binVector.hpp

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/** \file binVector.hpp
 * \author Jared R. Males
 * \brief A utility to read/write vectors of data from/to a binary file.
 * \ingroup utils_files
 */
 
//***********************************************************************//
// Copyright 2015, 2016, 2017 Jared R. Males (jaredmales@gmail.com)
//
// This file is part of mxlib.
//
// mxlib 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.
//
// mxlib 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 mxlib.  If not, see <http://www.gnu.org/licenses/>.
//***********************************************************************//
 
#ifndef binVector_hpp
#define binVector_hpp
 
#include <vector>
#include <complex>
#include <cstdint>
 
#include "../mxlib.hpp"
 
namespace mx
{
namespace ioutils
{
 
/** \defgroup binvector binVector Binary File Format
 * \ingroup ioutils
 * \brief A simple binary file format for storing vectors of data on disk.
 *
 * The binVector file format is very simple: the first 8 bytes contain a unit64_t integer which specifies
 * the type of the data. The second 8 bytes contain a uint64_t integer which specifies the length L of the data vector.
 * The remaining L*sizeof(dataT) bytes contain the data.
 *
 * The suggested extension for BinVector files is ".binv".
 *
 *
 */
 
/// The type used for binVector sizes.
/** \ingroup binVector
 */
typedef uint64_t binVSizeT;
 
/// The type of binVector type codes.
/** \ingroup binvector
 */
typedef uint64_t binVTypeT;
 
/// Namespace fo the bin-vector type-codes.
/** \ingroup binvector
 */
namespace binVTypes
{
 
/// The pre-defined type codes for binVector.
/** \ingroup binvector
 */
enum : binVTypeT
{
    Bool = 0,
    SChar = 1,
    UChar = 2,
    Char = 3,
    WChar = 4,
    Char16 = 5,
    Char32 = 6,
    Int = 7,
    UInt = 8,
    SInt = 9,
    SUInt = 10,
    LInt = 11,
    LUInt = 12,
    LLInt = 13,
    LLUInt = 14,
    Float = 15,
    Double = 16,
    LDouble = 17,
    Quad = 18,
    CFloat = 19,
    CDouble = 20,
};
 
} // namespace binVTypes
 
/// Get the integer type code corresponding to the type.
/**
 * \returns an integer which uniquely identifies the type.
 *
 * \tparam dataT is the type
 *
 * \ingroup binvector
 */
template <typename dataT>
binVTypeT binVectorTypeCode();
 
template <>
binVTypeT binVectorTypeCode<bool>()
{
    return binVTypes::Bool;
}
 
template <>
binVTypeT binVectorTypeCode<signed char>()
{
    return binVTypes::SChar;
}
 
template <>
binVTypeT binVectorTypeCode<unsigned char>()
{
    return binVTypes::UChar;
}
 
template <>
binVTypeT binVectorTypeCode<char>()
{
    return binVTypes::Char;
}
 
template <>
binVTypeT binVectorTypeCode<wchar_t>()
{
    return binVTypes::WChar;
}
 
template <>
binVTypeT binVectorTypeCode<char16_t>()
{
    return binVTypes::Char16;
}
 
template <>
binVTypeT binVectorTypeCode<char32_t>()
{
    return binVTypes::Char32;
}
 
template <>
binVTypeT binVectorTypeCode<int>()
{
    return binVTypes::Int;
}
 
template <>
binVTypeT binVectorTypeCode<unsigned int>()
{
    return binVTypes::UInt;
}
 
template <>
binVTypeT binVectorTypeCode<short int>()
{
    return binVTypes::SInt;
}
 
template <>
binVTypeT binVectorTypeCode<short unsigned int>()
{
    return binVTypes::SUInt;
}
 
template <>
binVTypeT binVectorTypeCode<long int>()
{
    return binVTypes::LInt;
}
 
template <>
binVTypeT binVectorTypeCode<long unsigned int>()
{
    return binVTypes::LUInt;
}
 
template <>
binVTypeT binVectorTypeCode<long long int>()
{
    return binVTypes::LLInt;
}
 
template <>
binVTypeT binVectorTypeCode<long long unsigned int>()
{
    return binVTypes::LLUInt;
}
 
template <>
binVTypeT binVectorTypeCode<float>()
{
    return binVTypes::Float;
}
 
template <>
binVTypeT binVectorTypeCode<double>()
{
    return binVTypes::Double;
}
 
template <>
binVTypeT binVectorTypeCode<long double>()
{
    return binVTypes::LDouble;
}
 
template <>
binVTypeT binVectorTypeCode<std::complex<float>>()
{
    return binVTypes::CFloat;
}
 
template <>
binVTypeT binVectorTypeCode<std::complex<double>>()
{
    return binVTypes::CDouble;
}
 
