Implement the ISO C90 Amd.1 restartable wide and multibyte character

manipulation functions mbrlen(), mbrtowc(), mbsinit(), mbsrtowcs(),
wcrtomb(), wcsrtombs().

1 files changed, 142 insertions, 0 deletions

diff --git a/lib/libc/locale/mbrtowc.3 b/lib/libc/locale/mbrtowc.3
new file mode 100644
index 0000000..bb0f1ac
--- /dev/null
+++ b/lib/libc/locale/mbrtowc.3
@@ -0,0 +1,142 @@
+.\" Copyright (c) 2002 Tim J. Robbins
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.Dd August 15, 2002
+.Dt MBRTOWC 3
+.Os
+.Sh NAME
+.Nm mbrtowc
+.Nd "convert a character to a wide-character code (restartable)"
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In wchar.h
+.Ft size_t
+.Fn mbrtowc "wchar_t *restrict pwc" "const char *restrict s" "size_t n" "mbstate_t *restrict ps"
+.Sh DESCRIPTION
+The
+.Fn mbrtowc
+function inspects at most
+.Fa n
+bytes pointed to by
+.Fa s
+and interprets them as a multibyte character sequence
+according to the current setting of
+.Ev LC_CTYPE .
+If
+.Fa pwc
+is not
+.Dv NULL ,
+the multibyte character which
+.Fa s
+represents is stored in the
+.Ft wchar_t
+it points to.
+.Pp
+If
+.Fa s
+is
+.Dv NULL ,
+.Fn mbrtowc
+behaves as if
+.Fa pwc
+was
+.Dv NULL ,
+.Fa s
+was an empty string ("")
+and
+.Fa n
+was 1.
+.Pp
+The
+.Ft mbstate_t
+argument,
+.Fa ps ,
+is used to keep track of the shift state.
+If it is
+.Dv NULL ,
+.Fn mbrtowc
+uses an internal, static
+.Ft mbstate_t
+object.
+.Sh RETURN VALUES
+The
+.Fn mbrtowc
+functions returns:
+.Bl -tag -width indent
+.It 0
+The first
+.Fa n
+or fewer bytes of
+.Fa s
+represent the null wide character (L'\e0').
+.It >0
+The first
+.Fa n
+or fewer bytes of
+.Fa s
+represent a valid character,
+.Fn mbrtowc
+returns the length (in bytes) of the multibyte sequence.
+.It Xo
+.No ( Ns
+.Ft size_t Ns
+.No ) Ns \&-2
+.Xc
+The first
+.Fa n
+bytes of
+.Fa s
+are an incomplete multibyte sequence.
+.It Xo
+.No ( Ns
+.Ft size_t Ns
+.No ) Ns \&-1
+.Xc
+The byte sequence pointed to by
+.Fa s
+is an invalid multibyte sequence.
+.El
+.Sh ERRORS
+The
+.Fn mbrtowc
+function will fail if:
+.Bl -tag -width Er
+.\".It Bq Er EINVAL
+.\"Invalid argument.
+.It Bq Er EILSEQ
+An invalid multibyte sequence was detected.
+.El
+.Sh SEE ALSO
+.Xr mbtowc 3 ,
+.Xr setlocale 3 ,
+.Xr wcrtomb 3
+.Sh STANDARDS
+The
+.Fn mbrtowc
+function conforms to
+.St -isoC-99 .
+.Sh BUGS
+The current implementation does not support shift states.