projects / lttng-tools.git / blame
| Commit | Line | Data |
|---|---|---|
| 990570ed DG |
1 | /* |
| 2 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> | |
| 3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 4 | * | |
| d14d33bf AM |
5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License, version 2 only, | |
| 7 | * as published by the Free Software Foundation. | |
| 990570ed DG |
8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| d14d33bf | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 990570ed DG |
12 | * more details. |
| 13 | * | |
| d14d33bf AM |
14 | * You should have received a copy of the GNU General Public License along |
| 15 | * with this program; if not, write to the Free Software Foundation, Inc., | |
| 16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 990570ed DG |
17 | */ |
| 18 | ||
| 19 | #ifndef _MACROS_H | |
| 20 | #define _MACROS_H | |
| 21 | ||
| 22 | #include <stdlib.h> | |
| b8d89ea6 | 23 | #include <string.h> |
| 990570ed DG |
24 | |
| 25 | /* | |
| 26 | * Takes a pointer x and transform it so we can use it to access members | |
| 27 | * without a function call. Here an example: | |
| 28 | * | |
| 29 | * #define GET_SIZE(x) LTTNG_REF(x)->size | |
| 30 | * | |
| 31 | * struct { int size; } s; | |
| 32 | * | |
| 33 | * printf("size : %d\n", GET_SIZE(&s)); | |
| 34 | * | |
| 35 | * For this example we can't use something like this for compatibility purpose | |
| 36 | * since this will fail: | |
| 37 | * | |
| 38 | * #define GET_SIZE(x) x->size; | |
| 39 | * | |
| 40 | * This is mostly use for the compatibility layer of lttng-tools. See | |
| 41 | * poll/epoll for a good example. Since x can be on the stack or allocated | |
| 42 | * memory using malloc(), we must use generic accessors for compat in order to | |
| 43 | * *not* use a function to access members and not the variable name. | |
| 44 | */ | |
| 45 | #define LTTNG_REF(x) ((typeof(*x) *)(x)) | |
| 46 | ||
| 47 | /* | |
| 48 | * Memory allocation zeroed | |
| 49 | */ | |
| 50 | #define zmalloc(x) calloc(1, x) | |
| 51 | ||
| 52 | #ifndef ARRAY_SIZE | |
| 53 | #define ARRAY_SIZE(array) (sizeof(array) / (sizeof((array)[0]))) | |
| 54 | #endif | |
| 55 | ||
| cf3f19ae SM |
56 | #ifndef max |
| 57 | #define max(a, b) ((a) > (b) ? (a) : (b)) | |
| 58 | #endif | |
| 59 | ||
| 331744e3 JD |
60 | #ifndef max_t |
| 61 | #define max_t(type, a, b) ((type) max(a, b)) | |
| 62 | #endif | |
| 63 | ||
| cf3f19ae SM |
64 | #ifndef min |
| 65 | #define min(a, b) ((a) < (b) ? (a) : (b)) | |
| 66 | #endif | |
| 67 | ||
| 54c90d10 DG |
68 | #ifndef LTTNG_PACKED |
| 69 | #define LTTNG_PACKED __attribute__((__packed__)) | |
| 70 | #endif | |
| 71 | ||
| 99c815c1 DG |
72 | #ifndef LTTNG_HIDDEN |
| 73 | #define LTTNG_HIDDEN __attribute__((visibility("hidden"))) | |
| 74 | #endif | |
| 75 | ||
| b8d89ea6 MD |
76 | /* |
| 77 | * lttng_strncpy returns 0 on success, or nonzero on failure. | |
| 78 | * It checks that the @src string fits into @dst_len before performing | |
| 79 | * the copy. On failure, no copy has been performed. | |
| 80 | * | |
| 81 | * dst_len includes the string's trailing NULL. | |
| 82 | */ | |
| 83 | static inline | |
| 84 | int lttng_strncpy(char *dst, const char *src, size_t dst_len) | |
| 85 | { | |
| 86 | if (strnlen(src, dst_len) == dst_len) { | |
| 87 | /* Fail since copying would result in truncation. */ | |
| 88 | return -1; | |
| 89 | } | |
| 90 | strncpy(dst, src, dst_len); | |
| 91 | /* | |
| 92 | * Be extra careful and put final \0 at the end after strncpy(), | |
| 93 | * even though we checked the length before. This makes Coverity | |
| 94 | * happy. | |
| 95 | */ | |
| 96 | dst[dst_len - 1] = '\0'; | |
| 97 | return 0; | |
| 98 | } | |
| 99 | ||
| 990570ed | 100 | #endif /* _MACROS_H */ |