projects / libside.git / blame
| Commit | Line | Data |
|---|---|---|
| 2e197497 MD |
1 | // SPDX-License-Identifier: MIT |
| 2 | /* | |
| 3 | * Copyright 2022 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 4 | */ | |
| 5 | ||
| 6 | #ifndef _SIDE_MACROS_H | |
| 7 | #define _SIDE_MACROS_H | |
| 8 | ||
| 9 | #include <stddef.h> | |
| 10 | #include <limits.h> | |
| 11 | ||
| 12 | /* Helper macros */ | |
| 13 | ||
| 14 | #define SIDE_ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) | |
| 15 | ||
| 16 | /* | |
| 17 | * Compound literals with static storage are needed by SIDE | |
| 18 | * instrumentation. | |
| 19 | * Compound literals are part of the C99 and C11 standards, but not | |
| 20 | * part of the C++ standards. They are supported by most C++ compilers | |
| 21 | * though. | |
| 22 | * | |
| 23 | * Example use: | |
| 24 | * static struct mystruct *var = LTTNG_UST_COMPOUND_LITERAL(struct mystruct, { 1, 2, 3 }); | |
| 25 | */ | |
| 26 | #define SIDE_COMPOUND_LITERAL(type, ...) (type[]) { __VA_ARGS__ } | |
| 27 | ||
| 28 | #define side_likely(x) __builtin_expect(!!(x), 1) | |
| 29 | #define side_unlikely(x) __builtin_expect(!!(x), 0) | |
| 30 | ||
| 31 | #define SIDE_PARAM(...) __VA_ARGS__ | |
| 32 | ||
| 33 | /* Select arg1 in list of arguments. */ | |
| 34 | #define SIDE_PARAM_SELECT_ARG1(_arg0, _arg1, ...) _arg1 | |
| 35 | ||
| 36 | /* | |
| 37 | * Use the default parameter if no additional arguments are provided, | |
| 38 | .* else use the following arguments. Use inside macros to implement | |
| 39 | * optional last macro argument. | |
| 40 | */ | |
| 41 | #define SIDE_PARAM_DEFAULT(_default, ...) \ | |
| 42 | SIDE_PARAM_SELECT_ARG1(dummy, ##__VA_ARGS__, _default) | |
| 43 | ||
| 44 | /* | |
| 45 | * side_container_of - Get the address of an object containing a field. | |
| 46 | * | |
| 47 | * @ptr: pointer to the field. | |
| 48 | * @type: type of the object. | |
| 49 | * @member: name of the field within the object. | |
| 50 | */ | |
| 51 | #define side_container_of(ptr, type, member) \ | |
| 52 | __extension__ \ | |
| 53 | ({ \ | |
| 54 | const __typeof__(((type *) NULL)->member) * __ptr = (ptr); \ | |
| 55 | (type *)((char *)__ptr - offsetof(type, member)); \ | |
| 56 | }) | |
| 57 | ||
| 58 | #define side_struct_field_sizeof(_struct, _field) \ | |
| 59 | sizeof(((_struct * )NULL)->_field) | |
| 60 | ||
| 61 | #if defined(__SIZEOF_LONG__) | |
| 62 | #define SIDE_BITS_PER_LONG (__SIZEOF_LONG__ * 8) | |
| 63 | #elif defined(_LP64) | |
| 64 | #define SIDE_BITS_PER_LONG 64 | |
| 65 | #else | |
| 66 | #define SIDE_BITS_PER_LONG 32 | |
| 67 | #endif | |
| 68 | ||
| 69 | #define SIDE_PACKED __attribute__((packed)) | |
| 70 | ||
| 71 | #endif /* _SIDE_MACROS_H */ |