path: root/iconvdata/iso-2022-jp.c

/* Conversion module for ISO-2022-JP.
   Copyright (C) 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.

   The GNU C 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.

   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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <gconv.h>
#include <stdint.h>
#include <string.h>
#include "jis0201.h"
#include "jis0208.h"
#include "jis0212.h"
#include "gb2312.h"
#include "ksc5601.h"

struct gap
{
  uint16_t start;
  uint16_t end;
  int32_t idx;
};

#include "iso8859-7jp.h"

/* This makes obvious what everybody knows: 0x1b is the Esc character.  */
#define ESC 0x1b

/* We provide our own initialization and destructor function.  */
#define DEFINE_INIT	0
#define DEFINE_FINI	0

/* Definitions used in the body of the `gconv' function.  */
#define FROM_LOOP		from_iso2022jp_loop
#define TO_LOOP			to_iso2022jp_loop
#define MIN_NEEDED_FROM		1
#define MAX_NEEDED_FROM		4
#define MIN_NEEDED_TO		4
#define MAX_NEEDED_TO		4
#define FROM_DIRECTION		(dir == from_iso2022jp)
#define PREPARE_LOOP \
  enum direction dir = ((struct iso2022jp_data *) step->data)->dir;	      \
  enum variant var = ((struct iso2022jp_data *) step->data)->var;	      \
  int save_set;								      \
  int *setp = &data->statep->count;
#define EXTRA_LOOP_ARGS		, var, setp


/* Direction of the transformation.  */
enum direction
{
  illegal_dir,
  to_iso2022jp,
  from_iso2022jp
};

/* We handle ISO-2022-jp and ISO-2022-JP-2 here.  */
enum variant
{
  illegal_var,
  iso2022jp,
  iso2022jp2
};


struct iso2022jp_data
{
  enum direction dir;
  enum variant var;
};


/* The COUNT element of the state keeps track of the currently selected
   character set.  The possible values are:  */
enum
{
  ASCII_set = 0,
  JISX0208_1978_set,
  JISX0208_1983_set,
  JISX0201_set,
  GB2312_set,
  KSC5601_set,
  JISX0212_set,
  ISO88591_set,
  ISO88597_set
};


int
gconv_init (struct gconv_step *step)
{
  /* Determine which direction.  */
  struct iso2022jp_data *new_data;
  enum direction dir = illegal_dir;
  enum variant var = illegal_var;
  int result;

  if (__strcasecmp (step->from_name, "ISO-2022-JP//") == 0)
    {
      dir = from_iso2022jp;
      var = iso2022jp;
    }
  else if (__strcasecmp (step->to_name, "ISO-2022-JP//") == 0)
    {
      dir = to_iso2022jp;
      var = iso2022jp;
    }
  else if (__strcasecmp (step->from_name, "ISO-2022-JP-2//") == 0)
    {
      dir = from_iso2022jp;
      var = iso2022jp2;
    }
  else if (__strcasecmp (step->to_name, "ISO-2022-JP-2//") == 0)
    {
      dir = to_iso2022jp;
      var = iso2022jp2;
    }

  result = GCONV_NOCONV;
  if (dir != illegal_dir
      && ((new_data
	   = (struct iso2022jp_data *) malloc (sizeof (struct iso2022jp_data)))
	  != NULL))
    {
      new_data->dir = dir;
      new_data->var = var;
      step->data = new_data;

      if (dir == from_iso2022jp)
	{
	  step->min_needed_from = MIN_NEEDED_FROM;
	  step->max_needed_from = MAX_NEEDED_FROM;
	  step->min_needed_to = MIN_NEEDED_TO;
	  step->max_needed_to = MIN_NEEDED_TO;
	}
      else
	{
	  step->min_needed_from = MIN_NEEDED_TO;
	  step->max_needed_from = MAX_NEEDED_TO;
	  step->min_needed_to = MIN_NEEDED_FROM;
	  step->max_needed_to = MIN_NEEDED_FROM + 2;
	}

