ModcompConversion.h

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// # ModCompConversion.h: A class with static functions to convert ModComp format
// # Copyright (C) 1998,1999,2001
// # Associated Universities, Inc. Washington DC, USA.
// #
// # This library is free software; you can redistribute it and/or modify it
// # under the terms of the GNU Library General Public License as published by
// # the Free Software Foundation; either version 2 of the License, or (at your
// # option) any later version.
// #
// # This library 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 Library General Public
// # License for more details.
// #
// # You should have received a copy of the GNU Library General Public License
// # along with this library; if not, write to the Free Software Foundation,
// # Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
// #
// # Correspondence concerning AIPS++ should be addressed as follows:
// #        Internet email: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef CASA_MODCOMPCONVERSION_H
#define CASA_MODCOMPCONVERSION_H
 
#include <casacore/casa/aips.h>
#include <casacore/casa/Utilities/Assert.h>
#include <casacore/casa/OS/CanonicalConversion.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// Define the canonical sizes of the built-in data types.
// These are the same for all machine architectures.
 
#define SIZE_MODCOMP_CHAR 1
#define SIZE_MODCOMP_UCHAR 1
#define SIZE_MODCOMP_SHORT 2
#define SIZE_MODCOMP_USHORT 2
#define SIZE_MODCOMP_INT 4
#define SIZE_MODCOMP_UINT 4
#define SIZE_MODCOMP_INT64 4
#define SIZE_MODCOMP_UINT64 4
#define SIZE_MODCOMP_FLOAT 4
#define SIZE_MODCOMP_DOUBLE 8
 
// Define for each data format if a conversion is needed from the ModComp
// format to the local format (or vice-versa).  This allows for optimizations
// in, for example, AipsIO.
 
// The ModComp format is ASCII for strings, a proprietary floating point format
// and 2-complement for integers (all most significant bit first) with the
// lengths as shown above.
 
// Change the definitions below if new architectures (whith different lengths
// for these integer types) are being used.
#define CONVERT_MODCOMP_CHAR 0
#define CONVERT_MODCOMP_UCHAR 0
// Conversion is needed for little endian architectures (like DEC and Intel),
// because the bytes have to be swapped (thus not for data with length 1).
#if defined(AIPS_LITTLE_ENDIAN)
#define CONVERT_MODCOMP_SHORT 1
#define CONVERT_MODCOMP_USHORT 1
#define CONVERT_MODCOMP_INT 1
#define CONVERT_MODCOMP_UINT 1
#define CONVERT_MODCOMP_INT64 1
#define CONVERT_MODCOMP_UINT64 1
#else
// Conversion is not needed for integers if the local lengths for Shorts and
// Ints is 2,4 respectively.
#define CONVERT_MODCOMP_SHORT 0
#define CONVERT_MODCOMP_USHORT 0
#define CONVERT_MODCOMP_INT 0
#define CONVERT_MODCOMP_UINT 0
#define CONVERT_MODCOMP_INT64 1
#define CONVERT_MODCOMP_UINT64 1
#endif
// Conversion is always needed for floating point data.
#define CONVERT_MODCOMP_FLOAT 1
#define CONVERT_MODCOMP_DOUBLE 1
 
// <summary>Static functions to convert Modcomp numeric formats</summary>
 
// <use visibility=export>
 
// <reviewed reviewer="" date="yyyy/mm/dd" tests="tModcompConversion" demos="">
// </reviewed>
 
// <synopsis>
// This class contains static toLocal functions to convert data from Modcomp
// format to local format and vice-versa.
//
// The functions work on both big-endian and little-endian machines. They
// convert between Modcomp 2-byte integers and Shorts (or uShorts) and Modcomp
// 4-byte integers and Ints (or uInts, Int64s or uInt64s).
//
// It is currently not possible to convert floating point numbers from local
// format to Modcomp. Attempting to do so will throw an exception (AipsError).
// </synopsis>
 
// <motivation>
// The VLA data is stored using Modcomp numeric data formats and needs to be
// converted to the local format to be manipulated.
// </motivation>
 
