newlib: wide char support

git-svn-id: svn://kolibrios.org@6607 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/newlib/libc/stdlib/wctomb.c

@@ -0,0 +1,81 @@
+/*
+FUNCTION
+<<wctomb>>---minimal wide char to multibyte converter
+
+INDEX
+	wctomb
+
+ANSI_SYNOPSIS
+	#include <stdlib.h>
+	int wctomb(char *<[s]>, wchar_t <[wchar]>);
+
+TRAD_SYNOPSIS
+	#include <stdlib.h>
+	int wctomb(<[s]>, <[wchar]>)
+	char *<[s]>;
+	wchar_t <[wchar]>;
+
+DESCRIPTION
+When _MB_CAPABLE is not defined, this is a minimal ANSI-conforming 
+implementation of <<wctomb>>.  The
+only ``wide characters'' recognized are single bytes,
+and they are ``converted'' to themselves.  
+
+When _MB_CAPABLE is defined, this routine calls <<_wctomb_r>> to perform
+the conversion, passing a state variable to allow state dependent
+decoding.  The result is based on the locale setting which may
+be restricted to a defined set of locales.
+
+Each call to <<wctomb>> modifies <<*<[s]>>> unless <[s]> is a null
+pointer or _MB_CAPABLE is defined and <[wchar]> is invalid.
+
+RETURNS
+This implementation of <<wctomb>> returns <<0>> if
+<[s]> is <<NULL>>; it returns <<-1>> if _MB_CAPABLE is enabled
+and the wchar is not a valid multi-byte character, it returns <<1>>
+if _MB_CAPABLE is not defined or the wchar is in reality a single
+byte character, otherwise it returns the number of bytes in the
+multi-byte character.
+
+PORTABILITY
+<<wctomb>> is required in the ANSI C standard.  However, the precise
+effects vary with the locale.
+
+<<wctomb>> requires no supporting OS subroutines.
+*/
+
+#ifndef _REENT_ONLY
+
+#include <newlib.h>
+#include <stdlib.h>
+#include <errno.h>
+#include "local.h"
+
+int
+_DEFUN (wctomb, (s, wchar),
+        char *s _AND
+        wchar_t wchar)
+{
+#ifdef _MB_CAPABLE
+	struct _reent *reent = _REENT;
+
+        _REENT_CHECK_MISC(reent);
+
+        return __wctomb (reent, s, wchar, __locale_charset (),
+			 &(_REENT_WCTOMB_STATE(reent)));
+#else /* not _MB_CAPABLE */
+        if (s == NULL)
+                return 0;
+
+	/* Verify that wchar is a valid single-byte character.  */
+	if ((size_t)wchar >= 0x100) {
+		errno = EILSEQ;
+		return -1;
+	}
+
+        *s = (char) wchar;
+        return 1;
+#endif /* not _MB_CAPABLE */
+}
+
+#endif /* !_REENT_ONLY */