diff options
Diffstat (limited to 'libqpdf/QUtil.cc')
-rw-r--r-- | libqpdf/QUtil.cc | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/libqpdf/QUtil.cc b/libqpdf/QUtil.cc index 7c2d9bc9..ba4aea2c 100644 --- a/libqpdf/QUtil.cc +++ b/libqpdf/QUtil.cc @@ -893,6 +893,67 @@ QUtil::parse_numrange(char const* range, int max) return result; } +enum encoding_e { e_utf16 }; + +static +std::string +transcode_utf8(std::string const& utf8_val, encoding_e encoding) +{ + std::string result = "\xfe\xff"; + size_t len = utf8_val.length(); + for (size_t i = 0; i < len; ++i) + { + unsigned char ch = static_cast<unsigned char>(utf8_val.at(i)); + if (ch < 128) + { + result += QUtil::toUTF16(ch); + } + else + { + size_t bytes_needed = 0; + unsigned bit_check = 0x40; + unsigned char to_clear = 0x80; + while (ch & bit_check) + { + ++bytes_needed; + to_clear |= bit_check; + bit_check >>= 1; + } + + if (((bytes_needed > 5) || (bytes_needed < 1)) || + ((i + bytes_needed) >= len)) + { + result += "\xff\xfd"; + } + else + { + unsigned long codepoint = (ch & ~to_clear); + while (bytes_needed > 0) + { + --bytes_needed; + ch = utf8_val.at(++i); + if ((ch & 0xc0) != 0x80) + { + --i; + codepoint = 0xfffd; + break; + } + codepoint <<= 6; + codepoint += (ch & 0x3f); + } + result += QUtil::toUTF16(codepoint); + } + } + } + return result; +} + +std::string +QUtil::utf8_to_utf16(std::string const& utf8) +{ + return transcode_utf8(utf8, e_utf16); +} + std::string QUtil::utf8_to_ascii(std::string const& utf8, char unknown_char) { |