Line data    Source code

       1             : // Copyright (c) 2019-2021 The Bitcoin Core developers
       2             : // Distributed under the MIT software license, see the accompanying
       3             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       4             : 
       5             : #ifndef BITCOIN_UTIL_CHECK_H
       6             : #define BITCOIN_UTIL_CHECK_H
       7             : 
       8             : #include <attributes.h>
       9             : 
      10             : #include <stdexcept>
      11             : #include <utility>
      12             : 
      13             : std::string StrFormatInternalBug(const char* msg, const char* file, int line, const char* func);
      14             : 
      15             : class NonFatalCheckError : public std::runtime_error
      16             : {
      17             : public:
      18             :     NonFatalCheckError(const char* msg, const char* file, int line, const char* func);
      19             : };
      20             : 
      21             : #define STR_INTERNAL_BUG(msg) StrFormatInternalBug((msg), __FILE__, __LINE__, __func__)
      22             : 
      23             : /** Helper for CHECK_NONFATAL() */
      24             : template <typename T>
      25      338584 : T&& inline_check_non_fatal(LIFETIMEBOUND T&& val, const char* file, int line, const char* func, const char* assertion)
      26             : {
      27      338584 :     if (!val) {
      28           0 :         throw NonFatalCheckError{assertion, file, line, func};
      29             :     }
      30      338584 :     return std::forward<T>(val);
      31           0 : }
      32             : 
      33             : /**
      34             :  * Identity function. Throw a NonFatalCheckError when the condition evaluates to false
      35             :  *
      36             :  * This should only be used
      37             :  * - where the condition is assumed to be true, not for error handling or validating user input
      38             :  * - where a failure to fulfill the condition is recoverable and does not abort the program
      39             :  *
      40             :  * For example in RPC code, where it is undesirable to crash the whole program, this can be generally used to replace
      41             :  * asserts or recoverable logic errors. A NonFatalCheckError in RPC code is caught and passed as a string to the RPC
      42             :  * caller, which can then report the issue to the developers.
      43             :  */
      44             : #define CHECK_NONFATAL(condition) \
      45             :     inline_check_non_fatal(condition, __FILE__, __LINE__, __func__, #condition)
      46             : 
      47             : #if defined(NDEBUG)
      48             : #error "Cannot compile without assertions!"
      49             : #endif
      50             : 
      51             : /** Helper for Assert() */
      52             : void assertion_fail(const char* file, int line, const char* func, const char* assertion);
      53             : 
      54             : /** Helper for Assert()/Assume() */
      55             : template <bool IS_ASSERT, typename T>
      56     5680840 : T&& inline_assertion_check(LIFETIMEBOUND T&& val, [[maybe_unused]] const char* file, [[maybe_unused]] int line, [[maybe_unused]] const char* func, [[maybe_unused]] const char* assertion)
      57             : {
      58             :     if constexpr (IS_ASSERT
      59             : #ifdef ABORT_ON_FAILED_ASSUME
      60             :                   || true
      61             : #endif
      62             :     ) {
      63      594018 :         if (!val) {
      64           0 :             assertion_fail(file, line, func, assertion);
      65           0 :         }
      66             :     }
      67     5680840 :     return std::forward<T>(val);
      68             : }
      69             : 
      70             : /** Identity function. Abort if the value compares equal to zero */
      71             : #define Assert(val) inline_assertion_check<true>(val, __FILE__, __LINE__, __func__, #val)
      72             : 
      73             : /**
      74             :  * Assume is the identity function.
      75             :  *
      76             :  * - Should be used to run non-fatal checks. In debug builds it behaves like
      77             :  *   Assert()/assert() to notify developers and testers about non-fatal errors.
      78             :  *   In production it doesn't warn or log anything.
      79             :  * - For fatal errors, use Assert().
      80             :  * - For non-fatal errors in interactive sessions (e.g. RPC or command line
      81             :  *   interfaces), CHECK_NONFATAL() might be more appropriate.
      82             :  */
      83             : #define Assume(val) inline_assertion_check<false>(val, __FILE__, __LINE__, __func__, #val)
      84             : 
      85             : /**
      86             :  * NONFATAL_UNREACHABLE() is a macro that is used to mark unreachable code. It throws a NonFatalCheckError.
      87             :  */
      88             : #define NONFATAL_UNREACHABLE()                                        \
      89             :     throw NonFatalCheckError(                                         \
      90             :         "Unreachable code reached (non-fatal)", __FILE__, __LINE__, __func__)
      91             : 
      92             : #endif // BITCOIN_UTIL_CHECK_H