From 148a53fde47be05f875928dc050b989198c5425c Mon Sep 17 00:00:00 2001
From: H.G.Muller <hgm@hgm-xboard.(none)>
Date: Tue, 4 Mar 2014 10:40:50 +0100
Subject: [PATCH] Implement XBoard memory command

The hash-table allocation in Initialize_data was moved to a separate
routine AllocateTT, which is now also called in response to the XBoard
memory command.
---
 gnushogi/commondsp.c   |   13 ++++++-
 gnushogi/gnushogi.h    |    1 +
 gnushogi/init-common.c |   92 ++++++++++++++++++++++++++++--------------------
 3 files changed, 67 insertions(+), 39 deletions(-)

diff --git a/gnushogi/commondsp.c b/gnushogi/commondsp.c
index e35698d..4cdc459 100644
--- a/gnushogi/commondsp.c
+++ b/gnushogi/commondsp.c
@@ -1677,7 +1677,7 @@ InputCommand(char *command, int root)
                    "shogi"
 #endif
                 );
-            printf("debug=1 setboard=0 sigint=0 done=1\n");
+            printf("debug=1 setboard=0 sigint=0 memory=1 done=1\n");
         }
         else if (strcmp(s, ".") == 0)
         {   // periodic update request of analysis info: send stat01 info
@@ -1711,6 +1711,17 @@ InputCommand(char *command, int root)
         {
             ok = true;
         }
+#if ttblsz
+        else if (strcmp(s, "memory") == 0)
+        {
+            unsigned int mem, size, t = 1;
+            sscanf(sx, "memory %d", &mem);
+            if(mem > 2048) mem = 2048; /* prevent integer overflow for > 2GB hash */
+            size = (mem << 20) / sizeof(struct hashentry) - rehash;
+            while(t <= size/4) t <<= 1;
+            AllocateTT(t);
+        }
+#endif
         else if (strcmp(s, "go") == 0)
         {
             ok = true;
diff --git a/gnushogi/gnushogi.h b/gnushogi/gnushogi.h
index dd5c21e..d40c3ac 100644
--- a/gnushogi/gnushogi.h
+++ b/gnushogi/gnushogi.h
@@ -912,6 +912,7 @@ extern void Initialize_eval(void); /* eval.c */
 extern void NewGame(void);
 extern void GetOpenings(void);
 extern int  OpeningBook(unsigned short *hint);
+extern int  AllocateTT(int size); /* init-common.c */
 
 typedef enum
 {
diff --git a/gnushogi/init-common.c b/gnushogi/init-common.c
index 1f71994..0d89dae 100644
--- a/gnushogi/init-common.c
+++ b/gnushogi/init-common.c
@@ -136,6 +136,59 @@ const small_short side_of_ptype[NO_PTYPE_PIECES] =
     white, white
 };
 
+int
+AllocateTT(int size)
+{
+    int n = sizeof(struct hashentry)*(size + rehash);
+    static int oldSize;
+    int doit = true;
+
+    if(oldSize == size) return use_ttable;
+    oldSize = ttblsize = size;
+
+    if(ttable[0]) free(ttable[0]);
+    if(ttable[1]) free(ttable[1]);
+
+    while (doit && ttblsize > MINTTABLE)
+    {
+        ttable[0] = malloc(n);  /* FIXME: cast to the correct type. */
+        ttable[1] = ttable[0] ? malloc(n) : NULL;
+
+        if (!ttable[0] || !ttable[1])
+        {
+            if (!ttable[0])
+                free(ttable[0]);
+
+            if (!ttable[1])
+                free(ttable[1]);
+
+            ttblsize = ttblsize >> 1;
+            n = sizeof(struct hashentry) * (ttblsize + rehash);
+        }
+        else
+        {
+            doit = false;
+        }
+    }
+
+    if (ttblsize <= MINTTABLE)
+    {
+        use_ttable = false;
+    }
+
+    if (use_ttable)
+    {
+        /* CHECKME: is the precedence here correct? */
+        /* ttbllimit = ttblsize << 1 - ttblsize >> 2; */
+        ttbllimit = (ttblsize << 1) - (ttblsize >> 2);
+    }
+    else
+    {
+        ttable[0] = ttable[1] = NULL;
+    }
+
+    return use_ttable;
+}
 
 int
 Initialize_data(void)
@@ -143,7 +196,6 @@ Initialize_data(void)
     size_t n;
     int i;
     char buffer[60];
-    int doit = true;
 
     {
         small_short x = -1;
@@ -295,47 +347,11 @@ Initialize_data(void)
     if (rehash < 0)
         rehash = MAXrehash;
 
-    n = sizeof(struct hashentry)*(ttblsize + rehash);
-
-    while (doit && ttblsize > MINTTABLE)
-    {
-        ttable[0] = malloc(n);  /* FIXME: cast to the correct type. */
-        ttable[1] = ttable[0] ? malloc(n) : NULL;
-
-        if (!ttable[0] || !ttable[1])
-        {
-            if (!ttable[0])
-                free(ttable[0]);
-
-            if (!ttable[1])
-                free(ttable[1]);
-
-            ttblsize = ttblsize >> 1;
-            n = sizeof(struct hashentry) * (ttblsize + rehash);
-        }
-        else
-        {
-            doit = false;
-        }
-    }
-
-    if (ttblsize <= MINTTABLE)
-    {
-        use_ttable = false;
-    }
-
-    if (use_ttable)
-    {
-        /* CHECKME: is the precedence here correct? */
-        /* ttbllimit = ttblsize << 1 - ttblsize >> 2; */
-        ttbllimit = (ttblsize << 1) - (ttblsize >> 2);
-    }
-    else
+    if (!AllocateTT(ttblsize))
     {
         sprintf(buffer, "Cannot allocate %ld bytes for transposition table",
                 (long)(2 * n));
         dsp->ShowMessage(buffer);
-        ttable[0] = ttable[1] = NULL;
     }
 #endif /* ttblsz */
 
-- 
1.7.0.4