Adds a hy-phen-ator.

content/renderer/hyphenator/hyphenator.h

+// 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.
+
+#ifndef CONTENT_RENDERER_HYPHENATOR_HYPHENATOR_H_
+#define CONTENT_RENDERER_HYPHENATOR_HYPHENATOR_H_
+#pragma once
+
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/platform_file.h"
+#include "base/string16.h"
+#include "content/common/content_export.h"
+
+namespace file_util {
+class MemoryMappedFile;
+}
+

[jochen (gone - plz use gerrit), 2012/07/02 15:33:01]

all code in content/ should go into the namespace content

[Hironori Bono, 2012/07/10 09:22:09]

Done. Thanks for your comment. (I did not notice it.)

+typedef struct _HyphenDict HyphenDict;
+
+// A class that hyphenates a word. This class encapsulates the hyphen library
+// and manages resources used by the library. When this class uses a huge
+// dictionary, it takes lots of memory. A renderer should create this object

[tony, 2012/06/28 20:06:44]

Nit: Would be nice to give actual size estimates here.

+// only when it renders a page that needs hyphenation and deletes it when it
+// moves to a page that does not need hyphenation as listed in the following
+// snippet.
+//
+//   base::PlatformFile file("hyphen.us");
+//   scoped_ptr<Hyphenator> hyphenator(new Hyphenator(file));
+//   size_t pos = hyphenator->ComputeLastHyphenLocation("organize", 8);
+//   ...
+//   hyphenator.reset();
+//
+class CONTENT_EXPORT Hyphenator {

[jochen (gone - plz use gerrit), 2012/07/02 15:33:01]

why is this a CONTENT_EXPORT class if it's not in content/public?

[Hironori Bono, 2012/07/10 09:22:09]

Even though this class is not a public one, it is used by content_unittests.
That is, this CONTENT_EXPORT is just for avoiding build breaks in building
content_unittests on shared builders. Is it possible to give me better ideas?

[jochen (gone - plz use gerrit), 2012/07/10 09:46:06]

Usually, we have different macros for this case (see
http://www.chromium.org/developers/how-tos/component-build at the bottom).
content/ currently does not, so this is fine. I filed http://crbug.com/136495
for this

+ public:
+  explicit Hyphenator(base::PlatformFile file);
+  ~Hyphenator();
+
+  // Initializes the hyphen library and allocates resources needed for
+  // hyphenation.
+  bool Initialize();
+
+  // Returns the last hyphenation point, the position where we can insert a
+  // hyphen, before the given position. If there are not any hyphenation points,
+  // this function returns 0.
+  size_t ComputeLastHyphenLocation(const string16& word, size_t before_index);
+
+ private:
+  // The dictionary used by the hyphen library.
+  HyphenDict* dictionary_;
+
+  // The dictionary file and its memory-mapping object. (Our copy of the hyphen
+  // library uses a memory-mapped file opened by a browser so renderers can use
+  // it without opening the file.)
+  base::PlatformFile rule_file_;
+  scoped_ptr<file_util::MemoryMappedFile> rule_map_;
+
+  // A cached result. WebKit often calls ComputeLastHyphenLocation with the same
+  // word multiple times to find the best hyphenation point when it finds a line
+  // break. On the other hand, the hyphen library returns all hyphenation points
+  // for a word. This class caches the hyphenation points returned by the hyphen
+  // library to avoid calling the library multiple times.
+  string16 word_;
+  bool result_;
+  std::vector<int> hyphen_offsets_;
+};

[jochen (gone - plz use gerrit), 2012/07/02 15:33:01]

DISALLOW_COPY_AND_ASSIGN?

[Hironori Bono, 2012/07/10 09:22:09]

Done. Thanks for noticing it.

+
+#endif  // CONTENT_RENDERER_HYPHENATOR_HYPHENATOR_H_