/*

* utf8_and_sjis_eudc.c: SJIS EUDC <--> UTF8

*

* Copyright (c) 2010, NIPPON TELEGRAPH AND TELEPHONE CORPORATION

*

* SJIS : F040 - F9FF

* UTF8 : E000 - E757

*/

#include "postgres.h"

#include "fmgr.h"

#include "mb/pg_wchar.h"

#include "eudc.h"

#include "pgut/pgut-be.h"

static PGFunction sjis_to_utf8 = NULL;

static PGFunction utf8_to_sjis = NULL;

PG_FUNCTION_INFO_V1(sjis_eudc_to_utf8);

PG_FUNCTION_INFO_V1(utf8_to_sjis_eudc);

extern Datum PGDLLEXPORT sjis_eudc_to_utf8(PG_FUNCTION_ARGS);

extern Datum PGDLLEXPORT utf8_to_sjis_eudc(PG_FUNCTION_ARGS);

/* ----------

* conv_proc(

* INTEGER, -- source encoding id

* INTEGER, -- destination encoding id

* CSTRING, -- source string (null terminated C string)

* CSTRING, -- destination string (null terminated C string)

* INTEGER -- source string length

* ) returns VOID;

* ----------

*/

Datum

sjis_eudc_to_utf8(PG_FUNCTION_ARGS)

{

unsigned char *src = (unsigned char *) PG_GETARG_CSTRING(2);

unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);

unsigned char *p;

unsigned char *fallback_character = NULL;

int len = PG_GETARG_INT32(4);

int sjis_len;

int clen;

CHECK_ENCODING_CONVERSION_ARGS(PG_SJIS, PG_UTF8);

if (sjis_to_utf8 == NULL)

sjis_to_utf8 = load_external_function(

"utf8_and_sjis", "sjis_to_utf8", true, NULL);

*dest = '\0';

p = src;

sjis_len = 0;

for (; len > 0; len -= clen)

{

const unsigned char *c = p + sjis_len;

if (c[0] == '\0')

report_invalid_encoding(PG_SJIS, (const char *) p + sjis_len, len);

if (c[0] >= 0xf0 && c[0] <= 0xf9 && len >= 2 && ISSJISTAIL(c[1]))

{

int ucs;

int m;

int n;

clen = 2;

/* SJIS to UTF8 */

if (sjis_len > 0)

{

DirectFunctionCall5(sjis_to_utf8, PG_SJIS, PG_UTF8,

CStringGetDatum(p), CStringGetDatum(dest),

sjis_len);

dest = dest + strlen((char *) dest);

p += sjis_len;

sjis_len = 0;

}

p += clen;

elog(eudc_log_level,

"eudc character found: %02x%02x in SJIS to UTF8 conversion",

c[0], c[1]);

/* SJIS EUDC to UTF8 */

if (eudc_fallback_character && eudc_fallback_character[0])

{

/* map to fallback character */

int i;

if (fallback_character == NULL)

{

fallback_character = pg_do_encoding_conversion(

(unsigned char *) eudc_fallback_character,

strlen(eudc_fallback_character),

GetDatabaseEncoding(),

PG_UTF8);

}

for (i = 0; fallback_character[i]; i++)

*dest++ = fallback_character[i];

}

else

{

/* linear mapping */

n = c[0] - 0xf0;

m = c[1] - 0x40;

if (m >= 0x40)

m--;

ucs = 0xe000 + n * 188 + m;

*dest++ = (ucs >> 12) | 0xe0;

*dest++ = (ucs & 0x0fc0) >> 6 | 0x80;

*dest++ = (ucs & 0x003f) | 0x80;

}

*dest = '\0';

}

else

{

clen = (ISSJISHEAD(c[0]) ? 2 : 1);

sjis_len += clen;

}

}

/* SJIS to UTF8 */

if (sjis_len > 0)

DirectFunctionCall5(sjis_to_utf8, PG_SJIS, PG_UTF8,

CStringGetDatum(p), CStringGetDatum(dest),

sjis_len);

if (fallback_character != NULL &&

fallback_character != (unsigned char*) eudc_fallback_character)

pfree(fallback_character);

PG_RETURN_VOID();

}

Datum

utf8_to_sjis_eudc(PG_FUNCTION_ARGS)

{

unsigned char *src = (unsigned char *) PG_GETARG_CSTRING(2);

unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);

unsigned char *p;

unsigned char *fallback_character = NULL;

int len = PG_GETARG_INT32(4);

int utf8_len;

int clen;

CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_SJIS);

if (utf8_to_sjis == NULL)

utf8_to_sjis = load_external_function(

"utf8_and_sjis", "utf8_to_sjis", true, NULL);

*dest = '\0';

p = src;

utf8_len = 0;

for (; len > 0; len -= clen)

{

const unsigned char *c = p + utf8_len;

int ucs;

if (c[0] == '\0')

break;

clen = pg_utf_mblen(p + utf8_len);

if (len < clen)

break;

if (clen != 3)

{

utf8_len += clen;

continue;

}

ucs = (((int) c[0] & 0x0f) << 12) |

(((int) c[1] & 0x3f) << 6) |

((int) c[2] & 0x3f);

if (ucs >= 0xe000 && ucs <= 0xe757)

{

int m;

int n;

/* UTF8 to SJIS */

if (utf8_len > 0)

{

DirectFunctionCall5(utf8_to_sjis, PG_UTF8, PG_SJIS,

CStringGetDatum(p), CStringGetDatum(dest),

utf8_len);

dest = dest + strlen((char *) dest);

p += utf8_len;

utf8_len = 0;

}

p += clen;

elog(eudc_log_level,

"eudc character found: %02x%02x%02x in UTF8 to SJIS conversion",

c[0], c[1], c[2]);

/* UTF8 to SJIS EUDC */

if (eudc_fallback_character && eudc_fallback_character[0])

{

/* map to fallback character */

int i;

if (fallback_character == NULL)

{

fallback_character = pg_do_encoding_conversion(

(unsigned char *) eudc_fallback_character,

strlen(eudc_fallback_character),

GetDatabaseEncoding(),

PG_SJIS);

}

for (i = 0; fallback_character[i]; i++)

*dest++ = fallback_character[i];

}

else

{

/* linear mapping */

m = (ucs - 0xE000) % 188;

n = (ucs - 0xE000) / 188;

if (m >= 63)

m++;

/* sjis = 0xF040 + n * 0x100 + m */

*dest++ = 0xf0 + n;

*dest++ = 0x40 + m;

}

*dest = '\0';

}

else

utf8_len += clen;

}

if (len > 0)

report_invalid_encoding(PG_UTF8, (const char *) p + utf8_len, len);

/* UTF8 to SJIS */

if (utf8_len > 0)

DirectFunctionCall5(utf8_to_sjis, PG_UTF8, PG_SJIS,

CStringGetDatum(p), CStringGetDatum(dest),

utf8_len);

if (fallback_character != NULL &&

fallback_character != (unsigned char*) eudc_fallback_character)

pfree(fallback_character);

PG_RETURN_VOID();

}