src/lib/assert-cond-base.h

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright (c) 2018 EfficiOS Inc. and Linux Foundation
   5  * Copyright (c) 2018-2020 Philippe Proulx <pproulx@efficios.com>
   6  */
   7
   8 #ifndef BABELTRACE_ASSERT_COND_BASE_INTERNAL_H
   9 #define BABELTRACE_ASSERT_COND_BASE_INTERNAL_H
  10
  11 /*
  12  * The macros in this header use macros defined in "lib/logging.h". We
  13  * don't want this header to automatically include "lib/logging.h"
  14  * because you need to manually define BT_LOG_TAG before including
  15  * "lib/logging.h" and it is unexpected that you also need to define it
  16  * before including this header.
  17  *
  18  * This is a reminder that in order to use "lib/assert-cond.h", you also
  19  * need to use logging explicitly.
  20  */
  21
  22 #ifndef BT_LIB_LOG_SUPPORTED
  23 # error Include "lib/logging.h" before this header.
  24 #endif
  25
  26 #include <stdbool.h>
  27 #include <stdlib.h>
  28 #include <inttypes.h>
  29 #include "common/common.h"
  30 #include "common/macros.h"
  31
  32 /*
  33  * Prints the details of an unsatisfied precondition or postcondition
  34  * without immediately aborting. You should use this within a function
  35  * which checks preconditions or postconditions, but which is called
  36  * from a BT_ASSERT_PRE() or BT_ASSERT_POST() context, so that the
  37  * function can still return its result for
  38  * BT_ASSERT_PRE()/BT_ASSERT_POST() to evaluate it.
  39  *
  40  * Example:
  41  *
  42  *     static inline bool check_complex_precond(...)
  43  *     {
  44  *         ...
  45  *
  46  *         if (...) {
  47  *             BT_ASSERT_COND_MSG("Invalid object: ...", ...);
  48  *             return false;
  49  *         }
  50  *
  51  *         ...
  52  *     }
  53  *
  54  *     ...
  55  *
  56  *     BT_ASSERT_PRE(check_complex_precond(...),
  57  *                   "Precondition is not satisfied: ...", ...);
  58  */
  59 #define BT_ASSERT_COND_MSG(_fmt, ...)                                   \
  60         do {                                                            \
  61                 bt_lib_log(_BT_LOG_SRCLOC_FUNCTION, __FILE__,           \
  62                         __LINE__, BT_LOG_FATAL, BT_LOG_TAG,             \
  63                         (_fmt), ##__VA_ARGS__);                         \
  64         } while (0)
  65
  66 /*
  67  * This function:
  68  *
  69  * 1. Generates a condition ID based on `cond_type`, `func`, and
  70  *    `id_suffix`.
  71  *
  72  * 2. Logs (FATAL level) the generated condition ID and function name
  73  *    (`func`).
  74  *
  75  * 3. Logs (FATAL level) a message using `fmt` and the optional
  76  *    arguments (same usage as BT_LIB_LOGF()).
  77  *
  78  * 4. Aborts.
  79  */
  80 __attribute__((noreturn))
  81 void bt_lib_assert_cond_failed(const char *cond_type, const char *func,
  82                 const char *id_suffix, const char *fmt, ...);
  83
  84 /*
  85  * Internal to this file: asserts that the library condition `_cond` of
  86  * type `_cond_type` (`pre` or `post`), related to function `_func`,
  87  * and having the ID suffix `_id_suffix` is satisfied.
  88  *
  89  * If `_cond` is false, then this macro calls
  90  * bt_lib_assert_cond_failed().
  91  *
  92  * To assert that an _internal_ precondition or postcondition is
  93  * satisfied, use BT_ASSERT() or BT_ASSERT_DBG().
