/* Character set conversion with error handling.
   Copyright (C) 2001-2007, 2009-2021 Free Software Foundation, Inc.
   Written by Bruno Haible and Simon Josefsson.

   This file is free software: you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as
   published by the Free Software Foundation; either version 2.1 of the
   License, or (at your option) any later version.

   This file 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/>.  */

#ifndef _STRICONVEH_H
#define _STRICONVEH_H

#include <stddef.h>
#if HAVE_ICONV
#include <iconv.h>
#endif

#include "iconveh.h"


#ifdef __cplusplus
extern "C" {
#endif


#if HAVE_ICONV

/* A conversion descriptor for use by the iconveh functions.  */
typedef struct
  {
    /* Conversion descriptor from FROM_CODESET to TO_CODESET, or (iconv_t)(-1)
       if the system does not support a direct conversion from FROM_CODESET to
       TO_CODESET.  */
    iconv_t cd;
    /* Conversion descriptor from FROM_CODESET to UTF-8 (or (iconv_t)(-1) if
       FROM_CODESET is UTF-8).  */
    iconv_t cd1;
    /* Conversion descriptor from UTF-8 to TO_CODESET (or (iconv_t)(-1) if
       TO_CODESET is UTF-8).  */
    iconv_t cd2;
  }
  iconveh_t;

/* Open a conversion descriptor for use by the iconveh functions.
   If successful, fills *CDP and returns 0.  Upon failure, return -1 with errno
   set.  */
extern int
       iconveh_open (const char *to_codeset, const char *from_codeset,
                     iconveh_t *cdp);

/* Close a conversion descriptor created by iconveh_open().
   Return value: 0 if successful, otherwise -1 and errno set.  */
extern int
       iconveh_close (const iconveh_t *cd);

/* Convert an entire string from one encoding to another, using iconv.
   The original string is at [SRC,...,SRC+SRCLEN-1].
   CD points to the conversion descriptor from FROMCODE to TOCODE, created by
   the function iconveh_open().
   If OFFSETS is not NULL, it should point to an array of SRCLEN integers; this
   array is filled with offsets into the result, i.e. the character starting
   at SRC[i] corresponds to the character starting at (*RESULTP)[OFFSETS[i]],
   and other offsets are set to (size_t)(-1).
   *RESULTP and *LENGTH should initially be a scratch buffer and its size,
   or *RESULTP can initially be NULL.
   May erase the contents of the memory at *RESULTP.
   Return value: 0 if successful, otherwise -1 and errno set.
   If successful: The resulting string is stored in *RESULTP and its length
   in *LENGTHP.  *RESULTP is set to a freshly allocated memory block, or is
   unchanged if no dynamic memory allocation was necessary.  */
extern int
       mem_cd_iconveh (const char *src, size_t srclen,
                       const iconveh_t *cd,
                       enum iconv_ilseq_handler handler,
                       size_t *offsets,
                       char **resultp, size_t *lengthp);

/* Convert an entire string from one encoding to another, using iconv.
   The original string is the NUL-terminated string starting at SRC.
   CD points to the conversion descriptor from FROMCODE to TOCODE, created by
   the function iconveh_open().
   Both the "from" and the "to" encoding must use a single NUL byte at the end
   of the string (i.e. not UCS-2, UCS-4, UTF-16, UTF-32).
   Allocate a malloced memory block for the result.
   Return value: the freshly allocated resulting NUL-terminated string if
   successful, otherwise NULL and errno set.  */
extern char *
       str_cd_iconveh (const char *src,
                       const iconveh_t *cd,
                       enum iconv_ilseq_handler handler);

#endif

/* Convert an entire string from one encoding to another, using iconv.
   The original string is at [SRC,...,SRC+SRCLEN-1].
   If OFFSETS is not NULL, it should point to an array of SRCLEN integers; this
   array is filled with offsets into the result, i.e. the character starting
   at SRC[i] corresponds to the character starting at (*RESULTP)[OFFSETS[i]],
   and other offsets are set to (size_t)(-1).
   *RESULTP and *LENGTH should initially be a scratch buffer and its size,
   or *RESULTP can initially be NULL.
   May erase the contents of the memory at *RESULTP.
   Return value: 0 if successful, otherwise -1 and errno set.
   If successful: The resulting string is stored in *RESULTP and its length
   in *LENGTHP.  *RESULTP is set to a freshly allocated memory block, or is
   unchanged if no dynamic memory allocation was necessary.  */
extern int
       mem_iconveh (const char *src, size_t srclen,
                    const char *from_codeset, const char *to_codeset,
                    enum iconv_ilseq_handler handler,
                    size_t *offsets,
                    char **resultp, size_t *lengthp);

/* Convert an entire string from one encoding to another, using iconv.
   The original string is the NUL-terminated string starting at SRC.
   Both the "from" and the "to" encoding must use a single NUL byte at the
   end of the string (i.e. not UCS-2, UCS-4, UTF-16, UTF-32).
   Allocate a malloced memory block for the result.
   Return value: the freshly allocated resulting NUL-terminated string if
   successful, otherwise NULL and errno set.  */
extern char *
       str_iconveh (const char *src,
                    const char *from_codeset, const char *to_codeset,
                    enum iconv_ilseq_handler handler);


#ifdef __cplusplus
}
#endif


#endif /* _STRICONVEH_H */