      /* Yes, this is a stateful encoding.  */
      step->stateful = 1;

      result = GCONV_OK;
    }

  return result;
}


void
gconv_end (struct gconv_step *data)
{
  free (data->data);
}


/* Since this is a stateful encoding we have to provide code which resets
   the output state to the initial state.  This has to be done during the
   flushing.  */
#define EMIT_SHIFT_TO_INIT \
  if (data->statep->count != ASCII_set)					      \
    {									      \
      enum direction dir = ((struct iso2022jp_data *) step->data)->dir;	      \
									      \
      if (dir == from_iso2022jp)					      \
	/* It's easy, we don't have to emit anything, we just reset the	      \
	   state for the input.  */					      \
	data->statep->count = ASCII_set;				      \
      else								      \
	{								      \
	  char *outbuf = data->outbuf;					      \
	  								      \
	  /* We are not in the initial state.  To switch back we have	      \
	     to emit the sequence `Esc ( B'.  */			      \
	  if (outbuf + 3 > data->outbufend)				      \
	    /* We don't have enough room in the output buffer.  */	      \
	    status = GCONV_FULL_OUTPUT;					      \
	  else								      \
	    {								      \
	      /* Write out the shift sequence.  */			      \
	      *outbuf++ = ESC;						      \
	      *outbuf++ = '(';						      \
	      *outbuf++ = 'B';						      \
	      data->outbuf = outbuf;					      \
	      data->statep->count = ASCII_set;				      \
	    }								      \
	}								      \
    }


/* Since we might have to reset input pointer we must be able to save
   and retore the state.  */
#define SAVE_RESET_STATE(Save) \
  if (Save)								      \
    save_set = *setp;							      \
  else									      \
    *setp = save_set


