1 /* Determine the number of screen columns needed for a character. 2 Copyright (C) 2006-2007, 2010-2012 Free Software Foundation, Inc. 3 4 This program is free software: you can redistribute it and/or modify 5 it under the terms of the GNU General Public License as published by 6 the Free Software Foundation; either version 3 of the License, or 7 (at your option) any later version. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 16 17 #include <config.h> 18 19 /* Specification. */ 20 #include <wchar.h> 21 22 /* Get iswprint. */ 23 #include <wctype.h> 24 25 #include "localcharset.h" 26 #include "streq.h" 27 #include "uniwidth.h" 28 29 int 30 wcwidth (wchar_t wc) 31 #undef wcwidth 32 { 33 /* In UTF-8 locales, use a Unicode aware width function. */ 34 const char *encoding = locale_charset (); 35 if (STREQ_OPT (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0 ,0)) 36 { 37 /* We assume that in a UTF-8 locale, a wide character is the same as a 38 Unicode character. */ 39 return uc_width (wc, encoding); 40 } 41 else 42 { 43 /* Otherwise, fall back to the system's wcwidth function. */ 44 #if HAVE_WCWIDTH 45 return wcwidth (wc); 46 #else 47 return wc == 0 ? 0 : iswprint (wc) ? 1 : -1; 48 #endif 49 } 50 } 51