MSymbol mconv_define_coding |
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const char * |
name, |
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MPlist * |
plist, |
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int(*)(MConverter *) |
resetter, |
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int(*)(const unsigned char *, int, MText *, MConverter *) |
decoder, |
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int(*)(MText *, int, int, unsigned char *, int, MConverter *) |
encoder, |
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void * |
extra_info | |
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) |
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The mconv_define_coding() function defines a new coding system and makes it accessible via a symbol whose name is name. plist specifies parameters of the coding system as below:
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Key is
Mtype , value is a symbol
The value specifies the type of the coding system. It must be Mcharset, Mutf, Miso_2022, or Mnil.
If the type is Mcharset, extra_info is ignored.
If the type is Mutf, extra_info must be a pointer to MCodingInfoUTF.
If the type is Miso_2022, extra_info must be a pointer to MCodingInfoISO2022.
If the type is Mnil, the argument resetter, decoder, and encoder must be supplied. extra_info is ignored. Otherwise, they can be NULL and the m17n library provides proper defaults.
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Key is Mcharsets, value is a plist
The value specifies a list charsets supported by the coding system. The keys of the plist must be Msymbol, and the values must be symbols representing charsets.
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Key is Mflags, value is a plist
If the type is Miso_2022, the values specifies flags to control the ISO 2022 interpreter. The keys of the plist must e Msymbol, and values must be one of the following.
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Mreset_at_eol
If this flag exists, designation and invocation status is reset to the initial state at the end of line.
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Mreset_at_cntl
If this flag exists, designation and invocation status is reset to the initial state at a control character.
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Meight_bit
If this flag exists, the graphic plane right is used.
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Mlong_form
If this flag exists, the over-long escape sequences (ESC '$' '(' <final_byte>) are used for designating the CCS JISX0208.1978, GB2312, and JISX0208.
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Mdesignation_g0
If this flag and Mfull_support exists, designates charsets not listed in the charset list to the graphic register G0.
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Mdesignation_g1
If this flag and Mfull_support exists, designates charsets not listed in the charset list to the graphic register G1.
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Mdesignation_ctext
If this flag and Mfull_support exists, designates charsets not listed in the charset list to a graphic register G0 or G1 based on the criteria of the Compound Text.
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Mdesignation_ctext_ext
If this flag and Mfull_support exists, designates charsets not listed in the charset list to a graphic register G0 or G1, or use extended segment for such charsets based on the criteria of the Compound Text.
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Mlocking_shift
If this flag exists, use locking shift.
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Msingle_shift
If this flag exists, use single shift.
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Msingle_shift_7
If this flag exists, use 7-bit single shift code (0x19).
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Meuc_tw_shift
If this flag exists, use a special shifting according to EUC-TW.
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Miso_6429
This flag is currently ignored.
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Mrevision_number
If this flag exists, use a revision number escape sequence to designate a charset that has a revision number.
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Mfull_support
If this flag exists, support all charsets registered in the International Registry.
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Key is Mdesignation, value is a plist
If the type is Miso_2022, the value specifies how to designate each supported characters. The keys of the plist must be Minteger, and the values must be numbers indicating a graphic registers. The Nth element value is for the Nth charset of the charset list. The value 0..3 means that it is assumed that a charset is already designated to the graphic register 0..3. The negative value G (-4..-1) means that a charset is not designated to any register at first, and if necessary, is designated to the (G+4) graphic register.
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Key is Minvocation, value is a plist
If the type is Miso_2022, the value specifies how to invocate each graphic registers. The plist length must be one or two. The keys of the plist must be Minteger, and the values must be numbers indicating a graphic register. The value of the first element specifies which graphic register is invocated to the graphic plane left. If the length is one, no graphic register is invocated to the graphic plane right. Otherwise, the value of the second element specifies which graphic register is invocated to the graphic plane right.
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Key is Mcode_unit, value is an integer
If the type is Mutf, the value specifies the bit length of a code-unit. It must be 8, 16, or 32.
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Key is Mbom, value is a symbol
If the type is Mutf and the code-unit bit length is 16 or 32, it specifies whether or not to use BOM (Byte Order Mark). If the value is Mnil (default), BOM is not used, else if the value is Mmaybe, the existence of BOM is detected at decoding time, else BOM is used.
