| /* |
| * Copyright (C) 2007 Apple Inc. All rights reserved. |
| * Copyright (C) 2010 Patrick Gansterer <paroga@paroga.com> |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "third_party/blink/renderer/platform/wtf/text/utf8.h" |
| |
| #include "third_party/blink/renderer/platform/wtf/text/ascii_ctype.h" |
| #include "third_party/blink/renderer/platform/wtf/text/character_names.h" |
| #include "third_party/blink/renderer/platform/wtf/text/string_hasher.h" |
| |
| namespace WTF { |
| namespace unicode { |
| |
| inline int InlineUTF8SequenceLengthNonASCII(char b0) { |
| if ((b0 & 0xC0) != 0xC0) |
| return 0; |
| if ((b0 & 0xE0) == 0xC0) |
| return 2; |
| if ((b0 & 0xF0) == 0xE0) |
| return 3; |
| if ((b0 & 0xF8) == 0xF0) |
| return 4; |
| return 0; |
| } |
| |
| inline int InlineUTF8SequenceLength(char b0) { |
| return IsASCII(b0) ? 1 : InlineUTF8SequenceLengthNonASCII(b0); |
| } |
| |
| // Once the bits are split out into bytes of UTF-8, this is a mask OR-ed |
| // into the first byte, depending on how many bytes follow. There are |
| // as many entries in this table as there are UTF-8 sequence types. |
| // (I.e., one byte sequence, two byte... etc.). Remember that sequences |
| // for *legal* UTF-8 will be 4 or fewer bytes total. |
| static const unsigned char kFirstByteMark[7] = {0x00, 0x00, 0xC0, 0xE0, |
| 0xF0, 0xF8, 0xFC}; |
| |
| ConversionResult ConvertLatin1ToUTF8(const LChar** source_start, |
| const LChar* source_end, |
| char** target_start, |
| char* target_end) { |
| ConversionResult result = kConversionOK; |
| const LChar* source = *source_start; |
| char* target = *target_start; |
| while (source < source_end) { |
| UChar32 ch; |
| uint8_t bytes_to_write = 0; |
| const UChar32 kByteMask = 0xBF; |
| const UChar32 kByteMark = 0x80; |
| const LChar* old_source = |
| source; // In case we have to back up because of target overflow. |
| ch = static_cast<UChar32>(*source++); |
| |
| // Figure out how many bytes the result will require |
| if (ch < (UChar32)0x80) |
| bytes_to_write = 1; |
| else |
| bytes_to_write = 2; |
| |
| target += bytes_to_write; |
| if (target > target_end) { |
| source = old_source; // Back up source pointer! |
| target -= bytes_to_write; |
| result = kTargetExhausted; |
| break; |
| } |
| switch (bytes_to_write) { |
| case 2: |
| *--target = (char)((ch | kByteMark) & kByteMask); |
| ch >>= 6; |
| FALLTHROUGH; |
| case 1: |
| *--target = (char)(ch | kFirstByteMark[bytes_to_write]); |
| } |
| target += bytes_to_write; |
| } |
| *source_start = source; |
| *target_start = target; |
| return result; |
| } |
| |
| ConversionResult ConvertUTF16ToUTF8(const UChar** source_start, |
| const UChar* source_end, |
| char** target_start, |
| char* target_end, |
| bool strict) { |
| ConversionResult result = kConversionOK; |
| const UChar* source = *source_start; |
| char* target = *target_start; |
| while (source < source_end) { |
| UChar32 ch; |
| uint8_t bytes_to_write = 0; |
| const UChar32 kByteMask = 0xBF; |
| const UChar32 kByteMark = 0x80; |
| const UChar* old_source = |
| source; // In case we have to back up because of target overflow. |
| ch = static_cast<UChar32>(*source++); |
| // If we have a surrogate pair, convert to UChar32 first. |
