Catch unknown engine in tourney games

When an XBoard instance is playing on a tourney it can happen that it is
using a settings file with an engine list not yet containing a certain
participant, because that participant was just installed in the instance
that created the tourney file, but it did not save those modifications yet.
This error is now caught, and leads to an error popup and stopping of the
tourney play. This error was made non-fatal to allow the user to decide
if he wants to quit with or without saving the settings (which, after all,
does not seem up-to-date).

diff --git a/backend.c b/backend.c
index 2028269..dd5106f 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -10346,6 +10346,13 @@ SetPlayer (int player, char *p)
        ParseArgsFromString(resetOptions); appData.fenOverride[0] = NULL; appData.pvSAN[0] = FALSE;
        appData.firstHasOwnBookUCI = !appData.defNoBook; appData.protocolVersion[0] = PROTOVER;
        ParseArgsFromString(buf);
+    } else { // no engine with this nickname is installed!
+       snprintf(buf, MSG_SIZ, _("No engine %s is installed"), engineName);
+       ReserveGame(nextGame, ' '); // unreserve game and drop out of match mode with error
+       matchMode = FALSE; appData.matchGames = matchGame = roundNr = 0;
+       ModeHighlight();
+       DisplayError(buf, 0);
+       return 0;
     }
     free(engineName);
     return i;
@@ -10420,7 +10427,7 @@ int
 NextTourneyGame (int nr, int *swapColors)
 {   // !!!major kludge!!! fiddle appData settings to get everything in order for next tourney game
     char *p, *q;
-    int whitePlayer, blackPlayer, firstBusy=1000000000, syncInterval = 0, nPlayers;
+    int whitePlayer, blackPlayer, firstBusy=1000000000, syncInterval = 0, nPlayers, OK = 1;
     FILE *tf;
     if(appData.tourneyFile[0] == NULLCHAR) return 1; // no tourney, always allow next game
     tf = fopen(appData.tourneyFile, "r");
@@ -10472,18 +10479,18 @@ NextTourneyGame (int nr, int *swapColors)
     // redefine engines, engine dir, etc.
     NamesToList(firstChessProgramNames, command, mnemonic, "all"); // get mnemonics of installed engines
     if(first.pr == NoProc) {
-      SetPlayer(whitePlayer, appData.participants); // find white player amongst it, and parse its engine line
+      if(!SetPlayer(whitePlayer, appData.participants)) OK = 0; // find white player amongst it, and parse its engine line
       InitEngine(&first, 0);  // initialize ChessProgramStates based on new settings.
     }
     if(second.pr == NoProc) {
       SwapEngines(1);
-      SetPlayer(blackPlayer, appData.participants); // find black player amongst it, and parse its engine line
+      if(!SetPlayer(blackPlayer, appData.participants)) OK = 0; // find black player amongst it, and parse its engine line
       SwapEngines(1);         // and make that valid for second engine by swapping
       InitEngine(&second, 1);
     }
     CommonEngineInit();     // after this TwoMachinesEvent will create correct engine processes
     UpdateLogos(FALSE);     // leave display to ModeHiglight()
-    return 1;
+    return OK;
 }
 
 void