Fix engine stall on perpetual-check evasion
[xboard.git] / backend.c
index b2a6a01..53799ec 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -1351,6 +1351,19 @@ establish()
     }
 }
 
+void EscapeExpand(char *p, char *q)
+{      // [HGM] initstring: routine to shape up string arguments
+       while(*p++ = *q++) if(p[-1] == '\\')
+           switch(*q++) {
+               case 'n': p[-1] = '\n'; break;
+               case 'r': p[-1] = '\r'; break;
+               case 't': p[-1] = '\t'; break;
+               case '\\': p[-1] = '\\'; break;
+               case 0: *p = 0; return;
+               default: p[-1] = q[-1]; break;
+           }
+}
+
 void
 show_bytes(fp, buf, count)
      FILE *fp;
@@ -1983,7 +1996,7 @@ void
 VariantSwitch(Board board, VariantClass newVariant)
 {
    int newHoldingsWidth, newWidth = 8, newHeight = 8, i, j;
-   Board oldBoard;
+   static Board oldBoard;
 
    startedFromPositionFile = FALSE;
    if(gameInfo.variant == newVariant) return;
@@ -3842,7 +3855,7 @@ ParseBoard12(string)
     }
     
     if((gameMode == IcsPlayingWhite || gameMode == IcsPlayingBlack)
-        && newGameMode == IcsObserving && appData.bgObserve) {
+        && newGameMode == IcsObserving && gamenum != ics_gamenum && appData.bgObserve) {
       // [HGM] bughouse: don't act on alien boards while we play. Just parse the board and save it */
       char *toSqr;
       for (k = 0; k < ranks; k++) {
@@ -6772,7 +6785,7 @@ Adjudicate(ChessProgramState *cps)
                    || NrWN==2 || NrBN==2     /* KNNK */
                    || NrWN+NrWB == 1 && NrBN+NrBB == 1 /* KBKN, KBKB, KNKN */
                   ) ) {
-                     if(canAdjudicate && --moveCount < 0 && appData.trivialDraws)
+                     if(--moveCount < 0 && appData.trivialDraws && canAdjudicate)
                      {    /* if the first 3 moves do not show a tactical win, declare draw */
                          if(engineOpponent) {
                            SendToProgram("force\n", engineOpponent); // suppress reply
@@ -6823,14 +6836,11 @@ Adjudicate(ChessProgramState *cps)
                                 boards[forwardMostMove][CASTLING][4] != boards[k][CASTLING][4] )
                                    rights++;
                         }
-                        if( canAdjudicate && rights == 0 && ++count > appData.drawRepeats-2
+                        if( rights == 0 && ++count > appData.drawRepeats-2 && canAdjudicate
                             && appData.drawRepeats > 1) {
                              /* adjudicate after user-specified nr of repeats */
-                            if(engineOpponent) {
-                              SendToProgram("force\n", engineOpponent); // suppress reply
-                              SendMoveToProgram(forwardMostMove-1, engineOpponent); /* make sure opponent gets to see move */
-                            }
-                             ShowMove(fromX, fromY, toX, toY); /*updates currentMove*/
+                            int result = GameIsDrawn;
+                            char *details = "XBoard adjudication: repetition draw";
                             if(gameInfo.variant == VariantXiangqi && appData.testLegality) { 
                                // [HGM] xiangqi: check for forbidden perpetuals
                                int m, ourPerpetual = 1, hisPerpetual = 1;
@@ -6843,27 +6853,31 @@ Adjudicate(ChessProgramState *cps)
                                if(appData.debugMode) fprintf(debugFP, "XQ perpetual test, our=%d, his=%d\n",
                                                                        ourPerpetual, hisPerpetual);
                                if(ourPerpetual && !hisPerpetual) { // we are actively checking him: forfeit
-                                   GameEnds( WhiteOnMove(forwardMostMove) ? WhiteWins : BlackWins, 
-                                          "Xboard adjudication: perpetual checking", GE_XBOARD );
-                                   return 1;
-                               }
-                               if(hisPerpetual && !ourPerpetual)   // he is checking us, but did not repeat yet
+                                   result = WhiteOnMove(forwardMostMove) ? WhiteWins : BlackWins;
+                                   details = "Xboard adjudication: perpetual checking";
+                               } else
+                               if(hisPerpetual && !ourPerpetual) { // he is checking us, but did not repeat yet
                                    break; // (or we would have caught him before). Abort repetition-checking loop.
+                               } else
                                // Now check for perpetual chases
                                if(!ourPerpetual && !hisPerpetual) { // no perpetual check, test for chase
                                    hisPerpetual = PerpetualChase(k, forwardMostMove);
                                    ourPerpetual = PerpetualChase(k+1, forwardMostMove);
                                    if(ourPerpetual && !hisPerpetual) { // we are actively chasing him: forfeit
-                                       GameEnds( WhiteOnMove(forwardMostMove) ? WhiteWins : BlackWins, 
-                                                     "Xboard adjudication: perpetual chasing", GE_XBOARD );
-                                       return 1;
-                                   }
+                                       result = WhiteOnMove(forwardMostMove) ? WhiteWins : BlackWins;
+                                       details = "Xboard adjudication: perpetual chasing";
+                                   } else
                                    if(hisPerpetual && !ourPerpetual)   // he is chasing us, but did not repeat yet
                                        break; // Abort repetition-checking loop.
                                }
                                // if neither of us is checking or chasing all the time, or both are, it is draw
                             }
-                             GameEnds( GameIsDrawn, "Xboard adjudication: repetition draw", GE_XBOARD );
+                            if(engineOpponent) {
+                              SendToProgram("force\n", engineOpponent); // suppress reply
+                              SendMoveToProgram(forwardMostMove-1, engineOpponent); /* make sure opponent gets to see move */
+                            }
+                             ShowMove(fromX, fromY, toX, toY); /*updates currentMove*/
+                             GameEnds( result, details, GE_XBOARD );
                              return 1;
                         }
                         if( rights == 0 && count > 1 ) /* occurred 2 or more times before */
@@ -7334,11 +7348,13 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
      * Look for communication commands
      */
     if (!strncmp(message, "telluser ", 9)) {
+       EscapeExpand(message+9, message+9); // [HGM] esc: allow escape sequences in popup box
        DisplayNote(message + 9);
        return;
     }
     if (!strncmp(message, "tellusererror ", 14)) {
        cps->userError = 1;
+       EscapeExpand(message+14, message+14); // [HGM] esc: allow escape sequences in popup box
        DisplayError(message + 14, 0);
        return;
     }
@@ -7792,6 +7808,7 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
        }
 
