icuSources/common/cmemory.c

   1 /*
   2 ******************************************************************************
   3 *
   4 *   Copyright (C) 2002, International Business Machines
   5 *   Corporation and others.  All Rights Reserved.
   6 *
   7 ******************************************************************************
   8 *
   9 * File cmemory.c      ICU Heap allocation.
  10 *                     All ICU heap allocation, both for C and C++ new of ICU
  11 *                     class types, comes through these functions.
  12 *
  13 *                     If you have a need to replace ICU allocation, this is the
  14 *                     place to do it.
  15 *
  16 *                     Note that uprv_malloc(0) returns a non-NULL pointer, and
  17 *                     that a subsequent free of that pointer value is a NOP.
  18 *
  19 ******************************************************************************
  20 */
  21 #include "cmemory.h"
  22
  23 /* uprv_malloc(0) returns a pointer to this read-only data. */
  24 static const int32_t zeroMem[] = {0, 0, 0, 0, 0, 0};
  25
  26 U_CAPI void * U_EXPORT2
  27 uprv_malloc(size_t s) {
  28     if (s > 0) {
  29         return malloc(s);
  30     } else {
  31         return (void *)zeroMem;
  32     }
  33 }
  34
  35 U_CAPI void * U_EXPORT2
  36 uprv_realloc(void * buffer, size_t size) {
  37     if (buffer == zeroMem) {
  38         return uprv_malloc(size);
  39     } else if (size == 0) {
  40         free(buffer);
  41         return (void *)zeroMem;
  42     } else {
  43         return realloc(buffer, size);
  44     }
  45 }
  46
  47 U_CAPI void U_EXPORT2
  48 uprv_free(void *buffer) {
  49     if (buffer != zeroMem) {
  50         free(buffer);
  51     }
  52 }
  53