| if (ch >= 0xD800 && ch <= 0xDBFF) { |
| // If the 16 bits following the high surrogate are in the source buffer... |
| if (source < source_end) { |
| UChar32 ch2 = static_cast<UChar32>(*source); |
| // If it's a low surrogate, convert to UChar32. |
| if (ch2 >= 0xDC00 && ch2 <= 0xDFFF) { |
| ch = ((ch - 0xD800) << 10) + (ch2 - 0xDC00) + 0x0010000; |
| ++source; |
| } else if (strict) { // it's an unpaired high surrogate |
| --source; // return to the illegal value itself |
| result = kSourceIllegal; |
| break; |
| } |
| } else { // We don't have the 16 bits following the high surrogate. |
| --source; // return to the high surrogate |
| result = kSourceExhausted; |
| break; |
| } |
| } else if (strict) { |
| // UTF-16 surrogate values are illegal in UTF-32 |
| if (ch >= 0xDC00 && ch <= 0xDFFF) { |
| --source; // return to the illegal value itself |
| result = kSourceIllegal; |
| break; |
| } |
| } |
| // Figure out how many bytes the result will require |
| if (ch < (UChar32)0x80) { |
| bytes_to_write = 1; |
| } else if (ch < (UChar32)0x800) { |
| bytes_to_write = 2; |
| } else if (ch < (UChar32)0x10000) { |
| bytes_to_write = 3; |
| } else if (ch < (UChar32)0x110000) { |
| bytes_to_write = 4; |
| } else { |
| bytes_to_write = 3; |
| ch = kReplacementCharacter; |
| } |
| |
| target += bytes_to_write; |
| if (target > target_end) { |
| source = old_source; // Back up source pointer! |
| target -= bytes_to_write; |
| result = kTargetExhausted; |
| break; |
| } |
| switch (bytes_to_write) { |
| case 4: |
| *--target = (char)((ch | kByteMark) & kByteMask); |
| ch >>= 6; |
| FALLTHROUGH; |
| case 3: |
| *--target = (char)((ch | kByteMark) & kByteMask); |
| ch >>= 6; |
| FALLTHROUGH; |
| case 2: |
| *--target = (char)((ch | kByteMark) & kByteMask); |
| ch >>= 6; |
| FALLTHROUGH; |
| case 1: |
| *--target = (char)(ch | kFirstByteMark[bytes_to_write]); |
| } |
| target += bytes_to_write; |
| } |
| *source_start = source; |
| *target_start = target; |
| return result; |
| } |
| |
| // This must be called with the length pre-determined by the first byte. |
| // If presented with a length > 4, this returns false. The Unicode |
| // definition of UTF-8 goes up to 4-byte sequences. |
| static bool IsLegalUTF8(const unsigned char* source, int length) { |
| unsigned char a; |
| const unsigned char* srcptr = source + length; |
| switch (length) { |
| default: |
| return false; |
| case 4: |
| if ((a = (*--srcptr)) < 0x80 || a > 0xBF) |
| return false; |
| FALLTHROUGH; |
| case 3: |
| if ((a = (*--srcptr)) < 0x80 || a > 0xBF) |
| return false; |
| FALLTHROUGH; |
| case 2: |
| if ((a = (*--srcptr)) > 0xBF) |
| return false; |
| |
| // no fall-through in this inner switch |
| switch (*source) { |
| case 0xE0: |
| if (a < 0xA0) |
| return false; |
| break; |
| case 0xED: |
| if (a > 0x9F) |
| return false; |
| break; |
| case 0xF0: |
| if (a < 0x90) |
| return false; |
| break; |
| case 0xF4: |
| if (a > 0x8F) |
| return false; |
| break; |
| default: |
| if (a < 0x80) |
| return false; |
| } |
| FALLTHROUGH; |
| |
| case 1: |
| if (*source >= 0x80 && *source < 0xC2) |
| return false; |
| } |
| if (*source > 0xF4) |
| return false; |
