src/memory.c

   1 /*
   2  * Copyright (C) Prikol Software 1996-1997
   3  * Copyright (C) Aleksey Volynskov 1996-1997
   4  * Copyright (C) fgsfds 2019
   5  *
   6  * This file is part of the Doom2D PSX project.
   7  *
   8  * Doom2D PSX is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * Doom2D PSX is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/> or
  19  * write to the Free Software Foundation, Inc.,
  20  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  21  */
  22
  23 #include "glob.h"
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <malloc.h>
  27 #include <string.h>
  28 #include <libapi.h>
  29 #include "error.h"
  30 #include "files.h"
  31 #include "memory.h"
  32
  33 dword dpmi_memavl(void);
  34
  35 extern int d_start, d_end;
  36
  37 extern mwad_t wad[];
  38
  39 static byte m_active = FALSE;
  40
  41 static void * resp[MAX_WAD];
  42 static short resl[MAX_WAD];
  43
  44 void M_startup(void *heapbase, unsigned long heapsize) {
  45   if (m_active)
  46     return;
  47
  48   logo("M_startup(): memory init: %u kb heap at %p\n", heapsize >> 10, heapbase);
  49
  50   InitHeap3((void*)heapbase, heapsize);
  51
  52   memset(resp, 0, sizeof(resp));
  53   memset(resl, 0, sizeof(resl));
  54   //  logo("  свободно DPMI-памяти: %uK\n",dpmi_memavl()>>10);
  55   m_active = TRUE;
  56 }
  57
  58 void M_shutdown(void) {
  59   if (!m_active)
  60     return;
  61
  62   m_active = FALSE;
  63 }
  64
  65 static void allocres(int h) {
  66   int *p;
  67   if (!(p = malloc3(wad[h].l + 4)))
  68     ERR_fatal("M_lock: malloc3 failed");
  69   *p = h;
  70   ++p;
  71   resp[h] = p;
  72   F_loadres(h, p, 0, wad[h].l);
  73 }
  74
  75 void * M_lock(int h) {
  76   if ((h == -1) || (h == 0xFFFF))
  77     return NULL;
  78
  79   h &= -1 - 0x8000;
  80   if (h >= MAX_WAD)
  81     ERR_fatal("M_lock: funny resource number");
  82   if (!resl[h]) {
  83     if (!resp[h])
  84       allocres(h);
  85   }
  86   ++resl[h];
  87   return resp[h];
  88 }
  89
  90 void M_unlock(void * p) {
  91   int h;
  92
  93   if (!p)
  94     return;
  95
  96   h = ((int *) p)[-1];
  97   if (h >= MAX_WAD)
  98     ERR_fatal("M_unlock: funny resource number");
  99   if (!resl[h])
 100     return;
 101
 102   --resl[h];
 103
 104   if (!resl[h]) {
 105     // printf("M_unlock(): freeing resource %x\n", h);
 106     free3((int*)p - 1);
 107     resp[h] = NULL;
 108   }
 109 }