# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1404492436 -14400
# Node ID 35990c69b3ac3973ddb7844985b0a43fcdc17994
# Parent  9d3a9c45fc434a059c1429c20d27933df36bb7fc
Upstream: p->downstream_error instead of closing connection.

Previously, nginx closed client connection in cases when a response body
from upstream was needed to be cached or stored but shouldn't be sent to
the client.  While this is normal for HTTP, it is unacceptable for SPDY.

Fix is to use instead the p->downstream_error flag to prevent nginx from
sending anything downstream.  To make this work, the event pipe code was
modified to properly cache empty responses with the flag set.

diff --git a/src/event/ngx_event_pipe.c b/src/event/ngx_event_pipe.c
--- a/src/event/ngx_event_pipe.c
+++ b/src/event/ngx_event_pipe.c
@@ -439,7 +439,11 @@ ngx_event_pipe_read_upstream(ngx_event_p
         }
     }
 
-    if (p->cacheable && p->in) {
+    if (p->cacheable && (p->in || p->buf_to_file)) {
+
+        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, p->log, 0,
+                       "pipe write chain");
+
         if (ngx_event_pipe_write_chain_to_temp_file(p) == NGX_ABORT) {
             return NGX_ABORT;
         }
@@ -515,15 +519,6 @@ ngx_event_pipe_write_to_downstream(ngx_e
                 p->in = NULL;
             }
 
-            if (p->cacheable && p->buf_to_file) {
-                ngx_log_debug0(NGX_LOG_DEBUG_EVENT, p->log, 0,
-                               "pipe write chain");
-
-                if (ngx_event_pipe_write_chain_to_temp_file(p) == NGX_ABORT) {
-                    return NGX_ABORT;
-                }
-            }
-
             ngx_log_debug0(NGX_LOG_DEBUG_EVENT, p->log, 0,
                            "pipe write downstream done");
 
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -2357,21 +2357,17 @@ ngx_http_upstream_send_response(ngx_http
 
     if (r->header_only) {
 
-        if (u->cacheable || u->store) {
-
-            if (ngx_shutdown_socket(c->fd, NGX_WRITE_SHUTDOWN) == -1) {
-                ngx_connection_error(c, ngx_socket_errno,
-                                     ngx_shutdown_socket_n " failed");
-            }
-
-            r->read_event_handler = ngx_http_request_empty_handler;
-            r->write_event_handler = ngx_http_request_empty_handler;
-            c->error = 1;
-
-        } else {
+        if (!u->buffering) {
             ngx_http_upstream_finalize_request(r, u, rc);
             return;
         }
+
+        if (!u->cacheable && !u->store) {
+            ngx_http_upstream_finalize_request(r, u, rc);
+            return;
+        }
+
+        u->pipe->downstream_error = 1;
     }
 
     if (r->request_body && r->request_body->temp_file) {