release/src/router/mysql/storage/ndb/src/kernel/vm/DynArr256.hpp

   1 /* Copyright (c) 2003, 2006, 2007 MySQL AB
   2
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; version 2 of the License.
   6
   7    This program is distributed in the hope that it will be useful,
   8    but WITHOUT ANY WARRANTY; without even the implied warranty of
   9    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10    GNU General Public License for more details.
  11
  12    You should have received a copy of the GNU General Public License
  13    along with this program; if not, write to the Free Software
  14    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA */
  15
  16 #ifndef DYNARR256_HPP
  17 #define DYNARR256_HPP
  18
  19 #include "Pool.hpp"
  20
  21 class DynArr256;
  22 struct DA256Page;
  23
  24 class DynArr256Pool
  25 {
  26   friend class DynArr256;
  27 public:
  28   DynArr256Pool();
  29
  30   void init(Uint32 type_id, const Pool_context& pc);
  31
  32 protected:
  33   Uint32 m_type_id;
  34   Uint32 m_first_free;
  35   Pool_context m_ctx;
  36   struct DA256Page* m_memroot;
  37
  38 private:
  39   Uint32 seize();
  40   void release(Uint32);
  41 };
  42
  43 class DynArr256
  44 {
  45 public:
  46   struct Head
  47   {
  48     Head() { m_ptr_i = RNIL; m_sz = 0;}
  49
  50     Uint32 m_ptr_i;
  51     Uint32 m_sz;
  52
  53     bool isEmpty() const { return m_sz == 0;}
  54   };
  55
  56   DynArr256(DynArr256Pool & pool, Head& head) :
  57     m_head(head), m_pool(pool){}
  58
  59   Uint32* set(Uint32 pos);
  60   Uint32* get(Uint32 pos) const ;
  61
  62   struct ReleaseIterator
  63   {
  64     Uint32 m_sz;
  65     Uint32 m_pos;
  66     Uint32 m_ptr_i[5];
  67   };
  68
  69   void init(ReleaseIterator&);
  70   /**
  71    * return 0 - done
  72    *        1 - data (in retptr)
  73    *        2 - nodata
  74    */
  75   Uint32 release(ReleaseIterator&, Uint32* retptr);
  76 protected:
  77   Head & m_head;
  78   DynArr256Pool & m_pool;
  79
  80   bool expand(Uint32 pos);
  81   void handle_invalid_ptr(Uint32 pos, Uint32 ptrI, Uint32 p0);
  82 };
  83
  84 #endif