Fix fall-back on -ncp mode

When the requested engine could not be started, the user still had to
wait for the feature timeout to expire before the UI was re-enabled,
and the now-useless loading action would continue. In stead we now
cancel any scheduled continuation, thaw the UI immediately, and switch
the menus and gameMode to ncp straight away.

diff --git a/backend.c b/backend.c
index f420925..75b1529 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -8363,7 +8363,7 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
 
     /*
      * If chess program startup fails, exit with an error message.
-     * Attempts to recover here are futile.
+     * Attempts to recover here are futile. [HGM] Well, we try anyway
      */
     if ((StrStr(message, "unknown host") != NULL)
        || (StrStr(message, "No remote directory") != NULL)
@@ -8377,7 +8377,14 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
                _(cps->which), cps->program, cps->host, message);
        RemoveInputSource(cps->isr);
        if(appData.icsActive) DisplayFatalError(buf1, 0, 1); else {
-           if(cps == &first) appData.noChessProgram = TRUE;
+           if(cps == &first) {
+               appData.noChessProgram = TRUE;
+               gameMode = MachinePlaysBlack; ModeHighlight(); // kludge to unmark Machine Black menu
+               gameMode = BeginningOfGame; ModeHighlight();
+               SetNCPMode();
+           }
+           if(GetDelayedEvent()) CancelDelayedEvent(), ThawUI(); // [HGM] cancel remaining loading effort scheduled after feature timeout
+           DisplayMessage("", ""); // erase waiting message
            DisplayError(buf1, 0);
        }
        return;