libcxxabi/src/stdlib_new_delete.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //
   8 // This file implements the new and delete operators.
   9 //===----------------------------------------------------------------------===//
  10
  11 #include "__cxxabi_config.h"
  12 #include <new>
  13 #include <cstdlib>
  14
  15 #if !defined(_THROW_BAD_ALLOC) || !defined(_LIBCXXABI_WEAK)
  16 #error The _THROW_BAD_ALLOC and _LIBCXXABI_WEAK libc++ macros must \
  17        already be defined by libc++.
  18 #endif
  19 // Implement all new and delete operators as weak definitions
  20 // in this shared library, so that they can be overridden by programs
  21 // that define non-weak copies of the functions.
  22
  23 _LIBCXXABI_WEAK
  24 void *
  25 operator new(std::size_t size) _THROW_BAD_ALLOC
  26 {
  27     if (size == 0)
  28         size = 1;
  29     void* p;
  30     while ((p = ::malloc(size)) == nullptr)
  31     {
  32         // If malloc fails and there is a new_handler,
  33         // call it to try free up memory.
  34         std::new_handler nh = std::get_new_handler();
  35         if (nh)
  36             nh();
  37         else
  38 #ifndef _LIBCXXABI_NO_EXCEPTIONS
  39             throw std::bad_alloc();
  40 #else
  41             break;
  42 #endif
  43     }
  44     return p;
  45 }
  46
  47 _LIBCXXABI_WEAK
  48 void*
  49 operator new(size_t size, const std::nothrow_t&) noexcept
  50 {
  51     void* p = nullptr;
  52 #ifndef _LIBCXXABI_NO_EXCEPTIONS
  53     try
  54     {
  55 #endif // _LIBCXXABI_NO_EXCEPTIONS
  56         p = ::operator new(size);
  57 #ifndef _LIBCXXABI_NO_EXCEPTIONS
  58     }
  59     catch (...)
  60     {
  61     }
  62 #endif // _LIBCXXABI_NO_EXCEPTIONS
  63     return p;
  64 }
  65
  66 _LIBCXXABI_WEAK
  67 void*
  68 operator new[](size_t size) _THROW_BAD_ALLOC
  69 {
  70     return ::operator new(size);
  71 }
  72
  73 _LIBCXXABI_WEAK
  74 void*
  75 operator new[](size_t size, const std::nothrow_t&) noexcept
  76 {
  77     void* p = nullptr;
  78 #ifndef _LIBCXXABI_NO_EXCEPTIONS
  79     try
  80     {
  81 #endif // _LIBCXXABI_NO_EXCEPTIONS
  82         p = ::operator new[](size);
  83 #ifndef _LIBCXXABI_NO_EXCEPTIONS
  84     }
  85     catch (...)
  86     {
  87     }
  88 #endif // _LIBCXXABI_NO_EXCEPTIONS
  89     return p;
  90 }
  91
  92 _LIBCXXABI_WEAK
  93 void
  94 operator delete(void* ptr) noexcept
  95 {
  96     ::free(ptr);
  97 }
  98
  99 _LIBCXXABI_WEAK
 100 void
 101 operator delete(void* ptr, const std::nothrow_t&) noexcept
 102 {
 103     ::operator delete(ptr);
 104 }
 105
 106 _LIBCXXABI_WEAK
 107 void
 108 operator delete(void* ptr, size_t) noexcept
 109 {
 110     ::operator delete(ptr);
 111 }
 112
 113 _LIBCXXABI_WEAK
 114 void
 115 operator delete[] (void* ptr) noexcept
 116 {
 117     ::operator delete(ptr);
 118 }
 119
 120 _LIBCXXABI_WEAK
 121 void
 122 operator delete[] (void* ptr, const std::nothrow_t&) noexcept
 123 {
 124     ::operator delete[](ptr);
 125 }
 126
 127 _LIBCXXABI_WEAK
 128 void
 129 operator delete[] (void* ptr, size_t) noexcept
 130 {
 131     ::operator delete[](ptr);
 132 }
 133
 134 #if !defined(_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION)
 135
 136 _LIBCXXABI_WEAK
 137 void *
 138 operator new(std::size_t size, std::align_val_t alignment) _THROW_BAD_ALLOC
 139 {
 140     if (size == 0)
 141         size = 1;
 142     if (static_cast<size_t>(alignment) < sizeof(void*))
 143       alignment = std::align_val_t(sizeof(void*));
 144
 145     // Try allocating memory. If allocation fails and there is a new_handler,
 146     // call it to try free up memory, and try again until it succeeds, or until
 147     // the new_handler decides to terminate.
