Line data    Source code

       1             : // Copyright (c) 2019 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             : #if defined(HAVE_CONFIG_H)
       9             : #include <config/bitcoin-config.h>
      10             : #endif
      11             : 
      12             : #include <tinyformat.h>
      13             : 
      14             : #include <stdexcept>
      15             : 
      16           8 : class NonFatalCheckError : public std::runtime_error
      17             : {
      18           8 :     using std::runtime_error::runtime_error;
      19             : };
      20             : 
      21             : /**
      22             :  * Throw a NonFatalCheckError when the condition evaluates to false
      23             :  *
      24             :  * This should only be used
      25             :  * - where the condition is assumed to be true, not for error handling or validating user input
      26             :  * - where a failure to fulfill the condition is recoverable and does not abort the program
      27             :  *
      28             :  * For example in RPC code, where it is undesirable to crash the whole program, this can be generally used to replace
      29             :  * asserts or recoverable logic errors. A NonFatalCheckError in RPC code is caught and passed as a string to the RPC
      30             :  * caller, which can then report the issue to the developers.
      31             :  */
      32             : #define CHECK_NONFATAL(condition)                                 \
      33             :     do {                                                          \
      34             :         if (!(condition)) {                                       \
      35             :             throw NonFatalCheckError(                             \
      36             :                 strprintf("%s:%d (%s)\n"                          \
      37             :                           "Internal bug detected: '%s'\n"         \
      38             :                           "You may report this issue here: %s\n", \
      39             :                     __FILE__, __LINE__, __func__,                 \
      40             :                     (#condition),                                 \
      41             :                     PACKAGE_BUGREPORT));                          \
      42             :         }                                                         \
      43             :     } while (false)
      44             : 
      45             : #if defined(NDEBUG)
      46             : #error "Cannot compile without assertions!"
      47             : #endif
      48             : 
      49             : /** Helper for Assert(). TODO remove in C++14 and replace `decltype(get_pure_r_value(val))` with `T` (templated lambda) */
      50             : template <typename T>
      51             : T get_pure_r_value(T&& val)
      52             : {
      53             :     return std::forward<T>(val);
      54             : }
      55             : 
      56             : /** Identity function. Abort if the value compares equal to zero */
      57             : #define Assert(val) [&]() -> decltype(get_pure_r_value(val)) { auto&& check = (val); assert(#val && check); return std::forward<decltype(get_pure_r_value(val))>(check); }()
      58             : 
      59             : #endif // BITCOIN_UTIL_CHECK_H