unicode-inl.h 7.24 KB
Newer Older
1
// Copyright 2007-2010 the V8 project authors. All rights reserved.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * 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.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "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 THE COPYRIGHT
// OWNER 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.

28 29
#ifndef V8_UNICODE_INL_H_
#define V8_UNICODE_INL_H_
30 31

#include "unicode.h"
32
#include "checks.h"
33
#include "platform.h"
34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82

namespace unibrow {

template <class T, int s> bool Predicate<T, s>::get(uchar code_point) {
  CacheEntry entry = entries_[code_point & kMask];
  if (entry.code_point_ == code_point) return entry.value_;
  return CalculateValue(code_point);
}

template <class T, int s> bool Predicate<T, s>::CalculateValue(
    uchar code_point) {
  bool result = T::Is(code_point);
  entries_[code_point & kMask] = CacheEntry(code_point, result);
  return result;
}

template <class T, int s> int Mapping<T, s>::get(uchar c, uchar n,
    uchar* result) {
  CacheEntry entry = entries_[c & kMask];
  if (entry.code_point_ == c) {
    if (entry.offset_ == 0) {
      return 0;
    } else {
      result[0] = c + entry.offset_;
      return 1;
    }
  } else {
    return CalculateValue(c, n, result);
  }
}

template <class T, int s> int Mapping<T, s>::CalculateValue(uchar c, uchar n,
    uchar* result) {
  bool allow_caching = true;
  int length = T::Convert(c, n, result, &allow_caching);
  if (allow_caching) {
    if (length == 1) {
      entries_[c & kMask] = CacheEntry(c, result[0] - c);
      return 1;
    } else {
      entries_[c & kMask] = CacheEntry(c, 0);
      return 0;
    }
  } else {
    return length;
  }
}


83
uint16_t Latin1::ConvertNonLatin1ToLatin1(uint16_t c) {
84 85
  ASSERT(c > Latin1::kMaxChar);
  switch (c) {
86 87 88 89 90 91
    // This are equivalent characters in unicode.
    case 0x39c:
    case 0x3bc:
      return 0xb5;
    // This is an uppercase of a Latin-1 character
    // outside of Latin-1.
92
    case 0x178:
93
      return 0xff;
94
  }
95
  return 0;
96 97 98
}


99 100 101 102 103 104 105 106 107 108 109
unsigned Utf8::EncodeOneByte(char* str, uint8_t c) {
  static const int kMask = ~(1 << 6);
  if (c <= kMaxOneByteChar) {
    str[0] = c;
    return 1;
  }
  str[0] = 0xC0 | (c >> 6);
  str[1] = 0x80 | (c & kMask);
  return 2;
}

110 111 112 113 114 115 116 117
// Encode encodes the UTF-16 code units c and previous into the given str
// buffer, and combines surrogate code units into single code points. If
// replace_invalid is set to true, orphan surrogate code units will be replaced
// with kBadChar.
unsigned Utf8::Encode(char* str,
                      uchar c,
                      int previous,
                      bool replace_invalid) {
118 119 120 121 122 123 124 125 126
  static const int kMask = ~(1 << 6);
  if (c <= kMaxOneByteChar) {
    str[0] = c;
    return 1;
  } else if (c <= kMaxTwoByteChar) {
    str[0] = 0xC0 | (c >> 6);
    str[1] = 0x80 | (c & kMask);
    return 2;
  } else if (c <= kMaxThreeByteChar) {
127
    if (Utf16::IsSurrogatePair(previous, c)) {
128 129 130
      const int kUnmatchedSize = kSizeOfUnmatchedSurrogate;
      return Encode(str - kUnmatchedSize,
                    Utf16::CombineSurrogatePair(previous, c),
131 132 133 134 135 136
                    Utf16::kNoPreviousCharacter,
                    replace_invalid) - kUnmatchedSize;
    } else if (replace_invalid &&
               (Utf16::IsLeadSurrogate(c) ||
               Utf16::IsTrailSurrogate(c))) {
      c = kBadChar;
137
    }
138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162
    str[0] = 0xE0 | (c >> 12);
    str[1] = 0x80 | ((c >> 6) & kMask);
    str[2] = 0x80 | (c & kMask);
    return 3;
  } else {
    str[0] = 0xF0 | (c >> 18);
    str[1] = 0x80 | ((c >> 12) & kMask);
    str[2] = 0x80 | ((c >> 6) & kMask);
    str[3] = 0x80 | (c & kMask);
    return 4;
  }
}


uchar Utf8::ValueOf(const byte* bytes, unsigned length, unsigned* cursor) {
  if (length <= 0) return kBadChar;
  byte first = bytes[0];
  // Characters between 0000 and 0007F are encoded as a single character
  if (first <= kMaxOneByteChar) {
    *cursor += 1;
    return first;
  }
  return CalculateValue(bytes, length, cursor);
}

163
unsigned Utf8::Length(uchar c, int previous) {
164 165 166 167 168
  if (c <= kMaxOneByteChar) {
    return 1;
  } else if (c <= kMaxTwoByteChar) {
    return 2;
  } else if (c <= kMaxThreeByteChar) {
169 170 171 172
    if (Utf16::IsTrailSurrogate(c) &&
        Utf16::IsLeadSurrogate(previous)) {
      return kSizeOfUnmatchedSurrogate - kBytesSavedByCombiningSurrogates;
    }
173 174 175 176 177 178
    return 3;
  } else {
    return 4;
  }
}

179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215
Utf8DecoderBase::Utf8DecoderBase()
  : unbuffered_start_(NULL),
    utf16_length_(0),
    last_byte_of_buffer_unused_(false) {}

Utf8DecoderBase::Utf8DecoderBase(uint16_t* buffer,
                                 unsigned buffer_length,
                                 const uint8_t* stream,
                                 unsigned stream_length) {
  Reset(buffer, buffer_length, stream, stream_length);
}

template<unsigned kBufferSize>
Utf8Decoder<kBufferSize>::Utf8Decoder(const char* stream, unsigned length)
  : Utf8DecoderBase(buffer_,
                    kBufferSize,
                    reinterpret_cast<const uint8_t*>(stream),
                    length) {
}

template<unsigned kBufferSize>
void Utf8Decoder<kBufferSize>::Reset(const char* stream, unsigned length) {
  Utf8DecoderBase::Reset(buffer_,
                         kBufferSize,
                         reinterpret_cast<const uint8_t*>(stream),
                         length);
}

template <unsigned kBufferSize>
unsigned Utf8Decoder<kBufferSize>::WriteUtf16(uint16_t* data,
                                              unsigned length) const {
  ASSERT(length > 0);
  if (length > utf16_length_) length = utf16_length_;
  // memcpy everything in buffer.
  unsigned buffer_length =
      last_byte_of_buffer_unused_ ? kBufferSize - 1 : kBufferSize;
  unsigned memcpy_length = length <= buffer_length  ? length : buffer_length;
216
  v8::internal::OS::MemCopy(data, buffer_, memcpy_length*sizeof(uint16_t));
217 218 219 220 221 222 223
  if (length <= buffer_length) return length;
  ASSERT(unbuffered_start_ != NULL);
  // Copy the rest the slow way.
  WriteUtf16Slow(unbuffered_start_,
                 data + buffer_length,
                 length - buffer_length);
  return length;
224 225 226 227
}

}  // namespace unibrow

228
#endif  // V8_UNICODE_INL_H_