xref: /freebsd/contrib/libcxxrt/memory.cc (revision d4ae33f0721c1b170fe37d97e395228ffcfb3f80)
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 
155