Exception.cpp

/*
 * Copyright (C) 2021 CERN
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
 *    appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 *
 * Created on: 2021-11-22
 *     Author: Michal Mysior <mmysior> <michal.mysior@cern.ch>
 *
 */
 
#include "Exception.hpp"
 
#include <cerrno>
#include <cstring>
#include <system_error>
 
namespace smc {
 
Exception::Exception(std::error_code ev) : m_errorCode{ev} {}
 
Exception::Exception(std::error_code ev, const std::string &what) :
    m_errorCode{ev},
    m_what(what)
{}
 
const char *Exception::what() const noexcept
{
    if (m_what.empty())
        m_what = m_errorCode.message();
    return m_what.c_str();
}
 
struct ErrorCategory : std::error_category
{
    const char *name() const noexcept override;
    std::string message(int ev) const override;
};
 
const char *ErrorCategory::name() const noexcept
{
    return "MotionControllerError";
}
 
std::string ErrorCategory::message(int ev) const
{
    if (ev == 0)
        return "Ok";
    else if (ev < 1000)
        return ::strerror(ev);
 
    switch (static_cast<ErrorCode>(ev))
    {
    case ErrorCode::IncompatibleUnits: return "Cannot convert units";
    case ErrorCode::InternalError: return "Internal error";
    default: return "Unknown error";
    }
}
 
const ErrorCategory errorCategory{};
 
std::error_code make_error_code(ErrorCode e)
{
    return {static_cast<int>(e), errorCategory};
}
 
Exception make_errno_exception(std::error_code ev)
{
    return Exception(ev, ::strerror(errno));
}
 
} /* namespace smc */