src/lib/assert-pre.h

   1 #ifndef BABELTRACE_ASSERT_PRE_INTERNAL_H
   2 #define BABELTRACE_ASSERT_PRE_INTERNAL_H
   3
   4 /*
   5  * Copyright (c) 2018 EfficiOS Inc. and Linux Foundation
   6  * Copyright (c) 2018 Philippe Proulx <pproulx@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24  * SOFTWARE.
  25  */
  26
  27 /*
  28  * The macros in this header use macros defined in "lib/logging.h".
  29  * We don't want this header to automatically include
  30  * "lib/logging.h" because you need to manually define BT_LOG_TAG
  31  * before including "lib/logging.h" and it is unexpected that you
  32  * also need to define it before including this header.
  33  *
  34  * This is a reminder that in order to use "lib/assert-pre.h", you also
  35  * need to use logging explicitly.
  36  */
  37
  38 #ifndef BT_LIB_LOG_SUPPORTED
  39 # error Include "lib/logging.h" before this header.
  40 #endif
  41
  42 #include <stdlib.h>
  43 #include <inttypes.h>
  44 #include "common/macros.h"
  45
  46 #ifdef BT_DEV_MODE
  47 /*
  48  * Asserts that the library precondition _cond is satisfied.
  49  *
  50  * If _cond is false, log a fatal statement using _fmt and the optional
  51  * arguments using BT_LIB_LOGF(), and abort.
  52  *
  53  * To assert that a postcondition is satisfied or that some internal
  54  * object/context/value is in the expected state, use BT_ASSERT().
  55  */
  56 # define BT_ASSERT_PRE(_cond, _fmt, ...)                                \
  57         do {                                                            \
  58                 if (!(_cond)) {                                         \
  59                         BT_LOGF_STR("Library precondition not satisfied; error is:"); \
  60                         BT_LIB_LOGF((_fmt), ##__VA_ARGS__);             \
  61                         BT_LOGF_STR("Aborting...");                     \
  62                         abort();                                        \
  63                 }                                                       \
  64         } while (0)
  65
  66 /*
  67  * Marks a function as being only used within a BT_ASSERT_PRE() context.
  68  */
  69 # define BT_ASSERT_PRE_FUNC
  70
  71 /*
  72  * Prints the details of an unsatisfied precondition without immediately
  73  * aborting. You should use this within a function which checks
  74  * preconditions, but which is called from a BT_ASSERT_PRE() context, so
  75  * that the function can still return its result for BT_ASSERT_PRE() to
  76  * evaluate it.
  77  *
  78  * Example:
  79  *
  80  *     BT_ASSERT_PRE_FUNC
  81  *     static inline bool check_complex_precond(...)
  82  *     {
  83  *         ...
  84  *
  85  *         if (...) {
  86  *             BT_ASSERT_PRE_MSG("Invalid object: ...", ...);
  87  *             return false;
  88  *         }
  89  *
  90  *         ...
  91  *     }
  92  *
  93  *     ...
  94  *
  95  *     BT_ASSERT_PRE(check_complex_precond(...),
  96  *                   "Precondition is not satisfied: ...", ...);
  97  */
  98 # define BT_ASSERT_PRE_MSG      BT_LIB_LOGF
  99 #else
 100 # define BT_ASSERT_PRE(_cond, _fmt, ...)        ((void) sizeof((void) (_cond), 0))
 101 # define BT_ASSERT_PRE_FUNC     __attribute__((unused))
 102 # define BT_ASSERT_PRE_MSG(_fmt, ...)
 103 #endif /* BT_DEV_MODE */
 104
 105 /*
 106  * Developer mode: asserts that a given variable is not NULL.
 107  */
 108 #define BT_ASSERT_PRE_NON_NULL(_obj, _obj_name)                         \
 109         BT_ASSERT_PRE((_obj) != NULL, "%s is NULL: ", _obj_name)
 110
 111 /*
 112  * Developer mode: asserts that a given object is NOT frozen. This macro
 113  * checks the `frozen` field of _obj.
 114  */
 115 #define BT_ASSERT_PRE_HOT(_obj, _obj_name, _fmt, ...)                   \
 116         BT_ASSERT_PRE(!(_obj)->frozen, "%s is frozen" _fmt, _obj_name,  \
 117                 ##__VA_ARGS__)
 118
 119 /*
 120  * Developer mode: asserts that a given index is less than a given size.
 121  */
 122 #define BT_ASSERT_PRE_VALID_INDEX(_index, _length)                      \
 123         BT_ASSERT_PRE((_index) < (_length),                             \
 124                 "Index is out of bounds: index=%" PRIu64 ", "           \
 125                 "count=%" PRIu64, (uint64_t) (_index), (uint64_t) (_length))
 126
 127 #endif /* BABELTRACE_ASSERT_PRE_INTERNAL_H */