glibc/iconvdata/iso-2022-cn.c

399 lines
13 KiB
C
Raw Normal View History

/* Conversion module for ISO-2022-CN.
Copyright (C) 1999 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
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 "gb2312.h"
#include "cns11643l1.h"
#include "cns11643l2.h"
#include <assert.h>
/* This makes obvious what everybody knows: 0x1b is the Esc character. */
#define ESC 0x1b
/* We have single-byte shift-in and shift-out sequences, and the single
shift sequence SS2 which replaces the SS2 designation for the next
two bytes. */
#define SI 0x0f
#define SO 0x0e
#define SS2_0 ESC
#define SS2_1 0x4e
/* Definitions used in the body of the `gconv' function. */
#define CHARSET_NAME "ISO-2022-CN//"
#define DEFINE_INIT 1
#define DEFINE_FINI 1
#define FROM_LOOP from_iso2022cn_loop
#define TO_LOOP to_iso2022cn_loop
#define MIN_NEEDED_FROM 1
#define MAX_NEEDED_FROM 4
#define MIN_NEEDED_TO 4
#define MAX_NEEDED_TO 4
#define PREPARE_LOOP \
int save_set; \
int *setp = &data->__statep->count;
#define EXTRA_LOOP_ARGS , setp
/* The COUNT element of the state keeps track of the currently selected
character set. The possible values are: */
enum
{
ASCII_set = 0,
GB2312_set,
CNS11643_1_set,
CNS11643_2_set,
CURRENT_MASK = 3,
GB2312_ann = 4,
CNS11643_1_ann = 8,
CNS11643_2_ann = 16
};
/* 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) \
{ \
if (FROM_DIRECTION) \
/* It's easy, we don't have to emit anything, we just reset the \
state for the input. */ \
data->__statep->count = ASCII_set; \
else \
{ \
unsigned char *outbuf = data->__outbuf; \
\
/* We are not in the initial state. To switch back we have \
to emit `SI'. */ \
if (outbuf == data->__outbufend) \
/* We don't have enough room in the output buffer. */ \
status = __GCONV_FULL_OUTPUT; \
else \
{ \
/* Write out the shift sequence. */ \
*outbuf++ = SI; \
if (data->__is_last) \
*written += 1; \
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-CN 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) \
{ \
/* There are two kinds of escape sequences we have to handle: \
- those announcing the use of GB and CNS characters on the \
line; we can simply ignore them \
- the initial byte of the SS2 sequence. \
*/ \
if (NEED_LENGTH_TEST \
&& (inptr + 1 > inend \
|| (inptr[1] == '$' \
&& (inptr + 2 > inend \
|| (inptr[2] == ')' && inptr + 3 > inend) \
|| (inptr[2] == '*' && inptr + 3 > inend))) \
|| (inptr[1] == SS2_1 && inptr + 3 > inend))) \
{ \
result = __GCONV_EMPTY_INPUT; \
break; \
} \
if (inptr[1] == '$' \
&& ((inptr[2] == ')' && (inptr[3] == 'A' || inptr[3] == 'G')) \
|| (inptr[2] == '*' && inptr[3] == 'H'))) \
{ \
/* OK, we accept those character sets. */ \
if (inptr[3] == 'A') \
ann = GB2312_ann; \
else if (inptr[3] == 'G') \
ann = CNS11643_1_ann; \
inptr += 4; \
continue; \
} \
} \
else if (ch == SO) \
{ \
/* Switch to use GB2312 or CNS 11643 plane 1, depending on which \
S0 designation came last. The only problem is what to do with \
faulty input files where no designator came. \
XXX For now I'll default to use GB2312. If this is not the \
best behaviour (e.g., we should flag an error) let me know. */ \
++inptr; \
set = ann == CNS11643_1_ann ? CNS11643_1_set : GB2312_set; \
continue; \
} \
else if (ch == SI) \
{ \
/* Switch to use ASCII. */ \
++inptr; \
set = ASCII_set; \
continue; \
} \
\
if (ch == ESC && inptr[1] == SS2_1) \
{ \
/* This is a character from CNS 11643 plane 2. \
XXX We could test here whether the use of this character \
set was announced. */ \
inptr += 2; \
ch = cns11643l2_to_ucs4 (&inptr, 2, 0); \
if (ch == __UNKNOWN_10646_CHAR) \
{ \
inptr -= 2; \
result = __GCONV_ILLEGAL_INPUT; \
break; \
} \
} \
else if (set == ASCII_set) \
{ \
/* Almost done, just advance the input pointer. */ \
++inptr; \
} \
else \
{ \
/* That's pretty easy, we have a dedicated functions for this. */ \
if (set == GB2312_set) \
ch = gb2312_to_ucs4 (&inptr, \
NEED_LENGTH_TEST ? inend - inptr : 2, 0); \
else \
{ \
assert (set == CNS11643_1_set); \
ch = cns11643l1_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 , int *setp
#define INIT_PARAMS int set = *setp & CURRENT_MASK; \
int ann = *setp & ~CURRENT_MASK
#define UPDATE_PARAMS *setp = set | ann
#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
#define LOOPFCT TO_LOOP
#define BODY \
{ \
uint32_t ch; \
size_t written = 0; \
\
ch = *((uint32_t *) inptr); \
\
/* First see whether we can write the character using the currently \
selected character set. */ \
if (ch < 0x80) \
{ \
if (set != ASCII_set) \
{ \
*outptr++ = SI; \
set = ASCII_set; \
if (NEED_LENGTH_TEST && outptr == outend) \
{ \
result = __GCONV_FULL_OUTPUT; \
break; \
} \
} \
\
*outptr++ = ch; \
written = 1; \
\
/* At the end of the line we have to clear the `ann' flags since \
every line must contain this information again. */ \
if (ch == L'\n') \
ann = 0; \
} \
else \
{ \
char buf[2]; \
int used; \
\
if (set == GB2312_set || (ann & CNS11643_1_ann) == 0) \
{ \
written = ucs4_to_gb2312 (ch, buf, 2); \
used = GB2312_set; \
} \
else \
{ \
written = ucs4_to_cns11643l1 (ch, buf, 2); \
used = CNS11643_1_set; \
} \
\
if (written == __UNKNOWN_10646_CHAR) \
{ \
/* Cannot convert it using the currently selected SO set. \
Next try the SS2 set. */ \
written = ucs4_to_cns11643l2 (ch, buf, 2); \
if (written != __UNKNOWN_10646_CHAR) \
/* Yep, that worked. */ \
used = CNS11643_2_set; \
else \
{ \
/* Well, see whether we have to change the SO set. */ \
if (set == GB2312_set) \
written = ucs4_to_cns11643l1 (ch, buf, 2); \
else \
written = ucs4_to_gb2312 (ch, buf, 2); \
\
if (written != __UNKNOWN_10646_CHAR) \
/* Oh well, then switch SO. */ \
used = GB2312_set + CNS11643_1_set - set; \
else \
{ \
/* Even this does not work. Error. */ \
result = __GCONV_ILLEGAL_INPUT; \
break; \
} \
} \
} \
assert (written == 2); \
\
/* See whether we have to emit an escape sequence. */ \
if (set != used) \
{ \
/* First see whether we announced that we use this \
character set. */ \
if ((ann & (2 << used)) == 0) \
{ \
const char *escseq; \
\
if (NEED_LENGTH_TEST && outptr + 4 > outend) \
{ \
result = __GCONV_FULL_OUTPUT; \
break; \
} \
\
assert (used >= 1 && used <= 3); \
escseq = "\e$)A\e$)G\e$*H" + (used - 1) * 4; \
*outptr++ = *escseq++; \
*outptr++ = *escseq++; \
*outptr++ = *escseq++; \
*outptr++ = *escseq++; \
\
if (used == GB2312_set) \
ann = (ann & CNS11643_2_ann) | GB2312_ann; \
else if (used == CNS11643_1_set) \
ann = (ann & CNS11643_2_ann) | CNS11643_1_ann; \
else \
ann |= CNS11643_2_ann; \
} \
\
if (used == CNS11643_2_set) \
{ \
if (outptr + 2 > outend) \
{ \
result = __GCONV_FULL_OUTPUT; \
break; \
} \
*outptr++ = SS2_0; \
*outptr++ = SS2_1; \
} \
else \
{ \
/* We only have to emit something is currently ASCII is \
selected. Otherwise we are switching within the \
SO charset. */ \
if (set == ASCII_set) \
{ \
if (outptr + 1 > outend) \
{ \
result = __GCONV_FULL_OUTPUT; \
break; \
} \
*outptr++ = SO; \
} \
} \
\
/* Always test the length here since we have used up all the \
guaranteed output buffer slots. */ \
if (outptr + 2 > outend) \
{ \
result = __GCONV_FULL_OUTPUT; \
break; \
} \
} \
else if (NEED_LENGTH_TEST && outptr + 2 > outend) \
{ \
result = __GCONV_FULL_OUTPUT; \
break; \
} \
\
*outptr++ = buf[0]; \
*outptr++ = buf[1]; \
} \
\
/* Now that we wrote the output increment the input pointer. */ \
inptr += 4; \
}
#define EXTRA_LOOP_DECLS , int *setp
#define INIT_PARAMS int set = *setp & CURRENT_MASK; \
int ann = *setp & ~CURRENT_MASK
#define UPDATE_PARAMS *setp = set | ann
#include <iconv/loop.c>
/* Now define the toplevel functions. */
#include <iconv/skeleton.c>