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// Copyright 2007-2010 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_UNICODE_INL_H_
#define V8_UNICODE_INL_H_
#include "src/unicode.h"
#include "src/base/logging.h"
#include "src/utils.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;
}
}
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;
}
// 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) {
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) {
DCHECK(!Utf16::IsLeadSurrogate(Utf16::kNoPreviousCharacter));
if (Utf16::IsSurrogatePair(previous, c)) {
const int kUnmatchedSize = kSizeOfUnmatchedSurrogate;
return Encode(str - kUnmatchedSize,
Utf16::CombineSurrogatePair(previous, c),
Utf16::kNoPreviousCharacter,
replace_invalid) - kUnmatchedSize;
} else if (replace_invalid &&
(Utf16::IsLeadSurrogate(c) ||
Utf16::IsTrailSurrogate(c))) {
c = kBadChar;
}
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, size_t length, size_t* cursor) {
if (length <= 0) return kBadChar;
byte first = bytes[0];
// Characters between 0000 and 007F are encoded as a single character
if (V8_LIKELY(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) {
DCHECK(!Utf16::IsLeadSurrogate(Utf16::kNoPreviousCharacter));
if (Utf16::IsSurrogatePair(previous, c)) {
return kSizeOfUnmatchedSurrogate - kBytesSavedByCombiningSurrogates;
}
return 3;
} else {
return 4;
}
}
bool Utf8::IsValidCharacter(uchar c) {
return c < 0xD800u || (c >= 0xE000u && c < 0xFDD0u) ||
(c > 0xFDEFu && c <= 0x10FFFFu && (c & 0xFFFEu) != 0xFFFEu &&
c != kBadChar);
}
} // namespace unibrow
#endif // V8_UNICODE_INL_H_
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