 148     //
 149     // If allocation fails and there is no new_handler, we throw bad_alloc
 150     // (or return nullptr if exceptions are disabled).
 151     void* p;
 152     while ((p = std::__libcpp_aligned_alloc(static_cast<std::size_t>(alignment), size)) == nullptr)
 153     {
 154         std::new_handler nh = std::get_new_handler();
 155         if (nh)
 156             nh();
 157         else {
 158 #ifndef _LIBCXXABI_NO_EXCEPTIONS
 159             throw std::bad_alloc();
 160 #else
 161             break;
 162 #endif
 163         }
 164     }
 165     return p;
 166 }
 167
 168 _LIBCXXABI_WEAK
 169 void*
 170 operator new(size_t size, std::align_val_t alignment, const std::nothrow_t&) noexcept
 171 {
 172     void* p = nullptr;
 173 #ifndef _LIBCXXABI_NO_EXCEPTIONS
 174     try
 175     {
 176 #endif // _LIBCXXABI_NO_EXCEPTIONS
 177         p = ::operator new(size, alignment);
 178 #ifndef _LIBCXXABI_NO_EXCEPTIONS
 179     }
 180     catch (...)
 181     {
 182     }
 183 #endif // _LIBCXXABI_NO_EXCEPTIONS
 184     return p;
 185 }
 186
 187 _LIBCXXABI_WEAK
 188 void*
 189 operator new[](size_t size, std::align_val_t alignment) _THROW_BAD_ALLOC
 190 {
 191     return ::operator new(size, alignment);
 192 }
 193
 194 _LIBCXXABI_WEAK
 195 void*
 196 operator new[](size_t size, std::align_val_t alignment, const std::nothrow_t&) noexcept
 197 {
 198     void* p = nullptr;
 199 #ifndef _LIBCXXABI_NO_EXCEPTIONS
 200     try
 201     {
 202 #endif // _LIBCXXABI_NO_EXCEPTIONS
 203         p = ::operator new[](size, alignment);
 204 #ifndef _LIBCXXABI_NO_EXCEPTIONS
 205     }
 206     catch (...)
 207     {
 208     }
 209 #endif // _LIBCXXABI_NO_EXCEPTIONS
 210     return p;
 211 }
 212
 213 _LIBCXXABI_WEAK
 214 void
 215 operator delete(void* ptr, std::align_val_t) noexcept
 216 {
 217     std::__libcpp_aligned_free(ptr);
 218 }
 219
 220 _LIBCXXABI_WEAK
 221 void
 222 operator delete(void* ptr, std::align_val_t alignment, const std::nothrow_t&) noexcept
 223 {
 224     ::operator delete(ptr, alignment);
 225 }
 226
 227 _LIBCXXABI_WEAK
 228 void
 229 operator delete(void* ptr, size_t, std::align_val_t alignment) noexcept
 230 {
 231     ::operator delete(ptr, alignment);
 232 }
 233
 234 _LIBCXXABI_WEAK
 235 void
 236 operator delete[] (void* ptr, std::align_val_t alignment) noexcept
 237 {
 238     ::operator delete(ptr, alignment);
 239 }
 240
 241 _LIBCXXABI_WEAK
 242 void
 243 operator delete[] (void* ptr, std::align_val_t alignment, const std::nothrow_t&) noexcept
 244 {
 245     ::operator delete[](ptr, alignment);
 246 }
 247
 248 _LIBCXXABI_WEAK
 249 void
 250 operator delete[] (void* ptr, size_t, std::align_val_t alignment) noexcept
 251 {
 252     ::operator delete[](ptr, alignment);
 253 }
 254
 255 #endif // !_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION