nls_euc-jp.c

This is a ReiserFs file system driver for Windows NT/2000/XP/Vista.

	}
}

/* EUC to SJIS IBM extended characters (G3 JIS X 0212 block) */
static inline int euc2sjisibm_jisx0212(unsigned char *sjis, const unsigned char euc_hi,
				       const unsigned char euc_lo)
{
	int index, min_index, max_index;
	unsigned short euc;

	min_index = 0;
	max_index = MAP_ELEMENT_OF(euc2sjisibm_jisx0212_map) - 1;
	euc = (euc_hi << 8) | euc_lo;

	while (min_index <= max_index) {
		index = (min_index + max_index) / 2;
		if (euc < euc2sjisibm_jisx0212_map[index].euc)
			max_index = index - 1;
		else
			min_index = index + 1;
		if (euc == euc2sjisibm_jisx0212_map[index].euc) {
			sjis[0] = euc2sjisibm_jisx0212_map[index].sjis[0];
			sjis[1] = euc2sjisibm_jisx0212_map[index].sjis[1];
			return 3;
		}
	}
	return 0;
}

/* EUC to SJIS IBM extended characters (G3 Upper block) */
static inline int euc2sjisibm_g3upper(unsigned char *sjis, const unsigned char euc_hi,
				      const unsigned char euc_lo)
{
	int index;

	if (euc_hi == 0xF3)
		index = ((euc_hi << 8) | euc_lo) - 0xF3F3;
	else
		index = ((euc_hi << 8) | euc_lo) - 0xF4A1 + 12;

	if ((index < 0) || (index >= MAP_ELEMENT_OF(euc2sjisibm_g3upper_map)))
		return 0;

	sjis[0] = euc2sjisibm_g3upper_map[index][0];
	sjis[1] = euc2sjisibm_g3upper_map[index][1];

	return 3;
}

/* EUC to SJIS IBM extended characters (G3 block) */
static inline int euc2sjisibm(unsigned char *sjis, const unsigned char euc_hi,
			      const unsigned char euc_lo)
{
	int n;

#if 0
	if ((euc_hi == 0xA2) && (euc_lo == 0xCC)) {
		sjis[0] = 0xFA;
		sjis[1] = 0x54;
		return 2;
	} else if ((euc_hi == 0xA2) && (euc_lo == 0xE8)) {
		sjis[0] = 0xFA;
		sjis[1] = 0x5B;
		return 2;
	}
#endif
	if ((n = euc2sjisibm_g3upper(sjis, euc_hi, euc_lo))) {
		return n;
	} else if ((n = euc2sjisibm_jisx0212(sjis, euc_hi, euc_lo))) {
		return n;
	}

	return 0;
}

/* NEC/IBM extended characters to IBM extended characters */
static inline int sjisnec2sjisibm(unsigned char *sjisibm,
				  const unsigned char sjisnec_hi,
				  const unsigned char sjisnec_lo)
{
	int count;

	if (! IS_SJIS_NECIBM(sjisnec_hi, sjisnec_lo))
		return 0;

	if ((sjisnec_hi == 0xEE) && (sjisnec_lo == 0xF9)) {
		sjisibm[0] = 0x81;
		sjisibm[1] = 0xCA;
		return 2;
	}

	if ((sjisnec_hi == 0xEE) && (sjisnec_lo >= 0xEF)) {
		count = (sjisnec_hi << 8 | sjisnec_lo)
			- (sjisnec_lo <= 0xF9 ? 0xEEEF : (0xEEEF - 10));
	} else {
		count = (sjisnec_hi - 0xED) * (0xFC - 0x40)
			+ (sjisnec_lo - 0x40) + (0x5C - 0x40);
		if (sjisnec_lo >= 0x7F)
			count--;
	}

	sjisibm[0] = 0xFA + (count / (0xFC - 0x40));
	sjisibm[1] = 0x40 + (count % (0xFC - 0x40));
	if (sjisibm[1] >= 0x7F)
		sjisibm[1]++;

	return 2;
}

static int uni2char(const wchar_t uni,
		    unsigned char *out, int boundlen)
{
	int n;

	if (!p_nls)
		return -EINVAL;
	if ((n = p_nls->uni2char(uni, out, boundlen)) < 0)
		return n;

	/* translate SJIS into EUC-JP */
	if (n == 1) {
		if (IS_SJIS_JISX0201KANA(out[0])) {
			/* JIS X 0201 KANA */
			if (boundlen < 2)
				return -ENAMETOOLONG;

			out[1] = out[0];
			out[0] = SS2;
			return 2;
		}
	} else if (n == 2) {
		/* NEC/IBM extended characters to IBM extended characters */
		sjisnec2sjisibm(out, out[0], out[1]);

		if (IS_SJIS_UDC_LOW(out[0], out[1])) {
			/* User defined characters half low */
			MAP_SJIS2EUC(out[0], out[1], 0xF0, out[0], out[1], 0xF5);
		} else if (IS_SJIS_UDC_HI(out[0], out[1])) {
			/* User defined characters half high */
			unsigned char ch, cl;

			if (boundlen < 3)
				return -ENAMETOOLONG;

			n = 3; ch = out[0]; cl = out[1];
			out[0] = SS3;
			MAP_SJIS2EUC(ch, cl, 0xF5, out[1], out[2], 0xF5);
		} else if (IS_SJIS_IBM(out[0], out[1])) {
			/* IBM extended characters */
			unsigned char euc[3], i;

			n = sjisibm2euc(euc, out[0], out[1]);
			if (boundlen < n)
				return -ENAMETOOLONG;
			for (i = 0; i < n; i++)
				out[i] = euc[i];
		} else if (IS_SJIS_JISX0208(out[0], out[1])) {
			/* JIS X 0208 (include NEC special characters) */
			out[0] = (out[0]^0xA0)*2 + 0x5F;
			if (out[1] > 0x9E)
				out[0]++;

			if (out[1] < 0x7F)
				out[1] = out[1] + 0x61;
			else if (out[1] < 0x9F)
				out[1] = out[1] + 0x60;
			else
				out[1] = out[1] + 0x02;
		} else {
			/* Invalid characters */
			return -EINVAL;
		}
	}
	else
		return -EINVAL;

	return n;
}

static int char2uni(const unsigned char *rawstring, int boundlen,
		    wchar_t *uni)
{
	unsigned char sjis_temp[2];
	int euc_offset, n;

	if ( !p_nls )
		return -EINVAL;
	if (boundlen <= 0)
		return -ENAMETOOLONG;

	/* translate EUC-JP into SJIS */
	if (rawstring[0] > 0x7F) {
		if (rawstring[0] == SS3) {
			if (boundlen < 3)
				return -EINVAL;
			euc_offset = 3;

			if (IS_EUC_UDC_HI(rawstring[1], rawstring[2])) {
				/* User defined characters half high */
				MAP_EUC2SJIS(rawstring[1], rawstring[2], 0xF5,
					     sjis_temp[0], sjis_temp[1], 0xF5);
			} else if (euc2sjisibm(sjis_temp,rawstring[1],rawstring[2])) {
				/* IBM extended characters */
			} else {
				/* JIS X 0212 and Invalid characters*/
				return -EINVAL;

				/* 'GETA' with SJIS coding */
				/* sjis_temp[0] = 0x81; */
				/* sjis_temp[1] = 0xAC; */
			}
		} else {
			if (boundlen < 2)
				return -EINVAL;
			euc_offset = 2;

			if (IS_EUC_JISX0201KANA(rawstring[0], rawstring[1])) {
				/* JIS X 0201 KANA */
				sjis_temp[0] = rawstring[1];
				sjis_temp[1] = 0x00;
			} else if (IS_EUC_UDC_LOW(rawstring[0], rawstring[1])) {
				/* User defined characters half low */
				MAP_EUC2SJIS(rawstring[0], rawstring[1], 0xF5,
					     sjis_temp[0], sjis_temp[1], 0xF0);
			} else if (IS_EUC_JISX0208(rawstring[0], rawstring[1])) {
				/* JIS X 0208 (include NEC spesial characters) */
				sjis_temp[0] = ((rawstring[0]-0x5f)/2) ^ 0xA0;
				if (!(rawstring[0] & 1))
					sjis_temp[1] = rawstring[1] - 0x02;
				else if (rawstring[1] < 0xE0)
					sjis_temp[1] = rawstring[1] - 0x61;
				else
					sjis_temp[1] = rawstring[1] - 0x60;
			} else {
				/* Invalid characters */
				return -EINVAL;
			}
		}
	} else {
		euc_offset = 1;

		/* JIS X 0201 ROMAJI */
		sjis_temp[0] = rawstring[0];
		sjis_temp[1] = 0x00;
	}

	if ( (n = p_nls->char2uni(sjis_temp, sizeof(sjis_temp), uni)) < 0)
		return n;

	return euc_offset;
}

static struct nls_table table = {
	"euc-jp",
	uni2char,
	char2uni,
	NULL,
	NULL,
	THIS_MODULE,
};

static int __init init_nls_euc_jp(void)
{
	p_nls = load_nls("cp932");

	if (p_nls) {
		table.charset2upper = p_nls->charset2upper;
		table.charset2lower = p_nls->charset2lower;
		return register_nls(&table);
	}

	return -EINVAL;
}

static void __exit exit_nls_euc_jp(void)
{
	unregister_nls(&table);
	unload_nls(p_nls);
}

module_init(init_nls_euc_jp)
module_exit(exit_nls_euc_jp)

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 *
---------------------------------------------------------------------------
 * Local variables:
 * c-indent-level: 8
 * c-brace-imaginary-offset: 0
 * c-brace-offset: -8
 * c-argdecl-indent: 8
 * c-label-offset: -8
 * c-continued-statement-offset: 8
 * c-continued-brace-offset: 0
 * End:
 */