* to handle any preventable race conditions, so TIPC will do the same ...
*
* TIPC sets the returned events as follows:
- * a) POLLRDNORM and POLLIN are set if the socket's receive queue is non-empty
- * or if a connection-oriented socket is does not have an active connection
- * (i.e. a read operation will not block).
- * b) POLLOUT is set except when a socket's connection has been terminated
- * (i.e. a write operation will not block).
- * c) POLLHUP is set when a socket's connection has been terminated.
- *
- * IMPORTANT: The fact that a read or write operation will not block does NOT
- * imply that the operation will succeed!
+ *
+ * socket state flags set
+ * ------------ ---------
+ * unconnected no read flags
+ * no write flags
+ *
+ * connecting POLLIN/POLLRDNORM if ACK/NACK in rx queue
+ * no write flags
+ *
+ * connected POLLIN/POLLRDNORM if data in rx queue
+ * POLLOUT if port is not congested
+ *
+ * disconnecting POLLIN/POLLRDNORM/POLLHUP
+ * no write flags
+ *
+ * listening POLLIN if SYN in rx queue
+ * no write flags
+ *
+ * ready POLLIN/POLLRDNORM if data in rx queue
+ * [connectionless] POLLOUT (since port cannot be congested)
+ *
+ * IMPORTANT: The fact that a read or write operation is indicated does NOT
+ * imply that the operation will succeed, merely that it should be performed
+ * and will not block.
*/
static unsigned int poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
- u32 mask;
+ u32 mask = 0;
poll_wait(file, sk_sleep(sk), wait);
- if (!skb_queue_empty(&sk->sk_receive_queue) ||
- (sock->state == SS_UNCONNECTED) ||
- (sock->state == SS_DISCONNECTING))
- mask = (POLLRDNORM | POLLIN);
- else
- mask = 0;
-
- if (sock->state == SS_DISCONNECTING)
- mask |= POLLHUP;
- else
- mask |= POLLOUT;
+ switch ((int)sock->state) {
+ case SS_READY:
+ case SS_CONNECTED:
+ if (!tipc_sk_port(sk)->congested)
+ mask |= POLLOUT;
+ /* fall thru' */
+ case SS_CONNECTING:
+ case SS_LISTENING:
+ if (!skb_queue_empty(&sk->sk_receive_queue))
+ mask |= (POLLIN | POLLRDNORM);
+ break;
+ case SS_DISCONNECTING:
+ mask = (POLLIN | POLLRDNORM | POLLHUP);
+ break;
+ }
return mask;
}
struct sk_buff *buf;
struct tipc_msg *msg;
unsigned int sz;
- int sz_to_copy;
+ int sz_to_copy, target, needed;
int sz_copied = 0;
- int needed;
char __user *crs = m->msg_iov->iov_base;
unsigned char *buf_crs;
u32 err;
goto exit;
}
+ target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
+
restart:
/* Look for a message in receive queue; wait if necessary */
if ((sz_copied < buf_len) && /* didn't get all requested data */
(!skb_queue_empty(&sk->sk_receive_queue) ||
- (flags & MSG_WAITALL)) && /* and more is ready or required */
+ (sz_copied < target)) && /* and more is ready or required */
(!(flags & MSG_PEEK)) && /* and aren't just peeking at data */
(!err)) /* and haven't reached a FIN */
goto restart;
/* For now, TIPC does not support the non-blocking form of connect() */
if (flags & O_NONBLOCK) {
- res = -EWOULDBLOCK;
+ res = -EOPNOTSUPP;
goto exit;
}