workbench/devs/diskimage/z_library/malloc.c

   1 /* Copyright 2007-2012 Fredrik Wikstrom. All rights reserved.
   2 **
   3 ** Redistribution and use in source and binary forms, with or without
   4 ** modification, are permitted provided that the following conditions
   5 ** are met:
   6 **
   7 ** 1. Redistributions of source code must retain the above copyright
   8 **    notice, this list of conditions and the following disclaimer.
   9 **
  10 ** 2. Redistributions in binary form must reproduce the above copyright
  11 **    notice, this list of conditions and the following disclaimer in the
  12 **    documentation and/or other materials provided with the distribution.
  13 **
  14 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
  15 ** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17 ** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  18 ** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  19 ** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  20 ** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  21 ** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  22 ** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  23 ** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  24 ** POSSIBILITY OF SUCH DAMAGE.
  25 */
  26
  27 #include <proto/exec.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include "support.h"
  31
  32 #define BASE_PTR(ptr) ((void *)((size_t *)ptr - 1))
  33 #define ALLOC_SIZE(ptr) (*((size_t *)ptr - 1))
  34
  35 static struct SignalSemaphore *LibPoolSemaphore;
  36 static APTR LibPool;
  37
  38 int malloc_init(void) {
  39         LibPoolSemaphore = CreateSemaphore();
  40         if (LibPoolSemaphore) {
  41                 LibPool = CreatePool(MEMF_ANY, 4096, 1024);
  42                 if (LibPool) {
  43                         return TRUE;
  44                 }
  45                 DeleteSemaphore(LibPoolSemaphore);
  46         }
  47         return FALSE;
  48 }
  49
  50 void malloc_exit(void) {
  51         DeletePool(LibPool);
  52         DeleteSemaphore(LibPoolSemaphore);
  53 }
  54
  55 void *malloc(size_t size) {
  56         size_t *ptr;
  57         ObtainSemaphore(LibPoolSemaphore);
  58         ptr = AllocPooled(LibPool, sizeof(size_t) + size);
  59         ReleaseSemaphore(LibPoolSemaphore);
  60         if (ptr) {
  61                 *ptr++ = size;
  62         }
  63         return ptr;
  64 }
  65
  66 void free(void *ptr) {
  67         if (ptr) {
  68                 ObtainSemaphore(LibPoolSemaphore);
  69                 FreePooled(LibPool, BASE_PTR(ptr), sizeof(size_t) + ALLOC_SIZE(ptr));
  70                 ReleaseSemaphore(LibPoolSemaphore);
  71         }
  72 }