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Key is Mlittle_endian, value is a symbol
If the type is Mutf and the code-unit bit length is 16 or 32, it specifies whether or not the encoding is little endian. If the value is Mnil (default), it is big endian, else it is little endian.
resetter is a pointer to a function that resets a converter for the coding system to the initial status. The pointed function is called with one argument, a pointer to a converter object.
decoder is a pointer to a function that decodes a byte sequence according to the coding system. The pointed function is called with four arguments:
- A pointer to the byte sequence to decode.
- The number of bytes to decode.
- A pointer to an M-text to which the decoded characters are appended.
- A pointer to a converter object.
decoder must return 0 if it succeeds. Otherwise it must return -1.
encoder is a pointer to a function that encodes an M-text according to the coding system. The pointed function is called with six arguments:
- A pointer to the M-text to encode.
- The starting position of the encoding.
- The ending position of the encoding.
- A pointer to a memory area where the produced bytes are stored.
- The size of the memory area.
- A pointer to a converter object.
encoder must return 0 if it succeeds. Otherwise it must return -1.
extra_info is a pointer to a data structure that contains extra information about the coding system. The type of the data structure depends on type.
- Return value:
If the operation was successful, mconv_define_coding() returns a symbol whose name is name. If an error is detected, it returns Mnil and assigns an error code to the external variable merror_code.
- Errors:
MERROR_CODING
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The mconv_resolve_coding() function returns symbol if it represents a coding system. Otherwise, canonicalize symbol as to a coding system name, and if the canonicalized name represents a coding system, return it. Otherwise, return Mnil. |
int mconv_list_codings |
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MSymbol ** |
symbols |
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The mconv_list_codings() function makes an array of symbols representing a coding system, stores the pointer to the array in a place pointed to by symbols, and returns the length of the array. |
MConverter* mconv_buffer_converter |
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MSymbol |
name, |
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const unsigned char * |
buf, |
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int |
n | |
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The mconv_buffer_converter() function creates a pointer to a code converter for coding system name. The code converter is bound to buffer area of n bytes pointed to by buf. Subsequent decodings and encodings are done to/from this buffer area.
name can be Mnil. In this case, a coding system associated with the current locale (LC_CTYPE) is used.
- Return value:
- If the operation was successful, mconv_buffer_converter() returns the created code converter. Otherwise it returns
NULL and assigns an error code to the external variable merror_code.
- Errors:
MERROR_SYMBOL , MERROR_CODING
- See Also:
- mconv_stream_converter()
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The mconv_stream_converter() function creates a pointer to a code converter for coding system name. The code converter is bound to stream fp. Subsequent decodings and encodings are done to/from this stream.
name can be Mnil. In this case, a coding system associated with the current locale (LC_CTYPE) is used.
- Return value: If the operation was successful, mconv_stream_converter()
- returns the created code converter. Otherwise it returns
NULL and assigns an error code to the external variable merror_code.
- Errors:
MERROR_SYMBOL , MERROR_CODING
- See Also:
- mconv_buffer_converter()
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int mconv_reset_converter |
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MConverter * |
converter |
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The mconv_reset_converter() function resets code converter converter to the initial state.
- Return value:
- If converter->coding has its own reseter function, mconv_reset_converter() returns the result of that function applied to converter. Otherwise it returns 0.
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The mconv_rebind_buffer() function binds buffer area of n bytes pointed to by buf to code converter converter. Subsequent decodings and encodings are done to/from this newly bound buffer area.
- Return value:
- This function always returns converter.
- See Also:
- mconv_rebind_stream()
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The mconv_rebind_stream() function binds stream fp to code converter converter. Following decodings and encodings are done to/from this newly bound stream.
- Return value:
- This function always returns converter.
- See Also:
- mconv_rebind_buffer()
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MText* mconv_decode_buffer |
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MSymbol |
name, |
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const unsigned char * |
buf, |
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int |
n | |
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The mconv_decode_buffer() function decodes n bytes of the buffer area pointed to by buf based on the coding system name. A temporary code converter for decoding is automatically created and freed.
