/* Transliteration using the locale's data.

   Copyright (C) 2000-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Ulrich Drepper <drepper@cygnus.com>, 2000.

   The GNU C Library 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.

   The GNU C 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

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <assert.h>

#include <dlfcn.h>

#include <search.h>

#include <stdint.h>

#include <string.h>

#include <stdlib.h>

#include <libc-lock.h>

#include "gconv_int.h"

#include "../locale/localeinfo.h"

int

__gconv_transliterate (struct __gconv_step *step,

		       struct __gconv_step_data *step_data,

		       const unsigned char *inbufstart,

		       const unsigned char **inbufp,

		       const unsigned char *inbufend,

		       unsigned char **outbufstart, size_t *irreversible)

{

  /* Find out about the locale's transliteration.  */

  uint_fast32_t size;

  const uint32_t *from_idx;

  const uint32_t *from_tbl;

  const uint32_t *to_idx;

  const uint32_t *to_tbl;

  const uint32_t *winbuf;

  const uint32_t *winbufend;

  uint_fast32_t low;

  uint_fast32_t high;

  /* The input buffer.  There are actually 4-byte values.  */

  winbuf = (const uint32_t *) *inbufp;

  winbufend = (const uint32_t *) inbufend;

  __gconv_fct fct = step->__fct;

#ifdef PTR_DEMANGLE

  if (step->__shlib_handle != NULL)

    PTR_DEMANGLE (fct);

#endif

  /* If there is no transliteration information in the locale don't do

     anything and return the error.  */

  size = _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_TRANSLIT_TAB_SIZE);

  if (size == 0)

    goto no_rules;

  /* Get the rest of the values.  */

  from_idx =

    (const uint32_t *) _NL_CURRENT (LC_CTYPE, _NL_CTYPE_TRANSLIT_FROM_IDX);

  from_tbl =

    (const uint32_t *) _NL_CURRENT (LC_CTYPE, _NL_CTYPE_TRANSLIT_FROM_TBL);

  to_idx =

    (const uint32_t *) _NL_CURRENT (LC_CTYPE, _NL_CTYPE_TRANSLIT_TO_IDX);

  to_tbl =

    (const uint32_t *) _NL_CURRENT (LC_CTYPE, _NL_CTYPE_TRANSLIT_TO_TBL);

  /* Test whether there is enough input.  */

  if (winbuf + 1 > winbufend)

    return (winbuf == winbufend

	    ? __GCONV_EMPTY_INPUT : __GCONV_INCOMPLETE_INPUT);

  /* The array starting at FROM_IDX contains indeces to the string table

     in FROM_TBL.  The indeces are sorted wrt to the strings.  I.e., we

     are doing binary search.  */

  low = 0;

  high = size;

  while (low < high)

    {

      uint_fast32_t med = (low + high) / 2;

      uint32_t idx;

      int cnt;

      /* Compare the string at this index with the string at the current

	 position in the input buffer.  */

      idx = from_idx[med];

      cnt = 0;

      do

	{

	  if (from_tbl[idx + cnt] != winbuf[cnt])

	    /* Does not match.  */

	    break;

	  ++cnt;

	}

      while (from_tbl[idx + cnt] != L'\0' && winbuf + cnt < winbufend);

      if (cnt > 0 && from_tbl[idx + cnt] == L'\0')

	{

	  /* Found a matching input sequence.  Now try to convert the

	     possible replacements.  */

	  uint32_t idx2 = to_idx[med];

	  do

	    {

	      /* Determine length of replacement.  */

	      uint_fast32_t len = 0;

	      int res;

	      const unsigned char *toinptr;

	      unsigned char *outptr;

	      while (to_tbl[idx2 + len] != L'\0')

		++len;

	      /* Try this input text.  */

	      toinptr = (const unsigned char *) &to_tbl[idx2];

	      outptr = *outbufstart;

	      res = DL_CALL_FCT (fct,

				 (step, step_data, &toinptr,

				  (const unsigned char *) &to_tbl[idx2 + len],

				  &outptr, NULL, 0, 0));

	      if (res != __GCONV_ILLEGAL_INPUT)

