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
9 #include "include/overridable_function.h"
10 #include <__assert>
11 #include <__memory/aligned_alloc.h>
12 #include <cstddef>
13 #include <cstdlib>
14 #include <new>
15
16 #if !defined(__GLIBCXX__) && !defined(_LIBCPP_ABI_VCRUNTIME)
17
18 // The code below is copied as-is into libc++abi's libcxxabi/src/stdlib_new_delete.cpp
19 // file. The version in this file is the canonical one.
20
__throw_bad_alloc_shim()21 inline void __throw_bad_alloc_shim() { std::__throw_bad_alloc(); }
22
23 # define _LIBCPP_ASSERT_SHIM(expr, str) _LIBCPP_ASSERT(expr, str)
24
25 // ------------------ BEGIN COPY ------------------
26 // Implement all new and delete operators as weak definitions
27 // in this shared library, so that they can be overridden by programs
28 // that define non-weak copies of the functions.
29
operator_new_impl(std::size_t size)30 static void* operator_new_impl(std::size_t size) {
31 if (size == 0)
32 size = 1;
33 void* p;
34 while ((p = std::malloc(size)) == nullptr) {
35 // If malloc fails and there is a new_handler,
36 // call it to try free up memory.
37 std::new_handler nh = std::get_new_handler();
38 if (nh)
39 nh();
40 else
41 break;
42 }
43 return p;
44 }
45
46 _LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new, (std::size_t size)) _THROW_BAD_ALLOC {
47 void* p = operator_new_impl(size);
48 if (p == nullptr)
49 __throw_bad_alloc_shim();
50 return p;
51 }
52
operator new(size_t size,const std::nothrow_t &)53 _LIBCPP_WEAK void* operator new(size_t size, const std::nothrow_t&) noexcept {
54 # if !_LIBCPP_HAS_EXCEPTIONS
55 # if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
56 _LIBCPP_ASSERT_SHIM(
57 (!std::__is_function_overridden < void*(std::size_t), &operator new>()),
58 "libc++ was configured with exceptions disabled and `operator new(size_t)` has been overridden, "
59 "but `operator new(size_t, nothrow_t)` has not been overridden. This is problematic because "
60 "`operator new(size_t, nothrow_t)` must call `operator new(size_t)`, which will terminate in case "
61 "it fails to allocate, making it impossible for `operator new(size_t, nothrow_t)` to fulfill its "
62 "contract (since it should return nullptr upon failure). Please make sure you override "
63 "`operator new(size_t, nothrow_t)` as well.");
64 # endif
65
66 return operator_new_impl(size);
67 # else
68 void* p = nullptr;
69 try {
70 p = ::operator new(size);
71 } catch (...) {
72 }
73 return p;
74 # endif
75 }
76
77 _LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new[], (size_t size)) _THROW_BAD_ALLOC { return ::operator new(size); }
78
operator new[](size_t size,const std::nothrow_t &)79 _LIBCPP_WEAK void* operator new[](size_t size, const std::nothrow_t&) noexcept {
80 # if !_LIBCPP_HAS_EXCEPTIONS
81 # if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
82 _LIBCPP_ASSERT_SHIM(
83 (!std::__is_function_overridden < void*(std::size_t), &operator new[]>()),
84 "libc++ was configured with exceptions disabled and `operator new[](size_t)` has been overridden, "
85 "but `operator new[](size_t, nothrow_t)` has not been overridden. This is problematic because "
86 "`operator new[](size_t, nothrow_t)` must call `operator new[](size_t)`, which will terminate in case "
87 "it fails to allocate, making it impossible for `operator new[](size_t, nothrow_t)` to fulfill its "
88 "contract (since it should return nullptr upon failure). Please make sure you override "
89 "`operator new[](size_t, nothrow_t)` as well.");
90 # endif
91
92 return operator_new_impl(size);
93 # else
94 void* p = nullptr;
95 try {
96 p = ::operator new[](size);
97 } catch (...) {
98 }
99 return p;
100 # endif
101 }
102
operator delete(void * ptr)103 _LIBCPP_WEAK void operator delete(void* ptr) noexcept { std::free(ptr); }
104
operator delete(void * ptr,const std::nothrow_t &)105 _LIBCPP_WEAK void operator delete(void* ptr, const std::nothrow_t&) noexcept { ::operator delete(ptr); }
106
operator delete(void * ptr,size_t)107 _LIBCPP_WEAK void operator delete(void* ptr, size_t) noexcept { ::operator delete(ptr); }
108
operator delete[](void * ptr)109 _LIBCPP_WEAK void operator delete[](void* ptr) noexcept { ::operator delete(ptr); }
110
operator delete[](void * ptr,const std::nothrow_t &)111 _LIBCPP_WEAK void operator delete[](void* ptr, const std::nothrow_t&) noexcept { ::operator delete[](ptr); }
112
operator delete[](void * ptr,size_t)113 _LIBCPP_WEAK void operator delete[](void* ptr, size_t) noexcept { ::operator delete[](ptr); }
114
115 # if _LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION
116
operator_new_aligned_impl(std::size_t size,std::align_val_t alignment)117 static void* operator_new_aligned_impl(std::size_t size, std::align_val_t alignment) {
118 if (size == 0)
119 size = 1;
120 if (static_cast<size_t>(alignment) < sizeof(void*))
121 alignment = std::align_val_t(sizeof(void*));
122
123 // Try allocating memory. If allocation fails and there is a new_handler,
124 // call it to try free up memory, and try again until it succeeds, or until
125 // the new_handler decides to terminate.
