src/video/pool.c

   1 /*
   2  * libneuro, a light weight abstraction of high or lower libraries
   3  * and toolkit for applications.
   4  * Copyright (C) 2005-2006  Nicholas Niro, Robert Lemay
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License.
  10  *
  11  * This library 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 GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 /* pool.c
  22  * Module : Pool
  23  *
  24  * memory management system, not really performant though, its actually better
  25  * to free and reallocate then trying not to free...
  26  */
  27
  28 /*-------------------- Extern Headers Including --------------------*/
  29
  30
  31 /*-------------------- Local Headers Including ---------------------*/
  32
  33 /*-------------------- Main Module Header --------------------------*/
  34 #include "pool.h"
  35
  36
  37 /*--------------------      Other       ----------------------------*/
  38
  39 enum POOL_TYPES
  40 {
  41         POOL_AVAILABLE = 0, /* an available spot */
  42         POOL_RAWENGINE = 1, /* RAW_ENGINE */
  43         POOL_QUEUE, /* INSTRUCTION_ENGINE */
  44         /*POOL_PIXELS,*/ /* PIXEL_ENGINE */
  45
  46         POOL_LAST
  47 };
  48
  49 /* this is the memory pool structure
  50  * made to keep track of unused memory
  51  * so it can be used again if necessary.
  52  *
  53  * ** note **
  54  * this test (although working well technically) was
  55  * an awful performance failure so it was dropped.
  56  *
  57  * the code was kept for future reference,
  58  * see the macro use_memory_pool to toggle the use
  59  * of this feature.
  60  */
  61 typedef struct STRUCT_POOL
  62 {
  63         u8 type;
  64         void *data;
  65 }STRUCT_POOL;
  66
  67 /*-------------------- Global Variables ----------------------------*/
  68
  69 /*-------------------- Static Variables ----------------------------*/
  70 /* pool used to reuse allocated memory */
  71 static EBUF *_pool;
  72
  73
  74 /*-------------------- Static Prototypes ---------------------------*/
  75
  76
  77
  78 /*-------------------- Static Functions ----------------------------*/
  79
  80 /*-------------------- Global Functions ----------------------------*/
  81
  82 /* function to put a new element in the pool */
  83 void
  84 Pool_PushData(u8 type, void *data)
  85 {
  86         STRUCT_POOL *tmp;
  87         u32 total = 0;
  88
  89         /* Debug_Val(0, "Pushed a struct to be in the pool\n"); */
  90         if (!Neuro_EBufIsEmpty(_pool))
  91         {
  92                 total = Neuro_GiveEBufCount(_pool) + 1;
  93
  94                 /* loop the buffer to attempt to put the data
  95                  * into an available spot
  96                  */
  97                 while (total-- > 0)
  98                 {
  99                         tmp = Neuro_GiveEBuf(_pool, total);
 100
 101                         if (tmp->type == POOL_AVAILABLE)
 102                         {
 103                                 /* Debug_Val(0, "putting data into an available slot\n"); */
 104                                 tmp->type = type;
 105                                 tmp->data = data;
 106
 107                                 return;
 108                         }
 109                 }
 110         }
 111
 112         /* Debug_Val(0, "no more available slots, we need to allocate a new one\n"); */
 113
 114         /* if we are here, it means there was no available
 115          * spot found. We will have to create a new one.
 116          * and put the data in it.
 117          */
 118         Neuro_AllocEBuf(_pool, sizeof(STRUCT_POOL*), sizeof(STRUCT_POOL));
 119
 120         tmp = Neuro_GiveCurEBuf(_pool);
 121
 122         tmp->type = type;
 123         tmp->data = data;
 124 }
 125
 126
 127 /* returns a pointer corresponding to the type or
 128  * NULL if none found
 129  */
 130 void *
 131 Pool_PullData(u8 type)
 132 {
 133         STRUCT_POOL *tmp;
 134         u32 total = 0;
 135         void *ret = NULL;
 136
 137         if (Neuro_EBufIsEmpty(_pool))
 138                 return NULL;
 139
 140         total = Neuro_GiveEBufCount(_pool) + 1;
 141
 142         while (total-- > 0)
 143         {
 144                 tmp = Neuro_GiveEBuf(_pool, total);
 145
 146                 if (tmp->type == type)
 147                 {
 148                         tmp->type = POOL_AVAILABLE;
 149                         ret = tmp->data;
 150                         tmp->data = NULL;
 151
 152                         return ret;
 153                 }
 154         }
 155
 156         return NULL;
 157 }
 158 /*-------------------- Poll ----------------------------------------*/
 159
 160 void
 161 Pool_Poll()
 162 {
 163
 164 }
 165
 166 /*-------------------- Constructor Destructor ----------------------*/
 167
 168 int
 169 Pool_Init()
 170 {
 171         Neuro_CreateEBuf(&_pool);
 172         return 0;
 173 }
 174
 175 void
 176 Pool_Clean()
 177 {
 178         Neuro_CleanEBuf(&_pool);
 179 }