/// Read a BinVector file from disk.
/**
 * \note dataT must match what was stored in the file.
 *
 * \returns 0 on success.
 * \returns -1 if an error occurs.
 *
 * \ingroup binvector
 */
template <typename dataT>
int readBinVector( std::vector<dataT> &vec, ///< [out] vec is a vector which will be resized and populated.
                   const std::string &fname ///<  [in] fname is the name (full-path) of the file.
)
{
    FILE *fin;
    binVTypeT typecode;
    binVSizeT sz;
    size_t nrd;
 
    fin = fopen( fname.c_str(), "r" );
    if( fin == 0 )
    {
        internal::mxlib_error_report( errno2error_t( errno ), "Error from fopen [" + fname + "]" );
        return -1;
    }
 
    errno = 0;
    nrd = fread( &typecode, sizeof( binVTypeT ), 1, fin );
 
    if( nrd != 1 )
    {
        // Have to handle case where EOF reached but no error.
        if( errno != 0 )
        {
            internal::mxlib_error_report( errno2error_t( errno ), "Error reading data size [" + fname + "]" );
        }
        else
        {
            internal::mxlib_error_report( error_t::filererr,
                                          "Error reading data size, did not read enough bytes. [" + fname + "]" );
        }
        fclose( fin );
        return -1;
    }
 
    if( typecode != binVectorTypeCode<dataT>() )
    {
        internal::mxlib_error_report( error_t::sizeerr,
                                      "Mismatch between type dataT and type in file [" + fname + "]" );
        fclose( fin );
        return -1;
    }
 
    errno = 0;
    nrd = fread( &sz, sizeof( binVSizeT ), 1, fin );
 
    if( nrd != 1 )
    {
        // Have to handle case where EOF reached but no error.
        if( errno != 0 )
        {
            internal::mxlib_error_report( errno2error_t( errno ), "Error reading vector size [" + fname + "]" );
        }
        else
        {
            internal::mxlib_error_report( error_t::filererr,
                                          "Error reading vector size, did not read enough bytes [" + fname + "]" );
        }
        fclose( fin );
        return -1;
    }
 
    vec.resize( sz );
 
    errno = 0;
    nrd = fread( vec.data(), sizeof( dataT ), sz, fin );
 
    if( nrd != sz )
    {
        // Have to handle case where EOF reached but no error.
        if( errno != 0 )
        {
            internal::mxlib_error_report( errno2error_t( errno ), "Error reading data [" + fname + "]" );
        }
        else
        {
            internal::mxlib_error_report( error_t::filererr, "Did not read enough data [" + fname + "]" );
        }
        fclose( fin );
        return -1;
    }
 
    fclose( fin );
 
    return 0;
}
 
/// Write a BinVector file to disk.
/**
 *
 * \returns 0 on success.
 * \returns -1 if an error occurs.
 *
 * \ingroup binvector
 */
template <typename dataT>
int writeBinVector( const std::string &fname, ///< [in] fname is the name (full-path) of the file.
                    std::vector<dataT> &vec   ///< [in] vec is the vector which will be written to disk.
)
{
 
    FILE *fout;
    size_t nwr;
    binVTypeT typecode = binVectorTypeCode<dataT>();
    binVSizeT sz = vec.size();
 
    fout = fopen( fname.c_str(), "wb" );
    if( fout == 0 )
    {
        internal::mxlib_error_report( errno2error_t( errno ), "Error from fopen [" + fname + "]" );
        return -1;
    }
 
    nwr = fwrite( &typecode, sizeof( binVTypeT ), 1, fout );
    if( nwr != 1 )
    {
        internal::mxlib_error_report( errno2error_t( errno ), "Error writing typecode [" + fname + "]" );
        fclose( fout );
        return -1;
    }
 
    nwr = fwrite( &sz, sizeof( binVSizeT ), 1, fout );
    if( nwr != 1 )
    {
        internal::mxlib_error_report( errno2error_t( errno ), "Error writing vector size [" + fname + "]" );
        fclose( fout );
        return -1;
    }
 
    nwr = fwrite( vec.data(), sizeof( dataT ), vec.size(), fout );
    if( nwr != sz )
    {
        internal::mxlib_error_report( errno2error_t( errno ), "Error writing data [" + fname + "]" );
        fclose( fout );
        return -1;
    }
 
    fclose( fout );
 
    return 0;
}
 
} // namespace ioutils
} // namespace mx
 
#endif // binVector_hpp