/* First define the conversion function from ISO-2022-JP to UCS4.  */
#define MIN_NEEDED_INPUT	MIN_NEEDED_FROM
#define MAX_NEEDED_INPUT	MAX_NEEDED_FROM
#define MIN_NEEDED_OUTPUT	MIN_NEEDED_TO
#define LOOPFCT			FROM_LOOP
#define BODY \
  {									      \
    uint32_t ch = *inptr;						      \
									      \
    /* This is a 7bit character set, disallow all 8bit characters.  */	      \
    if (ch > 0x7f)							      \
      {									      \
	result = GCONV_ILLEGAL_INPUT;					      \
	break;								      \
      }									      \
									      \
    /* Recognize escape sequences.  */					      \
    if (ch == ESC)							      \
      {									      \
	/* We now must be prepared to read two to three more		      \
	   chracters.  If we have a match in the first character but	      \
	   then the input buffer ends we terminate with an error since	      \
	   we must not risk missing an escape sequence just because it	      \
	   is not entirely in the current input buffer.  */		      \
	if (inptr + 2 >= inend						      \
	    || (var == iso2022jp2 && inptr[1] == '$' && inptr[2] == '('	      \
		&& inptr + 3 >= inend))					      \
	  {								      \
	    /* Not enough input available.  */				      \
	    result = GCONV_EMPTY_INPUT;					      \
	    break;							      \
	  }								      \
									      \
	if (inptr[1] == '(')						      \
	  {								      \
	    if (inptr[2] == 'B')					      \
	      {								      \
		/* ASCII selected.  */					      \
		set = ASCII_set;					      \
		inptr += 3;						      \
		continue;						      \
	      }								      \
	    else if (inptr[2] == 'J')					      \
	      {								      \
		/* JIS X 0201 selected.  */				      \
		set = JISX0201_set;					      \
		inptr += 3;						      \
		continue;						      \
	      }								      \
	  }								      \
	else if (inptr[1] == '$')					      \
	  {								      \
	    if (inptr[2] == '@')					      \
	      {								      \
		/* JIS X 0208-1978 selected.  */			      \
		set = JISX0208_1978_set;				      \
		inptr += 3;						      \
		continue;						      \
	      }								      \
	    else if (inptr[2] == 'B')					      \
	      {								      \
		/* JIS X 0208-1983 selected.  */			      \
		set = JISX0208_1983_set;				      \
		inptr += 3;						      \
		continue;						      \
	      }								      \
	    else if (var == iso2022jp2)					      \
	      {								      \
		if (inptr[2] == 'A')					      \
		  {							      \
		    /* GB 2312-1980 selected.  */			      \
		    set = GB2312_set;					      \
		    inptr += 3;						      \
		    continue;						      \
		  }							      \
		else if (inptr[2] == '(')				      \
		  {							      \
		    if (inptr[3] == 'C')				      \
		      {							      \
			/* KSC 5601-1987 selected.  */			      \
			set = KSC5601_set;				      \
			inptr += 4;					      \
			continue;					      \
		      }							      \
		    else if (inptr[3] == 'D')				      \
		      {							      \
			/* JIS X 0212-1990 selected.  */		      \
			set = JISX0212_set;				      \
			inptr += 4;					      \
			continue;					      \
		      }							      \
		  }							      \
	      }								      \
	  }								      \
	else if (var == iso2022jp2 && inptr[1] == '.')			      \
	  {								      \
	    if (inptr[2] == 'A')					      \
	      {								      \
		/* ISO 8859-1-GR selected.  */				      \
