* fhandler.h (fhandler_console::trunc_buf): Add to use as cache for

truncated multibyte characters on input.
	(fhandler_console::write_replacement_char): Declare new method.
	* fhandler_console.cc (CONVERT_LIMIT): Raise to 64K.
	(fhandler_console::fhandler_console): Initialize trunc_buf.
	(ERR): Define as independent value again.
	(fhandler_console::write_replacement_char): New method to print
	replacement chars.
	(fhandler_console::write_normal): Add handling for truncated multibyte
	sequences.  Call next_char instead of pathetic CharNextExA function.
	Don't change src, rather just work with found later on.
	* miscfuncs.cc (is_cp_multibyte): Move here from strfuncs.cc.
	Don't call Windows function, restrict to well-known ANSI/OEM codepages
	and UTF-8.
	(next_char): Call CharNextExA only for doublebyte codepages.
	Implement for UTF-8 here.
	* strfuncs.cc (is_cp_multibyte): Move to miscfuncs.cc.
	* winsup.h (next_char): Declare.
	* include/limits.h (MB_LEN_MAX): Set to maximum value of MB_CUR_MAX
	as defined by newlib for now.

winsup/cygwin/fhandler.h

@@ -896,6 +896,13 @@ class fhandler_console: public fhandler_termios
   static dev_console *dev_state;
   static bool invisible_console;
 
+  /* Used when we encounter a truncated multi-byte sequence.  The
+     lead bytes are stored here and revisited in the next write call. */
+  struct {
+    int len;
+    unsigned char buf[4]; /* Max len of valid UTF-8 sequence. */
+  } trunc_buf;
+
 /* Output calls */
   void set_default_attr ();
 
@@ -904,6 +911,7 @@ class fhandler_console: public fhandler_termios
   void cursor_set (bool, int, int);
   void cursor_get (int *, int *);
   void cursor_rel (int, int);
+  void write_replacement_char (const unsigned char *);
   const unsigned char *write_normal (unsigned const char*, unsigned const char *);
   void char_command (char);
   bool set_raw_win32_keyboard_mode (bool);