QUIC: idle mode for main connection.

Now main QUIC connection for HTTP/3 always has c->idle flag set.  This allows
the connection to receive worker shutdown notification.  It is passed to
application level via a new conf->shutdown() callback.

The HTTP/3 shutdown callback sends GOAWAY to client and gracefully shuts down
the QUIC connection.

2 files changed, 19 insertions, 3 deletions

diff --git a/src/event/quic/ngx_event_quic.c b/src/event/quic/ngx_event_quic.c
index 7245ee7d0..a28f5a7ac 100644
--- a/src/event/quic/ngx_event_quic.c
+++ b/src/event/quic/ngx_event_quic.c
@@ -341,6 +341,7 @@ ngx_quic_new_connection(ngx_connection_t *c, ngx_quic_conf_t *conf,
         return NULL;
     }
 
+    c->idle = 1;
     ngx_reusable_connection(c, 1);
 
     ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0,
@@ -420,9 +421,19 @@ ngx_quic_input_handler(ngx_event_t *rev)
     }
 
     if (c->close) {
-        qc->error = NGX_QUIC_ERR_NO_ERROR;
-        qc->error_reason = "graceful shutdown";
-        ngx_quic_close_connection(c, NGX_ERROR);
+        c->close = 0;
+
+        if (!ngx_exiting) {
+            qc->error = NGX_QUIC_ERR_NO_ERROR;
+            qc->error_reason = "graceful shutdown";
+            ngx_quic_close_connection(c, NGX_ERROR);
+            return;
+        }
+
+        if (!qc->closing && qc->conf->shutdown) {
+            qc->conf->shutdown(c);
+        }
+
         return;
     }
 
diff --git a/src/event/quic/ngx_event_quic.h b/src/event/quic/ngx_event_quic.h
index d33bd8d4d..335d925cb 100644
--- a/src/event/quic/ngx_event_quic.h
+++ b/src/event/quic/ngx_event_quic.h
@@ -28,6 +28,9 @@
 #define NGX_QUIC_STREAM_UNIDIRECTIONAL       0x02
 
 
+typedef void (*ngx_quic_shutdown_pt)(ngx_connection_t *c);
+
+
 typedef enum {
     NGX_QUIC_STREAM_SEND_READY = 0,
     NGX_QUIC_STREAM_SEND_SEND,
@@ -74,6 +77,8 @@ typedef struct {
     ngx_int_t                      stream_reject_code_uni;
     ngx_int_t                      stream_reject_code_bidi;
 
+    ngx_quic_shutdown_pt           shutdown;
+
     u_char                         av_token_key[NGX_QUIC_AV_KEY_LEN];
     u_char                         sr_token_key[NGX_QUIC_SR_KEY_LEN];
 } ngx_quic_conf_t;