// <todo asof="$DATE$">
//  <li> Support conversion of floating point data to Modcomp format
//  <li> Support data type long double.
// </todo>
 
class ModcompConversion {
 public:
  // Convert one value from Modcomp format to local format.
  // The from and to buffer should not overlap.
  // <group>
  static size_t toLocal(Char& to, const void* from);
  static size_t toLocal(uChar& to, const void* from);
  static size_t toLocal(Short& to, const void* from);
  static size_t toLocal(uShort& to, const void* from);
  static size_t toLocal(Int& to, const void* from);
  static size_t toLocal(uInt& to, const void* from);
  static size_t toLocal(Int64& to, const void* from);
  static size_t toLocal(uInt64& to, const void* from);
  static size_t toLocal(Float& to, const void* from);
  static size_t toLocal(Double& to, const void* from);
  // </group>
 
  // Convert nr values from Modcomp format to local format.
  // The from and to buffer should not overlap.
  // <group>
  static size_t toLocal(Char* to, const void* from, size_t nr);
  static size_t toLocal(uChar* to, const void* from, size_t nr);
  static size_t toLocal(Short* to, const void* from, size_t nr);
  static size_t toLocal(uShort* to, const void* from, size_t nr);
  static size_t toLocal(Int* to, const void* from, size_t nr);
  static size_t toLocal(uInt* to, const void* from, size_t nr);
  static size_t toLocal(Int64* to, const void* from, size_t nr);
  static size_t toLocal(uInt64* to, const void* from, size_t nr);
  static size_t toLocal(Float* to, const void* from, size_t nr);
  static size_t toLocal(Double* to, const void* from, size_t nr);
  // </group>
 
  // Convert one value from local format to Modcomp format.  The from and to
  // buffer should not overlap. The floating point functions will throw
  // exceptions as they are not implemented yet.
  // <group>
  static size_t fromLocal(void* to, Char from);
  static size_t fromLocal(void* to, uChar from);
  static size_t fromLocal(void* to, Short from);
  static size_t fromLocal(void* to, uShort from);
  static size_t fromLocal(void* to, Int from);
  static size_t fromLocal(void* to, uInt from);
  static size_t fromLocal(void* to, Int64 from);
  static size_t fromLocal(void* to, uInt64 from);
  static size_t fromLocal(void* to, Float from);
  static size_t fromLocal(void* to, Double from);
  // </group>
 
  // Convert nr values from local format to Modcomp format.  The from and to
  // buffer should not overlap. The floating point functions will throw
  // exceptions as they are not implemented yet.
  // <group>
  static size_t fromLocal(void* to, const Char* from, size_t nr);
  static size_t fromLocal(void* to, const uChar* from, size_t nr);
  static size_t fromLocal(void* to, const Short* from, size_t nr);
  static size_t fromLocal(void* to, const uShort* from, size_t nr);
  static size_t fromLocal(void* to, const Int* from, size_t nr);
  static size_t fromLocal(void* to, const uInt* from, size_t nr);
  static size_t fromLocal(void* to, const Int64* from, size_t nr);
  static size_t fromLocal(void* to, const uInt64* from, size_t nr);
  static size_t fromLocal(void* to, const Float* from, size_t nr);
  static size_t fromLocal(void* to, const Double* from, size_t nr);
  // </group>
 
 private:
  // This class should not be constructed
  // (so declare the constructor private).
  ModcompConversion();
};
 
inline size_t ModcompConversion::toLocal(Char& to, const void* from) {
  return CanonicalConversion::toLocal(to, from);
}
 
inline size_t ModcompConversion::toLocal(uChar& to, const void* from) {
  return CanonicalConversion::toLocal(to, from);
}
 
inline size_t ModcompConversion::toLocal(Short& to, const void* from) {
  return CanonicalConversion::toLocal(to, from);
}
 
inline size_t ModcompConversion::toLocal(uShort& to, const void* from) {
  return CanonicalConversion::toLocal(to, from);
}
 