		set = ISO88591_set;					      \
		inptr += 3;						      \
		continue;						      \
	      }								      \
	    else if (inptr[2] == 'F')					      \
	      {								      \
		/* ISO 8859-7-GR selected.  */				      \
		set = ISO88597_set;					      \
		inptr += 3;						      \
		continue;						      \
	      }								      \
	  }								      \
      }									      \
									      \
    if (set == ASCII_set						      \
	|| (var < ISO88591_set && (ch < 0x21 || ch == 0x7f))		      \
	|| (var >= ISO88591_set && ch < 0x20))				      \
      /* Almost done, just advance the input pointer.  */		      \
      ++inptr;								      \
    else if (set == JISX0201_set)					      \
      {									      \
	/* Use the JIS X 0201 table.  */				      \
	ch = jisx0201_to_ucs4 (ch + 0x80);				      \
	if (ch == UNKNOWN_10646_CHAR)					      \
	  {								      \
	    result = GCONV_ILLEGAL_INPUT;				      \
	    break;							      \
	  }								      \
	++inptr;							      \
      }									      \
    else if (set == ISO88591_set)					      \
      {									      \
	/* This is quite easy.  All characters are defined and the	      \
	   ISO 10646 value is computed by adding 0x80.  */		      \
	ch += 0x80;							      \
	++inptr;							      \
      }									      \
    else if (set == ISO88597_set)					      \
      {									      \
	/* We use the table from the ISO 8859-7 module.  */		      \
	ch = iso88597_to_ucs4[ch - 0x20];				      \
	if (ch == 0)							      \
	  {								      \
	    result = GCONV_ILLEGAL_INPUT;				      \
	    break;							      \
	  }								      \
	++inptr;							      \
      }									      \
    else								      \
      {									      \
	if (set == JISX0208_1978_set || set == JISX0208_1983_set)	      \
	  /* XXX I don't have the tables for these two old variants of	      \
	     JIS X 0208.  Therefore I'm using the tables for JIS X	      \
	     0208-1990.  If somebody has problems with this please	      \
	     provide the appropriate tables.  */			      \
	  ch = jisx0208_to_ucs4 (&inptr,				      \
				 NEED_LENGTH_TEST ? inend - inptr : 2, 0);    \
	else if (set == JISX0212_set)					      \
	  /* Use the JIS X 0212 table.  */				      \
	  ch = jisx0212_to_ucs4 (&inptr,				      \
				 NEED_LENGTH_TEST ? inend - inptr : 2, 0);    \
	else if (set == GB2312_set)					      \
	  /* Use the GB 2312 table.  */					      \
	  ch = gb2312_to_ucs4 (&inptr,					      \
			       NEED_LENGTH_TEST ? inend - inptr : 2, 0);      \
	else								      \
	  {								      \
	    assert (set == KSC5601_set);				      \
									      \
	    /* Use the KSC 5601 table.  */				      \
	    ch = ksc5601_to_ucs4 (&inptr,				      \
				  NEED_LENGTH_TEST ? inend - inptr : 2, 0);   \
	  }								      \
									      \
	if (NEED_LENGTH_TEST && ch == 0)				      \
	  {								      \
	    result = GCONV_EMPTY_INPUT;					      \
	    break;							      \
	  }								      \
	else if (ch == UNKNOWN_10646_CHAR)				      \
	  {								      \
	    result = GCONV_ILLEGAL_INPUT;				      \
	    break;							      \
	  }								      \
      }									      \
									      \
    *((uint32_t *) outptr)++ = ch;					      \
  }
#define EXTRA_LOOP_DECLS	, enum variant var, int *setp
#define INIT_PARAMS		int set = *setp
#define UPDATE_PARAMS		*setp = set
#include <iconv/loop.c>


