Repo created

TMessagesProj/jni/voip/webrtc/base/i18n/break_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/break_iterator.h"
+
+#include <stdint.h>
+
+#include "base/logging.h"
+#include "third_party/icu/source/common/unicode/ubrk.h"
+#include "third_party/icu/source/common/unicode/uchar.h"
+#include "third_party/icu/source/common/unicode/ustring.h"
+
+namespace base {
+namespace i18n {
+
+const size_t npos = static_cast<size_t>(-1);
+
+BreakIterator::BreakIterator(const StringPiece16& str, BreakType break_type)
+    : iter_(nullptr),
+      string_(str),
+      break_type_(break_type),
+      prev_(npos),
+      pos_(0) {}
+
+BreakIterator::BreakIterator(const StringPiece16& str, const string16& rules)
+    : iter_(nullptr),
+      string_(str),
+      rules_(rules),
+      break_type_(RULE_BASED),
+      prev_(npos),
+      pos_(0) {}
+
+BreakIterator::~BreakIterator() {
+  if (iter_)
+    ubrk_close(static_cast<UBreakIterator*>(iter_));
+}
+
+bool BreakIterator::Init() {
+  UErrorCode status = U_ZERO_ERROR;
+  UParseError parse_error;
+  UBreakIteratorType break_type;
+  switch (break_type_) {
+    case BREAK_CHARACTER:
+      break_type = UBRK_CHARACTER;
+      break;
+    case BREAK_WORD:
+      break_type = UBRK_WORD;
+      break;
+    case BREAK_SENTENCE:
+      break_type = UBRK_SENTENCE;
+      break;
+    case BREAK_LINE:
+    case BREAK_NEWLINE:
+    case RULE_BASED: // (Keep compiler happy, break_type not used in this case)
+      break_type = UBRK_LINE;
+      break;
+    default:
+      NOTREACHED() << "invalid break_type_";
+      return false;
+  }
+  if (break_type_ == RULE_BASED) {
+    iter_ = ubrk_openRules(rules_.c_str(),
+                           static_cast<int32_t>(rules_.length()),
+                           string_.data(),
+                           static_cast<int32_t>(string_.size()),
+                           &parse_error,
+                           &status);
+    if (U_FAILURE(status)) {
+      NOTREACHED() << "ubrk_openRules failed to parse rule string at line "
+          << parse_error.line << ", offset " << parse_error.offset;
+    }
+  } else {
+    iter_ = ubrk_open(break_type, nullptr, string_.data(),
+                      static_cast<int32_t>(string_.size()), &status);
+    if (U_FAILURE(status)) {
+      NOTREACHED() << "ubrk_open failed for type " << break_type
+          << " with error " << status;
+    }
+  }
+
+  if (U_FAILURE(status)) {
+    return false;
+  }
+
+  // Move the iterator to the beginning of the string.
+  ubrk_first(static_cast<UBreakIterator*>(iter_));
+  return true;
+}
+
+bool BreakIterator::Advance() {
+  int32_t pos;
+  int32_t status;
+  prev_ = pos_;
+  switch (break_type_) {
+    case BREAK_CHARACTER:
+    case BREAK_WORD:
+    case BREAK_LINE:
+    case BREAK_SENTENCE:
+    case RULE_BASED:
+      pos = ubrk_next(static_cast<UBreakIterator*>(iter_));
+      if (pos == UBRK_DONE) {
+        pos_ = npos;
+        return false;
+      }
+      pos_ = static_cast<size_t>(pos);
+      return true;
+    case BREAK_NEWLINE:
+      do {
+        pos = ubrk_next(static_cast<UBreakIterator*>(iter_));
+        if (pos == UBRK_DONE)
+          break;
+        pos_ = static_cast<size_t>(pos);
+        status = ubrk_getRuleStatus(static_cast<UBreakIterator*>(iter_));
+      } while (status >= UBRK_LINE_SOFT && status < UBRK_LINE_SOFT_LIMIT);
+      if (pos == UBRK_DONE && prev_ == pos_) {
+        pos_ = npos;
+        return false;
+      }
+      return true;
+    default:
+      NOTREACHED() << "invalid break_type_";
+      return false;
+  }
+}
+
+bool BreakIterator::SetText(const base::char16* text, const size_t length) {
+  UErrorCode status = U_ZERO_ERROR;
+  ubrk_setText(static_cast<UBreakIterator*>(iter_),
+               text, length, &status);
+  pos_ = 0;  // implicit when ubrk_setText is done
+  prev_ = npos;
+  if (U_FAILURE(status)) {
+    NOTREACHED() << "ubrk_setText failed";
+    return false;
+  }
+  string_ = StringPiece16(text, length);
+  return true;
+}
+
+bool BreakIterator::IsWord() const {
+  return GetWordBreakStatus() == IS_WORD_BREAK;
+}
+
+BreakIterator::WordBreakStatus BreakIterator::GetWordBreakStatus() const {
+  int32_t status = ubrk_getRuleStatus(static_cast<UBreakIterator*>(iter_));
+  if (break_type_ != BREAK_WORD && break_type_ != RULE_BASED)
+    return IS_LINE_OR_CHAR_BREAK;
+  // In ICU 60, trying to advance past the end of the text does not change
+  // |status| so that |pos_| has to be checked as well as |status|.
+  // See http://bugs.icu-project.org/trac/ticket/13447 .
+  return (status == UBRK_WORD_NONE || pos_ == npos) ? IS_SKIPPABLE_WORD
+                                                    : IS_WORD_BREAK;
+}
+
+bool BreakIterator::IsEndOfWord(size_t position) const {
+  if (break_type_ != BREAK_WORD && break_type_ != RULE_BASED)
+    return false;
+
+  UBreakIterator* iter = static_cast<UBreakIterator*>(iter_);
+  UBool boundary = ubrk_isBoundary(iter, static_cast<int32_t>(position));
+  int32_t status = ubrk_getRuleStatus(iter);
+  return (!!boundary && status != UBRK_WORD_NONE);
+}
+
+bool BreakIterator::IsStartOfWord(size_t position) const {
+  if (break_type_ != BREAK_WORD && break_type_ != RULE_BASED)
+    return false;
+
+  UBreakIterator* iter = static_cast<UBreakIterator*>(iter_);
+  UBool boundary = ubrk_isBoundary(iter, static_cast<int32_t>(position));
+  ubrk_next(iter);
+  int32_t next_status = ubrk_getRuleStatus(iter);
+  return (!!boundary && next_status != UBRK_WORD_NONE);
+}
+
+bool BreakIterator::IsSentenceBoundary(size_t position) const {
+  if (break_type_ != BREAK_SENTENCE && break_type_ != RULE_BASED)
+    return false;
+
+  UBreakIterator* iter = static_cast<UBreakIterator*>(iter_);
+  return !!ubrk_isBoundary(iter, static_cast<int32_t>(position));
+}
+
+bool BreakIterator::IsGraphemeBoundary(size_t position) const {
+  if (break_type_ != BREAK_CHARACTER)
+    return false;
+
+  UBreakIterator* iter = static_cast<UBreakIterator*>(iter_);
+  return !!ubrk_isBoundary(iter, static_cast<int32_t>(position));
+}
+
+string16 BreakIterator::GetString() const {
+  return GetStringPiece().as_string();
+}
+
+StringPiece16 BreakIterator::GetStringPiece() const {
+  DCHECK(prev_ != npos && pos_ != npos);
+  return string_.substr(prev_, pos_ - prev_);
+}
+
+}  // namespace i18n
+}  // namespace base