diff options
Diffstat (limited to 'compat/mingw.h')
| -rw-r--r-- | compat/mingw.h | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/compat/mingw.h b/compat/mingw.h index d3cffb7994..921ba08b1d 100644 --- a/compat/mingw.h +++ b/compat/mingw.h @@ -357,6 +357,110 @@ void mingw_open_html(const char *path); char **make_augmented_environ(const char *const *vars); void free_environ(char **env); +/** + * Converts UTF-8 encoded string to UTF-16LE. + * + * To support repositories with legacy-encoded file names, invalid UTF-8 bytes + * 0xa0 - 0xff are converted to corresponding printable Unicode chars \u00a0 - + * \u00ff, and invalid UTF-8 bytes 0x80 - 0x9f (which would make non-printable + * Unicode) are converted to hex-code. + * + * Lead-bytes not followed by an appropriate number of trail-bytes, over-long + * encodings and 4-byte encodings > \u10ffff are detected as invalid UTF-8. + * + * Maximum space requirement for the target buffer is two wide chars per UTF-8 + * char (((strlen(utf) * 2) + 1) [* sizeof(wchar_t)]). + * + * The maximum space is needed only if the entire input string consists of + * invalid UTF-8 bytes in range 0x80-0x9f, as per the following table: + * + * | | UTF-8 | UTF-16 | + * Code point | UTF-8 sequence | bytes | words | ratio + * --------------+-------------------+-------+--------+------- + * 000000-00007f | 0-7f | 1 | 1 | 1 + * 000080-0007ff | c2-df + 80-bf | 2 | 1 | 0.5 + * 000800-00ffff | e0-ef + 2 * 80-bf | 3 | 1 | 0.33 + * 010000-10ffff | f0-f4 + 3 * 80-bf | 4 | 2 (a) | 0.5 + * invalid | 80-9f | 1 | 2 (b) | 2 + * invalid | a0-ff | 1 | 1 | 1 + * + * (a) encoded as UTF-16 surrogate pair + * (b) encoded as two hex digits + * + * Note that, while the UTF-8 encoding scheme can be extended to 5-byte, 6-byte + * or even indefinite-byte sequences, the largest valid code point \u10ffff + * encodes as only 4 UTF-8 bytes. + * + * Parameters: + * wcs: wide char target buffer + * utf: string to convert + * wcslen: size of target buffer (in wchar_t's) + * utflen: size of string to convert, or -1 if 0-terminated + * + * Returns: + * length of converted string (_wcslen(wcs)), or -1 on failure + * + * Errors: + * EINVAL: one of the input parameters is invalid (e.g. NULL) + * ERANGE: the output buffer is too small + */ +int xutftowcsn(wchar_t *wcs, const char *utf, size_t wcslen, int utflen); + +/** + * Simplified variant of xutftowcsn, assumes input string is \0-terminated. + */ +static inline int xutftowcs(wchar_t *wcs, const char *utf, size_t wcslen) +{ + return xutftowcsn(wcs, utf, wcslen, -1); +} + +/** + * Simplified file system specific variant of xutftowcsn, assumes output + * buffer size is MAX_PATH wide chars and input string is \0-terminated, + * fails with ENAMETOOLONG if input string is too long. + */ +static inline int xutftowcs_path(wchar_t *wcs, const char *utf) +{ + int result = xutftowcsn(wcs, utf, MAX_PATH, -1); + if (result < 0 && errno == ERANGE) + errno = ENAMETOOLONG; + return result; +} + +/** + * Converts UTF-16LE encoded string to UTF-8. + * + * Maximum space requirement for the target buffer is three UTF-8 chars per + * wide char ((_wcslen(wcs) * 3) + 1). + * + * The maximum space is needed only if the entire input string consists of + * UTF-16 words in range 0x0800-0xd7ff or 0xe000-0xffff (i.e. \u0800-\uffff + * modulo surrogate pairs), as per the following table: + * + * | | UTF-16 | UTF-8 | + * Code point | UTF-16 sequence | words | bytes | ratio + * --------------+-----------------------+--------+-------+------- + * 000000-00007f | 0000-007f | 1 | 1 | 1 + * 000080-0007ff | 0080-07ff | 1 | 2 | 2 + * 000800-00ffff | 0800-d7ff / e000-ffff | 1 | 3 | 3 + * 010000-10ffff | d800-dbff + dc00-dfff | 2 | 4 | 2 + * + * Note that invalid code points > 10ffff cannot be represented in UTF-16. + * + * Parameters: + * utf: target buffer + * wcs: wide string to convert + * utflen: size of target buffer + * + * Returns: + * length of converted string, or -1 on failure + * + * Errors: + * EINVAL: one of the input parameters is invalid (e.g. NULL) + * ERANGE: the output buffer is too small + */ +int xwcstoutf(char *utf, const wchar_t *wcs, size_t utflen); + /* * A critical section used in the implementation of the spawn * functions (mingw_spawnv[p]e()) and waitpid(). Intialised in |