Implement new way of pondering

The think and ponder searches are unified, so a search that starts as
pondering can continue without interruption as thinking on a ponder hit.

diff --git a/hachu.c b/hachu.c
index 609f05e..522aa84 100644 (file)
--- a/hachu.c
+++ b/hachu.c
@@ -2263,14 +2263,6 @@ MapFromScratch(attacks);
 }\r
 \r
 \r
-void\r
-PonderUntilInput (int stm)\r
-{\r
-MapFromScratch(attacks);\r
-  repCnt = 0; abortFlag = -1;\r
-  Search(-INF-1, INF+1, rootEval, maxDepth, sup1, sup2);\r
-}\r
- \r
     int TakeBack(int n)\r
     { // reset the game and then replay it to the desired point\r
       int last, stm;\r
@@ -2345,14 +2337,19 @@ printf("# in (mode = %d,%d): %s\n", root, abortFlag, command);
         *inBuf = 0;\r
 \r
         if(listEnd == 0) ListMoves();   // always maintain a list of legal moves in root position\r
-\r
-        abortFlag = 0;\r
-        if(stm == engineSide) {         // if it is the engine's turn to move, set it thinking, and let it move\r
-     \r
+        abortFlag = -(ponder && WHITE+BLACK-stm == engineSide && moveNr); // pondering and opponent on move\r
+        if(stm == engineSide || abortFlag && ponderMove) {      // if it is the engine's turn to move, set it thinking, and let it move\r
+          if(abortFlag) {\r
+            stm = MakeMove2(stm, ponderMove);                           // for pondering, play speculative move\r
+            gameMove[moveNr++] = ponderMove;                            // remember in game\r
+            sprintf(ponderMoveText, "%s\n", MoveToText(ponderMove, 0)); // for detecting ponder hits\r
+          } else SetSearchTimes(10*timeLeft);                           // for thinking, schedule end time\r
 pboard(board);\r
-          SetSearchTimes(10*timeLeft);\r
           score = SearchBestMove(&move, &ponderMove);\r
-\r
+          if(abortFlag == 1) { // ponder search was interrupted (and no hit)\r
+            UnMake2(INVALID); moveNr--; stm ^= WHITE;    // take ponder move back if we made one\r
+            abortFlag = 0;\r
+          } else\r
           if(move == INVALID) {         // game apparently ended\r
             int kcapt = 0, xstm = stm ^ WHITE, king, k = p[king=royal[xstm]].pos;\r
             if( k != ABSENT) { // test if King capture possible\r
@@ -2375,24 +2372,15 @@ pboard(board);
             gameMove[moveNr++] = move;   // remember game\r
             printf("move %s\n", MoveToText(move, 1));\r
             listEnd = 0;\r
-            continue;\r
+            continue;                    // go check if we should ponder\r
           }\r
-        }\r
-\r
-        fflush(stdout); // make sure everything is printed before we do something that might take time\r
-\r
-        // now it is not our turn (anymore)\r
-        if(engineSide == ANALYZE) {       // in analysis, we always ponder the position\r
-            PonderUntilInput(stm);\r
         } else\r
-        if(engineSide != NONE && ponder == ON && moveNr != 0) { // ponder while waiting for input\r
-          if(ponderMove == INVALID) {     // if we have no move to ponder on, ponder the position\r
-            PonderUntilInput(stm);\r
-          } else {\r
-            int newStm = MakeMove2(stm, ponderMove);\r
-            PonderUntilInput(newStm);\r
-            UnMake2(ponderMove);\r
-          }\r
+        if(engineSide == ANALYZE || abortFlag) { // in analysis, we always ponder the position\r
+            Move dummy;\r
+            *ponderMoveText = 0; // forces miss on any move\r
+            abortFlag = -1;      // set pondering\r
+            SearchBestMove(&dummy, &dummy);\r
+            abortFlag = 0;       //\r
         }\r
 \r
         fflush(stdout);         // make sure everything is printed before we do something that might take time\r