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Diffstat (limited to 'lout/unicode.cc')
| -rw-r--r-- | lout/unicode.cc | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/lout/unicode.cc b/lout/unicode.cc new file mode 100644 index 0000000..da9c27a --- /dev/null +++ b/lout/unicode.cc @@ -0,0 +1,190 @@ +/* + * RTFL (originally part of dillo) + * + * Copyright 2012, 2013 Sebastian Geerken <sgeerken@dillo.org> + * + * 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; with the following exception: + * + * The copyright holders of RTFL give you permission to link this file + * statically or dynamically against all versions of the graphviz + * library, which are published by AT&T Corp. under one of the following + * licenses: + * + * - Common Public License version 1.0 as published by International + * Business Machines Corporation (IBM), or + * - Eclipse Public License version 1.0 as published by the Eclipse + * Foundation. + * + * 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 <http://www.gnu.org/licenses/>. + */ + + +#include "unicode.hh" +#include "misc.hh" + +using namespace lout::misc; + +namespace lout { + +namespace unicode { + +static unsigned char alpha[0x500] = { + // 0000-007F: C0 Controls and Basic Latin + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0xfe, 0xff, 0xff, 0x07, 0xfe, 0xff, 0xff, 0x07, + // 0080-00FF: C1 Controls and Latin-1 Supplement + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0xff, 0xff, 0x7f, 0xff, 0xff, 0xff, 0x7f, 0xff, + // 0100-017F: Latin Extended-A + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + // 0180-024F: Latin Extended-B + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xf0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, + // 0250–02AF: IPA Extensions + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + // 02B0–02FF: Spacing Modifier Letters + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, + // 0300–036F: Combining Diacritical Marks + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + // 0370–03FF: Greek and Coptic + 0xcf, 0x00, 0x40, 0x7d, 0xff, 0xff, 0xfb, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + // 0400–04FF: Cyrillic + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0x03, 0xfc, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff +}; + +/** + * Returns whether a given unicode character is an alphabetic character. + */ +bool isAlpha (int ch) +{ + return ch < 0x500 && (alpha[ch / 8] & (1 << (ch & 7))); +} + +int decodeUtf8 (const char *s) +{ + if((s[0] & 0x80) == 0) + return s[0]; + else if((s[0] & 0xe0) == 0xc0 && (s[1] & 0xc0) == 0x80) + return ((s[0] & 0x1f) << 6) | (s[1] & 0x3f); + else if((s[0] & 0xf0) == 0xe0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80) + return ((s[0] & 0x0f) << 12) | ((s[1] & 0x3f) << 6) | (s[2] & 0x3f); + else if((s[0] & 0xf8) == 0xf0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80 && (s[3] & 0xc0) == 0x80) + return ((s[0] & 0x0f) << 18) | ((s[1] & 0x3f) << 12) + | ((s[2] & 0x3f) << 6) | (s[3] & 0x3f); + else + // Treat as ISO-8859-1 / ISO-8859-15 / Windows-1252 + return s[0]; +} + + +int decodeUtf8 (const char *s, int len) +{ + if(len >= 1 && (s[0] & 0x80) == 0) + return s[0]; + else if(len >= 2 && (s[0] & 0xe0) == 0xc0 && (s[1] & 0xc0) == 0x80) + return ((s[0] & 0x1f) << 6) | (s[1] & 0x3f); + else if(len >= 3 && (s[0] & 0xf0) == 0xe0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80) + return ((s[0] & 0x0f) << 12) | ((s[1] & 0x3f) << 6) | (s[2] & 0x3f); + else if(len >= 4 && (s[0] & 0xf8) == 0xf0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80 && (s[3] & 0xc0) == 0x80) + return ((s[0] & 0x0f) << 18) | ((s[1] & 0x3f) << 12) + | ((s[2] & 0x3f) << 6) | (s[3] & 0x3f); + else + // Treat as ISO-8859-1 / ISO-8859-15 / Windows-1252 + return s[0]; +} + +const char *nextUtf8Char (const char *s) +{ + const char *r; + + if (s == NULL || s[0] == 0) + r = NULL; + else if((s[0] & 0x80) == 0) + r = s + 1; + else if((s[0] & 0xe0) == 0xc0 && (s[1] & 0xc0) == 0x80) + r = s + 2; + else if((s[0] & 0xf0) == 0xe0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80) + r = s + 3; + else if((s[0] & 0xf8) == 0xf0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80 && (s[3] & 0xc0) == 0x80) + r = s + 4; + else + // invalid UTF-8 sequence: treat as one byte. + r = s + 1; + + if (r && r[0] == 0) + return NULL; + else + return r; +} + +const char *nextUtf8Char (const char *s, int len) +{ + const char *r; + + if (s == NULL || len <= 0) + r = NULL; + else if(len >= 1 && (s[0] & 0x80) == 0) + r = s + 1; + else if(len >= 2 && (s[0] & 0xe0) == 0xc0 && (s[1] & 0xc0) == 0x80) + r = s + 2; + else if(len >= 3 && (s[0] & 0xf0) == 0xe0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80) + r = s + 3; + else if(len >= 4 && (s[0] & 0xf8) == 0xf0 && (s[1] & 0xc0) == 0x80 + && (s[2] & 0xc0) == 0x80 && (s[3] & 0xc0) == 0x80) + r = s + 4; + else + // invalid UTF-8 sequence: treat as one byte. + r = s + 1; + + if (r && r - s >= len) + return NULL; + else + return r; +} + +int numUtf8Chars (const char *s) +{ + int numUtf8 = 0; + for (const char *r = s; r; r = nextUtf8Char (r)) + numUtf8++; + return numUtf8; +} + +int numUtf8Chars (const char *s, int len) +{ + int numUtf8 = 0; + for (const char *r = s; len > 0 && r; r = nextUtf8Char (r, len)) + numUtf8++; + return numUtf8; +} + +} // namespace lout + +} // namespace unicode |