/* Next, define the other direction.  */
#define MIN_NEEDED_INPUT	MIN_NEEDED_TO
#define MIN_NEEDED_OUTPUT	MIN_NEEDED_FROM
#define MAX_NEEDED_OUTPUT	(MAX_NEEDED_FROM + 2)
#define LOOPFCT			TO_LOOP
#define BODY \
  {									      \
    unsigned char ch;							      \
    size_t written = 0;							      \
									      \
    ch = *((uint32_t *) inptr);						      \
									      \
    /* First see whether we can write the character using the currently	      \
       selected character set.  */					      \
    if (set == ASCII_set						      \
	|| (ch >= 0x01 && ((set < ISO88591_set && (ch < 0x21 || ch == 0x7f))  \
			   || (set >= ISO88591_set && ch < 0x20))))	      \
      {									      \
	/* Please note that the NUL byte is *not* matched if we are not	      \
	   currently using the ASCII charset.  This is because we must	      \
	   switch to the initial state whenever a NUL byte is written.  */    \
	if (ch <= 0x7f)							      \
	  {								      \
	    *outptr++ = ch;						      \
	    written = 1;						      \
	  }								      \
      }									      \
    else if (set == JISX0201_set)					      \
      written = ucs4_to_jisx0201 (ch, outptr);				      \
    else if (set == ISO88591_set)					      \
      {									      \
	if (ch >= 0xa0 && ch <= 0xff)					      \
	  {								      \
	    *outptr++ = ch - 0x80;					      \
	    written = 1;						      \
	  }								      \
      }									      \
    else if (set == ISO88597_set)					      \
      {									      \
	const struct gap *rp = from_idx;				      \
									      \
	while (ch > rp->end)						      \
	  ++rp;								      \
	if (ch >= rp->start)						      \
	  {								      \
	    unsigned char res = iso88597_from_ucs4[ch + rp->idx];	      \
	    if (res != '\0')						      \
	      {								      \
		*outptr++ = res;					      \
		written = 1;						      \
	      }								      \
	  }								      \
      }									      \
    else								      \
      {									      \
	if (set == JISX0208_1978_set || set == JISX0208_1983_set)	      \
	  written = ucs4_to_jisx0208 (ch, outptr,			      \
				      (NEED_LENGTH_TEST			      \
				       ? outend - outptr : 2));		      \
	else if (set == JISX0212_set)					      \
	  written = ucs4_to_jisx0212 (ch, outptr,			      \
				      (NEED_LENGTH_TEST			      \
				       ? outend - outptr : 2));		      \
	else if (set == GB2312_set)					      \
	  written = ucs4_to_gb2312 (ch, outptr, (NEED_LENGTH_TEST	      \
						 ? outend - outptr : 2));     \
	else								      \
	  {								      \
	    assert (set == KSC5601_set);				      \
									      \
	    written = ucs4_to_ksc5601 (ch, outptr,			      \
				       (NEED_LENGTH_TEST		      \
					? outend - outptr : 2));	      \
	  }								      \
									      \
	if (NEED_LENGTH_TEST && written == 0)				      \
	  {								      \
	    result = GCONV_FULL_OUTPUT;					      \
	    break;							      \
	  }								      \
      }									      \
									      \
    if (written == UNKNOWN_10646_CHAR)					      \
      {									      \
	/* Either this is an unknown character or we have to switch	      \
	   the currently selected character set.  The character sets	      \
	   do not code entirely separate parts of ISO 10646 and		      \
	   therefore there is no single correct result.  If we choose	      \
	   the character set to use wrong we might be end up with	      \
	   using yet another character set for the next character	      \
	   though the current and the next could be encoded with one	      \
	   character set.  We leave this kind of optimization for	      \
	   later and now simply use a fixed order in which we test for	      \
	   availability  */						      \
									      \
	/* First test whether we have at least three more bytes for	      \
	   the escape sequence.  The two charsets which require four	      \
	   bytes will be handled later.  */				      \
	if (NEED_LENGTH_TEST && outptr + 3 > outend)			      \
	  {								      \
	    result = GCONV_FULL_OUTPUT;					      \
	    break;							      \
	  }								      \
									      \
	if (ch <= 0x7f)							      \
	  {								      \
	    /* We must encode using ASCII.  First write out the		      \
	       escape sequence.  */					      \
	    *outptr++ = ESC;						      \
	    *outptr++ = '(';						      \
	    *outptr++ = 'B';						      \
	    set = ASCII_set;						      \
									      \
	    if (NEED_LENGTH_TEST && outptr == outend)			      \
	      {								      \
		result = GCONV_FULL_OUTPUT;				      \
		break;							      \
	      }								      \
									      \
	    *outptr++ = ch;						      \
	  }								      \
	else if (ch >= 0xa0 && ch <= 0xff)				      \
	  {								      \
	    /* This character set is not available in ISO-2022-JP.  */	      \
	    if (var == iso2022jp)					      \
	      {								      \
		result = GCONV_ILLEGAL_INPUT;				      \
		break;							      \
	      }								      \
									      \
	    /* We must use the ISO 8859-1 upper half.   */		      \
	    *outptr++ = ESC;						      \
