Release 2.16.1

- [FEATURE] Use "no-progress timeout" after which connection is closed.
- [BUGFIX] Select new SCID when current SCID is retired.
- [BUGFIX] Don't warn about dropped Initial packet sequence gaps during
  mini/full handoff.
- [BUGFIX] Send correct conn error when HTTP/3 frame is truncated.
- [BUGFIX] Mini conn: consider amplification when deciding to return
  TICK_SEND.
- [BUGFIX] Don't double-count tag length in amplification logic.
- [BUGFIX] Don't squeeze out lone path challenges.
- [BUGFIX] Log messages dealing with scheduled packet queue squeezing.
- [BUGFIX] don't wipe current path if no path challenge responses
  come back.
- [BUGFIX] When path is reset, don't lose path_id which is used for
  logging.
- Downgrade flow control violations to info log level from warnings.
- Fix connection cap extra check, avoid checks in nested calls.
- Fix some unit tests when extra checks are enabled.
- Use ls-hpack 2.2.1.
- Turn off unconditional extra checks for IETF clients.
- Extra checks: don't verify sent size of hello packets.  Client
  changes DCID length and this check will fail.

include/lsquic.h

@@ -25,7 +25,7 @@ extern "C" {
 
 #define LSQUIC_MAJOR_VERSION 2
 #define LSQUIC_MINOR_VERSION 16
-#define LSQUIC_PATCH_VERSION 0
+#define LSQUIC_PATCH_VERSION 1
 
 /**
  * Engine flags:
@@ -343,6 +343,12 @@ typedef struct ssl_ctx_st * (*lsquic_lookup_cert_f)(
 /** By default, incoming packet size is not limited. */
 #define LSQUIC_DF_MAX_UDP_PAYLOAD_SIZE_RX 0
 
+/** By default, drop no-progress connections after 60 seconds on the server */
+#define LSQUIC_DF_NOPROGRESS_TIMEOUT_SERVER 60
+
+/** By default, do not use no-progress timeout on the client */
+#define LSQUIC_DF_NOPROGRESS_TIMEOUT_CLIENT 0
+
 struct lsquic_engine_settings {
     /**
      * This is a bit mask wherein each bit corresponds to a value in
@@ -752,6 +758,20 @@ struct lsquic_engine_settings {
      * Default value is @ref LSQUIC_DF_MAX_UDP_PAYLOAD_SIZE_RX
      */
     unsigned short  es_max_udp_payload_size_rx;
+
+    /**
+     * No progress timeout.
+     *
+     * If connection does not make progress for this number of seconds, the
+     * connection is dropped.  Here, progress is defined as user streams
+     * being written to or read from.
+     *
+     * If this value is zero, this timeout is disabled.
+     *
+     * Default value is @ref LSQUIC_DF_NOPROGRESS_TIMEOUT_SERVER in server
+     * mode and @ref LSQUIC_DF_NOPROGRESS_TIMEOUT_CLIENT in client mode.
+     */
+    unsigned        es_noprogress_timeout;
 };
 
 /* Initialize `settings' to default values */