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.
diff --git a/src/core/ngx_connection.h b/src/core/ngx_connection.h
index 8cc1475..6d3348d 100644
--- a/src/core/ngx_connection.h
+++ b/src/core/ngx_connection.h
@@ -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;
diff --git a/src/event/ngx_event_connect.c b/src/event/ngx_event_connect.c
index adbbde6..668084a 100644
--- a/src/event/ngx_event_connect.c
+++ b/src/event/ngx_event_connect.c
@@ -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;
diff --git a/src/event/ngx_event_udp.c b/src/event/ngx_event_udp.c
index 640b377..1ac82c7 100644
--- a/src/event/ngx_event_udp.c
+++ b/src/event/ngx_event_udp.c
@@ -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;
diff --git a/src/http/ngx_http_write_filter_module.c b/src/http/ngx_http_write_filter_module.c
index 932f26d..89ab49e 100644
--- a/src/http/ngx_http_write_filter_module.c
+++ b/src/http/ngx_http_write_filter_module.c
@@ -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 */) {
diff --git a/src/http/v2/ngx_http_v2_filter_module.c b/src/http/v2/ngx_http_v2_filter_module.c
index 9ffb155..62b6a04 100644
--- a/src/http/v2/ngx_http_v2_filter_module.c
+++ b/src/http/v2/ngx_http_v2_filter_module.c
@@ -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;
}
diff --git a/src/stream/ngx_stream_write_filter_module.c b/src/stream/ngx_stream_write_filter_module.c
index 156a61c..07dc7b5 100644
--- a/src/stream/ngx_stream_write_filter_module.c
+++ b/src/stream/ngx_stream_write_filter_module.c
@@ -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 */) {
