Nagram/TMessagesProj/jni/voip/webrtc/base/i18n/char_iterator.cc
2020-09-30 16:48:47 +03:00

153 lines
4.1 KiB
C++

// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/i18n/char_iterator.h"
#include "base/logging.h"
#include "third_party/icu/source/common/unicode/utf16.h"
#include "third_party/icu/source/common/unicode/utf8.h"
namespace base {
namespace i18n {
// UTF8CharIterator ------------------------------------------------------------
UTF8CharIterator::UTF8CharIterator(const std::string* str)
: str_(reinterpret_cast<const uint8_t*>(str->data())),
len_(str->size()),
array_pos_(0),
next_pos_(0),
char_pos_(0),
char_(0) {
if (len_)
U8_NEXT(str_, next_pos_, len_, char_);
}
UTF8CharIterator::~UTF8CharIterator() = default;
bool UTF8CharIterator::Advance() {
if (array_pos_ >= len_)
return false;
array_pos_ = next_pos_;
char_pos_++;
if (next_pos_ < len_)
U8_NEXT(str_, next_pos_, len_, char_);
return true;
}
// UTF16CharIterator -----------------------------------------------------------
UTF16CharIterator::UTF16CharIterator(const string16* str)
: UTF16CharIterator(str, 0) {}
UTF16CharIterator::UTF16CharIterator(const char16* str, size_t str_len)
: UTF16CharIterator(str, str_len, 0) {}
UTF16CharIterator::UTF16CharIterator(UTF16CharIterator&& to_move) = default;
UTF16CharIterator::~UTF16CharIterator() = default;
UTF16CharIterator& UTF16CharIterator::operator=(UTF16CharIterator&& to_move) =
default;
// static
UTF16CharIterator UTF16CharIterator::LowerBound(const string16* str,
size_t array_index) {
return LowerBound(reinterpret_cast<const char16*>(str->data()), str->length(),
array_index);
}
// static
UTF16CharIterator UTF16CharIterator::LowerBound(const char16* str,
size_t length,
size_t array_index) {
DCHECK_LE(array_index, length);
U16_SET_CP_START(str, 0, array_index);
return UTF16CharIterator(str, length, array_index);
}
// static
UTF16CharIterator UTF16CharIterator::UpperBound(const string16* str,
size_t array_index) {
return UpperBound(reinterpret_cast<const char16*>(str->data()), str->length(),
array_index);
}
// static
UTF16CharIterator UTF16CharIterator::UpperBound(const char16* str,
size_t length,
size_t array_index) {
DCHECK_LE(array_index, length);
U16_SET_CP_LIMIT(str, 0, array_index, length);
return UTF16CharIterator(str, length, array_index);
}
int32_t UTF16CharIterator::NextCodePoint() const {
if (next_pos_ >= len_)
return 0;
UChar32 c;
U16_GET(str_, 0, next_pos_, len_, c);
return c;
}
int32_t UTF16CharIterator::PreviousCodePoint() const {
if (array_pos_ <= 0)
return 0;
uint32_t pos = array_pos_;
UChar32 c;
U16_PREV(str_, 0, pos, c);
return c;
}
bool UTF16CharIterator::Advance() {
if (array_pos_ >= len_)
return false;
array_pos_ = next_pos_;
char_offset_++;
if (next_pos_ < len_)
ReadChar();
return true;
}
bool UTF16CharIterator::Rewind() {
if (array_pos_ <= 0)
return false;
next_pos_ = array_pos_;
char_offset_--;
U16_PREV(str_, 0, array_pos_, char_);
return true;
}
UTF16CharIterator::UTF16CharIterator(const string16* str, int32_t initial_pos)
: UTF16CharIterator(str->data(), str->length(), initial_pos) {}
UTF16CharIterator::UTF16CharIterator(const char16* str,
size_t str_len,
int32_t initial_pos)
: str_(str),
len_(str_len),
array_pos_(initial_pos),
next_pos_(initial_pos),
char_offset_(0),
char_(0) {
// This has the side-effect of advancing |next_pos_|.
if (array_pos_ < len_)
ReadChar();
}
void UTF16CharIterator::ReadChar() {
// This is actually a huge macro, so is worth having in a separate function.
U16_NEXT(str_, next_pos_, len_, char_);
}
} // namespace i18n
} // namespace base