Release 2.6.4

- [BUGFIX] High priority buffered packet queue length.
- [BUGFIX] Rain time calculation: max_ack_delay is in milliseconds.

include/lsquic.h

@@ -25,7 +25,7 @@ extern "C" {
 
 #define LSQUIC_MAJOR_VERSION 2
 #define LSQUIC_MINOR_VERSION 6
-#define LSQUIC_PATCH_VERSION 3
+#define LSQUIC_PATCH_VERSION 4
 
 /**
  * Engine flags:
@@ -323,8 +323,6 @@ typedef struct ssl_ctx_st * (*lsquic_lookup_cert_f)(
 
 #define LSQUIC_DF_STTL               86400
 #define LSQUIC_DF_MAX_INCHOATE     (1 * 1000 * 1000)
-#define LSQUIC_DF_SUPPORT_SREJ_SERVER  1
-#define LSQUIC_DF_SUPPORT_SREJ_CLIENT  0       /* TODO: client support */
 /** Do not use NSTP by default */
 #define LSQUIC_DF_SUPPORT_NSTP     0
 /** TODO: IETF QUIC clients do not support push */
@@ -467,13 +465,6 @@ struct lsquic_engine_settings {
      */
     unsigned        es_max_inchoate;
 
-    /**
-     * Support SREJ: for client side, this means supporting server's SREJ
-     * responses (this does not work yet) and for server side, this means
-     * generating SREJ instead of REJ when appropriate.
-     */
-    int             es_support_srej;
-
     /**
      * Setting this value to 0 means that
      *