src/include/mb/pg_wchar.h

/*-------------------------------------------------------------------------
 *
 * pg_wchar.h
 *	  multibyte-character support
 *
 * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * $PostgreSQL: pgsql/src/include/mb/pg_wchar.h,v 1.91 2009/06/11 14:49:11 momjian Exp $
 *
 *	NOTES
 *		This is used both by the backend and by libpq, but should not be
 *		included by libpq client programs.	In particular, a libpq client
 *		should not assume that the encoding IDs used by the version of libpq
 *		it's linked to match up with the IDs declared here.
 *
 *-------------------------------------------------------------------------
 */
#ifndef PG_WCHAR_H
#define PG_WCHAR_H

#include <sys/types.h>

/*
 * The pg_wchar type
 */
typedef unsigned int pg_wchar;

/*
 * various definitions for EUC
 */
#define SS2 0x8e				/* single shift 2 (JIS0201) */
#define SS3 0x8f				/* single shift 3 (JIS0212) */

/*
 * SJIS validation macros
 */
#define ISSJISHEAD(c) (((c) >= 0x81 && (c) <= 0x9f) || ((c) >= 0xe0 && (c) <= 0xfc))
#define ISSJISTAIL(c) (((c) >= 0x40 && (c) <= 0x7e) || ((c) >= 0x80 && (c) <= 0xfc))

/*
 * Leading byte types or leading prefix byte for MULE internal code.
 * See http://www.xemacs.org for more details.	(there is a doc titled
 * "XEmacs Internals Manual", "MULE Character Sets and Encodings"
 * section.)
 */
/*
 * Is a leading byte for "official" single byte encodings?
 */
#define IS_LC1(c)	((unsigned char)(c) >= 0x81 && (unsigned char)(c) <= 0x8d)
/*
 * Is a prefix byte for "private" single byte encodings?
 */
#define IS_LCPRV1(c)	((unsigned char)(c) == 0x9a || (unsigned char)(c) == 0x9b)
/*
 * Is a leading byte for "official" multibyte encodings?
 */
#define IS_LC2(c)	((unsigned char)(c) >= 0x90 && (unsigned char)(c) <= 0x99)
/*
 * Is a prefix byte for "private" multibyte encodings?
 */
#define IS_LCPRV2(c)	((unsigned char)(c) == 0x9c || (unsigned char)(c) == 0x9d)

/*----------------------------------------------------
 * leading characters
 *----------------------------------------------------
 */

/*
 * Official single byte encodings (0x81-0x8e)
 */
#define LC_ISO8859_1		0x81	/* ISO8859 Latin 1 */
#define LC_ISO8859_2		0x82	/* ISO8859 Latin 2 */
#define LC_ISO8859_3		0x83	/* ISO8859 Latin 3 */
#define LC_ISO8859_4		0x84	/* ISO8859 Latin 4 */
#define LC_TIS620			0x85	/* Thai (not supported yet) */
#define LC_ISO8859_7		0x86	/* Greek (not supported yet) */
#define LC_ISO8859_6		0x87	/* Arabic (not supported yet) */
#define LC_ISO8859_8		0x88	/* Hebrew (not supported yet) */
#define LC_JISX0201K		0x89	/* Japanese 1 byte kana */
#define LC_JISX0201R		0x8a	/* Japanese 1 byte Roman */
/* Note that 0x8b seems to be unused as of Emacs 20.7.
 * However, there might be a chance that 0x8b could be used
 * in later version of Emacs.
 */
#define LC_KOI8_R			0x8b	/* Cyrillic KOI8-R */
#define LC_KOI8_U			0x8b	/* Cyrillic KOI8-U */
#define LC_ISO8859_5		0x8c	/* ISO8859 Cyrillic */
#define LC_ISO8859_9		0x8d	/* ISO8859 Latin 5 (not supported yet) */
/* #define FREE				0x8e	free (unused) */

