Remove hyphenation code from Chromium.

content/renderer/hyphenator/hyphenator.cc

-// Copyright (c) 2012 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 "content/renderer/hyphenator/hyphenator.h"
-
-#include "base/files/memory_mapped_file.h"
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/strings/string_util.h"
-#include "base/strings/utf_string_conversions.h"
-#include "content/common/hyphenator_messages.h"
-#include "content/public/renderer/render_thread.h"
-#include "third_party/hyphen/hyphen.h"
-#include "third_party/icu/source/common/unicode/uscript.h"
-
-namespace {
-
-// A class that converts a sequence of UTF-8 characters to UTF-16 ones and holds
-// only the length of converted UTF-16 characters. This class is used for
-// creating a mapping from the position of a UTF-8 string to a position of a
-// UTF-16 string without unnecessary conversions. Even though the following
-// snippet produces the same mapping, it needs to convert same characters many
-// times. This class incrementally counts the number of converted UTF-16
-// characters to avoid this problem.
-//
-//   scoped_ptr<size_t[]> position(new size_t[text.length()]);
-//   for (size_t i = 0; i < text.length(); ++i)
-//     position[i] = UTF8ToUTF16(text.substr(0, i)).length();
-//
-class UTF16TextLength {
- public:
-  UTF16TextLength();
-  ~UTF16TextLength();
-
-  // Returns the current position.
-  int utf16_length() const { return utf16_length_; }
-
-  // Appends one UTF-8 character to this converter and advances the converted
-  // position. This converter increases the position by one when it finishes
-  // reading a BMP character and increases by two when it finish reading a
-  // non-BMP character.
-  void Append(char c);
-
- private:
-  // The length of the converted UTF-16 text.
-  int utf16_length_;
-
-  // The buffer that stores UTF-8 characters being converted.
-  std::string utf8_text_;
-
-  DISALLOW_COPY_AND_ASSIGN(UTF16TextLength);
-};
-
-UTF16TextLength::UTF16TextLength()
-    : utf16_length_(0) {
-}
-
-UTF16TextLength::~UTF16TextLength() {
-}
-
-void UTF16TextLength::Append(char c) {
-  // Append the given character and try converting the UTF-8 characters in this
-  // buffer to Unicode codepoints. If this buffer includes a Unicode codepoint,
-  // get the number of UTF-16 characters representing this codepoint and advance
-  // the position.
-  int code = 0;
-  int index = 0;
-  utf8_text_.push_back(c);
-  U8_NEXT(utf8_text_.data(), index, static_cast<int>(utf8_text_.length()),
-          code);
-  if (code != U_SENTINEL) {
-    utf8_text_.clear();
-    utf16_length_ += U16_LENGTH(code);
-  }
-}
-
-// A class that encapsulates a hyphenation query. This class owns resources
-// temporarily needed for hyphenating one word, and deletes them when it is
-// deleted as listed in the following snippet.
-//
-//   std::vector<int> hyphens;
-//   QUery query(UTF8ToUTF16("hyphenate"));
-//   query.Hyphenate(dict, &hyphens);
-//
-class Query {
- public:
-  explicit Query(const string16& word);
-  ~Query();
-
-  // Hyphenates a word with the specified dictionary. This function hyphenates
-  // the word provided to its constructor and returns a list of hyphenation
-  // points, positions where we can insert hyphens.
-  bool Hyphenate(HyphenDict* dictionary, std::vector<int>* hyphen_offsets);
-
- private:
-  // A word to be hyphenated.
-  std::string word_utf8_;
-
-  // Return variables from the hyphen library.
-  scoped_ptr<char[]> hyphen_vector_;
-  char** rep_;
-  int* pos_;
-  int* cut_;
-
-  DISALLOW_COPY_AND_ASSIGN(Query);
-};
-
-Query::Query(const string16& word)
-    : rep_(NULL),
-      pos_(NULL),
-      cut_(NULL) {
-  // Remove trailing punctuation characters. WebKit does not remove these
-  // characters when it hyphenates a word. These characters prevent the hyphen
-  // library from applying some rules, i.e. they prevent the library from adding
-  // hyphens.
-  DCHECK(!word.empty());
-  const char16* data = word.data();
-  int length = static_cast<int>(word.length());
-  while (length > 0) {
-    int previous = length;
-    int code = 0;
-    U16_PREV(data, 0, previous, code);
-    UErrorCode error = U_ZERO_ERROR;
-    if (uscript_getScript(code, &error) != USCRIPT_COMMON)
-      break;
-    length = previous;
-  }
-  UTF16ToUTF8(word.c_str(), length, &word_utf8_);
-  // Create a hyphen vector used by hnj_hyphen_hyphenate2(). We allocate a
-  // buffer of |word_.length()| + 5 as written in Line 112 of
-  // <http://cs.chromium.org/src/third_party/hyphen/hyphen.h>.
