From 76e2cfc99a370f46d27f84a924472cef7e285ad4 Mon Sep 17 00:00:00 2001
From: Dmitri Tikhonov <dtikhonov@litespeedtech.com>
Date: Fri, 17 Apr 2020 12:07:22 -0400
Subject: [PATCH] Fix: a connection is tickable if it has unsent packets

---
 src/liblsquic/lsquic_full_conn.c      |  5 +++++
 src/liblsquic/lsquic_full_conn_ietf.c |  5 +++++
 src/liblsquic/lsquic_mini_conn.c      | 20 +++++++++++++++-----
 src/liblsquic/lsquic_mini_conn_ietf.c | 20 +++++++++++++++-----
 4 files changed, 40 insertions(+), 10 deletions(-)

diff --git a/src/liblsquic/lsquic_full_conn.c b/src/liblsquic/lsquic_full_conn.c
index 14e6a2f..43586d4 100644
--- a/src/liblsquic/lsquic_full_conn.c
+++ b/src/liblsquic/lsquic_full_conn.c
@@ -4193,6 +4193,11 @@ full_conn_ci_is_tickable (lsquic_conn_t *lconn)
             LSQ_DEBUG("tickable: flags: 0x%X", conn->fc_flags & send_flags);
             goto check_can_send;
         }
+        if (lsquic_send_ctl_n_scheduled(&conn->fc_send_ctl) > 0)
+        {
+            LSQ_DEBUG("tickable: has scheduled packets");
+            return 1;   /* Don't check can_send */
+        }
         if ((conn->fc_conn.cn_flags & LSCONN_HANDSHAKE_DONE)
                 && lsquic_send_ctl_has_buffered(&conn->fc_send_ctl))
         {
diff --git a/src/liblsquic/lsquic_full_conn_ietf.c b/src/liblsquic/lsquic_full_conn_ietf.c
index f53925b..0a964d1 100644
--- a/src/liblsquic/lsquic_full_conn_ietf.c
+++ b/src/liblsquic/lsquic_full_conn_ietf.c
@@ -3541,6 +3541,11 @@ ietf_full_conn_ci_is_tickable (struct lsquic_conn *lconn)
             LSQ_DEBUG("tickable: send flags: 0x%X", conn->ifc_send_flags);
             goto check_can_send;
         }
+        if (lsquic_send_ctl_n_scheduled(&conn->ifc_send_ctl) > 0)
+        {
+            LSQ_DEBUG("tickable: has scheduled packets");
+            return 1;   /* Don't check can_send */
+        }
         if (conn->ifc_conn.cn_flags & LSCONN_SEND_BLOCKED)
         {
             LSQ_DEBUG("tickable: send DATA_BLOCKED frame");
diff --git a/src/liblsquic/lsquic_mini_conn.c b/src/liblsquic/lsquic_mini_conn.c
index ea03751..bf0dbfd 100644
--- a/src/liblsquic/lsquic_mini_conn.c
+++ b/src/liblsquic/lsquic_mini_conn.c
@@ -2071,14 +2071,24 @@ mini_conn_ci_hsk_done (struct lsquic_conn *lconn, enum lsquic_hsk_status status)
 }
 
 
+/* A mini connection is only tickable if it has unsent packets.  This can
+ * occur when packet sending is delayed.
+ *
+ * Otherwise, a mini connection is not tickable:  Either there are incoming
+ * packets, in which case, the connection is going to be ticked, or there is
+ * an alarm pending, in which case it will be handled via the attq.
+ */
 static int
 mini_conn_ci_is_tickable (struct lsquic_conn *lconn)
 {
-    /* A mini connection is never tickable:  Either there are incoming
-     * packets, in which case, the connection is going to be ticked, or
-     * there is an alarm pending, in which case it will be handled via
-     * the attq.
-     */
+    struct mini_conn *const mc = (struct mini_conn *) lconn;
+    const struct lsquic_packet_out *packet_out;
+
+    if (mc->mc_enpub->enp_flags & ENPUB_CAN_SEND)
+        TAILQ_FOREACH(packet_out, &mc->mc_packets_out, po_next)
+            if (!(packet_out->po_flags & PO_SENT))
+                return 1;
+
     return 0;
 }
 
diff --git a/src/liblsquic/lsquic_mini_conn_ietf.c b/src/liblsquic/lsquic_mini_conn_ietf.c
index b27152f..98c5484 100644
--- a/src/liblsquic/lsquic_mini_conn_ietf.c
+++ b/src/liblsquic/lsquic_mini_conn_ietf.c
@@ -574,14 +574,24 @@ ietf_mini_conn_ci_tls_alert (struct lsquic_conn *lconn, uint8_t alert)
 }
 
 
+/* A mini connection is only tickable if it has unsent packets.  This can
+ * occur when packet sending is delayed.
+ *
+ * Otherwise, a mini connection is not tickable:  Either there are incoming
+ * packets, in which case, the connection is going to be ticked, or there is
+ * an alarm pending, in which case it will be handled via the attq.
+ */
 static int
 ietf_mini_conn_ci_is_tickable (struct lsquic_conn *lconn)
 {
-    /* A mini connection is never tickable:  Either there are incoming
-     * packets, in which case, the connection is going to be ticked, or
-     * there is an alarm pending, in which case it will be handled via
-     * the attq.
-     */
+    struct ietf_mini_conn *const conn = (struct ietf_mini_conn *) lconn;
+    const struct lsquic_packet_out *packet_out;
+
+    if (conn->imc_enpub->enp_flags & ENPUB_CAN_SEND)
+        TAILQ_FOREACH(packet_out, &conn->imc_packets_out, po_next)
+            if (!(packet_out->po_flags & PO_SENT))
+                return 1;
+
     return 0;
 }