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 BT_HIDDEN
  81 __attribute__((noreturn))
  82 void bt_lib_assert_cond_failed(const char *cond_type, const char *func,
  83                 const char *id_suffix, const char *fmt, ...);
  84
  85 /*
  86  * Internal to this file: asserts that the library condition `_cond` of
  87  * type `_cond_type` (`pre` or `post`), related to function `_func`,
  88  * and having the ID suffix `_id_suffix` is satisfied.
  89  *
  90  * If `_cond` is false, then this macro calls
  91  * bt_lib_assert_cond_failed().
  92  *
  93  * To assert that an _internal_ precondition or postcondition is
  94  * satisfied, use BT_ASSERT() or BT_ASSERT_DBG().
  95  */
  96 #define _BT_ASSERT_COND(_cond_type, _func, _id_suffix, _cond, _fmt, ...) \
  97         do {                                                            \
  98                 if (!(_cond)) {                                         \
  99                         bt_lib_assert_cond_failed(_cond_type, _func,    \
 100                                 _id_suffix, _fmt, ##__VA_ARGS__);       \
 101                 }                                                       \
 102         } while (0)
 103
 104 /*
 105  * Asserts that the library precondition `_cond` is satisfied.
 106  *
 107  * See _BT_ASSERT_COND() for details about the `_func` and `_id_suffix`
 108  * parameters.
 109  */
 110 #define BT_ASSERT_PRE_FROM_FUNC(_func, _id_suffix, _cond, _fmt, ...)    \
 111         _BT_ASSERT_COND("pre", _func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 112
 113 /*
 114  * Like BT_ASSERT_PRE_FROM_FUNC(), but uses `__func__` (current function
 115  * name) as the `_func` parameter.
 116  */
 117 #define BT_ASSERT_PRE(_id_suffix, _cond, _fmt, ...)                     \
 118         BT_ASSERT_PRE_FROM_FUNC(__func__, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 119
 120 /*
 121  * Asserts that the library postcondition `_cond` is satisfied.
 122  *
 123  * See _BT_ASSERT_COND() for details about the `_func` and `_id_suffix`
 124  * parameters.
 125  */
 126 #define BT_ASSERT_POST(_func, _id_suffix, _cond, _fmt, ...)                             \
 127         _BT_ASSERT_COND("post", _func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__);
 128
 129 #ifdef BT_DEV_MODE
 130 /* Developer mode version of BT_ASSERT_PRE_FROM_FUNC(). */
 131 # define BT_ASSERT_PRE_DEV_FROM_FUNC(_func, _id_suffix, _cond, _fmt, ...) \
 132         BT_ASSERT_PRE_FROM_FUNC(_func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 133
 134 /* Developer mode version of BT_ASSERT_PRE(). */
 135 # define BT_ASSERT_PRE_DEV(_id_suffix, _cond, _fmt, ...)                \
 136         BT_ASSERT_PRE(_id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 137
 138 /* Developer mode version of BT_ASSERT_POST(). */
 139 # define BT_ASSERT_POST_DEV(_func, _id_suffix, _cond, _fmt, ...)        \
 140         BT_ASSERT_POST(_func, _id_suffix, (_cond), _fmt, ##__VA_ARGS__)
 141
 142 /* Developer mode version of BT_ASSERT_COND_MSG(). */
 143 # define BT_ASSERT_COND_DEV_MSG(_fmt, ...)                              \
 144         BT_ASSERT_COND_MSG(_fmt, ##__VA_ARGS__)
 145
 146 /*
 147  * Marks a function as being only used within a BT_ASSERT_PRE_DEV() or
 148  * BT_ASSERT_POST_DEV() context.
 149  */
 150 # define BT_ASSERT_COND_DEV_FUNC
 151 #else
 152 # define BT_ASSERT_COND_DEV_MSG(_fmt, ...)
 153
 154 # define BT_ASSERT_PRE_DEV_FROM_FUNC(_func, _id_suffix, _cond, _fmt, ...) \
 155         BT_USE_EXPR4(_func, _id_suffix, _cond, _fmt)
 156
 157 # define BT_ASSERT_PRE_DEV(_id_suffix, _cond, _fmt, ...)                \
 158         BT_USE_EXPR3(_id_suffix, _cond, _fmt)
 159
 160 # define BT_ASSERT_POST_DEV(_func, _id_suffix, _cond, _fmt, ...)        \
 161         BT_USE_EXPR4(_func, _id_suffix, _cond, _fmt)
 162
 163 # define BT_ASSERT_COND_DEV_FUNC        __attribute__((unused))
 164 #endif /* BT_DEV_MODE */
 165
 166 /*
 167  * Mark anything that includes this file as supporting precondition and
 168  * postcondition assertion macros.
 169  */
 170 #define BT_ASSERT_COND_SUPPORTED
 171
 172 #endif /* BABELTRACE_ASSERT_COND_BASE_INTERNAL_H */