		{

		  /* If the conversion succeeds we have to increment the

		     input buffer.  */

		  if (res == __GCONV_EMPTY_INPUT)

		    {

		      *inbufp += cnt * sizeof (uint32_t);

		      ++*irreversible;

		      res = __GCONV_OK;

		    }

		  /* Do not increment the output pointer if we could not

		     store the entire output. */

		  if (res != __GCONV_FULL_OUTPUT)

		    *outbufstart = outptr;

		  return res;

		}

	      /* Next replacement.  */

	      idx2 += len + 1;

	    }

	  while (to_tbl[idx2] != L'\0');

	  /* Nothing found, continue searching.  */

	}

      else if (cnt > 0)

	/* This means that the input buffer contents matches a prefix of

	   an entry.  Since we cannot match it unless we get more input,

	   we will tell the caller about it.  */

	return __GCONV_INCOMPLETE_INPUT;

      if (winbuf + cnt >= winbufend || from_tbl[idx + cnt] < winbuf[cnt])

	low = med + 1;

      else

	high = med;

    }

 no_rules:

  /* Maybe the character is supposed to be ignored.  */

  if (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_TRANSLIT_IGNORE_LEN) != 0)

    {

      int n = _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_TRANSLIT_IGNORE_LEN);

      const uint32_t *ranges =

	(const uint32_t *) _NL_CURRENT (LC_CTYPE, _NL_CTYPE_TRANSLIT_IGNORE);

      const uint32_t wc = *(const uint32_t *) (*inbufp);

      int i;

      /* Test whether there is enough input.  */

      if (winbuf + 1 > winbufend)

	return (winbuf == winbufend

		? __GCONV_EMPTY_INPUT : __GCONV_INCOMPLETE_INPUT);

      for (i = 0; i < n; ranges += 3, ++i)

	if (ranges[0] <= wc && wc <= ranges[1]

	    && (wc - ranges[0]) % ranges[2] == 0)

	  {

	    /* Matches the range.  Ignore it.  */

	    *inbufp += 4;

	    ++*irreversible;

	    return __GCONV_OK;

	  }

	else if (wc < ranges[0])

	  /* There cannot be any other matching range since they are

             sorted.  */

	  break;

    }

  /* One last chance: use the default replacement.  */

  if (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_TRANSLIT_DEFAULT_MISSING_LEN) != 0)

    {

      const uint32_t *default_missing = (const uint32_t *)

	_NL_CURRENT (LC_CTYPE, _NL_CTYPE_TRANSLIT_DEFAULT_MISSING);

      const unsigned char *toinptr = (const unsigned char *) default_missing;

      uint32_t len = _NL_CURRENT_WORD (LC_CTYPE,

				       _NL_CTYPE_TRANSLIT_DEFAULT_MISSING_LEN);

      unsigned char *outptr;

      int res;

      /* Test whether there is enough input.  */

      if (winbuf + 1 > winbufend)

	return (winbuf == winbufend

		? __GCONV_EMPTY_INPUT : __GCONV_INCOMPLETE_INPUT);

      outptr = *outbufstart;

      res = DL_CALL_FCT (fct,

			 (step, step_data, &toinptr,

			  (const unsigned char *) (default_missing + len),

			  &outptr, NULL, 0, 0));

      if (res != __GCONV_ILLEGAL_INPUT)

	{

	  /* If the conversion succeeds we have to increment the

	     input buffer.  */

	  if (res == __GCONV_EMPTY_INPUT)

	    {

	      /* This worked but is not reversible.  */

	      ++*irreversible;

	      *inbufp += 4;

	      res = __GCONV_OK;

	    }

	  *outbufstart = outptr;

	  return res;

	}

    }

  /* Haven't found a match.  */

  return __GCONV_ILLEGAL_INPUT;

}

libc_hidden_def (__gconv_transliterate)