/* * This is an implementation of wcwidth() and wcswidth() (defined in * IEEE Std 1002.1-2001) for Unicode. * * http://www.opengroup.org/onlinepubs/007904975/functions/wcwidth.html * http://www.opengroup.org/onlinepubs/007904975/functions/wcswidth.html * * In fixed-width output devices, Latin characters all occupy a single * "cell" position of equal width, whereas ideographic CJK characters * occupy two such cells. Interoperability between terminal-line * applications and (teletype-style) character terminals using the * UTF-8 encoding requires agreement on which character should advance * the cursor by how many cell positions. No established formal * standards exist at present on which Unicode character shall occupy * how many cell positions on character terminals. These routines are * a first attempt of defining such behavior based on simple rules * applied to data provided by the Unicode Consortium. * * For some graphical characters, the Unicode standard explicitly * defines a character-cell width via the definition of the East Asian * FullWidth (F), Wide (W), Half-width (H), and Narrow (Na) classes. * In all these cases, there is no ambiguity about which width a * terminal shall use. For characters in the East Asian Ambiguous (A) * class, the width choice depends purely on a preference of backward * compatibility with either historic CJK or Western practice. * Choosing single-width for these characters is easy to justify as * the appropriate long-term solution, as the CJK practice of * displaying these characters as double-width comes from historic * implementation simplicity (8-bit encoded characters were displayed * single-width and 16-bit ones double-width, even for Greek, * Cyrillic, etc.) and not any typographic considerations. * * Much less clear is the choice of width for the Not East Asian * (Neutral) class. Existing practice does not dictate a width for any * of these characters. It would nevertheless make sense * typographically to allocate two character cells to characters such * as for instance EM SPACE or VOLUME INTEGRAL, which cannot be * represented adequately with a single-width glyph. The following * routines at present merely assign a single-cell width to all * neutral characters, in the interest of simplicity. This is not * entirely satisfactory and should be reconsidered before * establishing a formal standard in this area. At the moment, the * decision which Not East Asian (Neutral) characters should be * represented by double-width glyphs cannot yet be answered by * applying a simple rule from the Unicode database content. Setting * up a proper standard for the behavior of UTF-8 character terminals * will require a careful analysis not only of each Unicode character, * but also of each presentation form, something the author of these * routines has avoided to do so far. * * http://www.unicode.org/unicode/reports/tr11/ * * Markus Kuhn -- 2007-05-26 (Unicode 5.0) * * Permission to use, copy, modify, and distribute this software * for any purpose and without fee is hereby granted. The author * disclaims all warranties with regard to this software. * * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c */ /* * Respnosible party: Jeremy Nelson at EPIC Software Labs (2014-01-30). * Any changes I made are donated to