external/bsd/libc++/dist/libcxxrt/src/memory.cc

   1 /*
   2  * Copyright 2010-2011 PathScale, Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are met:
   6  *
   7  * 1. Redistributions of source code must retain the above copyright notice,
   8  *    this list of conditions and the following disclaimer.
   9  *
  10  * 2. Redistributions in binary form must reproduce the above copyright notice,
  11  *    this list of conditions and the following disclaimer in the documentation
  12  *    and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
  15  * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  16  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  21  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  22  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  23  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  24  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 /**
  28  * memory.cc - Contains stub definition of C++ new/delete operators.
  29  *
  30  * These definitions are intended to be used for testing and are weak symbols
  31  * to allow them to be replaced by definitions from a STL implementation.
  32  * These versions simply wrap malloc() and free(), they do not provide a
  33  * C++-specific allocator.
  34  */
  35
  36 #include <stddef.h>
  37 #include <stdlib.h>
  38 #include "stdexcept.h"
  39 #include "atomic.h"
  40
  41
  42 namespace std
  43 {
  44         struct nothrow_t {};
  45 }
  46
  47
  48 /// The type of the function called when allocation fails.
  49 typedef void (*new_handler)();
  50 /**
  51  * The function to call when allocation fails.  By default, there is no
  52  * handler and a bad allocation exception is thrown if an allocation fails.
  53  */
  54 static new_handler new_handl;
  55
  56 namespace std
  57 {
  58         /**
  59          * Sets a function to be called when there is a failure in new.
  60          */
  61         __attribute__((weak))
  62         new_handler set_new_handler(new_handler handler)
  63         {
  64                 return ATOMIC_SWAP(&new_handl, handler);
  65         }
  66         __attribute__((weak))
  67         new_handler get_new_handler(void)
  68         {
  69                 return ATOMIC_LOAD(&new_handl);
  70         }
  71 }
  72
  73
  74 __attribute__((weak))
  75 void* operator new(size_t size)
  76 {
  77         if (0 == size)
  78         {
  79                 size = 1;
  80         }
  81         void * mem = malloc(size);
  82         while (0 == mem)
  83         {
  84                 new_handler h = std::get_new_handler();
  85                 if (0 != h)
  86                 {
  87                         h();
  88                 }
  89                 else
  90                 {
  91                         throw std::bad_alloc();
  92                 }
  93                 mem = malloc(size);
  94         }
  95
  96         return mem;
  97 }
  98
  99 __attribute__((weak))
 100 void* operator new(size_t size, const std::nothrow_t &) throw()
 101 {
 102         try {
 103                 return :: operator new(size);
 104         } catch (...) {
 105                 // nothrow operator new should return NULL in case of
 106                 // std::bad_alloc exception in new handler
 107                 return NULL;
 108         }
 109 }
 110
 111
 112 __attribute__((weak))
 113 void operator delete(void * ptr)
 114 #if __cplusplus < 201000L
 115 throw()
 116 #endif
 117 {
 118         free(ptr);
 119 }
 120
 121
 122 __attribute__((weak))
 123 void * operator new[](size_t size)
 124 #if __cplusplus < 201000L
 125 throw(std::bad_alloc)
 126 #endif
 127 {
 128         return ::operator new(size);
 129 }
 130
 131
 132 __attribute__((weak))
 133 void * operator new[](size_t size, const std::nothrow_t &) throw()
 134 {
 135         try {
 136                 return ::operator new[](size);
 137         } catch (...) {
 138                 // nothrow operator new should return NULL in case of
 139                 // std::bad_alloc exception in new handler
 140                 return NULL;
 141         }
 142 }
 143
 144
 145 __attribute__((weak))
 146 void operator delete[](void * ptr)
 147 #if __cplusplus < 201000L
 148 throw()
 149 #endif
 150 {
 151         ::operator delete(ptr);
 152 }
 153
 154