/* Conversion from UTF-8 to legacy encodings.
   Copyright (C) 2002, 2006-2007, 2009-2018 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or
   modify it under the terms of either:

     * the GNU Lesser General Public License as published by the Free
       Software Foundation; either version 3 of the License, or (at your
       option) any later version.

   or

     * the GNU General Public License as published by the Free
       Software Foundation; either version 2 of the License, or (at your
       option) any later version.

   or both in parallel, as here.
   This program 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

/* Written by Bruno Haible <bruno@clisp.org>.  */

#include <config.h>

/* Specification.  */
#include "uniconv.h"

#include <errno.h>
#include <stdlib.h>
#include <string.h>

#include "c-strcaseeq.h"
#include "striconveha.h"
#include "unistr.h"

char *
u8_strconv_to_encoding (const uint8_t *string,
                        const char *tocode,
                        enum iconv_ilseq_handler handler)
{
  char *result;
  size_t length;

  if (STRCASEEQ (tocode, "UTF-8", 'U','T','F','-','8',0,0,0,0))
    {
      /* Conversion from UTF-8 to UTF-8.  No need to go through iconv().  */
      length = u8_strlen (string) + 1;
      if (u8_check (string, length))
        {
          errno = EILSEQ;
          return NULL;
        }
      result = (char *) malloc (length);
      if (result == NULL)
        {
          errno = ENOMEM;
          return NULL;
        }
      memcpy (result, (const char *) string, length);
      return result;
    }
  else
    {
      result = NULL;
      length = 0;
      if (mem_iconveha ((const char *) string, u8_strlen (string) + 1,
                        "UTF-8", tocode,
                        handler == iconveh_question_mark, handler,
                        NULL, &result, &length) < 0)
        return NULL;
      /* Verify the result has exactly one NUL byte, at the end.  */
      if (!(length > 0 && result[length-1] == '\0'
            && strlen (result) == length-1))
        {
          free (result);
          errno = EILSEQ;
          return NULL;
        }
      return result;
    }
}