the public domain. */ #include "irc.h" #include "ircaux.h" #include "output.h" struct interval { int first; int last; }; /* auxiliary function for binary search in interval table */ static int bisearch (int ucs, const struct interval *table, int max) { int min = 0; int mid; if (ucs < table[0].first || ucs > table[max].last) return 0; while (max >= min) { mid = (min + max) / 2; if (ucs > table[mid].last) min = mid + 1; else if (ucs < table[mid].first) max = mid - 1; else return 1; } return 0; } /* The following two functions define the column width of an ISO 10646 * character as follows: * * - The null character (U+0000) has a column width of 0. * * - Other C0/C1 control characters and DEL will lead to a return * value of -1. * * - Non-spacing and enclosing combining characters (general * category code Mn or Me in the Unicode database) have a * column width of 0. * * - SOFT HYPHEN (U+00AD) has a column width of 1. * * - Other format characters (general category code Cf in the Unicode * database) and ZERO WIDTH SPACE (U+200B) have a column width of 0. * * - Hangul Jamo medial vowels and final consonants (U+1160-U+11FF) * have a column width of 0. * * - Spacing characters in the East Asian Wide (W) or East Asian * Full-width (F) category as defined in Unicode Technical * Report #11 have a column width of 2. * * - All remaining characters (including all printable * ISO 8859-1 and WGL4 characters, Unicode control characters, * etc.) have a column width of 1. * * This implementation assumes that (int) characters are encoded * in ISO 10646. */ int codepoint_numcolumns (int ucs) { int retval; /* sorted list of non-overlapping intervals of non-spacing characters */ /* generated by "uniset +cat=Me +cat=Mn +cat=Cf -00AD +1160-11FF +200B c" */ static const struct interval combining[] = { { 0x0300, 0x036F }, { 0x0483, 0x0486 }, { 0x0488, 0x0489 }, { 0x0591, 0x05BD }, { 0x05BF, 0x05BF }, { 0x05C1, 0x05C2 }, { 0x05C4, 0x05C5 }, { 0x05C7, 0x05C7 }, { 0x0600, 0x0603 }, { 0x0610, 0x0615 }, { 0x064B, 0x065E }, { 0x0670, 0x0670 }, { 0x06D6, 0x06E4 }, { 0x06E7, 0x06E8 }, { 0x06EA, 0x06ED }, { 0x070F, 0x070F }, { 0x0711, 0x0711 }, { 0x0730, 0x074A }, { 0x07A6, 0x07B0 }, { 0x07EB, 0x07F3 }, { 0x0901, 0x0902 }, { 0x093C, 0x093C }, { 0x0941, 0x0948 }, { 0x094D, 0x094D }, { 0x0951, 0x0954 }, { 0x0962, 0x0963 }, { 0x0981, 0x0981 }, { 0x09BC, 0x09BC }, { 0x09C1, 0x09C4 }, { 0x09CD, 0x09CD }, { 0x09E2, 0x09E3 }, { 0x0A01, 0x0A02 }, { 0x0A3C, 0x0A3C }, { 0x0A41, 0x0A42 }, { 0x0A47, 0x0A48 }, { 0x0A4B, 0x0A4D }, { 0x0A70, 0x0A71 }, { 0x0A81, 0x0A82 }, { 0x0ABC, 0x0ABC }, { 0x0AC1, 0x0AC5 }, { 0x0AC7, 0x0AC8 }, { 0x0ACD, 0x0ACD }, { 0x0AE2, 0x0AE3 }, { 0x0B01, 0x0B01 }, { 0x0B3C, 0x0B3C }, { 0x0B3F, 0x0B3F }, { 0x0B41, 0x0B43 }, { 0x0B4D, 0x0B4D }, { 0x0B56, 0x0B56 }, { 0x0B82, 0x0B82 }, { 0x0BC0, 0x0BC0 }, { 0x0BCD, 0x0BCD }, { 0x0C3E, 0x0C40 }, { 0x0C46, 0x0C48 }, { 0x0C4A, 0x0C4D }, { 0x0C55, 0x0C56 }, { 0x0CBC, 0x0CBC }, { 0x0CBF, 0x0CBF }, { 0x0CC6, 0x0CC6 }, { 0x0CCC, 0x0CCD }, { 0x0CE2, 0x0CE3 }, { 0x0D41, 0x0D43 }, { 0x0D4D, 0x0D4D }, { 0x0DCA, 0x0DCA }, { 0x0DD2, 0x0DD4 }, { 0x0DD6, 0x0DD6 }, { 0x0E31, 0x0E31 }, { 0x0E34, 0x0E3A }, { 0x0E47, 0x0E4E }, { 0x0EB1, 0x0EB1 }, { 0x0EB4, 0x0EB9 }, { 0x0EBB, 0x0EBC }, { 0x0EC8, 0x0ECD }, { 0x0F18, 0x0F19 }, { 0x0F35, 0x0F35 }, { 0x0F37, 0x0F37 }, { 0x0F39, 0x0F39 }, { 0x0F71, 0x0F7E }, { 0x0F80, 0x0F84 }, { 0x0F86, 0x0F87 }, { 0x0F90, 0x0F97 }, { 0x0F99, 0x0FBC }, { 0x0FC6, 0x0FC6 }, { 0x102D, 0x1030 }, { 0x1032, 0x1032 }, { 0x1036, 0x1037 }, { 0x1039, 0x1039 }, { 0x1058, 0x1059 }, { 0x1160, 0x11FF }, { 0x135F, 0x135F }, { 0x1712, 0x1714 }, { 0x1732, 0x1734 }, { 0x1752, 0x1753 }, { 0x1772, 0x1773 }, { 0x17B4, 0x17B5 }, { 0x17B7, 0x17BD }, { 0x17C6, 0x17C6 }, { 0x17C9, 0x17D3 }, { 0x17DD, 0x17DD }, { 0x180B, 0x180D }, { 0x18A9, 0x18A9 }, { 0x1920, 0x1922 }, { 0x1927, 0x1928 }, { 0x1932, 0x1932 }, { 0x1939, 0x193B }, { 0x1A17, 0x1A18 }, { 0x1B00, 0x1B03 }, { 0x1B34, 0x1B34 }, { 0x1B36, 0x1B3A }, { 0x1B3C, 0x1B3C }, { 0x1B42, 0x1B42 }, { 0x1B6B, 0x1B73 }, { 0x1DC0, 0x1DCA }, { 0x1DFE, 0x1DFF }, { 0x200B, 0x200F }, { 0x202A, 0x202E }, { 0x2060, 0x2063 }, { 0x206A, 0x206F }, { 0x20D0, 0x20EF }, { 0x302A, 0x302F }, { 0x3099, 0x309A }, { 0xA806, 0xA806 }, { 0xA80B, 0xA80B }, { 0xA825, 0xA826 }, { 0xFB1E, 0xFB1E }, { 0xFE00, 0xFE0F }, { 0xFE20, 0xFE23 }, { 0xFEFF, 0xFEFF }, { 0xFFF9, 0xFFFB }, { 0x10A01, 0x10A03 }, { 0x10A05, 0x10A06 }, { 0x10A0C, 0x10A0F }, { 0x10A38, 0x10A3A }, { 0x10A3F, 0x10A3F }, { 0x1D167, 0x1D169 }, { 0x1D173, 0x1D182 }, { 0x1D185, 0x1D18B }, { 0x1D1AA, 0x1D1AD }, { 0x1D242, 0x1D244 }, { 0xE0001, 0xE0001 }, { 0xE0020, 0xE007F }, { 0xE0100, 0xE01EF } }; if (ucs == 0) return 0; /* test for C0 control chars including C1 8 bit control chars */ if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0)) return -1; /* binary search in table of non-spacing characters */ if (bisearch(ucs, combining, sizeof(combining) / sizeof(struct interval) - 1)) return 0; /* if we arrive here, ucs is not a combining or C0/C1 control character */ retval = 1 + (ucs >= 0x1100 && (ucs <= 0x115f || /* Hangul Jamo init. consonants */ ucs == 0x2329 || ucs == 0x232a || (ucs >= 0x2e80 && ucs <= 0xa4cf && ucs != 0x303f) || /* CJK ... Yi */ (ucs >= 0xac00 && ucs <= 0xd7a3) || /* Hangul Syllables */ (ucs >= 0xf900 && ucs <= 0xfaff) || /* CJK Compatibility Ideographs */ (ucs >= 0xfe10 && ucs <= 0xfe19) || /* Vertical forms */ (ucs >= 0xfe30 && ucs <= 0xfe6f) || /* CJK Compatibility Forms */ (ucs >= 0xff00 && ucs <= 0xff60) || /* Fullwidth Forms */ (ucs >= 0xffe0 && ucs <= 0xffe6) || (ucs >= 0x1f300 && ucs <= 0x1f6ff) || /* Emojis, unicode 6 */ (ucs >= 0x20000 && ucs <= 0x2fffd) || (ucs >= 0x30000 && ucs <= 0x3fffd))); return retval; } /* *** ADDED STUFF - NOT IN ORIGINAL *** */ int next_code_point2 (const char *i_, ptrdiff_t *bytes_used, int resync) { unsigned char a, b, c, d; const char * i = i_; const char * str; int result; if (!i_) return 0; /* What is this? */ /* Keep skipping bytes until we find one that works */ for (; *i; i++) { str = i; a = b = c = d = 0; result = -1; /* Forcibly refuse to walk past the nul */ if (str[0] == 0) return 0; if (str[0]) { a = (unsigned char)str[0]; if (str[1]) { b = (unsigned char)str[1]; if (str[2]) { c = (unsigned char)str[2]; if (str[3]) d = (unsigned char)str[3]; } } } if ((a & 0x80) == 0x00) { result = a; i++; } /* The 2 high bits are set only? -- 2 bytes */ if ((a & 0xE0) == 0xC0) { if ((b & 0xC0) == 0x80) { result = ((a & 0x1F) << 6) + (b & 0x3f); i += 2; } } /* The 3 high bits are set only? -- 3 bytes */ else if ((a & 0xF0) == 