nghttpd: Add --early-response option

This option is testing the client behavior when it gets response
before sending all request.

src/HttpServer.cc

@@ -113,7 +113,8 @@ Config::Config()
     daemon(false),
     verify_client(false),
     no_tls(false),
-    error_gzip(false)
+    error_gzip(false),
+    early_response(false)
 {}
 
 Stream::Stream(Http2Handler *handler, int32_t stream_id)
@@ -961,16 +962,21 @@ ssize_t file_read_callback
   while((nread = read(fd, buf, length)) == -1 && errno == EINTR);
 
   if(nread == -1) {
-    if(stream) {
-      remove_stream_read_timeout(stream);
-      remove_stream_write_timeout(stream);
-    }
+    remove_stream_read_timeout(stream);
+    remove_stream_write_timeout(stream);
 
     return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
   }
 
   if(nread == 0) {
     *data_flags |= NGHTTP2_DATA_FLAG_EOF;
+
+    if(nghttp2_session_get_stream_remote_close(session, stream_id) == 0) {
+      remove_stream_read_timeout(stream);
+      remove_stream_write_timeout(stream);
+
+      hd->submit_rst_stream(stream, NGHTTP2_NO_ERROR);
+    }
   }
 
   return nread;
@@ -1215,8 +1221,9 @@ int hd_on_frame_recv_callback
 
     if(frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
       remove_stream_read_timeout(stream);
-
-      prepare_response(stream, hd);
+      if(!hd->get_config()->early_response) {
+        prepare_response(stream, hd);
+      }
     } else {
       add_stream_read_timeout(stream);
     }
@@ -1250,12 +1257,17 @@ int hd_on_frame_recv_callback
         hd->submit_rst_stream(stream, NGHTTP2_PROTOCOL_ERROR);
         return 0;
       }
+
+      if(hd->get_config()->early_response) {
+        prepare_response(stream, hd);
+      }
     }
 
     if(frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
       remove_stream_read_timeout(stream);
-
-      prepare_response(stream, hd);
+      if(!hd->get_config()->early_response) {
+        prepare_response(stream, hd);
+      }
     } else {
       add_stream_read_timeout(stream);
     }

src/HttpServer.h

@@ -76,6 +76,7 @@ struct Config {
   bool verify_client;
   bool no_tls;
   bool error_gzip;
+  bool early_response;
   Config();
 };
 

src/nghttpd.cc

@@ -137,6 +137,9 @@ Options:
                      Path to  file that contains DH  parameters in PEM
                      format.  Without  this option, DHE  cipher suites
                      are not available.
+  --early-response   Start  sending response  when request  HEADERS is
+                     received,   rather  than   complete  request   is
+                     received.
   --version          Display version information and exit.
   -h, --help         Display this help and exit.)"
       << std::endl;
@@ -164,6 +167,7 @@ int main(int argc, char **argv)
       {"color", no_argument, &flag, 2},
       {"version", no_argument, &flag, 3},
       {"dh-param-file", required_argument, &flag, 4},
+      {"early-response", no_argument, &flag, 5},
       {nullptr, 0, nullptr, 0}
     };
     int option_index = 0;
@@ -242,6 +246,10 @@ int main(int argc, char **argv)
         // dh-param-file
         config.dh_param_file = optarg;
         break;
+      case 5:
+        // early-response
+        config.early_response = true;
+        break;
       }
       break;
     default: