diff options
Diffstat (limited to 'src/cairo-unicode.c')
| -rw-r--r-- | src/cairo-unicode.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/src/cairo-unicode.c b/src/cairo-unicode.c new file mode 100644 index 000000000..92201391a --- /dev/null +++ b/src/cairo-unicode.c @@ -0,0 +1,340 @@ +/* cairo_unicode.c: Unicode conversion routines + * + * The code in this file is derived from GLib's gutf8.c and + * ultimately from libunicode. It is relicensed under the + * dual LGPL/MPL with permission of the original authors. + * + * Copyright © 1999 Tom Tromey + * Copyright © 2005 Red Hat, Inc + * + * This library is free software; you can redistribute it and/or + * modify it either under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation + * (the "LGPL") or, at your option, under the terms of the Mozilla + * Public License Version 1.1 (the "MPL"). If you do not alter this + * notice, a recipient may use your version of this file under either + * the MPL or the LGPL. + * + * You should have received a copy of the LGPL along with this library + * in the file COPYING-LGPL-2.1; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * You should have received a copy of the MPL along with this library + * in the file COPYING-MPL-1.1 + * + * The contents of this file are subject to the Mozilla Public License + * Version 1.1 (the "License"); you may not use this file except in + * compliance with the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY + * OF ANY KIND, either express or implied. See the LGPL or the MPL for + * the specific language governing rights and limitations. + * + * The Original Code is cairo_unicode.c as distributed with the + * cairo graphics library. + * + * The Initial Developer of the Original Code is Tom Tromey. + * and Red Hat, Inc. + * + * Contributor(s): + * Owen Taylor <otaylor@redhat.com> + */ + +#include <limits.h> + +#include <cairoint.h> + +#define UTF8_COMPUTE(Char, Mask, Len) \ + if (Char < 128) \ + { \ + Len = 1; \ + Mask = 0x7f; \ + } \ + else if ((Char & 0xe0) == 0xc0) \ + { \ + Len = 2; \ + Mask = 0x1f; \ + } \ + else if ((Char & 0xf0) == 0xe0) \ + { \ + Len = 3; \ + Mask = 0x0f; \ + } \ + else if ((Char & 0xf8) == 0xf0) \ + { \ + Len = 4; \ + Mask = 0x07; \ + } \ + else if ((Char & 0xfc) == 0xf8) \ + { \ + Len = 5; \ + Mask = 0x03; \ + } \ + else if ((Char & 0xfe) == 0xfc) \ + { \ + Len = 6; \ + Mask = 0x01; \ + } \ + else \ + Len = -1; + +#define UTF8_LENGTH(Char) \ + ((Char) < 0x80 ? 1 : \ + ((Char) < 0x800 ? 2 : \ + ((Char) < 0x10000 ? 3 : \ + ((Char) < 0x200000 ? 4 : \ + ((Char) < 0x4000000 ? 5 : 6))))) + + +#define UTF8_GET(Result, Chars, Count, Mask, Len) \ + (Result) = (Chars)[0] & (Mask); \ + for ((Count) = 1; (Count) < (Len); ++(Count)) \ + { \ + if (((Chars)[(Count)] & 0xc0) != 0x80) \ + { \ + (Result) = -1; \ + break; \ + } \ + (Result) <<= 6; \ + (Result) |= ((Chars)[(Count)] & 0x3f); \ + } + +#define UNICODE_VALID(Char) \ + ((Char) < 0x110000 && \ + (((Char) & 0xFFFFF800) != 0xD800) && \ + ((Char) < 0xFDD0 || (Char) > 0xFDEF) && \ + ((Char) & 0xFFFE) != 0xFFFE) + + +static const char utf8_skip_data[256] = { + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, + 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1 +}; + +#define UTF8_NEXT_CHAR(p) (char *)((p) + utf8_skip_data[*(unsigned char *)(p)]) + +/* Converts a sequence of bytes encoded as UTF-8 to a Unicode character. + * If @p does not point to a valid UTF-8 encoded character, results are + * undefined. + **/ +static uint32_t +_utf8_get_char (const char *p) +{ + int i, mask = 0, len; + uint32_t result; + unsigned char c = (unsigned char) *p; + + UTF8_COMPUTE (c, mask, len); + if (len == -1) + return (uint32_t)-1; + UTF8_GET (result, p, i, mask, len); + + return result; +} + +/* Like _utf8_get_char, but take a maximum length + * and return (uint32_t)-2 on incomplete trailing character + */ +static uint32_t +_utf8_get_char_extended (const char *p, + long max_len) +{ + int i, len; + uint32_t wc = (unsigned char) *p; + + if (wc < 0x80) { + return wc; + } else if (wc < 0xc0) { + return (uint32_t)-1; + } else if (wc < 0xe0) { + len = 2; + wc &= 0x1f; + } else if (wc < 0xf0) { + len = 3; + wc &= 0x0f; + } else if (wc < 0xf8) { + len = 4; + wc &= 0x07; + } else if (wc < 0xfc) { + len = 5; + wc &= 0x03; + } else