gcc/libstdc++-v3/testsuite/ext/codecvt/char-1.cc

// { dg-require-iconv "UCS-2BE" }
// { dg-require-iconv "ISO-8859-15" }

// 2000-08-22 Benjamin Kosnik <bkoz@cygnus.com>

// Copyright (C) 2000-2022 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library 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, 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 General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3.  If not see
// <http://www.gnu.org/licenses/>.

// 22.2.1.5 - Template class codecvt [lib.locale.codecvt]
#include <locale>
#include <cstring>
#include <testsuite_hooks.h>
#include <ext/codecvt_specializations.h>

/*
> how do I check that these conversions are correct? 
Very easy.  Since all the characters are from ASCII you simply
zero-extend the values.

drepper$ echo 'black pearl jasmine tea' | od -t x1
0000000 62 6c 61 63 6b 20 70 65 61 72 6c 20 6a 61 73 6d
0000020 69 6e 65 20 74 65 61 0a

So the UCS-2 string is

0x0062, 0x006c, 0x0061, ...

You get the idea.  With iconv() you have to take care of the
byte-order, though.  UCS-2 can mean little- or big endian.  Looking at
your result

> $9 = 25856

it shows that the other byte-order is used (25856 == 0x6500).
*/

// Partial specialization using encoding_state.
// codecvt<unicode_t, char, encoding_state>
// UNICODE - UCS2 (big endian)
void test01()
{
  using namespace std;
  typedef codecvt_base::result			result;
  typedef unsigned short	       		int_type;
  typedef char					ext_type;
  typedef __gnu_cxx::encoding_state	       		state_type;
  typedef codecvt<int_type, ext_type, state_type>	unicode_codecvt;
  typedef char_traits<int_type>			int_traits;
  typedef char_traits<ext_type>			ext_traits;

  const ext_type* 	e_lit = "black pearl jasmine tea";
  int 			size = strlen(e_lit);

  char  i_lit_base[50] __attribute__((aligned(__alignof__(int_type)))) = 
  { 
    char(0x00), char(0x62), char(0x00), char(0x6c), char(0x00), char(0x61),
    char(0x00), char(0x63), char(0x00), char(0x6b), char(0x00), char(0x20),
    char(0x00), char(0x70), char(0x00), char(0x65), char(0x00), char(0x61),
    char(0x00), char(0x72), char(0x00), char(0x6c), char(0x00), char(0x20),
    char(0x00), char(0x6a), char(0x00), char(0x61), char(0x00), char(0x73),
    char(0x00), char(0x6d), char(0x00), char(0x69), char(0x00), char(0x6e),
    char(0x00), char(0x65), char(0x00), char(0x20), char(0x00), char(0x74),
    char(0x00), char(0x65), char(0x00), char(0x61), char(0x00), char(0xa0)
  };
  const int_type* 	i_lit = reinterpret_cast<int_type*>(i_lit_base);

  const ext_type*       efrom_next;
  const int_type*       ifrom_next;
  ext_type* 		e_arr = new ext_type[size + 1];
  ext_type*		eto_next;
  int_type* 		i_arr = new int_type[size + 1];
  int_type*		ito_next;

  // construct a locale object with the specialized facet.
  locale 		loc(locale::classic(), new unicode_codecvt);
  // sanity check the constructed locale has the specialized facet.
  VERIFY( has_facet<unicode_codecvt>(loc) );
  const unicode_codecvt& cvt = use_facet<unicode_codecvt>(loc); 

  // in
  //  unicode_codecvt::state_type state01("UCS-2BE", "ISO-8859-15", 0xfeff, 0);
  unicode_codecvt::state_type state01("UCS-2BE", "ISO-8859-15", 0, 0);

  // internal encoding is bigger because of bom
  result r1 = cvt.in(state01, e_lit, e_lit + size, efrom_next, 
		     i_arr, i_arr + size + 1, ito_next);
  VERIFY( r1 == codecvt_base::ok );
  VERIFY( !int_traits::compare(i_arr, i_lit, size) ); 
  VERIFY( efrom_next == e_lit + size );
  VERIFY( ito_next == i_arr + size );

  // out
  unicode_codecvt::state_type state02("UCS-2BE", "ISO-8859-15", 0, 0);
  result r2 = cvt.out(state02, i_lit, i_lit + size, ifrom_next, 
		       e_arr, e_arr + size, eto_next);
  VERIFY( r2 == codecvt_base::ok );
  VERIFY( !ext_traits::compare(e_arr, e_lit, size) ); 
  VERIFY( ifrom_next == i_lit + size );
  VERIFY( eto_next == e_arr + size );

  // unshift
  ext_traits::copy(e_arr, e_lit, size);
  unicode_codecvt::state_type state03("UCS-2BE", "ISO-8859-15", 0, 0);
  result r3 = cvt.unshift(state03, e_arr, e_arr + size, eto_next);
  VERIFY( r3 == codecvt_base::noconv );
  VERIFY( !ext_traits::compare(e_arr, e_lit, size) ); 
  VERIFY( eto_next == e_arr );

  int i = cvt.encoding();
  VERIFY( i == 2 ); // Target-dependent.

  VERIFY( !cvt.always_noconv() );

  unicode_codecvt::state_type state04("UCS-2BE", "ISO-8859-15", 0, 0);
  int j = cvt.length(state03, e_lit, e_lit + size, 5);
  VERIFY( j == 5 );

  int k = cvt.max_length();
  VERIFY( k == 1 );

  delete [] e_arr;
  delete [] i_arr;
}

int main ()
{
  test01();
  return 0;
}