[PATCH] Proxy: set u->keepalive also if the whole body has already been read.

[Jan Prachař]

# HG changeset patch
# User Jan Prachař <jan.prachar at gmail.com>
# Date 1600710589 -7200
#      Mon Sep 21 19:49:49 2020 +0200
# Node ID f211684e1acee34eabfdd9dd39283bcff8dc7087
# Parent  052ecc68d35038b1b4adde12efe6249a92055f09
Proxy: set u->keepalive also if the whole body has already been read.

HTTP redirection responses often contain a small few hundred bytes
body. This
allows to left keep alive connection open, if the body fits into the
upstream
buffer.

diff -r 052ecc68d350 -r f211684e1ace
src/http/modules/ngx_http_proxy_module.c
--- a/src/http/modules/ngx_http_proxy_module.c	Wed Sep 16 18:26:25
2020 +0300
+++ b/src/http/modules/ngx_http_proxy_module.c	Mon Sep 21 19:49:49
2020 +0200
@@ -1905,7 +1905,8 @@
             }
 
             /*
-             * set u->keepalive if response has no body; this allows
to keep
+             * set u->keepalive if response has no body or if the
whole body
+             * has been already read to u->buffer; this allows to keep
              * connections alive in case of r->header_only or X-Accel-
Redirect
              */
 
@@ -1915,7 +1916,7 @@
                 || u->headers_in.status_n == NGX_HTTP_NOT_MODIFIED
                 || ctx->head
                 || (!u->headers_in.chunked
-                    && u->headers_in.content_length_n == 0))
+                    && u->headers_in.content_length_n <= u-
>buffer.last-u->buffer.pos))
             {
                 u->keepalive = !u->headers_in.connection_close;
             }