Repo created

TMessagesProj/jni/voip/webrtc/base/i18n/char_iterator.cc

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+// 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