/*
 * Unused
 */
#define CONTROL_1			0x8f	/* control characters (unused) */

/*
 * Official multibyte byte encodings (0x90-0x99)
 * 0x9a-0x9d are free. 0x9e and 0x9f are reserved.
 */
#define LC_JISX0208_1978	0x90	/* Japanese Kanji, old JIS (not supported) */
/* #define FREE				0x90	free (unused) */
#define LC_GB2312_80		0x91	/* Chinese */
#define LC_JISX0208			0x92	/* Japanese Kanji (JIS X 0208) */
#define LC_KS5601			0x93	/* Korean */
#define LC_JISX0212			0x94	/* Japanese Kanji (JIS X 0212) */
#define LC_CNS11643_1		0x95	/* CNS 11643-1992 Plane 1 */
#define LC_CNS11643_2		0x96	/* CNS 11643-1992 Plane 2 */
/* #define FREE				0x97	free (unused) */
#define LC_BIG5_1			0x98	/* Plane 1 Chinese traditional (not supported) */
#define LC_BIG5_2			0x99	/* Plane 1 Chinese traditional (not supported) */

/*
 * Private single byte encodings (0xa0-0xef)
 */
#define LC_SISHENG			0xa0/* Chinese SiSheng characters for
								 * PinYin/ZhuYin (not supported) */
#define LC_IPA				0xa1/* IPA (International Phonetic Association)
								 * (not supported) */
#define LC_VISCII_LOWER		0xa2/* Vietnamese VISCII1.1 lower-case (not
								 * supported) */
#define LC_VISCII_UPPER		0xa3/* Vietnamese VISCII1.1 upper-case (not
								 * supported) */
#define LC_ARABIC_DIGIT		0xa4	/* Arabic digit (not supported) */
#define LC_ARABIC_1_COLUMN	0xa5	/* Arabic 1-column (not supported) */
#define LC_ASCII_RIGHT_TO_LEFT	0xa6	/* ASCII (left half of ISO8859-1) with
										 * right-to-left direction (not
										 * supported) */
#define LC_LAO				0xa7/* Lao characters (ISO10646 0E80..0EDF) (not
								 * supported) */
#define LC_ARABIC_2_COLUMN	0xa8	/* Arabic 1-column (not supported) */

/*
 * Private multibyte encodings (0xf0-0xff)
 */
#define LC_INDIAN_1_COLUMN	0xf0/* Indian charset for 1-column width glypps
								 * (not supported) */
#define LC_TIBETAN_1_COLUMN 0xf1	/* Tibetan 1 column glyph (not supported) */
#define LC_ETHIOPIC			0xf5	/* Ethiopic characters (not supported) */
#define LC_CNS11643_3		0xf6	/* CNS 11643-1992 Plane 3 */
#define LC_CNS11643_4		0xf7	/* CNS 11643-1992 Plane 4 */
#define LC_CNS11643_5		0xf8	/* CNS 11643-1992 Plane 5 */
#define LC_CNS11643_6		0xf9	/* CNS 11643-1992 Plane 6 */
#define LC_CNS11643_7		0xfa	/* CNS 11643-1992 Plane 7 */
#define LC_INDIAN_2_COLUMN	0xfb/* Indian charset for 2-column width glypps
								 * (not supported) */
#define LC_TIBETAN			0xfc	/* Tibetan (not supported) */
/* #define FREE				0xfd	free (unused) */
/* #define FREE				0xfe	free (unused) */
/* #define FREE				0xff	free (unused) */