if (wc < 0xfe) { + len = 6; + wc &= 0x01; + } else { + return (uint32_t)-1; + } + + if (max_len >= 0 && len > max_len) { + for (i = 1; i < max_len; i++) { + if ((((unsigned char *)p)[i] & 0xc0) != 0x80) + return (uint32_t)-1; + } + return (uint32_t)-2; + } + + for (i = 1; i < len; ++i) { + uint32_t ch = ((unsigned char *)p)[i]; + + if ((ch & 0xc0) != 0x80) { + if (ch) + return (uint32_t)-1; + else + return (uint32_t)-2; + } + + wc <<= 6; + wc |= (ch & 0x3f); + } + + if (UTF8_LENGTH(wc) != len) + return (uint32_t)-1; + + return wc; +} + +/** + * _cairo_utf8_to_utf32: + * @str: an UTF-8 string + * @len: length of @str in bytes, or -1 if it is nul-terminated. + * If @len is supplied and the string has an embedded nul + * byte, only the portion before the nul byte is converted. + * @result: location to store a pointer to a newly allocated UTF-32 + * string (always native endian). Free with free(). A 0 + * word will be written after the last character. + * @items_written: location to store number of 32-bit words + * written. (Not including the trailing 0) + * + * Converts a UTF-8 string to UCS-4. UCS-4 is an encoding of Unicode + * with 1 32-bit word per character. The string is validated to + * consist entirely of valid Unicode characters. + * + * Return value: %CAIRO_STATUS_SUCCESS if the entire string was + * succesfully converted. %CAIRO_STATUS_INVALID_STRING if an + * an invalid sequence was found. + **/ +cairo_status_t +_cairo_utf8_to_ucs4 (const char *str, + int len, + uint32_t **result, + int *items_written) +{ + uint32_t *str32 = NULL; + int n_chars, i; + const char *in; + + in = str; + n_chars = 0; + while ((len < 0 || str + len - in > 0) && *in) + { + uint32_t wc = _utf8_get_char_extended (in, str + len - in); + if (wc & 0x80000000 || !UNICODE_VALID (wc)) + return CAIRO_STATUS_INVALID_STRING; + + n_chars++; + if (n_chars == INT_MAX) + return CAIRO_STATUS_INVALID_STRING; + + in = UTF8_NEXT_CHAR (in); + } + + str32 = malloc (sizeof (uint32_t) * (n_chars + 1)); + if (!str32) + return CAIRO_STATUS_NO_MEMORY; + + in = str; + for (i=0; i < n_chars; i++) { + str32[i] = _utf8_get_char (in); + in = UTF8_NEXT_CHAR (in); + } + str32[i] = 0; + + *result = str32; + if (items_written) + *items_written = n_chars; + + return CAIRO_STATUS_SUCCESS; +} + +/** + * _cairo_utf8_to_utf16: + * @str: an UTF-8 string + * @len: length of @str in bytes, or -1 if it is nul-terminated. + * If @len is supplied and the string has an embedded nul + * byte, only the portion before the nul byte is converted. + * @result: location to store a pointer to a newly allocated UTF-16 + * string (always native endian). Free with free(). A 0 + * word will be written after the last character. + * @items_written: location to store number of 16-bit words + * written. (Not including the trailing 0) + * + * Converts a UTF-8 string to UTF-16. UTF-16 is an encoding of Unicode + * where characters are represented either as a single 16-bit word, or + * as a pair of 16-bit "surrogates". The string is validated to + * consist entirely of valid Unicode characters. + * + * Return value: %CAIRO_STATUS_SUCCESS if the entire string was + * succesfully converted. %CAIRO_STATUS_INVALID_STRING if an + * an invalid sequence was found. + **/ +cairo_status_t +_cairo_utf8_to_utf16 (const char *str, + int len, + uint16_t **result, + int *items_written) +{ + uint16_t *str16 = NULL; + int n16, i; + const char *in; + + in = str; + n16 = 0; + while ((len < 0 || str + len - in > 0) && *in) { + uint32_t wc = _utf8_get_char_extended (in, str + len - in); + if (wc & 0x80000000 || !UNICODE_VALID (wc)) + return CAIRO_STATUS_INVALID_STRING; + + if (wc < 0x10000) + n16 += 1; + else + n16 += 2; + + if (n16 == INT_MAX - 1 || n16 == INT_MAX) + return CAIRO_STATUS_INVALID_STRING; + + in = UTF8_NEXT_CHAR (in); + } + + + str16 = malloc (sizeof (uint16_t) * (n16 + 1)); + if (!str16) + return CAIRO_STATUS_NO_MEMORY; + + in = str; + for (i = 0; i < n16;) { + uint32_t wc = _utf8_get_char (in); + + if (wc < 0x10000) { + str16[i++] = wc; + } else { + str16[i++] = (wc - 0x10000) / 0x400 + 0xd800; + str16[i++] = (wc - 0x10000) % 0x400 + 0xdc00; + } + + in = UTF8_NEXT_CHAR (in); + } + + str16[i] = 0; + + *result = str16; + if (items_written) + *items_written = n16; + + return CAIRO_STATUS_SUCCESS; +} |