0xE0) { if ((b & 0xC0) == 0x80) { if ((c & 0xC0) == 0x80) { result = ((a & 0x0F) << 12) + ((b & 0x3f) << 6) + (c & 0x3f); i += 3; } } } /* The 4 high bits are set only? -- 4 bytes*/ else if ((a & 0xF8) == 0xF0) { if ((b & 0xC0) == 0x80) { if ((c & 0xC0) == 0x80) { if ((d & 0xC0) == 0x80) { result = ((a & 0x07) << 18) + ((b & 0x3f) << 12) + ((c & 0x3f) << 6) + (d & 0x3F); i += 4; } } } } /* If result is -1, something is wrong */ if (result == -1) { if (resync) continue; } *bytes_used = i - i_; return result; } /* If we hit the end of the string, return nul */ *bytes_used = i - i_; return 0; } /* * partial_code_point -- Tell me why 'i' is not a valid utf8 sequence * * Arguments: * i - A pointer to a string rejected by next_code_point() * * Return value: * 1 - The string 'i' points at a utf8 sequence that appears * to be valid, but truncated. * 0 - I don't see anything wrong with 'i' * -1 - 'i' does not point at a valid utf8 sequence at all. */ int partial_code_point (const char *i_) { const char *i = i_; unsigned char a, b, c, d; const char *str; str = i; a = b = c = d = 0; if (str[0]) { a = (unsigned char)str[0]; if (str[1]) { b = (unsigned char)str[1]; if (str[2]) { c = (unsigned char)str[2]; if (str[3]) d = (unsigned char)str[3]; } } } /* A 7 bit char is not a partial incomplete sequence */ if ((a & 0x80) == 0x00) return 0; /* The 2 high bits are set only? -- 2 bytes */ if ((a & 0xE0) == 0xC0) { /* if b is a nul, then it is truncated */ if (b == 0) return 1; /* If it's valid, ok. */ else if ((b & 0xC0) == 0x80) return 0; /* This is just garbage */ else return -1; } /* The 3 high bits are set only? -- 3 bytes */ else if ((a & 0xF0) == 0xE0) { /* If b is a null, it is truncated */ if (b == 0) return 1; /* Otherwise, if 'b' is a valid next char... */ else if ((b & 0xC0) == 0x80) { /* If c is a null, it is truncated */ if (c == 0) return 1; /* Or, if c is a valid final char... */ else if ((c & 0xC0) == 0x80) return 0; /* Otherwise, c is just garbage */ else return -1; } /* Otherwise, 'b' is just garbage */ else return -1; } /* The 4 high bits are set only? -- 4 bytes*/ else if ((a & 0xF8) == 0xF0) { if (b == 0) return 1; /* Otherwise, if 'b' is a valid next char... */ else if ((b & 0xC0) == 0x80) { /* If c is a null, it is truncated */ if (c == 0) return 1; /* Or, if c is a valid next char... */ else if ((c & 0xC0) == 0x80) { if (d == 0) return 1; else if ((d & 0xC0) == 0x80) return 0; else return -1; } /* Otherwise, c is just garbage */ else return -1; } else return -1; } return -1; } int grab_codepoint (const char *x) { ptrdiff_t offset; return next_code_point2(x, &offset, 1); } /* * quick_display_column_count - How many columns would 'str' take up? * * Arguments: * str - A UTF-8 string * * Return Value: * The number of columns 'str' would take up. * * IMPORTANT NOTE! * This function does NOT properly handle attribute markers that * take following characters (^C, ^X). Whereas it properly ignores * things like ^V, ^B, ^C02 would result in "2" rather than "0". * * The correct way to get column counts is found in * ircaux.c:fix_string_width(), which involves using * new_normalize_string() and output_with_count(). */ /* XXX DO NOT USE THIS FUNCTION IF 'str' MIGHT CONTAIN HIGHLIGHT CHARS! XXX */ int quick_display_column_count (const char *str) { const