/*
 * PostgreSQL encoding identifiers
 *
 * WARNING: the order of this enum must be same as order of entries
 *			in the pg_enc2name_tbl[] array (in mb/encnames.c), and
 *			in the pg_wchar_table[] array (in mb/wchar.c)!
 *
 *			If you add some encoding don't forget to check
 *			PG_ENCODING_BE_LAST macro.
 *
 * PG_SQL_ASCII is default encoding and must be = 0.
 *
 * XXX	We must avoid renumbering any backend encoding until libpq's major
 * version number is increased beyond 5; it turns out that the backend
 * encoding IDs are effectively part of libpq's ABI as far as 8.2 initdb and
 * psql are concerned.
 */
typedef enum pg_enc
{
	PG_SQL_ASCII = 0,			/* SQL/ASCII */
	PG_EUC_JP,					/* EUC for Japanese */
	PG_EUC_CN,					/* EUC for Chinese */
	PG_EUC_KR,					/* EUC for Korean */
	PG_EUC_TW,					/* EUC for Taiwan */
	PG_EUC_JIS_2004,			/* EUC-JIS-2004 */
	PG_UTF8,					/* Unicode UTF8 */
	PG_MULE_INTERNAL,			/* Mule internal code */
	PG_LATIN1,					/* ISO-8859-1 Latin 1 */
	PG_LATIN2,					/* ISO-8859-2 Latin 2 */
	PG_LATIN3,					/* ISO-8859-3 Latin 3 */
	PG_LATIN4,					/* ISO-8859-4 Latin 4 */
	PG_LATIN5,					/* ISO-8859-9 Latin 5 */
	PG_LATIN6,					/* ISO-8859-10 Latin6 */
	PG_LATIN7,					/* ISO-8859-13 Latin7 */
	PG_LATIN8,					/* ISO-8859-14 Latin8 */
	PG_LATIN9,					/* ISO-8859-15 Latin9 */
	PG_LATIN10,					/* ISO-8859-16 Latin10 */
	PG_WIN1256,					/* windows-1256 */
	PG_WIN1258,					/* Windows-1258 */
	PG_WIN866,					/* (MS-DOS CP866) */
	PG_WIN874,					/* windows-874 */
	PG_KOI8R,					/* KOI8-R */
	PG_WIN1251,					/* windows-1251 */
	PG_WIN1252,					/* windows-1252 */
	PG_ISO_8859_5,				/* ISO-8859-5 */
	PG_ISO_8859_6,				/* ISO-8859-6 */
	PG_ISO_8859_7,				/* ISO-8859-7 */
	PG_ISO_8859_8,				/* ISO-8859-8 */
	PG_WIN1250,					/* windows-1250 */
	PG_WIN1253,					/* windows-1253 */
	PG_WIN1254,					/* windows-1254 */
	PG_WIN1255,					/* windows-1255 */
	PG_WIN1257,					/* windows-1257 */
	PG_KOI8U,					/* KOI8-U */
	/* PG_ENCODING_BE_LAST points to the above entry */

	/* followings are for client encoding only */
	PG_SJIS,					/* Shift JIS (Winindows-932) */
	PG_BIG5,					/* Big5 (Windows-950) */
	PG_GBK,						/* GBK (Windows-936) */
	PG_UHC,						/* UHC (Windows-949) */
	PG_GB18030,					/* GB18030 */
	PG_JOHAB,					/* EUC for Korean JOHAB */
	PG_SHIFT_JIS_2004,			/* Shift-JIS-2004 */
	_PG_LAST_ENCODING_			/* mark only */

} pg_enc;

#define PG_ENCODING_BE_LAST PG_KOI8U

/*
 * Please use these tests before access to pg_encconv_tbl[]
 * or to other places...
 */
#define PG_VALID_BE_ENCODING(_enc) \
		((_enc) >= 0 && (_enc) <= PG_ENCODING_BE_LAST)

#define PG_ENCODING_IS_CLIENT_ONLY(_enc) \
		((_enc) > PG_ENCODING_BE_LAST && (_enc) < _PG_LAST_ENCODING_)

#define PG_VALID_ENCODING(_enc) \
		((_enc) >= 0 && (_enc) < _PG_LAST_ENCODING_)

/* On FE are possible all encodings */
#define PG_VALID_FE_ENCODING(_enc)	PG_VALID_ENCODING(_enc)

/*
 * Encoding names with all aliases
 */
typedef struct pg_encname
{
	char	   *name;
	pg_enc		encoding;
} pg_encname;

extern pg_encname pg_encname_tbl[];
extern unsigned int pg_encname_tbl_sz;

/*
 * Careful:
 *
 * if (PG_VALID_ENCODING(encoding))
 *		pg_enc2name_tbl[ encoding ];
 */
typedef struct pg_enc2name
{
	char	   *name;
	pg_enc		encoding;
} pg_enc2name;

extern pg_enc2name pg_enc2name_tbl[];

