v8/src/unicode-inl.h
2013-03-13 19:43:45 +00:00

218 lines
6.7 KiB
C++

// Copyright 2007-2010 the V8 project authors. All rights reserved.
// 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.
#ifndef V8_UNICODE_INL_H_
#define V8_UNICODE_INL_H_
#include "unicode.h"
#include "checks.h"
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;
}
}
uint16_t Latin1::ConvertNonLatin1ToLatin1(uint16_t c) {
ASSERT(c > Latin1::kMaxChar);
switch (c) {
// 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.
case 0x178:
return 0xff;
}
return 0;
}
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;
}
unsigned Utf8::Encode(char* str, uchar c, int previous) {
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) {
if (Utf16::IsTrailSurrogate(c) &&
Utf16::IsLeadSurrogate(previous)) {
const int kUnmatchedSize = kSizeOfUnmatchedSurrogate;
return Encode(str - kUnmatchedSize,
Utf16::CombineSurrogatePair(previous, c),
Utf16::kNoPreviousCharacter) - kUnmatchedSize;
}
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);
}
unsigned Utf8::Length(uchar c, int previous) {
if (c <= kMaxOneByteChar) {
return 1;
} else if (c <= kMaxTwoByteChar) {
return 2;
} else if (c <= kMaxThreeByteChar) {
if (Utf16::IsTrailSurrogate(c) &&
Utf16::IsLeadSurrogate(previous)) {
return kSizeOfUnmatchedSurrogate - kBytesSavedByCombiningSurrogates;
}
return 3;
} else {
return 4;
}
}
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;
memcpy(data, buffer_, memcpy_length*sizeof(uint16_t));
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;
}
} // namespace unibrow
#endif // V8_UNICODE_INL_H_