@subheading stringprep_utf8_to_unichar
@anchor{stringprep_utf8_to_unichar}
@deftypefun {uint32_t} {stringprep_utf8_to_unichar} (const char * @var{p})
@var{p}: a pointer to Unicode character encoded as UTF-8

Converts a sequence of bytes encoded as UTF-8 to a Unicode character.
If @code{p} does not point to a valid UTF-8 encoded character, results are
undefined.

@strong{Return value:} the resulting character.
@end deftypefun

@subheading stringprep_unichar_to_utf8
@anchor{stringprep_unichar_to_utf8}
@deftypefun {int} {stringprep_unichar_to_utf8} (uint32_t @var{c}, char * @var{outbuf})
@var{c}: a ISO10646 character code

@var{outbuf}: output buffer, must have at least 6 bytes of space.
If @code{NULL}, the length will be computed and returned
and nothing will be written to @code{outbuf}.

Converts a single character to UTF-8.

@strong{Return value:} number of bytes written.
@end deftypefun

@subheading stringprep_utf8_to_ucs4
@anchor{stringprep_utf8_to_ucs4}
@deftypefun {uint32_t *} {stringprep_utf8_to_ucs4} (const char * @var{str}, ssize_t @var{len}, size_t * @var{items_written})
@var{str}: a UTF-8 encoded string

@var{len}: the maximum length of @code{str} to use. If @code{len} < 0, then
the string is nul-terminated.

@var{items_written}: location to store the number of characters in the
result, or @code{NULL}.

Convert a string from UTF-8 to a 32-bit fixed width
representation as UCS-4, assuming valid UTF-8 input.
This function does no error checking on the input.

@strong{Return value:} a pointer to a newly allocated UCS-4 string.
This value must be deallocated by the caller.
@end deftypefun

@subheading stringprep_ucs4_to_utf8
@anchor{stringprep_ucs4_to_utf8}
@deftypefun {char *} {stringprep_ucs4_to_utf8} (const uint32_t * @var{str}, ssize_t @var{len}, size_t * @var{items_read}, size_t * @var{items_written})
@var{str}: a UCS-4 encoded string

@var{len}: the maximum length of @code{str} to use. If @code{len} < 0, then
the string is terminated with a 0 character.

@var{items_read}: location to store number of characters read read, or @code{NULL}.

@var{items_written}: location to store number of bytes written or @code{NULL}.
The value here stored does not include the trailing 0
byte.

Convert a string from a 32-bit fixed width representation as UCS-4.
to UTF-8. The result will be terminated with a 0 byte.

@strong{Return value:} a pointer to a newly allocated UTF-8 string.
This value must be deallocated by the caller.
If an error occurs, @code{NULL} will be returned and @code{error}
set.
@end deftypefun

@subheading stringprep_utf8_nfkc_normalize
@anchor{stringprep_utf8_nfkc_normalize}
@deftypefun {char *} {stringprep_utf8_nfkc_normalize} (const char * @var{str}, ssize_t @var{len})
@var{str}: a UTF-8 encoded string.

@var{len}: length of @code{str}, in bytes, or -1 if @code{str} is nul-terminated.

Converts a string into canonical form, standardizing
such issues as whether a character with an accent
is represented as a base character and combining
accent or as a single precomposed character.

The normalization mode is NFKC (ALL COMPOSE).  It standardizes
differences that do not affect the text content, such as the
above-mentioned accent representation. It standardizes the
"compatibility" characters in Unicode, such as SUPERSCRIPT THREE to
the standard forms (in this case DIGIT THREE). Formatting
information may be lost but for most text operations such
characters should be considered the same. It returns a result with
composed forms rather than a maximally decomposed form.

@strong{Return value:} a newly allocated string, that is the
NFKC normalized form of @code{str}.
@end deftypefun

@subheading stringprep_ucs4_nfkc_normalize
@anchor{stringprep_ucs4_nfkc_normalize}
@deftypefun {uint32_t *} {stringprep_ucs4_nfkc_normalize} (uint32_t * @var{str}, ssize_t @var{len})
@var{str}: a Unicode string.

@var{len}: length of @code{str} array, or -1 if @code{str} is nul-terminated.

Converts UCS4 string into UTF-8 and runs
@code{stringprep_utf8_nfkc_normalize()}.

@strong{Return value:} a newly allocated Unicode string, that is the NFKC
normalized form of @code{str}.
@end deftypefun