  94  */
  95 #define _BT_ASSERT_COND(_cond_type, _func, _id_suffix, _cond, _fmt, ...) \
  96         do {                                                            \
  97                 if (!(_cond)) {                                         \
  98                         bt_lib_assert_cond_failed(_cond_type, _func,    \
  99                                 _id_suffix, _fmt, ##__VA_ARGS__);       \
 100                 }                                                       \
 101         } while (0)
 102
 103 /*
 104  * Asserts that the library precondition `_cond` is satisfied.
 105  *
 106  * See _BT_ASSERT_COND() for details about the `_func` and `_id_suffix`
 107  * parameters.
 108  */
 109 #define BT_ASSERT_PRE_FROM_FUNC(_func, _id_suffix, _cond, _fmt, ...)    \
 110         _BT_ASSERT_COND("pre", _func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 111
 112 /*
 113  * Like BT_ASSERT_PRE_FROM_FUNC(), but uses `__func__` (current function
 114  * name) as the `_func` parameter.
 115  */
 116 #define BT_ASSERT_PRE(_id_suffix, _cond, _fmt, ...)                     \
 117         BT_ASSERT_PRE_FROM_FUNC(__func__, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 118
 119 /*
 120  * Asserts that the library postcondition `_cond` is satisfied.
 121  *
 122  * See _BT_ASSERT_COND() for details about the `_func` and `_id_suffix`
 123  * parameters.
 124  */
 125 #define BT_ASSERT_POST(_func, _id_suffix, _cond, _fmt, ...)                             \
 126         _BT_ASSERT_COND("post", _func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__);
 127
 128 #ifdef BT_DEV_MODE
 129 /* Developer mode version of BT_ASSERT_PRE_FROM_FUNC(). */
 130 # define BT_ASSERT_PRE_DEV_FROM_FUNC(_func, _id_suffix, _cond, _fmt, ...) \
 131         BT_ASSERT_PRE_FROM_FUNC(_func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 132
 133 /* Developer mode version of BT_ASSERT_PRE(). */
 134 # define BT_ASSERT_PRE_DEV(_id_suffix, _cond, _fmt, ...)                \
 135         BT_ASSERT_PRE(_id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 136
 137 /* Developer mode version of BT_ASSERT_POST(). */
 138 # define BT_ASSERT_POST_DEV(_func, _id_suffix, _cond, _fmt, ...)        \
 139         BT_ASSERT_POST(_func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 140
 141 /* Developer mode version of BT_ASSERT_COND_MSG(). */
 142 # define BT_ASSERT_COND_DEV_MSG(_fmt, ...)                              \
 143         BT_ASSERT_COND_MSG(_fmt, ##__VA_ARGS__)
 144
 145 /*
 146  * Marks a function as being only used within a BT_ASSERT_PRE_DEV() or
 147  * BT_ASSERT_POST_DEV() context.
 148  */
 149 # define BT_ASSERT_COND_DEV_FUNC
 150 #else
 151 # define BT_ASSERT_COND_DEV_MSG(_fmt, ...)
 152
 153 # define BT_ASSERT_PRE_DEV_FROM_FUNC(_func, _id_suffix, _cond, _fmt, ...) \
 154         BT_USE_EXPR4(_func, _id_suffix, _cond, _fmt)
 155
 156 # define BT_ASSERT_PRE_DEV(_id_suffix, _cond, _fmt, ...)                \
 157         BT_USE_EXPR3(_id_suffix, _cond, _fmt)
 158
 159 # define BT_ASSERT_POST_DEV(_func, _id_suffix, _cond, _fmt, ...)        \
 160         BT_USE_EXPR4(_func, _id_suffix, _cond, _fmt)
 161
 162 # define BT_ASSERT_COND_DEV_FUNC        __attribute__((unused))
 163 #endif /* BT_DEV_MODE */
 164
 165 /*
 166  * Mark anything that includes this file as supporting precondition and
 167  * postcondition assertion macros.
 168  */
 169 #define BT_ASSERT_COND_SUPPORTED
 170
 171 #endif /* BABELTRACE_ASSERT_COND_BASE_INTERNAL_H */