From: Guo-Fu Tseng <coolda...@cooldavid.org>
Michael suggested something like:
===============================================================
struct list_head received = LIST_HEAD_INIT ( received );
...
while ( ! list_empty ( &tcp->rx_queue ) ) {
...
tcp_rx_data ( tcp, seq, iob_disown ( iobuf ), &received );
...
}
list_for_each_entry_safe ( iobuf, tmp, &received, list ) {
// deliver iobuf via xfer_deliver_iob()
}
if ( tcp->state & TCP_STATE_RCVD ( TCP_FIN ) )
tcp_close ( tcp, 0 );
===============================================================
But after some thought I think making the change like this commit
can have same behavior, but simplified by not using extra queue.
Which can also save some code size.
In this patch:
1. We call xfer_deliver_iob() after fully updated/handled received TCP
state. In which to have better timing that upper-layer protocol
might call tcp_xfer_close() to initiate a shutdown, or sending
extra data.
2. We move tcp_close() out from tcp_rx_fin() because tcp_close()
nullified the xfer interface. It'll cause error to call
xfer_deliver_iob() after tcp_rx_fin().
(So that I proposed an idea to clean up tcp_close(), I'll post it
in later commit.)
Signed-off-by: Guo-Fu Tseng <coolda...@cooldavid.org>
---
src/net/tcp.c | 34 +++++++++++++++++++---------------
1 files changed, 19 insertions(+), 15 deletions(-)
diff --git a/src/net/tcp.c b/src/net/tcp.c
index 637bfce..b30c91c 100644
--- a/src/net/tcp.c
+++ b/src/net/tcp.c
@@ -861,18 +861,17 @@ static int tcp_rx_ack ( struct tcp_connection *tcp,
uint32_t ack,
*
* This function takes ownership of the I/O buffer.
*/
-static int tcp_rx_data ( struct tcp_connection *tcp, uint32_t seq,
+static struct io_buffer* tcp_rx_data ( struct tcp_connection *tcp, uint32_t
seq,
struct io_buffer *iobuf ) {
uint32_t already_rcvd;
uint32_t len;
- int rc;
/* Ignore duplicate or out-of-order data */
already_rcvd = ( tcp->rcv_ack - seq );
len = iob_len ( iobuf );
if ( already_rcvd >= len ) {
free_iob ( iobuf );
- return 0;
+ return NULL;
}
iob_pull ( iobuf, already_rcvd );
len -= already_rcvd;
@@ -880,14 +879,7 @@ static int tcp_rx_data ( struct tcp_connection *tcp,
uint32_t seq,
/* Acknowledge new data */
tcp_rx_seq ( tcp, len );
- /* Deliver data to application */
- if ( ( rc = xfer_deliver_iob ( &tcp->xfer, iobuf ) ) != 0 ) {
- DBGC ( tcp, "TCP %p could not deliver %08x..%08x: %s\n",
- tcp, seq, ( seq + len ), strerror ( rc ) );
- return rc;
- }
-
- return 0;
+ return iobuf;
}
/**
@@ -909,9 +901,6 @@ static int tcp_rx_fin ( struct tcp_connection *tcp,
uint32_t seq ) {
/* Mark FIN as received */
tcp->tcp_state |= TCP_STATE_RCVD ( TCP_FIN );
- /* Close connection */
- tcp_close ( tcp, 0 );
-
return 0;
}
@@ -1009,6 +998,7 @@ static void tcp_process_rx_queue ( struct tcp_connection
*tcp ) {
uint32_t seq;
unsigned int flags;
size_t len;
+ int rc;
/* Process all applicable received buffers */
list_for_each_entry_safe ( iobuf, tmp, &tcp->rx_queue, list ) {
@@ -1024,7 +1014,7 @@ static void tcp_process_rx_queue ( struct tcp_connection
*tcp ) {
len = iob_len ( iobuf );
/* Handle new data, if any */
- tcp_rx_data ( tcp, seq, iob_disown ( iobuf ) );
+ iobuf = tcp_rx_data ( tcp, seq, iobuf );
seq += len;
/* Handle FIN, if present */
@@ -1032,6 +1022,20 @@ static void tcp_process_rx_queue ( struct tcp_connection
*tcp ) {
tcp_rx_fin ( tcp, seq );
seq++;
}
+
+ /* Deliver data to application, if any */
+ if ( iobuf &&
+ ( rc = xfer_deliver_iob ( &tcp->xfer,
+ iob_disown ( iobuf ) ) ) != 0 ) {
+ DBGC ( tcp, "TCP %p could not deliver %08x..%08x: %s\n",
+ tcp, ( seq - len - ( flags & TCP_FIN ) ? 1 : 0 ),
+ seq, strerror ( rc ) );
+ }
+ }
+
+ if ( tcp->tcp_state & TCP_STATE_RCVD ( TCP_FIN ) ) {
+ /* Close connection */
+ tcp_close ( tcp, 0 );
}
}
--
1.7.1
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