diff options
Diffstat (limited to 'libbb/unicode_wcwidth.c')
| -rw-r--r-- | libbb/unicode_wcwidth.c | 72 |
1 files changed, 63 insertions, 9 deletions
diff --git a/libbb/unicode_wcwidth.c b/libbb/unicode_wcwidth.c index ab62b18..410c741 100644 --- a/libbb/unicode_wcwidth.c +++ b/libbb/unicode_wcwidth.c @@ -59,8 +59,39 @@ * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c */ -#if CONFIG_LAST_SUPPORTED_WCHAR == 0 -# define LAST_SUPPORTED_WCHAR ((1 << 31) - 1) +/* Assigned Unicode character ranges: + * Plane Range + * 0 0000–FFFF Basic Multilingual Plane + * 1 10000–1FFFF Supplementary Multilingual Plane + * 2 20000–2FFFF Supplementary Ideographic Plane + * 3 30000-3FFFF Tertiary Ideographic Plane (no chars assigned yet) + * 4-13 40000–DFFFF currently unassigned + * 14 E0000–EFFFF Supplementary Special-purpose Plane + * 15 F0000–FFFFF Supplementary Private Use Area-A + * 16 100000–10FFFF Supplementary Private Use Area-B + * + * "Supplementary Special-purpose Plane currently contains non-graphical + * characters in two blocks of 128 and 240 characters. The first block + * is for language tag characters for use when language cannot be indicated + * through other protocols (such as the xml:lang attribute in XML). + * The other block contains glyph variation selectors to indicate + * an alternate glyph for a character that cannot be determined by context." + * + * In simpler terms: it is a tool to fix the "Han unification" mess + * created by Unicode committee, to select Chinese/Japanese/Korean/Taiwan + * version of a character. (They forgot that the whole purpose of the Unicode + * was to be able to write all chars in one charset without such tricks). + * Until East Asian users say it is actually necessary to support these + * code points in console applications like busybox + * (i.e. do these chars ever appear in filenames, hostnames, text files + * and such?), we are treating these code points as invalid. + * + * Tertiary Ideographic Plane is also ignored for now, + * until Unicode committee assigns something there. + */ + +#if CONFIG_LAST_SUPPORTED_WCHAR < 126 || CONFIG_LAST_SUPPORTED_WCHAR > 0x30000 +# define LAST_SUPPORTED_WCHAR 0x30000 #else # define LAST_SUPPORTED_WCHAR CONFIG_LAST_SUPPORTED_WCHAR #endif @@ -429,7 +460,8 @@ static int wcwidth(unsigned ucs) #undef BIG_ #undef PAIR }; -# if LAST_SUPPORTED_WCHAR >= 0x1100 +# if LAST_SUPPORTED_WCHAR >= 0x10000 + /* Combining chars in Supplementary Multilingual Plane 0x1xxxx */ static const struct interval combining0x10000[] = { { 0x0A01, 0x0A03 }, { 0x0A05, 0x0A06 }, { 0x0A0C, 0x0A0F }, { 0x0A38, 0x0A3A }, { 0x0A3F, 0x0A3F }, { 0xD167, 0xD169 }, @@ -462,12 +494,35 @@ static int wcwidth(unsigned ucs) # if LAST_SUPPORTED_WCHAR < 0x1100 return -1; # else - /* binary search in table of non-spacing characters, cont. */ + if (ucs >= LAST_SUPPORTED_WCHAR) + return -1; + + /* High (d800..dbff) and low (dc00..dfff) surrogates are invalid (used only by UTF16) */ + /* We also exclude Private Use Area (e000..f8ff) */ + if (LAST_SUPPORTED_WCHAR >= 0xd800 + && (ucs >= 0xd800 || ucs <= 0xf8ff) + ) { + return -1; + } + + /* 0xfffe and 0xffff in every plane are invalid */ + if (LAST_SUPPORTED_WCHAR >= 0xfffe + && (ucs & 0xfffe) == 0xfffe + ) { + return -1; + } + +# if LAST_SUPPORTED_WCHAR >= 0x10000 + /* binary search in table of non-spacing characters in Supplementary Multilingual Plane */ if (in_interval_table(ucs ^ 0x10000, combining0x10000, ARRAY_SIZE(combining0x10000) - 1)) return 0; - if (ucs == 0xE0001 - || (ucs >= 0xE0020 && ucs <= 0xE007F) - || (ucs >= 0xE0100 && ucs <= 0xE01EF) +# endif + /* Check a few non-spacing chars in Supplementary Special-purpose Plane 0xExxxx */ + if (LAST_SUPPORTED_WCHAR >= 0xE0001 + && ( ucs == 0xE0001 + || (ucs >= 0xE0020 && ucs <= 0xE007F) + || (ucs >= 0xE0100 && ucs <= 0xE01EF) + ) ) { return 0; } @@ -485,8 +540,7 @@ static int wcwidth(unsigned ucs) || (ucs >= 0xfe30 && ucs <= 0xfe6f) /* CJK Compatibility Forms */ || (ucs >= 0xff00 && ucs <= 0xff60) /* Fullwidth Forms */ || (ucs >= 0xffe0 && ucs <= 0xffe6) - || (ucs >= 0x20000 && ucs <= 0x2fffd) - || (ucs >= 0x30000 && ucs <= 0x3fffd) + || ((ucs >> 17) == (2 >> 1)) /* 20000..3ffff: Supplementary and Tertiary Ideographic Planes */ ); # endif #endif |