diff options
Diffstat (limited to 'nuttx/net/recvfrom.c')
| -rw-r--r-- | nuttx/net/recvfrom.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/nuttx/net/recvfrom.c b/nuttx/net/recvfrom.c index 51027e0f8..78990fd39 100644 --- a/nuttx/net/recvfrom.c +++ b/nuttx/net/recvfrom.c @@ -1079,7 +1079,25 @@ static ssize_t tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len, else #endif + + /* We get here when we we decide that we need to setup the wait for incoming + * TCP/IP data. Just a few more conditions to check: + * + * 1) Make sure thet there is buffer space to receive additional data + * (state.rf_buflen > 0). This could be zero, for example, if read-ahead + * buffering was enabled and we filled the user buffer with data from + * the read-ahead buffers. Aand + * 2) if read-ahead buffering is enabled (CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0) + * and delay logic is disabled (CONFIG_NET_TCP_RECVDELAY == 0), then we + * not want to wait if we already obtained some data from the read-ahead + * buffer. In that case, return now with what we have. + */ + +#if CONFIG_NET_TCP_RECVDELAY == 0 && CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0 + if (state.rf_recvlen == 0 && state.rf_buflen > 0) +#else if (state.rf_buflen > 0) +#endif { struct uip_conn *conn = (struct uip_conn *)psock->s_conn; |