        if (!ignore) {
+           ChessProgramStats tempStats = programStats; // [HGM] info: filter out info lines
            buf1[0] = NULLCHAR;
            if (sscanf(message, "%d%c %d %d " u64Display " %[^\n]\n",
                       &plylev, &plyext, &curscore, &time, &nodes, buf1) >= 5) {
@@ -7813,11 +7830,11 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
                 }
 
 
-               programStats.depth = plylev;
-               programStats.nodes = nodes;
-               programStats.time = time;
-               programStats.score = curscore;
-               programStats.got_only_move = 0;
+               tempStats.depth = plylev;
+               tempStats.nodes = nodes;
+               tempStats.time = time;
+               tempStats.score = curscore;
+               tempStats.got_only_move = 0;
 
                if(cps->nps >= 0) { /* [HGM] nps: use engine nodes or time to decrement clock */
                        int ticklen;
@@ -7834,31 +7851,34 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
 
                /* Buffer overflow protection */
                if (buf1[0] != NULLCHAR) {
-                   if (strlen(buf1) >= sizeof(programStats.movelist)
+                   if (strlen(buf1) >= sizeof(tempStats.movelist)
                        && appData.debugMode) {
                        fprintf(debugFP,
                                "PV is too long; using the first %u bytes.\n",
-                               (unsigned) sizeof(programStats.movelist) - 1);
+                               (unsigned) sizeof(tempStats.movelist) - 1);
                    }
 
-                    safeStrCpy( programStats.movelist, buf1, sizeof(programStats.movelist) );
+                    safeStrCpy( tempStats.movelist, buf1, sizeof(tempStats.movelist) );
                } else {
-                   sprintf(programStats.movelist, " no PV\n");
+                   sprintf(tempStats.movelist, " no PV\n");
                }
 
-               if (programStats.seen_stat) {
-                   programStats.ok_to_send = 1;
+               if (tempStats.seen_stat) {
+                   tempStats.ok_to_send = 1;
                }
 
-               if (strchr(programStats.movelist, '(') != NULL) {
-                   programStats.line_is_book = 1;
-                   programStats.nr_moves = 0;
-                   programStats.moves_left = 0;
+               if (strchr(tempStats.movelist, '(') != NULL) {
+                   tempStats.line_is_book = 1;
+                   tempStats.nr_moves = 0;
+                   tempStats.moves_left = 0;
                } else {
-                   programStats.line_is_book = 0;
+                   tempStats.line_is_book = 0;
                }
 
-                SendProgramStatsToFrontend( cps, &programStats );
+                   if(tempStats.score != 0 || tempStats.nodes != 0 || tempStats.time != 0)
+                       programStats = tempStats; // [HGM] info: only set stats if genuine PV and not an info line
+
+                SendProgramStatsToFrontend( cps, &tempStats );
 
                 /* 
                     [AS] Protect the thinkOutput buffer from overflow... this
@@ -15211,3 +15231,4 @@ LoadVariation(int index, char *text)
        CommentPopDown();
        ToNrEvent(currentMove+1);
 }
+