[PATCH] req_res: do not send 502 on catchall error if response buffered

[Eric Wong <e@80x24.org>]

If we already started writing a response, we cannot be sending a
502 to inform a user a connection has failed.  This should
prevent errors from the OpenSSL layer about mismatched buffers
due to the combination of slow clients and upstreams prematurely
aborting.
---
 lib/yahns/req_res.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/yahns/req_res.rb b/lib/yahns/req_res.rb
index 041b908..4ad8e5c 100644
--- a/lib/yahns/req_res.rb
+++ b/lib/yahns/req_res.rb
@@ -76,7 +76,7 @@ def yahns_step # yahns event loop entry point
     when Errno::ECONNREFUSED, Errno::ECONNRESET, Errno::EPIPE
       e.set_backtrace([])
     end
-    c.proxy_err_response(502, self, e)
+    c.proxy_err_response(Yahns::WbufCommon === @resbuf ? nil : 502, self, e)
   end
 
   def send_req_body_chunk(buf)
-- 
EW