SFTK/include/exceptions.hpp

#ifndef EXCEPTIONS_HPP
#define EXCEPTIONS_HPP

#include <exception>
#include <sstream>
#include <iomanip>

namespace sftk
{
    /**
     * @brief # SFTK exceptions super class
     *
     * @tparam T - The SFTK object types
     */
    template <class T>
    class SFTKException : public std::exception
    {
    public:
        SFTKException(T *obj) : sftkObj(obj) {}
        /**
         * @brief # Address formatter
         *
         * This formatter function use 16 `*`s as address placeholder.
         *
         * When throwing an exception, Exceptions can use placeholder with this function
         * to fill the `what()` message. So the reported exception can tell where the crashed
         * SFTK object at.
         *
         * # Example
         *
         * ```c
         * const char *SomeException::what() const noexcept
         * {
         *     static char msg[] = "sftk::SomeClass 0x********_******** reported an exception.";
         *     SFTKException::formatAddress(msg, sizeof(msg));
         *     return const_cast<SomeClass *>(msg);
         * }
         * ```
         *
         * @param msg exception message
         * @param len message length
         */
        void formatAddress(char *msg, int len) const noexcept
        {
            auto ptr = reinterpret_cast<uintptr_t>(sftkObj);
            while (--len >= 0)
            {
                if (msg[len] == '*')
                {
                    auto bit = ptr-- & 0xf;
                    if (bit < 10)
                    {
                        bit += '0';
                    }
                    else
                    {
                        bit -= 10 - 'a';
                    }
                    msg[len] = bit;
                }
            }
        }

    private:
        T *sftkObj;
    };
};

#endif