-  hyphen_vector_.reset(new char[word_utf8_.length() + 5]);
-}
-
-Query::~Query() {
-  if (rep_) {
-    for (size_t i = 0; i < word_utf8_.length(); ++i) {
-      if (rep_[i])
-        free(rep_[i]);
-    }
-    free(rep_);
-  }
-  if (pos_)
-    free(pos_);
-  if (cut_)
-    free(cut_);
-}
-
-bool Query::Hyphenate(HyphenDict* dictionary,
-                      std::vector<int>* hyphen_offsets) {
-  DCHECK(dictionary);
-  DCHECK(hyphen_offsets);
-
-  int error_code = hnj_hyphen_hyphenate2(dictionary,
-                                         word_utf8_.data(),
-                                         static_cast<int>(word_utf8_.length()),
-                                         hyphen_vector_.get(),
-                                         NULL,
-                                         &rep_,
-                                         &pos_,
-                                         &cut_);
-  if (error_code)
-    return false;
-
-  // WebKit needs hyphenation points counted in UTF-16 characters. On the other
-  // hand, the hyphen library returns hyphenation points counted in UTF-8
-  // characters. We increamentally convert hyphenation points in UTF-8
-  // characters to hyphenation points in UTF-16 characters and write the
-  // converted hyphenation points to the output vector.
-  UTF16TextLength text_length;
-  hyphen_offsets->clear();
-  for (size_t i = 0; i < word_utf8_.length(); ++i) {
-    text_length.Append(word_utf8_[i]);
-    if (hyphen_vector_[i] & 1)
-      hyphen_offsets->push_back(text_length.utf16_length());
-  }
-  return !hyphen_offsets->empty();
-}
-
-}  // namespace
-
-namespace content {
-
-Hyphenator::Hyphenator(base::PlatformFile file)
-    : dictionary_(NULL),
-      dictionary_file_(base::FdopenPlatformFile(file, "r")),
-      result_(0) {
-}
-
-Hyphenator::~Hyphenator() {
-  if (dictionary_)
-    hnj_hyphen_free(dictionary_);
-}
-
-bool Hyphenator::Initialize() {
-  if (dictionary_)
-    return true;
-
-  if (!dictionary_file_.get())
-    return false;
-  dictionary_ = hnj_hyphen_load_file(dictionary_file_.get());
-  return !!dictionary_;
-}
-
-bool Hyphenator::Attach(RenderThread* thread, const string16& locale) {
-  if (!thread)
-    return false;
-  locale_.assign(locale);
-  thread->AddObserver(this);
-  return thread->Send(new HyphenatorHostMsg_OpenDictionary(locale));
-}
-
-bool Hyphenator::CanHyphenate(const string16& locale) {
-  return !locale_.compare(locale);
-}
-
-size_t Hyphenator::ComputeLastHyphenLocation(const string16& word,
-                                             size_t before_index) {
-  if (!Initialize() || word.empty())
-    return 0;
-
-  // Call the hyphen library to get all hyphenation points, i.e. positions where
-  // we can insert hyphens. When WebKit finds a line-break, it calls this
-  // function twice or more with the same word to find the best hyphenation
-  // point. To avoid calling the hyphen library twice or more with the same
-  // word, we cache the last query.
-  if (word_ != word) {
-    word_ = word;
-    Query query(word);
-    result_ = query.Hyphenate(dictionary_, &hyphen_offsets_);
-  }
-  if (!result_)
-    return 0;
-  for (std::vector<int>::reverse_iterator it = hyphen_offsets_.rbegin();
-       it != hyphen_offsets_.rend(); ++it) {
-    if (static_cast<size_t>(*it) < before_index)
-      return *it;
-  }
-  return 0;
-}
-
-bool Hyphenator::OnControlMessageReceived(const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(Hyphenator, message)
-    IPC_MESSAGE_HANDLER(HyphenatorMsg_SetDictionary, OnSetDictionary)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
-void Hyphenator::OnSetDictionary(IPC::PlatformFileForTransit file) {
-  base::PlatformFile rule_file =
-      IPC::PlatformFileForTransitToPlatformFile(file);
-  if (rule_file == base::kInvalidPlatformFileValue)
-    return;
-  // Delete the current dictionary and save the given file to this object. We
-  // initialize the hyphen library the first time when WebKit actually
-  // hyphenates a word, i.e. when WebKit calls the ComputeLastHyphenLocation
-  // function. (WebKit does not always hyphenate words even when it calls the
-  // CanHyphenate function, e.g. WebKit does not have to hyphenate words when it
-  // does not have to break text into lines.)
-  if (dictionary_) {
-    hnj_hyphen_free(dictionary_);
-    dictionary_ = NULL;
-  }
-  dictionary_file_.Set(base::FdopenPlatformFile(rule_file, "r"));
-}
-
-}  // namespace content