126 void* p;
127 while ((p = std::__libcpp_aligned_alloc(static_cast<std::size_t>(alignment), size)) == nullptr) {
128 std::new_handler nh = std::get_new_handler();
129 if (nh)
130 nh();
131 else
132 break;
133 }
134 return p;
135 }
136
137 _LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new, (std::size_t size, std::align_val_t alignment)) _THROW_BAD_ALLOC {
138 void* p = operator_new_aligned_impl(size, alignment);
139 if (p == nullptr)
140 __throw_bad_alloc_shim();
141 return p;
142 }
143
operator new(size_t size,std::align_val_t alignment,const std::nothrow_t &)144 _LIBCPP_WEAK void* operator new(size_t size, std::align_val_t alignment, const std::nothrow_t&) noexcept {
145 # if !_LIBCPP_HAS_EXCEPTIONS
146 # if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
147 _LIBCPP_ASSERT_SHIM(
148 (!std::__is_function_overridden < void*(std::size_t, std::align_val_t), &operator new>()),
149 "libc++ was configured with exceptions disabled and `operator new(size_t, align_val_t)` has been overridden, "
150 "but `operator new(size_t, align_val_t, nothrow_t)` has not been overridden. This is problematic because "
151 "`operator new(size_t, align_val_t, nothrow_t)` must call `operator new(size_t, align_val_t)`, which will "
152 "terminate in case it fails to allocate, making it impossible for `operator new(size_t, align_val_t, nothrow_t)` "
153 "to fulfill its contract (since it should return nullptr upon failure). Please make sure you override "
154 "`operator new(size_t, align_val_t, nothrow_t)` as well.");
155 # endif
156
157 return operator_new_aligned_impl(size, alignment);
158 # else
159 void* p = nullptr;
160 try {
161 p = ::operator new(size, alignment);
162 } catch (...) {
163 }
164 return p;
165 # endif
166 }
167
168 _LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new[], (size_t size, std::align_val_t alignment)) _THROW_BAD_ALLOC {
169 return ::operator new(size, alignment);
170 }
171
operator new[](size_t size,std::align_val_t alignment,const std::nothrow_t &)172 _LIBCPP_WEAK void* operator new[](size_t size, std::align_val_t alignment, const std::nothrow_t&) noexcept {
173 # if !_LIBCPP_HAS_EXCEPTIONS
174 # if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
175 _LIBCPP_ASSERT_SHIM(
176 (!std::__is_function_overridden < void*(std::size_t, std::align_val_t), &operator new[]>()),
177 "libc++ was configured with exceptions disabled and `operator new[](size_t, align_val_t)` has been overridden, "
178 "but `operator new[](size_t, align_val_t, nothrow_t)` has not been overridden. This is problematic because "
179 "`operator new[](size_t, align_val_t, nothrow_t)` must call `operator new[](size_t, align_val_t)`, which will "
180 "terminate in case it fails to allocate, making it impossible for `operator new[](size_t, align_val_t, "
181 "nothrow_t)` to fulfill its contract (since it should return nullptr upon failure). Please make sure you "
182 "override `operator new[](size_t, align_val_t, nothrow_t)` as well.");
183 # endif
184
185 return operator_new_aligned_impl(size, alignment);
186 # else
187 void* p = nullptr;
188 try {
189 p = ::operator new[](size, alignment);
190 } catch (...) {
191 }
192 return p;
193 # endif
194 }
195
operator delete(void * ptr,std::align_val_t)196 _LIBCPP_WEAK void operator delete(void* ptr, std::align_val_t) noexcept { std::__libcpp_aligned_free(ptr); }
197
operator delete(void * ptr,std::align_val_t alignment,const std::nothrow_t &)198 _LIBCPP_WEAK void operator delete(void* ptr, std::align_val_t alignment, const std::nothrow_t&) noexcept {
199 ::operator delete(ptr, alignment);
200 }
201
operator delete(void * ptr,size_t,std::align_val_t alignment)202 _LIBCPP_WEAK void operator delete(void* ptr, size_t, std::align_val_t alignment) noexcept {
203 ::operator delete(ptr, alignment);
204 }
205
operator delete[](void * ptr,std::align_val_t alignment)206 _LIBCPP_WEAK void operator delete[](void* ptr, std::align_val_t alignment) noexcept {
207 ::operator delete(ptr, alignment);
208 }
209
operator delete[](void * ptr,std::align_val_t alignment,const std::nothrow_t &)210 _LIBCPP_WEAK void operator delete[](void* ptr, std::align_val_t alignment, const std::nothrow_t&) noexcept {
211 ::operator delete[](ptr, alignment);
212 }
213
operator delete[](void * ptr,size_t,std::align_val_t alignment)214 _LIBCPP_WEAK void operator delete[](void* ptr, size_t, std::align_val_t alignment) noexcept {
215 ::operator delete[](ptr, alignment);
216 }
217
218 # endif // _LIBCPP_HAS_LIBRARY_ALIGNED_ALLOCATION
219 // ------------------ END COPY ------------------
220
221 #endif // !__GLIBCXX__ && !_LIBCPP_ABI_VCRUNTIME
222