Revive http keep alive to save tcp connection setup costs

1 files changed, 18 insertions, 8 deletions

diff --git a/ot_http.c b/ot_http.c
index 36819c7..14952b5 100644
--- a/ot_http.c
+++ b/ot_http.c
@@ -727,6 +727,24 @@ ssize_t http_handle_request(const int64_t sock, struct ot_workstruct *ws) {
   /* Tell subroutines where to put reply data */
   ws->reply = ws->outbuf + SUCCESS_HTTP_HEADER_LENGTH;
 
+  /* Find out if the client wants to keep this connection alive, before any
+     subroutine gets to answer: an error reply finishes with the connection
+     on its way out, and ws outlives the connection it was serving */
+  ws->keep_alive = 0;
+#ifdef WANT_KEEPALIVE
+  if ((write_ptr = http_header(ws->request, ws->header_size, "connection")) && (*write_ptr == 'K' || *write_ptr == 'k'))
+    ws->keep_alive = 1;
+#endif
+  {
+    struct http_data *connection = fdstate_cookie(sock);
+    if (connection) {
+      if (ws->keep_alive)
+        connection->flag |= STRUCT_HTTP_FLAG_KEEPALIVE;
+      else
+        connection->flag &= ~STRUCT_HTTP_FLAG_KEEPALIVE;
+    }
+  }
+
   /* This one implicitely tests strlen < 5, too -- remember, it is \n terminated */
   if (memcmp(read_ptr, "GET /", 5))
     HTTPERROR_400;
@@ -763,14 +781,6 @@ ssize_t http_handle_request(const int64_t sock, struct ot_workstruct *ws) {
   else
     HTTPERROR_404;
 
-  /* Find out if the client wants to keep this connection alive */
-  ws->keep_alive = 0;
-#ifdef WANT_KEEPALIVE
-  read_ptr = http_header(ws->request, ws->header_size, "connection");
-  if (read_ptr && (*read_ptr == 'K' || *read_ptr == 'k'))
-    ws->keep_alive = 1;
-#endif
-
   /* If routines handled sending themselves, just return */
   if (ws->reply_size == -2)
     return 0;