include/lang/AdvancingAllocPool.h

   1 /*
   2         SuperCollider real time audio synthesis system
   3     Copyright (c) 2002 James McCartney. All rights reserved.
   4         http://www.audiosynth.com
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  19 */
  20 /*
  21
  22 AdvancingAllocPool implements a simple advancing pointer allocation scheme.
  23 There is no Free(). All objects in the pool are freed at once with FreeAll().
  24 Thus it is very fast.
  25
  26 */
  27
  28 #ifndef _AdvancingAllocPool_
  29 #define _AdvancingAllocPool_
  30
  31 #include <stdexcept>
  32 #include <stdlib.h>
  33
  34 class AllocPool;
  35
  36 struct AdvancingAllocPoolChunk;
  37
  38 typedef int int32;
  39
  40 inline void FailNil(void *ptr) {
  41         if (!ptr) throw std::runtime_error("alloc failed");
  42 }
  43
  44 struct AdvancingAllocPoolChunkHdr {
  45         AdvancingAllocPoolChunk *mNext;
  46         size_t mSize;
  47         int32 mPad1, mPad2;
  48 };
  49
  50 struct AdvancingAllocPoolChunk {
  51         AdvancingAllocPoolChunk *mNext;
  52         size_t mSize;
  53         int32 mPad1, mPad2;
  54         char mSpace[16];
  55 };
  56
  57 class AdvancingAllocPool
  58 {
  59 public:
  60         AdvancingAllocPool();
  61         ~AdvancingAllocPool() { FreeAll(); }
  62
  63         void Init(AllocPool *inAllocPool, size_t initSize, size_t growSize, size_t tooBigSize);
  64
  65         void *Alloc(size_t inBytes);
  66         void FreeAll();
  67
  68         bool SanityCheck();
  69
  70 private:
  71         void AddChunk(size_t inSize);
  72
  73         AllocPool* mAllocPool;
  74         size_t mInitSize;
  75         size_t mGrowSize;
  76         size_t mCurSize;
  77         size_t mTooBig;
  78         AdvancingAllocPoolChunk *mChunks;
  79         AdvancingAllocPoolChunk *mFatties;
  80 };
  81
  82 #endif