[PATCH 02 of 25] Fix for incorrect 201 replies from dav module

[Maxim Dounin]

# HG changeset patch
# User Maxim Dounin <mdounin at mdounin.ru>
# Date 1315324342 -14400
# Node ID d90e06868b1d53b1da9280c81c113255a3982c92
# Parent  08a723d1784ec0734114f669626189f3de69ae2d
Fix for incorrect 201 replies from dav module.

Replies with 201 code contain body, and we should clearly indicate it's
empty if it's empty.  Before 0.8.32 chunked was explicitly disabled for
201 replies and as a result empty body was indicated by connection close
(not perfect, but worked).  Since 0.8.32 chunked is enabled, and this
causes incorrect responses from dav module when HTTP/1.1 is used: with
"Transfer-Encoding: chunked" but no chunks at all.

Fix is to actually return empty body in special response handler instead
of abusing r->header_only flag.

See here for initial report:
http://nginx.org/pipermail/nginx-ru/2010-October/037535.html

diff --git a/src/http/ngx_http_special_response.c b/src/http/ngx_http_special_response.c
--- a/src/http/ngx_http_special_response.c
+++ b/src/http/ngx_http_special_response.c
@@ -421,7 +421,6 @@ ngx_http_special_response_handler(ngx_ht
     if (error == NGX_HTTP_CREATED) {
         /* 201 */
         err = 0;
-        r->header_only = 1;
 
     } else if (error == NGX_HTTP_NO_CONTENT) {
         /* 204 */
@@ -636,7 +635,7 @@ ngx_http_send_special_response(ngx_http_
         r->headers_out.content_type_lowcase = NULL;
 
     } else {
-        r->headers_out.content_length_n = -1;
+        r->headers_out.content_length_n = 0;
     }
 
     if (r->headers_out.content_length) {
@@ -654,7 +653,7 @@ ngx_http_send_special_response(ngx_http_
     }
 
     if (ngx_http_error_pages[err].len == 0) {
-        return NGX_OK;
+        return ngx_http_send_special(r, NGX_HTTP_LAST);
     }
 
     b = ngx_calloc_buf(r->pool);