Combining characters not applied to fullwidth characters

[Gavin Troy]

Hi,

It would seem combining characters are not correctly applied to fullwidth 
characters when using the likes of addstr (or addwstr). From a glance at the 
source it seems it is added to x-1 when it would need to be applied to x-2 for 
this case.

Example follows below using the following characters (although this selection 
is arbitrary).
U+30BB (KATAKANA LETTER SE)
U+3099 (COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK)

This prints as セ rather than ゼ.

Gavin


#include <locale.h>
#include <curses.h>

int main (int argc, char *argv[]) {
  setlocale(LC_CTYPE, "");

  initscr();
  addstr("\xe3\x82\xbb\xe3\x82\x99\n");
  clrtoeol();
  getch();
  endwin();

  return 0;
}