new forceIllegalMoves option

The -forceIllegalMoves option uses setboard or edit to force a position when an engine refuses the move leading to it by an "Illegal Move" message.
Especially for engines using the edit command this was a bit tricky, because of the a2a3 kludge to avoid using the white and black commands.

diff --git a/backend.c b/backend.c
index 304acc2..5fb842c 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -6390,6 +6390,29 @@ if(appData.debugMode) fprintf(debugFP, "nodes = %d, %lld\n", (int) programStats.
        }
 #endif
        if (pausing) PauseEvent();
+      if(appData.forceIllegal) {
+           // [HGM] illegal: machine refused move; force position after move into it
+          SendToProgram("force\n", cps);
+          if(!cps->useSetboard) { // hideous kludge on kludge, because SendBoard sucks.
+               // we have a real problem now, as SendBoard will use the a2a3 kludge
+               // when black is to move, while there might be nothing on a2 or black
+               // might already have the move. So send the board as if white has the move.
+               // But first we must change the stm of the engine, as it refused the last move
+               SendBoard(cps, 0); // always kludgeless, as white is to move on boards[0]
+               if(WhiteOnMove(forwardMostMove)) {
+                   SendToProgram("a7a6\n", cps); // for the engine black still had the move
+                   SendBoard(cps, forwardMostMove); // kludgeless board
+               } else {
+                   SendToProgram("a2a3\n", cps); // for the engine white still had the move
+                   CopyBoard(boards[forwardMostMove+1], boards[forwardMostMove]);
+                   SendBoard(cps, forwardMostMove+1); // kludgeless board
+               }
+          } else SendBoard(cps, forwardMostMove); // FEN case, also sets stm properly
+           if(gameMode == MachinePlaysWhite || gameMode == MachinePlaysBlack ||
+                gameMode == TwoMachinesPlay)
+              SendToProgram("go\n", cps);
+           return;
+      } else
        if (gameMode == PlayFromGameFile) {
            /* Stop reading this game file */
            gameMode = EditGame;

diff --git a/common.h b/common.h
index fb218bc..83c6837 100644 (file)
--- a/common.h
+++ b/common.h
@@ -601,6 +601,7 @@ typedef struct {
     char *fenOverride1;
     char *fenOverride2;
     Boolean keepAlive;  /* [HGM] alive     */
+    Boolean forceIllegal;/*[HGM] illegal   */
 } AppData, *AppDataPtr;
 
 /* [AS] PGN tags (for showing in the game list) */

diff --git a/winboard/winboard.c b/winboard/winboard.c
index 3b2dd29..bbd8563 100644 (file)
--- a/winboard/winboard.c
+++ b/winboard/winboard.c
@@ -1339,6 +1339,7 @@ ArgDescriptor argDescriptors[] = {
   { "secondNeedsNoncompliantFEN", ArgString, (LPVOID) &appData.fenOverride2, FALSE },\r
   { "keepAlive", ArgInt, (LPVOID) &appData.keepAlive, FALSE },\r
   { "icstype", ArgInt, (LPVOID) &ics_type, FALSE },\r
+  { "forceIllegalMoves", ArgTrue, (LPVOID) &appData.forceIllegal, FALSE },\r
 \r
 #ifdef ZIPPY\r
   { "zippyTalk", ArgBoolean, (LPVOID) &appData.zippyTalk, FALSE },\r