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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 17:39:29 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 17:39:29 +0000 |
commit | 8ffec2a3aba6f114784e11f89ef1d57a096ae540 (patch) | |
tree | ccebcbad06203e8241a8e7249f8e6c478a3682ea /lib/wcwidth.c | |
parent | Initial commit. (diff) | |
download | coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.tar.xz coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.zip |
Adding upstream version 8.32.upstream/8.32upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/wcwidth.c')
-rw-r--r-- | lib/wcwidth.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/lib/wcwidth.c b/lib/wcwidth.c new file mode 100644 index 0000000..6af212b --- /dev/null +++ b/lib/wcwidth.c @@ -0,0 +1,73 @@ +/* Determine the number of screen columns needed for a character. + Copyright (C) 2006-2007, 2010-2020 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +#include <config.h> + +/* Specification. */ +#include <wchar.h> + +/* Get iswprint. */ +#include <wctype.h> + +#include "localcharset.h" +#include "streq.h" +#include "uniwidth.h" + +/* Returns 1 if the current locale is an UTF-8 locale, 0 otherwise. */ +static inline int +is_locale_utf8 (void) +{ + const char *encoding = locale_charset (); + return STREQ_OPT (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0, 0); +} + +#if GNULIB_WCHAR_SINGLE +/* When we know that the locale does not change, provide a speedup by + caching the value of is_locale_utf8. */ +static int cached_is_locale_utf8 = -1; +static inline int +is_locale_utf8_cached (void) +{ + if (cached_is_locale_utf8 < 0) + cached_is_locale_utf8 = is_locale_utf8 (); + return cached_is_locale_utf8; +} +#else +/* By default, don't make assumptions, hence no caching. */ +# define is_locale_utf8_cached is_locale_utf8 +#endif + +int +wcwidth (wchar_t wc) +#undef wcwidth +{ + /* In UTF-8 locales, use a Unicode aware width function. */ + if (is_locale_utf8_cached ()) + { + /* We assume that in a UTF-8 locale, a wide character is the same as a + Unicode character. */ + return uc_width (wc, "UTF-8"); + } + else + { + /* Otherwise, fall back to the system's wcwidth function. */ +#if HAVE_WCWIDTH + return wcwidth (wc); +#else + return wc == 0 ? 0 : iswprint (wc) ? 1 : -1; +#endif + } +} |