xref: /llvm-project-15.0.7/libcxx/src/new.cpp (revision ff461fcf)
1 //===--------------------------- new.cpp ----------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include <stdlib.h>
11 
12 #include "new"
13 
14 #if __APPLE__
15     #include <cxxabi.h>
16 
17     #ifndef _LIBCPPABI_VERSION
18         // On Darwin, there are two STL shared libraries and a lower level ABI
19         // shared libray.  The global holding the current new handler is
20         // in the ABI library and named __cxa_new_handler.
21         #define __new_handler __cxxabiapple::__cxa_new_handler
22     #endif
23 #else  // __APPLE__
24     static std::new_handler __new_handler;
25 #endif
26 
27 #ifndef _LIBCPPABI_VERSION
28 
29 // Implement all new and delete operators as weak definitions
30 // in this shared library, so that they can be overriden by programs
31 // that define non-weak copies of the functions.
32 
33 __attribute__((__weak__, __visibility__("default")))
34 void *
35 operator new(std::size_t size)
36 #if !__has_feature(cxx_noexcept)
37     throw(std::bad_alloc)
38 #endif
39 {
40     if (size == 0)
41         size = 1;
42     void* p;
43     while ((p = ::malloc(size)) == 0)
44     {
45         // If malloc fails and there is a new_handler,
46         // call it to try free up memory.
47         std::new_handler nh = std::get_new_handler();
48         if (nh)
49             nh();
50         else
51 #ifndef _LIBCPP_NO_EXCEPTIONS
52             throw std::bad_alloc();
53 #else
54             break;
55 #endif
56     }
57     return p;
58 }
59 
60 __attribute__((__weak__, __visibility__("default")))
61 void*
62 operator new(size_t size, const std::nothrow_t&) _NOEXCEPT
63 {
64     void* p = 0;
65 #ifndef _LIBCPP_NO_EXCEPTIONS
66     try
67     {
68 #endif  // _LIBCPP_NO_EXCEPTIONS
69         p = ::operator new(size);
70 #ifndef _LIBCPP_NO_EXCEPTIONS
71     }
72     catch (...)
73     {
74     }
75 #endif  // _LIBCPP_NO_EXCEPTIONS
76     return p;
77 }
78 
79 __attribute__((__weak__, __visibility__("default")))
80 void*
81 operator new[](size_t size)
82 #if !__has_feature(cxx_noexcept)
83     throw(std::bad_alloc)
84 #endif
85 {
86     return ::operator new(size);
87 }
88 
89 __attribute__((__weak__, __visibility__("default")))
90 void*
91 operator new[](size_t size, const std::nothrow_t&) _NOEXCEPT
92 {
93     void* p = 0;
94 #ifndef _LIBCPP_NO_EXCEPTIONS
95     try
96     {
97 #endif  // _LIBCPP_NO_EXCEPTIONS
98         p = ::operator new[](size);
99 #ifndef _LIBCPP_NO_EXCEPTIONS
100     }
101     catch (...)
102     {
103     }
104 #endif  // _LIBCPP_NO_EXCEPTIONS
105     return p;
106 }
107 
108 __attribute__((__weak__, __visibility__("default")))
109 void
110 operator delete(void* ptr) _NOEXCEPT
111 {
112     if (ptr)
113         ::free(ptr);
114 }
115 
116 __attribute__((__weak__, __visibility__("default")))
117 void
118 operator delete(void* ptr, const std::nothrow_t&) _NOEXCEPT
119 {
120     ::operator delete(ptr);
121 }
122 
123 __attribute__((__weak__, __visibility__("default")))
124 void
125 operator delete[] (void* ptr) _NOEXCEPT
126 {
127     ::operator delete (ptr);
128 }
129 
130 __attribute__((__weak__, __visibility__("default")))
131 void
132 operator delete[] (void* ptr, const std::nothrow_t&) _NOEXCEPT
133 {
134     ::operator delete[](ptr);
135 }
136 
137 #endif
138 
139 namespace std
140 {
141 
142 const nothrow_t nothrow = {};
143 
144 #ifndef _LIBCPPABI_VERSION
145 
146 new_handler
147 set_new_handler(new_handler handler) _NOEXCEPT
148 {
149     return __sync_lock_test_and_set(&__new_handler, handler);
150 }
151 
152 new_handler
153 get_new_handler() _NOEXCEPT
154 {
155     return __sync_fetch_and_add(&__new_handler, (new_handler)0);
156 }
157 
158 bad_alloc::bad_alloc() _NOEXCEPT
159 {
160 }
161 
162 bad_alloc::~bad_alloc() _NOEXCEPT
163 {
164 }
165 
166 const char*
167 bad_alloc::what() const _NOEXCEPT
168 {
169     return "std::bad_alloc";
170 }
171 
172 bad_array_new_length::bad_array_new_length() _NOEXCEPT
173 {
174 }
175 
176 bad_array_new_length::~bad_array_new_length() _NOEXCEPT
177 {
178 }
179 
180 const char*
181 bad_array_new_length::what() const _NOEXCEPT
182 {
183     return "bad_array_new_length";
184 }
185 
186 #endif
187 
188 void
189 __throw_bad_alloc()
190 {
191 #ifndef _LIBCPP_NO_EXCEPTIONS
192     throw bad_alloc();
193 #endif
194 }
195 
196 }  // std
197