1 /*
2  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
3  *
4  * This Source Code Form is subject to the terms of the Mozilla Public
5  * License, v. 2.0. If a copy of the MPL was not distributed with this
6  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
7  *
8  * See the COPYRIGHT file distributed with this work for additional
9  * information regarding copyright ownership.
10  */
11 
12 #pragma once
13 
14 #if HAVE_FUNC_ATTRIBUTE_NORETURN
15 #define ISC_NORETURN __attribute__((noreturn))
16 #else
17 #define ISC_NORETURN
18 #endif
19 
20 #if HAVE_FUNC_ATTRIBUTE_RETURNS_NONNULL
21 #define ISC_ATTR_RETURNS_NONNULL __attribute__((returns_nonnull))
22 #else
23 #define ISC_ATTR_RETURNS_NONNULL
24 #endif
25 
26 #ifdef HAVE_FUNC_ATTRIBUTE_MALLOC
27 /*
28  * Indicates that a function is malloc-like, i.e., that the
29  * pointer P returned by the function cannot alias any other
30  * pointer valid when the function returns.
31  */
32 #define ISC_ATTR_MALLOC __attribute__((malloc))
33 #if HAVE_MALLOC_EXT_ATTR
34 /*
35  * Associates deallocator as a suitable deallocation function
36  * for pointers returned from the function marked with the attribute.
37  */
38 #define ISC_ATTR_DEALLOCATOR(deallocator) __attribute__((malloc(deallocator)))
39 /*
40  * Similar to ISC_ATTR_DEALLOCATOR, but allows to speficy an index "idx",
41  * which denotes the positional argument to which when the pointer is passed
42  * in calls to deallocator has the effect of deallocating it.
43  */
44 #define ISC_ATTR_DEALLOCATOR_IDX(deallocator, idx) \
45 	__attribute__((malloc(deallocator, idx)))
46 /*
47  * Combines both ISC_ATTR_MALLOC and ISC_ATTR_DEALLOCATOR attributes.
48  */
49 #define ISC_ATTR_MALLOC_DEALLOCATOR(deallocator) \
50 	__attribute__((malloc, malloc(deallocator)))
51 /*
52  * Similar to ISC_ATTR_MALLOC_DEALLOCATOR, but allows to speficy an index "idx",
53  * which denotes the positional argument to which when the pointer is passed
54  * in calls to deallocator has the effect of deallocating it.
55  */
56 #define ISC_ATTR_MALLOC_DEALLOCATOR_IDX(deallocator, idx) \
57 	__attribute__((malloc, malloc(deallocator, idx)))
58 #else /* #ifdef HAVE_MALLOC_EXT_ATTR */
59 /*
60  * There is support for malloc attribute but not for
61  * extended attributes, so macros that combine attribute malloc
62  * with a deallocator will only expand to malloc attribute.
63  */
64 #define ISC_ATTR_DEALLOCATOR(deallocator)
65 #define ISC_ATTR_DEALLOCATOR_IDX(deallocator, idx)
66 #define ISC_ATTR_MALLOC_DEALLOCATOR(deallocator)	  ISC_ATTR_MALLOC
67 #define ISC_ATTR_MALLOC_DEALLOCATOR_IDX(deallocator, idx) ISC_ATTR_MALLOC
68 #endif
69 #else /* #ifdef HAVE_FUNC_ATTRIBUTE_MALLOC */
70 /*
71  * There is no support for malloc attribute.
72  */
73 #define ISC_ATTR_MALLOC
74 #define ISC_ATTR_DEALLOCATOR(deallocator)
75 #define ISC_ATTR_DEALLOCATOR_IDX(deallocator, idx)
76 #define ISC_ATTR_MALLOC_DEALLOCATOR(deallocator)
77 #define ISC_ATTR_MALLOC_DEALLOCATOR_IDX(deallocator, idx)
78 #endif /* HAVE_FUNC_ATTRIBUTE_MALLOC */
79