2 * charset.h - header file for general character set conversion
6 #ifndef charset_charset_h
7 #define charset_charset_h
12 * Enumeration that lists all the multibyte or single-byte
13 * character sets known to this library.
16 CS_NONE
, /* used for reporting errors, etc */
17 CS_ASCII
, /* ordinary US-ASCII is worth having! */
19 CS_ISO8859_1_X11
, /* X font encoding with VT100 glyphs */
101 * This macro is used to initialise a charset_state structure:
103 * charset_state mystate = CHARSET_INIT_STATE;
105 #define CHARSET_INIT_STATE { 0L, 0L } /* a suitable initialiser */
108 * This external variable contains the same data, but is provided
109 * for easy structure-copy assignment:
111 * mystate = charset_init_state;
113 extern const charset_state charset_init_state
;
116 * Routine to convert a MB/SB character set to Unicode.
118 * This routine accepts some number of bytes, updates a state
119 * variable, and outputs some number of Unicode characters. There
120 * are no guarantees. You can't even guarantee that at most one
121 * Unicode character will be output per byte you feed in; for
122 * example, suppose you're reading UTF-8, you've seen E1 80, and
123 * then you suddenly see FE. Now you need to output _two_ error
124 * characters - one for the incomplete sequence E1 80, and one for
125 * the completely invalid UTF-8 byte FE.
127 * Returns the number of wide characters output; will never output
128 * more than the size of the buffer (as specified on input).
129 * Advances the `input' pointer and decrements `inlen', to indicate
130 * how far along the input string it got.
132 * The sequence of `errlen' wide characters pointed to by `errstr'
133 * will be used to indicate a conversion error. If `errstr' is
134 * NULL, `errlen' will be ignored, and the library will choose
135 * something sensible to do on its own. For Unicode, this will be
136 * U+FFFD (REPLACEMENT CHARACTER).
139 int charset_to_unicode(const char **input
, int *inlen
,
140 wchar_t *output
, int outlen
,
141 int charset
, charset_state
*state
,
142 const wchar_t *errstr
, int errlen
);
145 * Routine to convert Unicode to an MB/SB character set.
147 * This routine accepts some number of Unicode characters, updates
148 * a state variable, and outputs some number of bytes.
150 * Returns the number of bytes output; will never output more than
151 * the size of the buffer (as specified on input), and will never
152 * output a partial MB character. Advances the `input' pointer and
153 * decrements `inlen', to indicate how far along the input string
156 * If `error' is non-NULL and a character is found which cannot be
157 * expressed in the output charset, conversion will terminate at
158 * that character (so `input' points to the offending character)
159 * and `*error' will be set to TRUE; if `error' is non-NULL and no
160 * difficult characters are encountered, `*error' will be set to
161 * FALSE. If `error' is NULL, difficult characters will simply be
164 * If `input' is NULL, this routine will output the necessary bytes
165 * to reset the encoding state in any way which might be required
166 * at the end of an output piece of text.
169 int charset_from_unicode(const wchar_t **input
, int *inlen
,
170 char *output
, int outlen
,
171 int charset
, charset_state
*state
, int *error
);
174 * Convert X11 encoding names to and from our charset identifiers.
176 const char *charset_to_xenc(int charset
);
177 int charset_from_xenc(const char *name
);
180 * Convert MIME encoding names to and from our charset identifiers.
182 const char *charset_to_mimeenc(int charset
);
183 int charset_from_mimeenc(const char *name
);
186 * Convert our own encoding names to and from our charset
189 const char *charset_to_localenc(int charset
);
190 int charset_from_localenc(const char *name
);
191 int charset_localenc_nth(int n
);
194 * Convert Mac OS script/region/font to our charset identifiers.
196 int charset_from_macenc(int script
, int region
, int sysvers
,
197 const char *fontname
);
200 * Upgrade a charset identifier to a superset charset which is
201 * often confused with it. For example, people whose MUAs report
202 * their mail as ASCII or ISO8859-1 often in practice turn out to
203 * be using CP1252 quote characters, so when parsing incoming mail
204 * it is prudent to treat ASCII and ISO8859-1 as aliases for CP1252
205 * - and since it's a superset of both, this will cause no
206 * genuinely correct mail to be parsed wrongly.
208 int charset_upgrade(int charset
);
211 * This function returns TRUE if the input charset is a vaguely
212 * sensible superset of ASCII. That is, it returns FALSE for 7-bit
213 * encoding formats such as HZ and UTF-7.
215 int charset_contains_ascii(int charset
);
218 * This function tries to deduce the CS_* identifier of the charset
219 * used in the current C locale. It falls back to CS_ASCII if it
220 * can't figure it out at all, so it will always return a valid
223 * (Note that you should have already called setlocale(LC_CTYPE,
224 * "") to guarantee that this function will do the right thing.)
226 int charset_from_locale(void);
228 #endif /* charset_charset_h */