Line data    Source code

       1             : // Copyright (c) 2019-2022 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 <string>
      12             : #include <string_view>
      13             : #include <utility>
      14             : 
      15             : std::string StrFormatInternalBug(std::string_view msg, std::string_view file, int line, std::string_view func);
      16             : 
      17             : class NonFatalCheckError : public std::runtime_error
      18             : {
      19             : public:
      20             :     NonFatalCheckError(std::string_view msg, std::string_view file, int line, std::string_view func);
      21             : };
      22             : 
      23             : #define STR_INTERNAL_BUG(msg) StrFormatInternalBug((msg), __FILE__, __LINE__, __func__)
      24             : 
      25             : /** Helper for CHECK_NONFATAL() */
      26             : template <typename T>
      27        3119 : T&& inline_check_non_fatal(LIFETIMEBOUND T&& val, const char* file, int line, const char* func, const char* assertion)
      28             : {
      29        3119 :     if (!val) {
      30           0 :         throw NonFatalCheckError{assertion, file, line, func};
      31             :     }
      32        3119 :     return std::forward<T>(val);
      33           0 : }
      34             : 
      35             : /**
      36             :  * Identity function. Throw a NonFatalCheckError when the condition evaluates to false
      37             :  *
      38             :  * This should only be used
      39             :  * - where the condition is assumed to be true, not for error handling or validating user input
      40             :  * - where a failure to fulfill the condition is recoverable and does not abort the program
      41             :  *
      42             :  * For example in RPC code, where it is undesirable to crash the whole program, this can be generally used to replace
      43             :  * asserts or recoverable logic errors. A NonFatalCheckError in RPC code is caught and passed as a string to the RPC
      44             :  * caller, which can then report the issue to the developers.
      45             :  */
      46             : #define CHECK_NONFATAL(condition) \
      47             :     inline_check_non_fatal(condition, __FILE__, __LINE__, __func__, #condition)
      48             : 
      49             : #if defined(NDEBUG)
      50             : #error "Cannot compile without assertions!"
      51             : #endif
      52             : 
      53             : /** Helper for Assert() */
      54             : void assertion_fail(std::string_view file, int line, std::string_view func, std::string_view assertion);
      55             : 
      56             : /** Helper for Assert()/Assume() */
      57             : template <bool IS_ASSERT, typename T>
      58     1181390 : 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)
      59             : {
      60             :     if constexpr (IS_ASSERT
      61             : #ifdef ABORT_ON_FAILED_ASSUME
      62             :                   || true
      63             : #endif
      64             :     ) {
      65     1181390 :         if (!val) {
      66           0 :             assertion_fail(file, line, func, assertion);
      67           0 :         }
      68             :     }
      69     1181390 :     return std::forward<T>(val);
      70             : }
      71             : 
      72             : /** Identity function. Abort if the value compares equal to zero */
      73             : #define Assert(val) inline_assertion_check<true>(val, __FILE__, __LINE__, __func__, #val)
      74             : 
      75             : /**
      76             :  * Assume is the identity function.
      77             :  *
      78             :  * - Should be used to run non-fatal checks. In debug builds it behaves like
      79             :  *   Assert()/assert() to notify developers and testers about non-fatal errors.
      80             :  *   In production it doesn't warn or log anything.
      81             :  * - For fatal errors, use Assert().
      82             :  * - For non-fatal errors in interactive sessions (e.g. RPC or command line
      83             :  *   interfaces), CHECK_NONFATAL() might be more appropriate.
      84             :  */
      85             : #define Assume(val) inline_assertion_check<false>(val, __FILE__, __LINE__, __func__, #val)
      86             : 
      87             : /**
      88             :  * NONFATAL_UNREACHABLE() is a macro that is used to mark unreachable code. It throws a NonFatalCheckError.
      89             :  */
      90             : #define NONFATAL_UNREACHABLE()                                        \
      91             :     throw NonFatalCheckError(                                         \
      92             :         "Unreachable code reached (non-fatal)", __FILE__, __LINE__, __func__)
      93             : 
      94             : #endif // BITCOIN_UTIL_CHECK_H