From: Maxim Dounin <mdounin@mdounin.ru>
Date: Mon, 26 Jun 2017 21:53:46 +0000 (+0300)
Subject: Range filter: allowed ranges on empty files (ticket #1031).
X-Git-Tag: release-1.13.2~1
X-Git-Url: http://www.kaiwu.me/postgresql/commit/?a=commitdiff_plain;h=774f179a9b523cff2233846283dc35a5582aa1d1;p=nginx.git

Range filter: allowed ranges on empty files (ticket #1031).

As per RFC 2616 / RFC 7233, any range request to an empty file
is expected to result in 416 Range Not Satisfiable response, as
there cannot be a "byte-range-spec whose first-byte-pos is less
than the current length of the entity-body".  On the other hand,
this makes use of byte-range requests inconvenient in some cases,
as reported for the slice module here:

http://mailman.nginx.org/pipermail/nginx-devel/2017-June/010177.html

This commit changes range filter to instead return 200 if the file
is empty and the range requested starts at 0.
---

diff --git a/src/http/modules/ngx_http_range_filter_module.c b/src/http/modules/ngx_http_range_filter_module.c
index 8ffca82e6..7ad9db9dd 100644
--- a/src/http/modules/ngx_http_range_filter_module.c
+++ b/src/http/modules/ngx_http_range_filter_module.c
@@ -382,6 +382,9 @@ ngx_http_range_parse(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx,
             if (ranges-- == 0) {
                 return NGX_DECLINED;
             }
+
+        } else if (start == 0) {
+            return NGX_DECLINED;
         }
 
         if (*p++ != ',') {