq_client_unlock(cptr);
	return result;
}


/*
 * exported, called by kernel clients to perform same functions as with
 * userland ioctl() 
 */
int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
{
	client_t *client;
	mm_segment_t fs;
	int result;

	client = clientptr(clientid);
	if (client == NULL)
		return -ENXIO;
	fs = snd_enter_user();
	result = snd_seq_do_ioctl(client, cmd, arg);
	snd_leave_user(fs);
	return result;
}


/* exported (for OSS emulator) */
int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
{
	client_t *client;

	client = clientptr(clientid);
	if (client == NULL)
		return -ENXIO;

	if (! snd_seq_write_pool_allocated(client))
		return 1;
	if (snd_seq_pool_poll_wait(client->pool, file, wait))
		return 1;
	return 0;
}

/*---------------------------------------------------------------------------*/

/*
 *  /proc interface
 */
static void snd_seq_info_dump_subscribers(snd_info_buffer_t *buffer, port_subs_info_t *group, int is_src, char *msg)
{
	struct list_head *p;
	subscribers_t *s;
	int count = 0;

	down_read(&group->list_mutex);
	if (list_empty(&group->list_head)) {
		up_read(&group->list_mutex);
		return;
	}
	snd_iprintf(buffer, msg);
	list_for_each(p, &group->list_head) {
		if (is_src)
			s = list_entry(p, subscribers_t, src_list);
		else
			s = list_entry(p, subscribers_t, dest_list);
		if (count++)
			snd_iprintf(buffer, ", ");
		snd_iprintf(buffer, "%d:%d",
			    is_src ? s->info.dest.client : s->info.sender.client,
			    is_src ? s->info.dest.port : s->info.sender.port);
		if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
			snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
		if (group->exclusive)
			snd_iprintf(buffer, "[ex]");
	}
	up_read(&group->list_mutex);
	snd_iprintf(buffer, "\n");
}

#define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
#define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
#define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')

#define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')

static void snd_seq_info_dump_ports(snd_info_buffer_t *buffer, client_t *client)
{
	struct list_head *l;

	down(&client->ports_mutex);
	list_for_each(l, &client->ports_list_head) {
		client_port_t *p = list_entry(l, client_port_t, list);
		snd_iprintf(buffer, "  Port %3d : \"%s\" (%c%c%c%c)\n",
			    p->addr.port, p->name,
			    FLAG_PERM_RD(p->capability),
			    FLAG_PERM_WR(p->capability),
			    FLAG_PERM_EX(p->capability),
			    FLAG_PERM_DUPLEX(p->capability));
		snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, "    Connecting To: ");
		snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, "    Connected From: ");
	}
	up(&client->ports_mutex);
}


/* exported to seq_info.c */
void snd_seq_info_clients_read(snd_info_entry_t *entry, 
			       snd_info_buffer_t * buffer)
{
	extern void snd_seq_info_pool(snd_info_buffer_t * buffer, pool_t * pool, char *space);
	int c;
	client_t *client;

	snd_iprintf(buffer, "Client info\n");
	snd_iprintf(buffer, "  cur  clients : %d\n", client_usage.cur);
	snd_iprintf(buffer, "  peak clients : %d\n", client_usage.peak);
	snd_iprintf(buffer, "  max  clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
	snd_iprintf(buffer, "\n");

	/* list the client table */
	for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
		client = snd_seq_client_use_ptr(c);
		if (client == NULL)
			continue;
		if (client->type == NO_CLIENT) {
			snd_seq_client_unlock(client);
			continue;
		}

		snd_iprintf(buffer, "Client %3d : \"%s\" [%s]\n",
			    c, client->name,
			    client->type == USER_CLIENT ? "User" : "Kernel");
		snd_seq_info_dump_ports(buffer, client);
		if (snd_seq_write_pool_allocated(client)) {
			snd_iprintf(buffer, "  Output pool :\n");
			snd_seq_info_pool(buffer, client->pool, "    ");
		}
		if (client->type == USER_CLIENT && client->data.user.fifo &&
		    client->data.user.fifo->pool) {
			snd_iprintf(buffer, "  Input pool :\n");
			snd_seq_info_pool(buffer, client->data.user.fifo->pool, "    ");
		}
		snd_seq_client_unlock(client);
	}
}


/*---------------------------------------------------------------------------*/


/*
 *  REGISTRATION PART
 */

static struct file_operations snd_seq_f_ops =
{
	.owner =	THIS_MODULE,
	.read =		snd_seq_read,
	.write =	snd_seq_write,
	.open =		snd_seq_open,
	.release =	snd_seq_release,
	.poll =		snd_seq_poll,
	.ioctl =	snd_seq_ioctl,
};

static snd_minor_t snd_seq_reg =
{
	.comment =	"sequencer",
	.f_ops =	&snd_seq_f_ops,
};


/* 
 * register sequencer device 
 */
int __init snd_sequencer_device_init(void)
{
	int err;

	if (down_interruptible(&register_mutex))
		return -ERESTARTSYS;

	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0, &snd_seq_reg, "seq")) < 0) {
		up(&register_mutex);
		return err;
	}
	
	up(&register_mutex);

	return 0;
}



/* 
 * unregister sequencer device 
 */
void __exit snd_sequencer_device_done(void)
{
	snd_unregister_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0);
}