/*
 * Encoding names for gettext
 */
typedef struct pg_enc2gettext
{
	pg_enc		encoding;
	const char *name;
} pg_enc2gettext;

extern pg_enc2gettext pg_enc2gettext_tbl[];

/*
 * pg_wchar stuff
 */
typedef int (*mb2wchar_with_len_converter) (const unsigned char *from,
														pg_wchar *to,
														int len);

typedef int (*mblen_converter) (const unsigned char *mbstr);

typedef int (*mbdisplaylen_converter) (const unsigned char *mbstr);

typedef int (*mbverifier) (const unsigned char *mbstr, int len);

typedef struct
{
	mb2wchar_with_len_converter mb2wchar_with_len;		/* convert a multibyte
														 * string to a wchar */
	mblen_converter mblen;		/* get byte length of a char */
	mbdisplaylen_converter dsplen;		/* get display width of a char */
	mbverifier	mbverify;		/* verify multibyte sequence */
	int			maxmblen;		/* max bytes for a char in this encoding */
} pg_wchar_tbl;

extern pg_wchar_tbl pg_wchar_table[];

/*
 * UTF-8 to local code conversion map
 * Note that we limit the max length of UTF-8 to 4 bytes,
 * which is UCS-4 00010000-001FFFFF range.
 */
typedef struct
{
	uint32		utf;			/* UTF-8 */
	uint32		code;			/* local code */
} pg_utf_to_local;

/*
 * local code to UTF-8 conversion map
 */
typedef struct
{
	uint32		code;			/* local code */
	uint32		utf;			/* UTF-8 */
} pg_local_to_utf;

/*
 * UTF-8 to local code conversion map(combined characters)
 */
typedef struct
{
	uint32		utf1;			/* UTF-8 code 1 */
	uint32		utf2;			/* UTF-8 code 2 */
	uint32		code;			/* local code */
} pg_utf_to_local_combined;

/*
 * local code to UTF-8 conversion map(combined characters)
 */
typedef struct
{
	uint32		code;			/* local code */
	uint32		utf1;			/* UTF-8 code 1 */
	uint32		utf2;			/* UTF-8 code 2 */
} pg_local_to_utf_combined;

/*
 * Support macro for encoding conversion functions to validate their
 * arguments.  (This could be made more compact if we included fmgr.h
 * here, but we don't want to do that because this header file is also
 * used by frontends.)
 */
#define CHECK_ENCODING_CONVERSION_ARGS(srcencoding,destencoding) \
	check_encoding_conversion_args(PG_GETARG_INT32(0), \
								   PG_GETARG_INT32(1), \
								   PG_GETARG_INT32(4), \
								   (srcencoding), \
								   (destencoding))


/*
 * These functions are considered part of libpq's exported API and
 * are also declared in libpq-fe.h.
 */
extern int	pg_char_to_encoding(const char *name);
extern const char *pg_encoding_to_char(int encoding);
extern int	pg_valid_server_encoding_id(int encoding);

/*
 * Remaining functions are not considered part of libpq's API, though many
 * of them do exist inside libpq.
 */
extern pg_encname *pg_char_to_encname_struct(const char *name);

extern int	pg_mb2wchar(const char *from, pg_wchar *to);
extern int	pg_mb2wchar_with_len(const char *from, pg_wchar *to, int len);
extern int pg_encoding_mb2wchar_with_len(int encoding,
							  const char *from, pg_wchar *to, int len);
extern int	pg_char_and_wchar_strcmp(const char *s1, const pg_wchar *s2);
extern int	pg_wchar_strncmp(const pg_wchar *s1, const pg_wchar *s2, size_t n);
extern int	pg_char_and_wchar_strncmp(const char *s1, const pg_wchar *s2, size_t n);
extern size_t pg_wchar_strlen(const pg_wchar *wstr);
extern int	pg_mblen(const char *mbstr);
extern int	pg_dsplen(const char *mbstr);
extern int	pg_encoding_mblen(int encoding, const char *mbstr);
extern int	pg_encoding_dsplen(int encoding, const char *mbstr);
extern int	pg_encoding_verifymb(int encoding, const char *mbstr, int len);
extern int	pg_mule_mblen(const unsigned char *mbstr);
extern int	pg_mic_mblen(const unsigned char *mbstr);
extern int	pg_mbstrlen(const char *mbstr);
extern int	pg_mbstrlen_with_len(const char *mbstr, int len);
extern int	pg_mbcliplen(const char *mbstr, int len, int limit);
extern int pg_encoding_mbcliplen(int encoding, const char *mbstr,
					  int len, int limit);
extern int	pg_mbcharcliplen(const char *mbstr, int len, int imit);
extern int	pg_encoding_max_length(int encoding);
extern int	pg_database_encoding_max_length(void);

