[gnugo-devel] resign support in obsolete GTP version 1 commands

[Gunnar Farnebäck]

The GTP command genmove can return "resign" if resignation is enabled
in the engine and the position is sufficiently hopeless. This is all
in accordance with the GTP version 2 specification of genmove.
However, also the obsolete GTP version 1 commands genmove_black and
genmove_white can currently return "resign", which I don't think makes
sense. GTP version 1 is defined by the implementation in GNU Go 3.0,
which would never resign, so this changes the behaviour of a command
which is strictly version 1. Also any application which still uses GTP
version 1 is almost certain not to be able to handle a resign
response.

This patch removes resignation from genmove_black and genmove_white.

- resignation option reverted from GTP commands genmove_black and
  genmove_white

/Gunnar

Index: doc/gtp-commands.texi
===================================================================
RCS file: /cvsroot/gnugo/gnugo/doc/gtp-commands.texi,v
retrieving revision 1.22
diff -u -r1.22 gtp-commands.texi
--- doc/gtp-commands.texi       23 Apr 2004 00:23:29 -0000      1.22
+++ doc/gtp-commands.texi       11 Nov 2004 05:18:26 -0000
@@ -815,7 +815,7 @@
  Function:  Generate and play the supposedly best black move.
  Arguments: none
  Fails:     never
- Returns:   a move coordinate or "PASS" (or "resign" if resignation_allowed).
+ Returns:   a move coordinate or "PASS"
 
  Status:    Obsolete GTP version 1 command.
 
@@ -829,7 +829,7 @@
  Function:  Generate and play the supposedly best white move.
  Arguments: none
  Fails:     never
- Returns:   a move coordinate (or "PASS")
+ Returns:   a move coordinate or "PASS"
 
  Status:    Obsolete GTP version 1 command.
 
@@ -843,7 +843,7 @@
  Function:  Generate and play the supposedly best move for either color.
  Arguments: color to move
  Fails:     invalid color
- Returns:   a move coordinate (or "PASS")
+ Returns:   a move coordinate or "PASS" (or "resign" if resignation_allowed)
 
  Status:    GTP version 2 standard command.
 
Index: interface/play_gtp.c
===================================================================
RCS file: /cvsroot/gnugo/gnugo/interface/play_gtp.c,v
retrieving revision 1.155
diff -u -r1.155 play_gtp.c
--- interface/play_gtp.c        8 Nov 2004 04:10:02 -0000       1.155
+++ interface/play_gtp.c        11 Nov 2004 05:18:27 -0000
@@ -2342,7 +2342,7 @@
 /* Function:  Generate and play the supposedly best black move.
  * Arguments: none
  * Fails:     never
- * Returns:   a move coordinate or "PASS" (or "resign" if resignation_allowed).
+ * Returns:   a move coordinate or "PASS"
  *
  * Status:    Obsolete GTP version 1 command.
  */
@@ -2350,16 +2350,12 @@
 gtp_genmove_black(char *s)
 {
   int move;
-  int resign;
   UNUSED(s);
 
   if (stackp > 0)
     return gtp_failure("genmove cannot be called when stackp > 0");
 
-  move = genmove(BLACK, NULL, &resign);
-
-  if (resign)
-    return gtp_success("resign");
+  move = genmove(BLACK, NULL, NULL);
 
   play_move(move, BLACK);
 
@@ -2371,7 +2367,7 @@
 /* Function:  Generate and play the supposedly best white move.
  * Arguments: none
  * Fails:     never
- * Returns:   a move coordinate (or "PASS")
+ * Returns:   a move coordinate or "PASS"
  *
  * Status:    Obsolete GTP version 1 command.
  */
@@ -2379,16 +2375,12 @@
 gtp_genmove_white(char *s)
 {
   int move;
-  int resign;
   UNUSED(s);
 
   if (stackp > 0)
     return gtp_failure("genmove cannot be called when stackp > 0");
 
-  move = genmove(WHITE, NULL, &resign);
-
-  if (resign)
-    return gtp_success("resign");
+  move = genmove(WHITE, NULL, NULL);
 
   play_move(move, WHITE);
 
@@ -2400,7 +2392,7 @@
 /* Function:  Generate and play the supposedly best move for either color.
  * Arguments: color to move
  * Fails:     invalid color
- * Returns:   a move coordinate (or "PASS")
+ * Returns:   a move coordinate or "PASS" (or "resign" if resignation_allowed)
  *
  * Status:    GTP version 2 standard command.
  */