MEDIUM: stream-int: always consider all CS errors on the send side

We still have an issue with asynchronous errors, which is that while
they don't truncate reads anymore, they might be missed during a
send() attempt. This can happen for example when processing a request
followed by undesired data for which the stream doesn't try to receive,
while the send side experiences an error (transfer aborted by the client).
In this case we definitely want all send() attempts to fail as soon as
the error was reported, even if it's only pending. This way we leave an
opportunity to the stream interface to try to receive the last data
pending in the buffer but it cannot send anymore and knows that there
is an error when trying to do so.

diff --git a/src/stream_interface.c b/src/stream_interface.c
index d8fd6bdcced21fcc75bd05f794722f2b5edb289a..05306cf5a704894175b3a97e09f634333f48b86c 100644 (file)
--- a/src/stream_interface.c
+++ b/src/stream_interface.c
@@ -615,8 +615,10 @@ int si_cs_send(struct conn_stream *cs)
        if (si->wait_event.events & SUB_RETRY_SEND)
                return 0;
 
-       if (conn->flags & CO_FL_ERROR || cs->flags & CS_FL_ERROR)
+       if (conn->flags & CO_FL_ERROR || cs->flags & (CS_FL_ERROR|CS_FL_ERR_PENDING)) {
+               si->flags |= SI_FL_ERR;
                return 1;
+       }
 
        /* we might have been called just after an asynchronous shutw */
        if (conn->flags & CO_FL_SOCK_WR_SH || oc->flags & CF_SHUTW)
@@ -634,8 +636,10 @@ int si_cs_send(struct conn_stream *cs)
                        oc->pipe = NULL;
                }
 
-               if (conn->flags & CO_FL_ERROR || cs->flags & CS_FL_ERROR)
+               if (conn->flags & CO_FL_ERROR || cs->flags & (CS_FL_ERROR|CS_FL_ERR_PENDING)) {
+                       si->flags |= SI_FL_ERR;
                        return 1;
+               }
 
                if (oc->pipe)
                        goto end;
@@ -689,8 +693,10 @@ int si_cs_send(struct conn_stream *cs)
                         */
                }
 
-               if (conn->flags & CO_FL_ERROR || cs->flags & CS_FL_ERROR)
+               if (conn->flags & CO_FL_ERROR || cs->flags & (CS_FL_ERROR|CS_FL_ERR_PENDING)) {
+                       si->flags |= SI_FL_ERR;
                        return 1;
+               }
        }
 
  end:
@@ -838,7 +844,7 @@ void si_update_both(struct stream_interface *si_f, struct stream_interface *si_b
            (si_b->state == SI_ST_EST || si_b->state == SI_ST_CON) &&
            !(req->flags & CF_SHUTW) && /* Write not closed */
            !channel_is_empty(req) &&
-           !(cs->flags & CS_FL_ERROR) &&
+           !(cs->flags & (CS_FL_ERROR|CS_FL_ERR_PENDING)) &&
            !(cs->conn->flags & CO_FL_ERROR)) {
                if (si_cs_send(cs))
                        si_rx_room_rdy(si_f);
@@ -1023,7 +1029,7 @@ static void stream_int_chk_snd_conn(struct stream_interface *si)
        if (!(si->wait_event.events & SUB_RETRY_SEND) && !channel_is_empty(si_oc(si)))
                si_cs_send(cs);
 
-       if (cs->flags & CS_FL_ERROR || cs->conn->flags & CO_FL_ERROR) {
+       if (cs->flags & (CS_FL_ERROR|CS_FL_ERR_PENDING) || cs->conn->flags & CO_FL_ERROR) {
                /* Write error on the file descriptor */
                si->flags |= SI_FL_ERR;
                goto out_wakeup;