Commit | Line | Data |
---|---|---|
990570ed | 1 | /* |
ab5be9fa MJ |
2 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> |
3 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
990570ed | 4 | * |
ab5be9fa | 5 | * SPDX-License-Identifier: GPL-2.0-only |
990570ed | 6 | * |
990570ed DG |
7 | */ |
8 | ||
9 | #ifndef _MACROS_H | |
10 | #define _MACROS_H | |
11 | ||
12 | #include <stdlib.h> | |
93375aa6 | 13 | #include <stddef.h> |
f6835b82 | 14 | #include <string.h> |
639082d2 | 15 | #include <common/compat/string.h> |
990570ed DG |
16 | |
17 | /* | |
18 | * Takes a pointer x and transform it so we can use it to access members | |
19 | * without a function call. Here an example: | |
20 | * | |
21 | * #define GET_SIZE(x) LTTNG_REF(x)->size | |
22 | * | |
23 | * struct { int size; } s; | |
24 | * | |
25 | * printf("size : %d\n", GET_SIZE(&s)); | |
26 | * | |
27 | * For this example we can't use something like this for compatibility purpose | |
28 | * since this will fail: | |
29 | * | |
30 | * #define GET_SIZE(x) x->size; | |
31 | * | |
32 | * This is mostly use for the compatibility layer of lttng-tools. See | |
33 | * poll/epoll for a good example. Since x can be on the stack or allocated | |
34 | * memory using malloc(), we must use generic accessors for compat in order to | |
35 | * *not* use a function to access members and not the variable name. | |
36 | */ | |
37 | #define LTTNG_REF(x) ((typeof(*x) *)(x)) | |
38 | ||
39 | /* | |
40 | * Memory allocation zeroed | |
41 | */ | |
4616a46c MD |
42 | static inline |
43 | void *zmalloc(size_t len) | |
44 | { | |
45 | return calloc(1, len); | |
46 | } | |
990570ed DG |
47 | |
48 | #ifndef ARRAY_SIZE | |
49 | #define ARRAY_SIZE(array) (sizeof(array) / (sizeof((array)[0]))) | |
50 | #endif | |
51 | ||
93375aa6 JG |
52 | #ifndef container_of |
53 | #define container_of(ptr, type, member) \ | |
54 | ({ \ | |
55 | const typeof(((type *)NULL)->member) * __ptr = (ptr); \ | |
56 | (type *)((char *)__ptr - offsetof(type, member)); \ | |
57 | }) | |
58 | #endif | |
59 | ||
cf3f19ae SM |
60 | #ifndef max |
61 | #define max(a, b) ((a) > (b) ? (a) : (b)) | |
62 | #endif | |
63 | ||
331744e3 | 64 | #ifndef max_t |
46e3b92d | 65 | #define max_t(type, a, b) max((type) a, (type) b) |
331744e3 JD |
66 | #endif |
67 | ||
cf3f19ae SM |
68 | #ifndef min |
69 | #define min(a, b) ((a) < (b) ? (a) : (b)) | |
70 | #endif | |
71 | ||
d0927b41 | 72 | #ifndef min_t |
46e3b92d | 73 | #define min_t(type, a, b) min((type) a, (type) b) |
d0927b41 FD |
74 | #endif |
75 | ||
54c90d10 DG |
76 | #ifndef LTTNG_PACKED |
77 | #define LTTNG_PACKED __attribute__((__packed__)) | |
78 | #endif | |
79 | ||
1405051a FD |
80 | #ifndef LTTNG_NO_SANITIZE_ADDRESS |
81 | #if defined(__clang__) || defined (__GNUC__) | |
82 | #define LTTNG_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address)) | |
83 | #else | |
84 | #define LTTNG_NO_SANITIZE_ADDRESS | |
85 | #endif | |
86 | #endif | |
87 | ||
159b042f JG |
88 | #define is_signed(type) (((type) (-1)) < 0) |
89 | ||
eac6ee11 JG |
90 | /* |
91 | * Align value to the next multiple of align. Returns val if it already is a | |
92 | * multiple of align. Align must be a power of two. | |
93 | */ | |
94 | #define ALIGN_TO(value, align) ((value + (align - 1)) & ~(align - 1)) | |
95 | ||
70c6956b MJ |
96 | /* |
97 | * LTTNG_HIDDEN: set the hidden attribute for internal functions | |
98 | * On Windows, symbols are local unless explicitly exported, | |
99 | * see https://gcc.gnu.org/wiki/Visibility | |
100 | */ | |
101 | #if defined(_WIN32) || defined(__CYGWIN__) | |
102 | #define LTTNG_HIDDEN | |
103 | #else | |
99c815c1 DG |
104 | #define LTTNG_HIDDEN __attribute__((visibility("hidden"))) |
105 | #endif | |
106 | ||
f8f3885c MD |
107 | #define member_sizeof(type, field) sizeof(((type *) 0)->field) |
108 | ||
5e5c14ce JG |
109 | #define ASSERT_LOCKED(lock) assert(pthread_mutex_trylock(&lock)) |
110 | ||
1a65bbb8 JG |
111 | /* |
112 | * Get an aligned pointer to a value. This is meant | |
113 | * as a helper to pass an aligned pointer to a member in a packed structure | |
114 | * to a function. | |
115 | */ | |
116 | #define ALIGNED_CONST_PTR(value) (((const typeof(value) []) { value })) | |
117 | ||
f6835b82 MD |
118 | /* |
119 | * lttng_strncpy returns 0 on success, or nonzero on failure. | |
120 | * It checks that the @src string fits into @dst_len before performing | |
121 | * the copy. On failure, no copy has been performed. | |
122 | * | |
123 | * dst_len includes the string's trailing NULL. | |
124 | */ | |
125 | static inline | |
126 | int lttng_strncpy(char *dst, const char *src, size_t dst_len) | |
127 | { | |
c3ef76cd | 128 | if (lttng_strnlen(src, dst_len) >= dst_len) { |
f6835b82 MD |
129 | /* Fail since copying would result in truncation. */ |
130 | return -1; | |
131 | } | |
c3ef76cd | 132 | strcpy(dst, src); |
f6835b82 MD |
133 | return 0; |
134 | } | |
135 | ||
990570ed | 136 | #endif /* _MACROS_H */ |