xref: /freebsd/contrib/libcxxrt/memory.cc (revision b0b1dbdd)
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 #if __cplusplus < 201103L
75 #define NOEXCEPT throw()
76 #define BADALLOC throw(std::bad_alloc)
77 #else
78 #define NOEXCEPT noexcept
79 #define BADALLOC
80 #endif
81 
82 
83 __attribute__((weak))
84 void* operator new(size_t size) BADALLOC
85 {
86 	if (0 == size)
87 	{
88 		size = 1;
89 	}
90 	void * mem = malloc(size);
91 	while (0 == mem)
92 	{
93 		new_handler h = std::get_new_handler();
94 		if (0 != h)
95 		{
96 			h();
97 		}
98 		else
99 		{
100 			throw std::bad_alloc();
101 		}
102 		mem = malloc(size);
103 	}
104 
105 	return mem;
106 }
107 
108 __attribute__((weak))
109 void* operator new(size_t size, const std::nothrow_t &) NOEXCEPT
110 {
111 	try {
112 		return :: operator new(size);
113 	} catch (...) {
114 		// nothrow operator new should return NULL in case of
115 		// std::bad_alloc exception in new handler
116 		return NULL;
117 	}
118 }
119 
120 
121 __attribute__((weak))
122 void operator delete(void * ptr) NOEXCEPT
123 {
124 	free(ptr);
125 }
126 
127 
128 __attribute__((weak))
129 void * operator new[](size_t size) BADALLOC
130 {
131 	return ::operator new(size);
132 }
133 
134 
135 __attribute__((weak))
136 void * operator new[](size_t size, const std::nothrow_t &) NOEXCEPT
137 {
138 	try {
139 		return ::operator new[](size);
140 	} catch (...) {
141 		// nothrow operator new should return NULL in case of
142 		// std::bad_alloc exception in new handler
143 		return NULL;
144 	}
145 }
146 
147 
148 __attribute__((weak))
149 void operator delete[](void * ptr) NOEXCEPT
150 {
151 	::operator delete(ptr);
152 }
153 
154 
155