icuSources/common/cmemory.cpp

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 ******************************************************************************
   5 *
   6 *   Copyright (C) 2002-2015, International Business Machines
   7 *   Corporation and others.  All Rights Reserved.
   8 *
   9 ******************************************************************************
  10 *
  11 * File cmemory.c      ICU Heap allocation.
  12 *                     All ICU heap allocation, both for C and C++ new of ICU
  13 *                     class types, comes through these functions.
  14 *
  15 *                     If you have a need to replace ICU allocation, this is the
  16 *                     place to do it.
  17 *
  18 *                     Note that uprv_malloc(0) returns a non-NULL pointer, and
  19 *                     that a subsequent free of that pointer value is a NOP.
  20 *
  21 ******************************************************************************
  22 */
  23 #include "unicode/uclean.h"
  24 #include "cmemory.h"
  25 #include "putilimp.h"
  26 #include "uassert.h"
  27 #include <stdlib.h>
  28
  29 /* uprv_malloc(0) returns a pointer to this read-only data. */
  30 static const int32_t zeroMem[] = {0, 0, 0, 0, 0, 0};
  31
  32 /* Function Pointers for user-supplied heap functions  */
  33 static const void     *pContext;
  34 static UMemAllocFn    *pAlloc;
  35 static UMemReallocFn  *pRealloc;
  36 static UMemFreeFn     *pFree;
  37
  38 #if U_DEBUG && defined(UPRV_MALLOC_COUNT)
  39 #include <stdio.h>
  40 static int n=0;
  41 static long b=0;
  42 #endif
  43
  44 #if U_DEBUG
  45
  46 static char gValidMemorySink = 0;
  47
  48 U_CAPI void uprv_checkValidMemory(const void *p, size_t n) {
  49     /*
  50      * Access the memory to ensure that it's all valid.
  51      * Load and save a computed value to try to ensure that the compiler
  52      * does not throw away the whole loop.
  53      * A thread analyzer might complain about un-mutexed access to gValidMemorySink
  54      * which is true but harmless because no one ever uses the value in gValidMemorySink.
  55      */
  56     const char *s = (const char *)p;
  57     char c = gValidMemorySink;
  58     size_t i;
  59     U_ASSERT(p != NULL);
  60     for(i = 0; i < n; ++i) {
  61         c ^= s[i];
  62     }
  63     gValidMemorySink = c;
  64 }
  65
  66 #endif  /* U_DEBUG */
  67
  68 U_CAPI void * U_EXPORT2
  69 uprv_malloc(size_t s) {
  70 #if U_DEBUG && defined(UPRV_MALLOC_COUNT)
  71 #if 1
  72   putchar('>');
  73   fflush(stdout);
  74 #else
  75   fprintf(stderr,"MALLOC\t#%d\t%ul bytes\t%ul total\n", ++n,s,(b+=s)); fflush(stderr);
  76 #endif
  77 #endif
  78     if (s > 0) {
  79         if (pAlloc) {
  80             return (*pAlloc)(pContext, s);
  81         } else {
  82             return uprv_default_malloc(s);
  83         }
  84     } else {
  85         return (void *)zeroMem;
  86     }
  87 }
  88
  89 U_CAPI void * U_EXPORT2
  90 uprv_realloc(void * buffer, size_t size) {
  91 #if U_DEBUG && defined(UPRV_MALLOC_COUNT)
  92   putchar('~');
  93   fflush(stdout);
  94 #endif
  95     if (buffer == zeroMem) {
  96         return uprv_malloc(size);
  97     } else if (size == 0) {
  98         if (pFree) {
  99             (*pFree)(pContext, buffer);
 100         } else {
 101             uprv_default_free(buffer);
 102         }
 103         return (void *)zeroMem;
 104     } else {
 105         if (pRealloc) {
 106             return (*pRealloc)(pContext, buffer, size);
 107         } else {
 108             return uprv_default_realloc(buffer, size);
 109         }
 110     }
 111 }
 112
 113 U_CAPI void U_EXPORT2
 114 uprv_free(void *buffer) {
 115 #if U_DEBUG && defined(UPRV_MALLOC_COUNT)
 116   putchar('<');
 117   fflush(stdout);
 118 #endif
 119     if (buffer != zeroMem) {
 120         if (pFree) {
 121             (*pFree)(pContext, buffer);
 122         } else {
 123             uprv_default_free(buffer);
 124         }
 125     }
 126 }
 127
 128 U_CAPI void * U_EXPORT2
 129 uprv_calloc(size_t num, size_t size) {
 130     void *mem = NULL;
 131     size *= num;
 132     mem = uprv_malloc(size);
 133     if (mem) {
 134         uprv_memset(mem, 0, size);
 135     }
 136     return mem;
 137 }
 138
 139 U_CAPI void U_EXPORT2
 140 u_setMemoryFunctions(const void *context, UMemAllocFn *a, UMemReallocFn *r, UMemFreeFn *f,  UErrorCode *status)
 141 {
 142     if (U_FAILURE(*status)) {
 143         return;
 144     }
 145     if (a==NULL || r==NULL || f==NULL) {
 146         *status = U_ILLEGAL_ARGUMENT_ERROR;
 147         return;
 148     }
 149     pContext  = context;
 150     pAlloc    = a;
 151     pRealloc  = r;
 152     pFree     = f;
 153 }
 154
 155
 156 U_CFUNC UBool cmemory_cleanup(void) {
 157     pContext   = NULL;
 158     pAlloc     = NULL;
 159     pRealloc   = NULL;
 160     pFree      = NULL;
 161     return TRUE;
 162 }