- Return value:
- If the operation was successful, mconv_decode_buffer() returns the resulting M-text. Otherwise it returns
NULL and assigns an error code to the external variable merror_code.
- Errors:
MERROR_IO , MERROR_CODING
- See Also:
- mconv_decode(), mconv_decode_stream()
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The mconv_decode_stream() function decodes the entire byte sequence read in from stream fp based on the coding system name. A code converter for decoding is automatically created and freed.
- Return value:
- If the operation was successful, mconv_decode_stream() returns the resulting M-text. Otherwise it returns
NULL and assigns an error code to the external variable merror_code.
- Errors:
MERROR_IO , MERROR_CODING
- See Also:
- mconv_decode(), mconv_decode_buffer()
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int mconv_encode_buffer |
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MSymbol |
name, |
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MText * |
mt, |
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unsigned char * |
buf, |
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int |
n | |
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The mconv_encode_buffer() function encodes M-text mt based on coding system name and writes the resulting byte sequence into the buffer area pointed to by buf. At most n bytes are written. A temporary code converter for encoding is automatically created and freed.
- Return value:
- If the operation was successful, mconv_encode_buffer() returns the number of written bytes. Otherwise it returns -1 and assigns an error code to the external variable merror_code.
- Errors:
MERROR_IO , MERROR_CODING
- See Also:
- mconv_encode(), mconv_encode_stream()
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int mconv_encode_stream |
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MSymbol |
name, |
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MText * |
mt, |
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FILE * |
fp | |
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The mconv_encode_stream() function encodes M-text mt based on coding system name and writes the resulting byte sequence to stream fp. A temporary code converter for encoding is automatically created and freed.
- Return value:
- If the operation was successful, mconv_encode_stream() returns the number of written bytes. Otherwise it returns -1 and assigns an error code to the external variable merror_code.
- Errors:
MERROR_IO , MERROR_CODING
- See Also:
- mconv_encode(), mconv_encode_buffer(), mconv_encode_file()
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The mconv_getc() function reads one character from the buffer area or the stream that is currently bound to code converter converter. The decoder of converter is used to decode the byte sequence. The internal status of converter is updated appropriately.
- Return value:
- If the operation was successful, mconv_getc() returns the character read in. If the input source reaches EOF, it returns
EOF without changing the external variable merror_code. If an error is detected, it returns EOF and assigns an error code to merror_code.
- Errors:
MERROR_CODING
- See Also:
- mconv_ungetc(), mconv_putc(), mconv_gets()
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int mconv_ungetc |
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MConverter * |
converter, |
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int |
c | |
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The mconv_ungetc() function pushes character c back to code converter converter. Any number of characters can be pushed back. The lastly pushed back character is firstly read by the subsequent mconv_getc() call. The characters pushed back are registered only in converter; they are not written to the input source. The internal status of converter is updated appropriately.
- Return value:
- If the operation was successful, mconv_ungetc() returns c. Otherwise it returns
EOF and assigns an error code to the external variable merror_code.
- Errors:
MERROR_CODING , MERROR_CHAR
- See Also:
- mconv_getc(), mconv_putc(), mconv_gets()
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The mconv_putc() function writes character c to the buffer area or the stream that is currently bound to code converter converter. The encoder of converter is used to encode the character. The number of bytes actually written is set to the nbytes member of converter. The internal status of converter is updated appropriately.
- Return value:
- If the operation was successful, mconv_putc() returns c. If an error is detected, it returns
EOF and assigns an error code to the external variable merror_code.
- Errors:
MERROR_CODING , MERROR_IO , MERROR_CHAR
- See Also:
- mconv_getc(), mconv_ungetc(), mconv_gets()
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The mconv_gets() function reads one line from the buffer area or the stream that is currently bound to code converter converter. The decoder of converter is used for decoding. The decoded character sequence is appended at the end of M-text mt. The final newline character in the original byte sequence is not appended. The internal status of converter is updated appropriately.
- Return value:
- If the operation was successful, mconv_gets() returns the modified mt. If it encounters EOF without reading a single character, it returns mt without changing it. If an error is detected, it returns
NULL and assigns an error code to merror_code.
- Errors:
MERROR_CODING
- See Also:
- mconv_getc(), mconv_ungetc(), mconv_putc()
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