X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=src%2Fvideo%2Ffont.cpp;h=c61ee431ec1df8c1e92f0324093c58d04c0c3251;hb=6f5f82abb84b33fd400c3b82a5e2be2a6cf8ce21;hp=42aa45583916fc7c2c4afef3a4c9e6a09fa6e241;hpb=cea96e02f596a749eaf96637dbec6976fe7f4d24;p=supertux.git diff --git a/src/video/font.cpp b/src/video/font.cpp index 42aa45583..c61ee431e 100644 --- a/src/video/font.cpp +++ b/src/video/font.cpp @@ -36,7 +36,7 @@ Font::Font(const std::string& file, const std::string& shadowfile, { chars = new Surface(file); shadow_chars = new Surface(shadowfile); - + first_char = 32; char_count = ((int) chars->get_height() / h) * 16; } @@ -145,9 +145,9 @@ Font::draw(const std::string& text, const Vector& pos_, FontAlignment alignment, if(l > sizeof(temp)-1) l = sizeof(temp)-1; - + temp[text.copy(temp, l - i, i)] = '\0'; - + // calculate X positions based on the alignment type Vector pos = Vector(pos_); if(alignment == CENTER_ALLIGN) @@ -163,7 +163,7 @@ Font::draw(const std::string& text, const Vector& pos_, FontAlignment alignment, } void -Font::draw_text(const std::string& text, const Vector& pos, +Font::draw_text(const std::string& text, const Vector& pos, DrawingEffect drawing_effect, float alpha) const { if(shadowsize > 0) @@ -173,49 +173,66 @@ Font::draw_text(const std::string& text, const Vector& pos, draw_chars(chars, text, pos, drawing_effect, alpha); } -/** decoding of a byte stream to a single unicode character. - * This should be correct for well formed utf-8 sequences but doesn't check for - * all forms of illegal sequences. - * (see unicode standard section 3.10 table 3-5 and 3-6 for details) +namespace { + +/** + * returns true if this byte matches a bitmask of 10xx.xxxx, i.e. it is the 2nd, 3rd or 4th byte of a multibyte utf8 string + */ +bool has_multibyte_mark(unsigned char c) { + return ((c & 0300) == 0200); +} + +/** + * gets unicode character at byte position @a p of UTF-8 encoded @a text, then advances @a p to the next character. + * @throws std::runtime_error if decoding fails. + * See unicode standard section 3.10 table 3-5 and 3-6 for details. */ uint32_t decode_utf8(const std::string& text, size_t& p) { - // 1 byte sequence - uint32_t c = (unsigned char) text[p++]; - if(c <= 0x7F) { - return c; + uint32_t c1 = (unsigned char) text[p+0]; + + if (has_multibyte_mark(c1)) std::runtime_error("Malformed utf-8 sequence"); + + if ((c1 & 0200) == 0000) { + // 0xxx.xxxx: 1 byte sequence + p+=1; + return c1; } - - // 2 byte sequence - if(p >= text.size()) - throw std::runtime_error("Malformed utf-8 sequence"); - uint32_t c2 = (unsigned char) text[p++]; - if(c <= 0xDF) { - if(c < 0xC2) - throw std::runtime_error("Malformed utf-8 sequence"); - return (c & 0x1F) << 6 | (c2 & 0x3F); + else if ((c1 & 0340) == 0300) { + // 110x.xxxx: 2 byte sequence + if(p+1 >= text.size()) throw std::range_error("Malformed utf-8 sequence"); + uint32_t c2 = (unsigned char) text[p+1]; + if (!has_multibyte_mark(c2)) throw std::runtime_error("Malformed utf-8 sequence"); + p+=2; + return (c1 & 0037) << 6 | (c2 & 0077); } - - // 3 byte sequence - if(p >= text.size()) - throw std::runtime_error("Malformed utf-8 sequence"); - uint32_t c3 = (unsigned char) text[p++]; - if(c <= 0xEF) { - return (c & 0x0F) << 12 | (c2 & 0x3F) << 6 | (c3 & 0x3F); + else if ((c1 & 0360) == 0340) { + // 1110.xxxx: 3 byte sequence + if(p+2 >= text.size()) throw std::range_error("Malformed utf-8 sequence"); + uint32_t c2 = (unsigned char) text[p+1]; + uint32_t c3 = (unsigned char) text[p+2]; + if (!has_multibyte_mark(c2)) throw std::runtime_error("Malformed utf-8 sequence"); + if (!has_multibyte_mark(c3)) throw std::runtime_error("Malformed utf-8 sequence"); + p+=3; + return (c1 & 0017) << 12 | (c2 & 0077) << 6 | (c3 & 0077); } - - // 4 byte sequence - if(p >= text.size()) - throw std::runtime_error("Malformed utf-8 sequence"); - uint32_t c4 = (unsigned char) text[p++]; - if(c <= 0xF4) { - return (c & 0x07) << 18 | (c2 & 0x3F) << 12 | (c3 & 0x3F) << 6 - | (c4 & 0x3F); + else if ((c1 & 0370) == 0360) { + // 1111.0xxx: 4 byte sequence + if(p+3 >= text.size()) throw std::range_error("Malformed utf-8 sequence"); + uint32_t c2 = (unsigned char) text[p+1]; + uint32_t c3 = (unsigned char) text[p+2]; + uint32_t c4 = (unsigned char) text[p+4]; + if (!has_multibyte_mark(c2)) throw std::runtime_error("Malformed utf-8 sequence"); + if (!has_multibyte_mark(c3)) throw std::runtime_error("Malformed utf-8 sequence"); + if (!has_multibyte_mark(c4)) throw std::runtime_error("Malformed utf-8 sequence"); + p+=4; + return (c1 & 0007) << 18 | (c2 & 0077) << 12 | (c3 & 0077) << 6 | (c4 & 0077); } - throw std::runtime_error("Malformed utf-8 sequence"); } +} + void Font::draw_chars(Surface* pchars, const std::string& text, const Vector& pos, DrawingEffect drawing_effect, float alpha) const @@ -223,11 +240,19 @@ Font::draw_chars(Surface* pchars, const std::string& text, const Vector& pos, Vector p = pos; size_t i = 0; while(i < text.size()) { - uint32_t c = decode_utf8(text, i); + uint32_t c; + try { + c = decode_utf8(text, i); + } + catch (std::runtime_error) { + log_debug << "Malformed utf-8 sequence beginning with " << *((uint32_t*)(text.c_str() + i)) << " found " << std::endl; + c = 0; + i++; + } ssize_t font_index; // a non-printable character? - if(c == '\n') { + if(c == '\n') { p.x = pos.x; p.y += h + 2; continue; @@ -246,11 +271,11 @@ Font::draw_chars(Surface* pchars, const std::string& text, const Vector& pos, font_index = 0; } } - + if(font_index < 0 || font_index >= (ssize_t) char_count) { log_debug << "Unsupported utf-8 character found" << std::endl; font_index = 0; - } + } int source_x = (font_index % 16) * w; int source_y = (font_index / 16) * h;