opm-common/opm/io/eclipse/PaddedOutputString.hpp
Bård Skaflestad 725ac521ba Promote 'CharArrayNullTerm' to EclIO::PaddedOutputString
Space-padded vectors of N (usually 8) characters is the typical
representation of character data in ECLIPSE output files.  Support
this type natively in the ECLIPSE IO library.
2019-06-03 14:19:48 +02:00

104 lines
3.2 KiB
C++

/*
Copyright (c) 2018 Statoil ASA
This file is part of the Open Porous Media project (OPM).
OPM is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OPM is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with OPM. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef OPM_PADDEDOUTPUTSTRING_HEADER_HPP
#define OPM_PADDEDOUTPUTSTRING_HEADER_HPP
#include <algorithm>
#include <array>
#include <cstring>
#include <cstddef>
#include <string>
namespace Opm { namespace EclIO {
/// Null-terminated, left adjusted, space padded array of N characters.
///
/// Simple container of character data. Exists solely for purpose of
/// outputting std::string (or types convertible to std::string) as
/// Fortran-style \code character (len=N) \endcode values.
///
/// \tparam N Number of characters.
template <std::size_t N>
class PaddedOutputString
{
public:
PaddedOutputString()
{
this->clear();
}
explicit PaddedOutputString(const std::string& s)
: PaddedOutputString()
{
this->copy_in(s.c_str(), s.size());
}
~PaddedOutputString() = default;
PaddedOutputString(const PaddedOutputString& rhs) = default;
PaddedOutputString(PaddedOutputString&& rhs) = default;
PaddedOutputString& operator=(const PaddedOutputString& rhs) = default;
PaddedOutputString& operator=(PaddedOutputString&& rhs) = default;
/// Assign from \code std::string \endcode.
PaddedOutputString& operator=(const std::string& s)
{
this->clear();
this->copy_in(s.data(), s.size());
return *this;
}
const char* c_str() const
{
return this->s_.data();
}
private:
enum : typename std::array<char, N + 1>::size_type { NChar = N };
std::array<char, NChar + 1> s_;
/// Clear contents of internal array (fill with ' ').
void clear()
{
this->s_.fill(' ');
this->s_[NChar] = '\0';
}
/// Assign new value to internal array (left adjusted, space padded
/// and null-terminated).
void copy_in(const char* s,
const typename std::array<char, NChar + 1>::size_type len)
{
const auto ncpy = std::min(len, static_cast<decltype(len)>(NChar));
// Note: Not strcpy() or strncpy() here. The former has no bounds
// checking, the latter writes a null-terminator at position 'ncpy'
// (s_[ncpy]) which violates the post condition if ncpy < NChar.
std::memcpy(this->s_.data(), s,
ncpy * sizeof *this->s_.data());
}
};
}} // Opm::EclIO
#endif // OPM_PADDEDOUTPUTSTRING_HEADER_HPP