| return true; |
| } |
| |
| // Magic values subtracted from a buffer value during UTF8 conversion. |
| // This table contains as many values as there might be trailing bytes |
| // in a UTF-8 sequence. |
| static const UChar32 kOffsetsFromUTF8[6] = {0x00000000UL, |
| 0x00003080UL, |
| 0x000E2080UL, |
| 0x03C82080UL, |
| static_cast<UChar32>(0xFA082080UL), |
| static_cast<UChar32>(0x82082080UL)}; |
| |
| static inline UChar32 ReadUTF8Sequence(const char*& sequence, unsigned length) { |
| UChar32 character = 0; |
| |
| switch (length) { |
| case 6: |
| character += static_cast<unsigned char>(*sequence++); |
| character <<= 6; |
| FALLTHROUGH; |
| case 5: |
| character += static_cast<unsigned char>(*sequence++); |
| character <<= 6; |
| FALLTHROUGH; |
| case 4: |
| character += static_cast<unsigned char>(*sequence++); |
| character <<= 6; |
| FALLTHROUGH; |
| case 3: |
| character += static_cast<unsigned char>(*sequence++); |
| character <<= 6; |
| FALLTHROUGH; |
| case 2: |
| character += static_cast<unsigned char>(*sequence++); |
| character <<= 6; |
| FALLTHROUGH; |
| case 1: |
| character += static_cast<unsigned char>(*sequence++); |
| } |
| |
| return character - kOffsetsFromUTF8[length - 1]; |
| } |
| |
| ConversionResult ConvertUTF8ToUTF16(const char** source_start, |
| const char* source_end, |
| UChar** target_start, |
| UChar* target_end, |
| bool* source_all_ascii, |
| bool strict) { |
| ConversionResult result = kConversionOK; |
| const char* source = *source_start; |
| UChar* target = *target_start; |
| UChar or_all_data = 0; |
| while (source < source_end) { |
| int utf8_sequence_length = InlineUTF8SequenceLength(*source); |
| if (source_end - source < utf8_sequence_length) { |
| result = kSourceExhausted; |
| break; |
| } |
| // Do this check whether lenient or strict |
| if (!IsLegalUTF8(reinterpret_cast<const unsigned char*>(source), |
| utf8_sequence_length)) { |
| result = kSourceIllegal; |
| break; |
| } |
| |
| UChar32 character = ReadUTF8Sequence(source, utf8_sequence_length); |
| |
| if (target >= target_end) { |
| source -= utf8_sequence_length; // Back up source pointer! |
| result = kTargetExhausted; |
| break; |
| } |
| |
| if (U_IS_BMP(character)) { |
| // UTF-16 surrogate values are illegal in UTF-32 |
| if (U_IS_SURROGATE(character)) { |
| if (strict) { |
| source -= utf8_sequence_length; // return to the illegal value itself |
| result = kSourceIllegal; |
| break; |
| } |
| *target++ = kReplacementCharacter; |
| or_all_data |= kReplacementCharacter; |
| } else { |
| *target++ = static_cast<UChar>(character); // normal case |
| or_all_data |= character; |
| } |
| } else if (U_IS_SUPPLEMENTARY(character)) { |
| // target is a character in range 0xFFFF - 0x10FFFF |
| if (target + 1 >= target_end) { |
| source -= utf8_sequence_length; // Back up source pointer! |
| result = kTargetExhausted; |
| break; |
| } |
| *target++ = U16_LEAD(character); |
| *target++ = U16_TRAIL(character); |
| or_all_data = 0xffff; |
| } else { |
| if (strict) { |
| source -= utf8_sequence_length; // return to the start |
| result = kSourceIllegal; |
| break; // Bail out; shouldn't continue |
| } else { |
| *target++ = kReplacementCharacter; |
