changeset 8006:32b0ba4855a6

HTTP/2: made it possible to flush response headers (ticket #1743). Response headers can be buffered in the SSL buffer. But stream's fake connection buffered flag did not reflect this, so any attempts to flush the buffer without sending additional data were stopped by the write filter. It does not seem to be possible to reflect this in fc->buffered though, as we never known if main connection's c->buffered corresponds to the particular stream or not. As such, fc->buffered might prevent request finalization due to sending data on some other stream. Fix is to implement handling of flush buffers when the c->need_flush_buf flag is set, similarly to the existing last buffer handling. The same flag is now used for UDP sockets in the stream module instead of explicit checking of c->type.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 03 Feb 2022 01:44:38 +0300
parents dd718d1cef3c
children 011f5ebdb928
files src/core/ngx_connection.h src/event/ngx_event_connect.c src/event/ngx_event_udp.c src/http/ngx_http_write_filter_module.c src/http/v2/ngx_http_v2_filter_module.c src/stream/ngx_stream_write_filter_module.c
diffstat 6 files changed, 14 insertions(+), 3 deletions(-) [+]
line wrap: on
line diff
--- a/src/core/ngx_connection.h	Tue Feb 01 16:29:28 2022 +0300
+++ b/src/core/ngx_connection.h	Thu Feb 03 01:44:38 2022 +0300
@@ -184,6 +184,7 @@
     unsigned            tcp_nopush:2;    /* ngx_connection_tcp_nopush_e */
 
     unsigned            need_last_buf:1;
+    unsigned            need_flush_buf:1;
 
 #if (NGX_HAVE_SENDFILE_NODISKIO || NGX_COMPAT)
     unsigned            busy_count:2;
--- a/src/event/ngx_event_connect.c	Tue Feb 01 16:29:28 2022 +0300
+++ b/src/event/ngx_event_connect.c	Thu Feb 03 01:44:38 2022 +0300
@@ -179,6 +179,8 @@
         c->recv = ngx_udp_recv;
         c->send = ngx_send;
         c->send_chain = ngx_udp_send_chain;
+
+        c->need_flush_buf = 1;
     }
 
     c->log_error = pc->log_error;
--- a/src/event/ngx_event_udp.c	Tue Feb 01 16:29:28 2022 +0300
+++ b/src/event/ngx_event_udp.c	Thu Feb 03 01:44:38 2022 +0300
@@ -246,6 +246,8 @@
         c->send = ngx_udp_send;
         c->send_chain = ngx_udp_send_chain;
 
+        c->need_flush_buf = 1;
+
         c->log = log;
         c->pool->log = log;
         c->listening = ls;
--- a/src/http/ngx_http_write_filter_module.c	Tue Feb 01 16:29:28 2022 +0300
+++ b/src/http/ngx_http_write_filter_module.c	Thu Feb 03 01:44:38 2022 +0300
@@ -227,7 +227,8 @@
 
     if (size == 0
         && !(c->buffered & NGX_LOWLEVEL_BUFFERED)
-        && !(last && c->need_last_buf))
+        && !(last && c->need_last_buf)
+        && !(flush && c->need_flush_buf))
     {
         if (last || flush || sync) {
             for (cl = r->out; cl; /* void */) {
--- a/src/http/v2/ngx_http_v2_filter_module.c	Tue Feb 01 16:29:28 2022 +0300
+++ b/src/http/v2/ngx_http_v2_filter_module.c	Thu Feb 03 01:44:38 2022 +0300
@@ -665,6 +665,7 @@
 
     fc->send_chain = ngx_http_v2_send_chain;
     fc->need_last_buf = 1;
+    fc->need_flush_buf = 1;
 
     return ngx_http_v2_filter_send(fc, stream);
 }
@@ -1815,7 +1816,11 @@
 static ngx_inline ngx_int_t
 ngx_http_v2_filter_send(ngx_connection_t *fc, ngx_http_v2_stream_t *stream)
 {
-    if (stream->queued == 0) {
+    ngx_connection_t  *c;
+
+    c = stream->connection->connection;
+
+    if (stream->queued == 0 && !c->buffered) {
         fc->buffered &= ~NGX_HTTP_V2_BUFFERED;
         return NGX_OK;
     }
--- a/src/stream/ngx_stream_write_filter_module.c	Tue Feb 01 16:29:28 2022 +0300
+++ b/src/stream/ngx_stream_write_filter_module.c	Thu Feb 03 01:44:38 2022 +0300
@@ -235,7 +235,7 @@
     if (size == 0
         && !(c->buffered & NGX_LOWLEVEL_BUFFERED)
         && !(last && c->need_last_buf)
-        && !(c->type == SOCK_DGRAM && flush))
+        && !(flush && c->need_flush_buf))
     {
         if (last || flush || sync) {
             for (cl = *out; cl; /* void */) {