--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ode/inc/obstack.h	Tue Feb 02 01:00:49 2010 +0200
@@ -0,0 +1,68 @@
+/*************************************************************************
+ *                                                                       *
+ * Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith.       *
+ * All rights reserved.  Email: russ@q12.org   Web: www.q12.org          *
+ *                                                                       *
+ * This library is free software; you can redistribute it and/or         *
+ * modify it under the terms of EITHER:                                  *
+ *   (1) The GNU Lesser General Public License as published by the Free  *
+ *       Software Foundation; either version 2.1 of the License, or (at  *
+ *       your option) any later version. The text of the GNU Lesser      *
+ *       General Public License is included with this library in the     *
+ *       file LICENSE.TXT.                                               *
+ *   (2) The BSD-style license that is included with this library in     *
+ *       the file LICENSE-BSD.TXT.                                       *
+ *                                                                       *
+ * This library is distributed in the hope that it will be useful,       *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *
+ * LICENSE.TXT and LICENSE-BSD.TXT for more details.                     *
+ *                                                                       *
+ *************************************************************************/
+
+#ifndef _ODE_OBSTACK_H_
+#define _ODE_OBSTACK_H_
+
+#include "object.h" 
+
+// each obstack Arena pointer points to a block of this many bytes
+#define dOBSTACK_ARENA_SIZE 16384
+
+
+struct dObStack : public dBase {
+  struct Arena {
+    Arena *next;	// next arena in linked list
+    size_t used;		// total number of bytes used in this arena, counting
+  };			//   this header
+
+  Arena *first;		// head of the arena linked list. 0 if no arenas yet
+  Arena *last;		// arena where blocks are currently being allocated
+
+  // used for iterator
+  Arena *current_arena;
+  size_t current_ofs;
+
+  dObStack();
+  ~dObStack();
+
+  void *alloc (int num_bytes);
+  // allocate a block in the last arena, allocating a new arena if necessary.
+  // it is a runtime error if num_bytes is larger than the arena size.
+
+  void freeAll();
+  // free all blocks in all arenas. this does not deallocate the arenas
+  // themselves, so future alloc()s will reuse them.
+
+  void *rewind();
+  // rewind the obstack iterator, and return the address of the first
+  // allocated block. return 0 if there are no allocated blocks.
+
+  void *next (int num_bytes);
+  // return the address of the next allocated block. 'num_bytes' is the size
+  // of the previous block. this returns null if there are no more arenas.
+  // the sequence of 'num_bytes' parameters passed to next() during a
+  // traversal of the list must exactly match the parameters passed to alloc().
+};
+
+
+#endif