From 9798d0e093e1ea35cbea11b5f0846d09d1e1ba34 Mon Sep 17 00:00:00 2001
From: H.G. Muller <h.g.muller@hccnet.nl>
Date: Sun, 30 Dec 2012 15:06:33 +0100
Subject: [PATCH] Resend engine-defined options after reuse=0 reload

When the engine process is re-spawned for a new game under -xreuse setting,
any alteration of engine settings brought about through the Engine Settings
dialogs would be lost, and revert to the engine's default. This is now fixed
by re-sending all options (known from the previous load of the same engine)
with the current settings immediately after "protover 2", and ignoring the
engine's option features. Rather than clearing the option list, and
redefining it from the option features.
---
 backend.c |   39 +++++++++++++++++++++++++++++++++++++--
 backend.h |    1 +
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/backend.c b/backend.c
index 3ab07f9..21ea333 100644
--- a/backend.c
+++ b/backend.c
@@ -786,6 +786,7 @@ InitEngine (ChessProgramState *cps, int n)
     cps->analysisSupport = 2; /* detect */
     cps->analyzing = FALSE;
     cps->initDone = FALSE;
+    cps->reload = FALSE;
 
     /* New features added by Tord: */
     cps->useFEN960 = FALSE;
@@ -9941,6 +9942,33 @@ InitChessProgram (ChessProgramState *cps, int setup)
 
 
 void
+ResendOptions (ChessProgramState *cps)
+{ // send the stored value of the options
+  int i;
+  char buf[MSG_SIZ];
+  Option *opt = cps->option;
+  for(i=0; i<cps->nrOptions; i++, opt++) {
+      switch(opt->type) {
+        case Spin:
+        case Slider:
+        case CheckBox:
+	    snprintf(buf, MSG_SIZ, "option %s=%d\n", opt->name, opt->value);
+          break;
+        case ComboBox:
+          snprintf(buf, MSG_SIZ, "option %s=%s\n", opt->name, opt->choice[opt->value]);
+          break;
+        default:
+	    snprintf(buf, MSG_SIZ, "option %s=%s\n", opt->name, opt->textValue);
+          break;
+        case Button:
+        case SaveButton:
+          continue;
+      }
+      SendToProgram(buf, cps);
+  }
+}
+
+void
 StartChessProgram (ChessProgramState *cps)
 {
     char buf[MSG_SIZ];
@@ -9980,9 +10008,12 @@ StartChessProgram (ChessProgramState *cps)
     cps->isr = AddInputSource(cps->pr, TRUE, ReceiveFromProgram, cps);
     if (cps->protocolVersion > 1) {
       snprintf(buf, MSG_SIZ, "xboard\nprotover %d\n", cps->protocolVersion);
-      cps->nrOptions = 0; // [HGM] options: clear all engine-specific options
-      cps->comboCnt = 0;  //                and values of combo boxes
+      if(!cps->reload) { // do not clear options when reloading because of -xreuse
+        cps->nrOptions = 0; // [HGM] options: clear all engine-specific options
+        cps->comboCnt = 0;  //                and values of combo boxes
+      }
       SendToProgram(buf, cps);
+      if(cps->reload) ResendOptions(cps);
     } else {
       SendToProgram("xboard\n", cps);
     }
@@ -10807,6 +10838,7 @@ GameEnds (ChessMove result, char *resultDetails, int whosays)
 	    SendToProgram("quit\n", &first);
             DoSleep( appData.delayAfterQuit );
 	    DestroyChildProcess(first.pr, first.useSigterm);
+	    first.reload = TRUE;
 	}
 	first.pr = NoProc;
     }
@@ -10832,6 +10864,7 @@ GameEnds (ChessMove result, char *resultDetails, int whosays)
 	    SendToProgram("quit\n", &second);
             DoSleep( appData.delayAfterQuit );
 	    DestroyChildProcess(second.pr, second.useSigterm);
+	    second.reload = TRUE;
 	}
 	second.pr = NoProc;
     }
@@ -15994,6 +16027,7 @@ FeatureDone (ChessProgramState *cps, int val)
     ScheduleDelayedEvent(cb, val ? 1 : 3600000);
   }
   cps->initDone = val;
+  if(val) cps->reload = FALSE;
 }
 
 /* Parse feature command from engine */
@@ -16056,6 +16090,7 @@ ParseFeatures (char *args, ChessProgramState *cps)
     if (BoolFeature(&p, "smp", &cps->maxCores, cps)) continue;
     if (StringFeature(&p, "egt", cps->egtFormats, cps)) continue;
     if (StringFeature(&p, "option", buf, cps)) {
+	if(cps->reload) continue; // we are reloading because of xreuse
 	FREE(cps->option[cps->nrOptions].name);
 	cps->option[cps->nrOptions].name = malloc(MSG_SIZ);
 	safeStrCpy(cps->option[cps->nrOptions].name, buf, MSG_SIZ);
diff --git a/backend.h b/backend.h
index c9f14bc..e62b9b1 100644
--- a/backend.h
+++ b/backend.h
@@ -405,6 +405,7 @@ typedef struct XB_CPS {
     void *programLogo; /* [HGM] logo: bitmap of the logo                    */
     char *fenOverride; /* [HGM} FRC: force FEN casling & ep fields by hand  */
     char userError;    /* [HGM] crash: flag to suppress fatal-error messages*/
+    char reload;       /* [HGM] options: flag to resend options with xreuse */
 } ChessProgramState;
 
 extern ChessProgramState first, second;
-- 
1.7.0.4