| or_all_data |= kReplacementCharacter; |
| } |
| } |
| } |
| *source_start = source; |
| *target_start = target; |
| |
| if (source_all_ascii) |
| *source_all_ascii = !(or_all_data & ~0x7f); |
| |
| return result; |
| } |
| |
| unsigned CalculateStringHashAndLengthFromUTF8MaskingTop8Bits( |
| const char* data, |
| const char* data_end, |
| unsigned& data_length, |
| unsigned& utf16_length) { |
| if (!data) |
| return 0; |
| |
| StringHasher string_hasher; |
| data_length = 0; |
| utf16_length = 0; |
| |
| while (data < data_end || (!data_end && *data)) { |
| if (IsASCII(*data)) { |
| string_hasher.AddCharacter(*data++); |
| data_length++; |
| utf16_length++; |
| continue; |
| } |
| |
| int utf8_sequence_length = InlineUTF8SequenceLengthNonASCII(*data); |
| data_length += utf8_sequence_length; |
| |
| if (!data_end) { |
| for (int i = 1; i < utf8_sequence_length; ++i) { |
| if (!data[i]) |
| return 0; |
| } |
| } else if (data_end - data < utf8_sequence_length) { |
| return 0; |
| } |
| |
| if (!IsLegalUTF8(reinterpret_cast<const unsigned char*>(data), |
| utf8_sequence_length)) |
| return 0; |
| |
| UChar32 character = ReadUTF8Sequence(data, utf8_sequence_length); |
| DCHECK(!IsASCII(character)); |
| |
| if (U_IS_BMP(character)) { |
| // UTF-16 surrogate values are illegal in UTF-32 |
| if (U_IS_SURROGATE(character)) |
| return 0; |
| string_hasher.AddCharacter(static_cast<UChar>(character)); // normal case |
| utf16_length++; |
| } else if (U_IS_SUPPLEMENTARY(character)) { |
| string_hasher.AddCharacters(static_cast<UChar>(U16_LEAD(character)), |
| static_cast<UChar>(U16_TRAIL(character))); |
| utf16_length += 2; |
| } else { |
| return 0; |
| } |
| } |
| |
| return string_hasher.HashWithTop8BitsMasked(); |
| } |
| |
| template <typename CharType> |
| ALWAYS_INLINE bool EqualWithUTF8Internal(const CharType* a, |
| const CharType* a_end, |
| const char* b, |
| const char* b_end) { |
| while (b < b_end) { |
| if (IsASCII(*b)) { |
| if (*a++ != *b++) |
| return false; |
| continue; |
| } |
| |
| int utf8_sequence_length = InlineUTF8SequenceLengthNonASCII(*b); |
| |
| if (b_end - b < utf8_sequence_length) |
| return false; |
| |
| if (!IsLegalUTF8(reinterpret_cast<const unsigned char*>(b), |
| utf8_sequence_length)) |
| return 0; |
| |
| UChar32 character = ReadUTF8Sequence(b, utf8_sequence_length); |
| DCHECK(!IsASCII(character)); |
| |
| if (U_IS_BMP(character)) { |
| // UTF-16 surrogate values are illegal in UTF-32 |
| if (U_IS_SURROGATE(character)) |
| return false; |
| if (*a++ != character) |
| return false; |
| } else if (U_IS_SUPPLEMENTARY(character)) { |
| if (*a++ != U16_LEAD(character)) |
| return false; |
| if (*a++ != U16_TRAIL(character)) |
| return false; |
| } else { |
| return false; |
| } |
| } |
| |
| return a == a_end; |
| } |
| |
| bool EqualUTF16WithUTF8(const UChar* a, |
| const UChar* a_end, |
| const char* b, |
| const char* b_end) { |
| return EqualWithUTF8Internal(a, a_end, b, b_end); |
| } |
| |
| bool EqualLatin1WithUTF8(const LChar* a, |
| const LChar* a_end, |
| const char* b, |
| const char* b_end) { |
| return EqualWithUTF8Internal(a, a_end, b, b_end); |
| } |
| |
| } // namespace unicode |
| } // namespace WTF |
