newlib: wide char support

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

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

@@ -0,0 +1,77 @@
+/*
+FUNCTION
+<<_mblen_r>>---reentrant minimal multibyte length function
+
+INDEX
+	_mblen_r
+
+ANSI_SYNOPSIS
+	#include <stdlib.h>
+	int _mblen_r(struct _reent *<[r]>, const char *<[s]>, size_t <[n]>, int *<[state]>);
+
+TRAD_SYNOPSIS
+	#include <stdlib.h>
+	int _mblen_r(<[r]>, <[s]>, <[n]>, <[state]>)
+        struct _reent *<[r]>;
+	const char *<[s]>;
+	size_t <[n]>;
+        int *<[state]>;
+
+DESCRIPTION
+When _MB_CAPABLE is not defined, this is a minimal ANSI-conforming 
+implementation of <<_mblen_r>>.  In this case, the
+only ``multi-byte character sequences'' recognized are single bytes,
+and thus <<1>> is returned unless <[s]> is the null pointer or
+has a length of 0 or is the empty string.
+
+When _MB_CAPABLE is defined, this routine calls <<_mbtowc_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.
+
+RETURNS
+This implementation of <<_mblen_r>> returns <<0>> if
+<[s]> is <<NULL>> or the empty string; it returns <<1>> if not _MB_CAPABLE or
+the character is a single-byte character; it returns <<-1>>
+if the multi-byte character is invalid; otherwise it returns
+the number of bytes in the multibyte character.
+
+PORTABILITY
+<<_mblen>> is required in the ANSI C standard.  However, the precise
+effects vary with the locale.
+
+<<_mblen_r>> requires no supporting OS subroutines.
+*/
+
+#include <newlib.h>
+#include <stdlib.h>
+#include <wchar.h>
+#include "local.h"
+
+int
+_DEFUN (_mblen_r, (r, s, n, state), 
+        struct _reent *r    _AND
+        const char *s _AND
+        size_t n _AND
+        mbstate_t *state)
+{
+#ifdef _MB_CAPABLE
+  int retval;
+  retval = __mbtowc (r, NULL, s, n, __locale_charset (), state);
+
+  if (retval < 0)
+    {
+      state->__count = 0;
+      return -1;
+    }
+
+  return retval;
+#else /* not _MB_CAPABLE */
+  if (s == NULL || *s == '\0')
+    return 0;
+  if (n == 0)
+    return -1;
+  return 1;
+#endif /* not _MB_CAPABLE */
+}
+