#ifdef USE_WIDE_UPPER_LOWER
extern size_t wchar2char(char *to, const wchar_t *from, size_t tolen);
extern size_t char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen);
#endif

extern void SetDefaultClientEncoding(void); /* Obsolete? */
extern int	SetClientEncoding(int encoding, bool doit);
extern void InitializeClientEncoding(void);
extern int	pg_get_client_encoding(void);
extern const char *pg_get_client_encoding_name(void);

extern void SetDatabaseEncoding(int encoding);
extern int	GetDatabaseEncoding(void);
extern const char *GetDatabaseEncodingName(void);
extern void pg_bind_textdomain_codeset(const char *domainname);

extern int	pg_valid_client_encoding(const char *name);
extern int	pg_valid_server_encoding(const char *name);

extern unsigned char *unicode_to_utf8(pg_wchar c, unsigned char *utf8string);
extern int	pg_utf_mblen(const unsigned char *);
extern unsigned char *pg_do_encoding_conversion(unsigned char *src, int len,
						  int src_encoding,
						  int dest_encoding);

extern char *pg_client_to_server(const char *s, int len);
extern char *pg_any_to_server(const char *s, int len, int encoding);
extern char *pg_server_to_client(const char *s, int len);
extern char *pg_custom_to_server(const char *s, int len, int src_encoding, void *cep); /* Obsolete? */
extern char *pg_server_to_custom(const char *s, int len, int dest_encoding, void *cep); /* Obsolete? */

extern unsigned short BIG5toCNS(unsigned short big5, unsigned char *lc);
extern unsigned short CNStoBIG5(unsigned short cns, unsigned char lc);

extern void LocalToUtf(const unsigned char *iso, unsigned char *utf,
		   const pg_local_to_utf *map, const pg_local_to_utf_combined *cmap,
		   int size1, int size2, int encoding, int len);

extern void UtfToLocal(const unsigned char *utf, unsigned char *iso,
		   const pg_utf_to_local *map, const pg_utf_to_local_combined *cmap,
		   int size1, int size2, int encoding, int len);

extern bool pg_verifymbstr(const char *mbstr, int len, bool noError);
extern bool pg_verify_mbstr(int encoding, const char *mbstr, int len,
				bool noError);
extern int pg_verify_mbstr_len(int encoding, const char *mbstr, int len,
					bool noError);

extern void check_encoding_conversion_args(int src_encoding,
							   int dest_encoding,
							   int len,
							   int expected_src_encoding,
							   int expected_dest_encoding);

extern void report_invalid_encoding(int encoding, const char *mbstr, int len);
extern void report_untranslatable_char(int src_encoding, int dest_encoding,
						   const char *mbstr, int len);

extern void pg_ascii2mic(const unsigned char *l, unsigned char *p, int len);
extern void pg_mic2ascii(const unsigned char *mic, unsigned char *p, int len);
extern void latin2mic(const unsigned char *l, unsigned char *p, int len,
		  int lc, int encoding);
extern void mic2latin(const unsigned char *mic, unsigned char *p, int len,
		  int lc, int encoding);
extern void latin2mic_with_table(const unsigned char *l, unsigned char *p,
					 int len, int lc, int encoding,
					 const unsigned char *tab);
extern void mic2latin_with_table(const unsigned char *mic, unsigned char *p,
					 int len, int lc, int encoding,
					 const unsigned char *tab);

extern bool pg_utf8_islegal(const unsigned char *source, int length);

#endif   /* PG_WCHAR_H */