Fix crash on loading garbage game file

The code to cache games was not resistant to moves before a valid
game start, or a game filewithout any games at all.

diff --git a/gamelist.c b/gamelist.c
index fb10fbe..188fdf6 100644 (file)
--- a/gamelist.c
+++ b/gamelist.c
@@ -342,7 +342,7 @@ struct {
                toY = currentMoveString[3] - ONE;
                plyNr++;
                ApplyMove(fromX, fromY, toX, toY, currentMoveString[4], boards[scratch]);
-               if(currentListGame->moves) PackMove(fromX, fromY, toX, toY, boards[scratch][toY][toX]);
+               if(currentListGame && currentListGame->moves) PackMove(fromX, fromY, toX, toY, boards[scratch][toY][toX]);
            break;
         case WhiteWins: // [HGM] rescom: save last comment as result details
         case BlackWins:
@@ -368,6 +368,7 @@ struct {
     }
     while (cm != (ChessMove) 0);
 
+ if(currentListGame) {
     if(!currentListGame->moves) DisplayError("Game cache overflowed\nPosition-searching might not work properly", 0);
 
     if (appData.debugMode) {
@@ -380,6 +381,7 @@ struct {
            PrintPGNTags(debugFP, &currentListGame->gameInfo);
        }
     }
+  }
 GetTimeMark(&t2);printf("GameListBuild %d msec\n", SubtractTimeMarks(&t2,&t));
     quickFlag = 0;
     PackGame(boards[scratch]); // for appending end-of-game marker.