	    *outptr++ = '.';						      \
	    *outptr++ = 'A';						      \
	    set = ISO88591_set;						      \
									      \
	    if (NEED_LENGTH_TEST && outptr == outend)			      \
	      {								      \
		result = GCONV_FULL_OUTPUT;				      \
		break;							      \
	      }								      \
									      \
	    *outptr++ = ch - 0x80;					      \
	  }								      \
	else								      \
	  {								      \
	    /* Now it becomes difficult.  We must search the other	      \
	       character sets one by one and we cannot use simple	      \
	       arithmetic to determine whether the character can be	      \
	       encoded using this set.  */				      \
	    size_t written;						      \
	    unsigned char buf[2];					      \
									      \
	    written = ucs4_to_jisx0201 (ch, buf);			      \
	    if (written != UNKNOWN_10646_CHAR)				      \
	      {								      \
		/* We use JIS X 0201.  */				      \
		*outptr++ = ESC;					      \
		*outptr++ = '$';					      \
		*outptr++ = '@';					      \
		set = JISX0201_set;					      \
									      \
		if (NEED_LENGTH_TEST && outptr == outend)		      \
		  {							      \
		    result = GCONV_FULL_OUTPUT;				      \
		    break;						      \
		  }							      \
									      \
		*outptr++ = buf[0];					      \
	      }								      \
	    else							      \
	      {								      \
		written = ucs4_to_jisx0208 (ch, buf, 2);		      \
		if (written != UNKNOWN_10646_CHAR)			      \
		  {							      \
		    /* We use JIS X 0208.  */				      \
		    *outptr++ = ESC;					      \
		    *outptr++ = '$';					      \
		    *outptr++ = 'B';					      \
		    set = JISX0208_1983_set;				      \
									      \
		    if (NEED_LENGTH_TEST && outptr + 2 > outend)	      \
		      {							      \
			result = GCONV_FULL_OUTPUT;			      \
			break;						      \
		      }							      \
									      \
		    *outptr++ = buf[0];					      \
		    *outptr++ = buf[1];					      \
		  }							      \
		else if (var == iso2022jp)				      \
		  {							      \
		    /* We have no other choice.  */			      \
		    result = GCONV_ILLEGAL_INPUT;			      \
		    break;						      \
		  }							      \
		else							      \
		  {							      \
		    written = ucs4_to_jisx0208 (ch, buf, 2);		      \
		    if (written != UNKNOWN_10646_CHAR)			      \
		      {							      \
			/* We use JIS X 0212.  */			      \
			if (outptr + 4 > outend)			      \
			  {						      \
			    result = GCONV_FULL_OUTPUT;			      \
			    break;					      \
			  }						      \
			*outptr++ = ESC;				      \
			*outptr++ = '$';				      \
			*outptr++ = '(';				      \
			*outptr++ = 'D';				      \
			set = JISX0212_set;				      \
									      \
			if (NEED_LENGTH_TEST && outptr + 2 > outend)	      \
			  {						      \
			    result = GCONV_FULL_OUTPUT;			      \
			    break;					      \
			  }						      \
									      \
			*outptr++ = buf[0];				      \
			*outptr++ = buf[1];				      \
		      }							      \
		    else						      \
		      {							      \
			written = ucs4_to_gb2312 (ch, buf, 2);		      \
			if (written != UNKNOWN_10646_CHAR)		      \
			  {						      \
			    /* We use GB 2312.  */			      \
			    *outptr++ = ESC;				      \
			    *outptr++ = '$';				      \
			    *outptr++ = 'A';				      \
			    set = GB2312_set;				      \
									      \
			    if (NEED_LENGTH_TEST && outptr + 2 > outend)      \
			      {						      \
				result = GCONV_FULL_OUTPUT;		      \
				break;					      \
			      }						      \
									      \
			    *outptr++ = buf[0];				      \
			    *outptr++ = buf[1];				      \
			  }						      \
			else						      \
			  {						      \
			    written = ucs4_to_ksc5601 (ch, buf, 2);	      \
			    if (written != UNKNOWN_10646_CHAR)		      \
			      {						      \
				/* We use KSC 5601.  */			      \
				if (outptr + 4 > outend)		      \
				  {					      \
				    result = GCONV_FULL_OUTPUT;		      \
				    break;				      \
				  }					      \
				*outptr++ = ESC;			      \
				*outptr++ = '$';			      \
				*outptr++ = '(';			      \
				*outptr++ = 'C';			      \
				set = KSC5601_set;			      \
									      \
				if (NEED_LENGTH_TEST			      \
				    && outptr + 2 > outend)		      \
				  {					      \
				    result = GCONV_FULL_OUTPUT;		      \
				    break;				      \
				  }					      \
									      \
				*outptr++ = buf[0];			      \
				*outptr++ = buf[1];			      \
			      }						      \
			    else					      \
			      {						      \
				result = GCONV_ILLEGAL_INPUT;		      \
				break;					      \
			      }						      \
			  }						      \
		      }							      \
		  }							      \
	      }								      \
	  }								      \
      }									      \
									      \
    /* Now that we wrote the output increment the input pointer.  */	      \
    inptr += 4;								      \
  }
#define EXTRA_LOOP_DECLS	, enum variant var, int *setp
#define INIT_PARAMS		int set = *setp
#define UPDATE_PARAMS		*setp = set
#include <iconv/loop.c>


/* Now define the toplevel functions.  */
#include <iconv/skeleton.c>