char *s; int code_point; int length = 0; int x; ptrdiff_t offset; s = str; while ((code_point = next_code_point2(s, &offset, 1))) { s += offset; if ((x = codepoint_numcolumns(code_point)) == -1) x = 0; length += x; } return length; } /* * count_initial_codepoints - How many codepoints in 'str' before 'p'? * * Arguments: * str - A UTF-8 string * p - A character pointer somewhere inside 'str' * * Return Value: * The number of codepoints in 'str' before 'p' * ie, $mid(X 999 $str) == $p * * IMPORTANT NOTE! * This is used by $regmatches() to convert a pointer to something * that you can pass to $mid(). */ int count_initial_codepoints (const char *str, const char *p) { const char *s; int length = 0; ptrdiff_t offset; if (str >= p) return 0; s = str; while (next_code_point2(s, &offset, 1)) { s += offset; length++; if (s >= p) return length; } /* * This is only reached if 'p' is not in 'str'. * In this case, I decided it's better to point at * the end ofo the string, which yields a zero-length * string. I'm not positive this is the right call */ return length; } int input_column_count (const char *str) { const char *s; int code_point; int length = 0; int x; ptrdiff_t offset; s = str; while ((code_point = next_code_point2(s, &offset, 1))) { s += offset; if ((x = codepoint_numcolumns(code_point)) == -1) x = 1; length += x; } return length; } /* * This does a QUICK code point count. * Every code point contains one (and only one) byte in the range: * 0x00-0x7F * 0xC0-0xFF * This function doesn't attempt to validate broken utf8. */ int quick_code_point_count (const char *str) { const char *s; int count; for (count = 0, s = str; *s; s++) { if ((unsigned char)*s < 0x80 || (unsigned char)*s >= 0xC0) count++; } return count; } /* * previous_code_point - Move *i back one code point. * *** IMPORTANT *** * This is technically a "quick" function since it * does not validate the string is well formed utf8. * * Arguments: * st The first byte of whatever string 'i' is pointing to. * i A pointer to the start of a CP. * * Return Value: * - If 'i' points at the first byte of a code point, then * the code point that ends at the byte i - 1. * - If 'i' does not point at the first byte of a code point, * then the code that that contains 'i'. * - If 'i' points at the start of string (st), returns 0 so you can stop. * *offset will be set to first byte of the code point whose value is returned. * * If the previous code point is invalid (next_code_point2() returns -1) * then it will skip that invalid code point and keep walking backwards. */ int previous_code_point2 (const char *st, const char *i, ptrdiff_t *offset) { const char * c; int retval; ptrdiff_t offset2; c = i; for (;;) { if (c == st) { *offset = 0; return 0; /* Time to stop */ } if (c > st && ((unsigned char)*c < 0x80 || (unsigned char)*c >= 0xC0)) c--; while (c > st && ((unsigned char)*c >= 0x80 && (unsigned char)*c < 0xC0)) c--; if ((retval = next_code_point2(c, &offset2, 0)) >= 0) { *offset = c - i; return retval; } } } /* * This does a QUICK count of the CP "index" of 'loc' in 'str'. */ int quick_code_point_index (const char *str, const char *loc) { const char *s; int count; for (count = 0, s = str; *s && s < loc; s++) { if ((unsigned char)*s < 0x80 || (unsigned char)*s >= 0xC0) count++; } return count; }