inline size_t ModcompConversion::toLocal(Int& to, const void* from) {
  return CanonicalConversion::toLocal(to, from);
}
 
inline size_t ModcompConversion::toLocal(uInt& to, const void* from) {
  return CanonicalConversion::toLocal(to, from);
}
 
inline size_t ModcompConversion::toLocal(Int64& to, const void* from) {
  Int tmp;
  size_t res = toLocal(tmp, from);
  to = tmp;
  return res;
}
 
inline size_t ModcompConversion::toLocal(uInt64& to, const void* from) {
  uInt tmp;
  size_t res = toLocal(tmp, from);
  to = tmp;
  return res;
}
 
inline size_t ModcompConversion::toLocal(Float& to, const void* from) {
  return ModcompConversion::toLocal(&to, from, 1u);
}
 
inline size_t ModcompConversion::toLocal(Double& to, const void* from) {
  return ModcompConversion::toLocal(&to, from, 1u);
}
 
inline size_t ModcompConversion::toLocal(Char* to, const void* from, size_t nr) {
  return CanonicalConversion::toLocalChar(to, from, nr);
}
 
inline size_t ModcompConversion::toLocal(uChar* to, const void* from, size_t nr) {
  return CanonicalConversion::toLocalUChar(to, from, nr);
}
 
inline size_t ModcompConversion::toLocal(Short* to, const void* from, size_t nr) {
  return CanonicalConversion::toLocalShort(to, from, nr);
}
 
inline size_t ModcompConversion::toLocal(uShort* to, const void* from, size_t nr) {
  return CanonicalConversion::toLocalUShort(to, from, nr);
}
 
inline size_t ModcompConversion::toLocal(Int* to, const void* from, size_t nr) {
  return CanonicalConversion::toLocalInt(to, from, nr);
}
 
inline size_t ModcompConversion::toLocal(uInt* to, const void* from, size_t nr) {
  return CanonicalConversion::toLocalUInt(to, from, nr);
}
 
inline size_t ModcompConversion::fromLocal(void* to, Char from) {
  return CanonicalConversion::fromLocal(to, from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, uChar from) {
  return CanonicalConversion::fromLocal(to, from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, Short from) {
  return CanonicalConversion::fromLocal(to, from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, uShort from) {
  return CanonicalConversion::fromLocal(to, from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, Int from) {
  return CanonicalConversion::fromLocal(to, from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, uInt from) {
  return CanonicalConversion::fromLocal(to, from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, Int64 from) {
  return CanonicalConversion::fromLocal(to, (Int)from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, uInt64 from) {
  return CanonicalConversion::fromLocal(to, (uInt)from);
}
 
inline size_t ModcompConversion::fromLocal(void* to, Float from) {
  return ModcompConversion::fromLocal(to, &from, 1u);
}
 
inline size_t ModcompConversion::fromLocal(void* to, Double from) {
  return ModcompConversion::fromLocal(to, &from, 1u);
}
 
inline size_t ModcompConversion::fromLocal(void* to, const Char* from, size_t nr) {
  return CanonicalConversion::fromLocalChar(to, from, nr);
}
 
inline size_t ModcompConversion::fromLocal(void* to, const uChar* from, size_t nr) {
  return CanonicalConversion::fromLocalUChar(to, from, nr);
}
 
inline size_t ModcompConversion::fromLocal(void* to, const Short* from, size_t nr) {
  return CanonicalConversion::fromLocalShort(to, from, nr);
}
 
inline size_t ModcompConversion::fromLocal(void* to, const uShort* from, size_t nr) {
  return CanonicalConversion::fromLocalUShort(to, from, nr);
}
 
inline size_t ModcompConversion::fromLocal(void* to, const Int* from, size_t nr) {
  return CanonicalConversion::fromLocalInt(to, from, nr);
}
 
inline size_t ModcompConversion::fromLocal(void* to, const uInt* from, size_t nr) {
  return CanonicalConversion::fromLocalUInt(to, from, nr);
}
 
}  // namespace casacore
 
#endif