daemon/session: add write_queue_size

This data is useful to track whether our code has buffered any data
for writing to the socket. Tracking this in session instead of
tls_common_ctx is required to support other protocols, e.g. plain HTTP.

diff --git a/daemon/session.c b/daemon/session.c
index dc60cc8a154e44f789ec2ae7aed76bbc104e52dd..d5cb50021e4645a2552d1f2e82dff260334b7439 100644 (file)
--- a/daemon/session.c
+++ b/daemon/session.c
@@ -41,6 +41,7 @@ struct session {
        ssize_t wire_buf_end_idx;     /**< Data end offset in wire_buf. */
        uint64_t last_activity;       /**< Time of last IO activity (if any occurs).
                                       *   Otherwise session creation time. */
+       size_t write_queue_size;      /**< number of buffered write requests (by our code) */
 };
 
 static void on_session_close(uv_handle_t *handle)
@@ -521,7 +522,7 @@ knot_pkt_t *session_produce_packet(struct session *session, knot_mm_t *mm)
                session->wire_buf_end_idx = 0;
                return NULL;
        }
-       
+
        if (session->wire_buf_start_idx > session->wire_buf_end_idx) {
                session->sflags.wirebuf_error = true;
                session->wire_buf_start_idx = 0;
@@ -533,7 +534,7 @@ knot_pkt_t *session_produce_packet(struct session *session, knot_mm_t *mm)
        uint8_t *msg_start = &session->wire_buf[session->wire_buf_start_idx];
        ssize_t wirebuf_msg_data_size = session->wire_buf_end_idx - session->wire_buf_start_idx;
        uint16_t msg_size = 0;
-       
+
        if (!handle) {
                session->sflags.wirebuf_error = true;
                return NULL;
@@ -636,7 +637,7 @@ int session_discard_packet(struct session *session, const knot_pkt_t *pkt)
                session->wire_buf_start_idx += pkt_msg_size;
        }
        session->sflags.wirebuf_error = false;
-       
+
        wirebuf_data_size = session->wire_buf_end_idx - session->wire_buf_start_idx;
        if (wirebuf_data_size == 0) {
                session_wirebuf_discard(session);
@@ -760,3 +761,26 @@ uint64_t session_last_activity(struct session *s)
 {
        return s->last_activity;
 }
+
+bool session_write_queue_is_empty(struct session *session)
+{
+       return session->write_queue_size == 0;
+}
+
+int session_write_queue_inc(struct session *session)
+{
+       if (session->write_queue_size == SIZE_MAX) {
+               return kr_error(ERANGE);
+       }
+       session->write_queue_size += 1;
+       return kr_ok();
+}
+
+int session_write_queue_dec(struct session *session)
+{
+       if (session->write_queue_size == 0) {
+               return kr_error(ERANGE);
+       }
+       session->write_queue_size -= 1;
+       return kr_ok();
+}

diff --git a/daemon/session.h b/daemon/session.h
index 8750335d23dd2c8248dfd11766e7d159e0461c9f..15504ee00c41f95344841056e592a4dad2a893f1 100644 (file)
--- a/daemon/session.h
+++ b/daemon/session.h
@@ -137,3 +137,10 @@ void session_touch(struct session *s);
 /** Returns either creation time or time of last IO activity if any occurs. */
 /* Used for TCP timeout calculation. */
 uint64_t session_last_activity(struct session *s);
+
+/** Check whether the write queue is empty. */
+bool session_write_queue_is_empty(struct session *session);
+/** Increment the write queue size. */
+int session_write_queue_inc(struct session *session);
+/** Decrement the write queue size. */
+int session_write_queue_dec(struct session *session);