h2load: Fix bug that it did not try to connect to server again

src/h2load.cc

@@ -202,7 +202,9 @@ void readcb(struct ev_loop *loop, ev_io *w, int revents) {
   auto client = static_cast<Client *>(w->data);
   client->restart_timeout();
   if (client->do_read() != 0) {
-    client->fail();
+    if (client->try_again_or_fail() == 0) {
+      return;
+    }
     delete client;
     return;
   }
@@ -453,7 +455,7 @@ void Client::restart_timeout() {
   }
 }
 
-void Client::fail() {
+int Client::try_again_or_fail() {
   disconnect();
 
   if (new_connection_requested) {
@@ -471,13 +473,21 @@ void Client::fail() {
 
       // Keep using current address
       if (connect() == 0) {
-        return;
+        return 0;
       }
       std::cerr << "client could not connect to host" << std::endl;
     }
   }
 
   process_abandoned_streams();
+
+  return -1;
+}
+
+void Client::fail() {
+  disconnect();
+
+  process_abandoned_streams();
 }
 
 void Client::disconnect() {

src/h2load.h

@@ -307,6 +307,12 @@ struct Client {
   int connect();
   void disconnect();
   void fail();
+  // Call this function when do_read() returns -1.  This function
+  // tries to connect to the remote host again if it is requested.  If
+  // so, this function returns 0, and this object should be retained.
+  // Otherwise, this function returns -1, and this object should be
+  // deleted.
+  int try_again_or_fail();
   void timeout();
   void restart_timeout();
   int submit_request();