Implement API for accessing fonts installed locally on the system.

content/browser/font_access/font_access_service_impl.h

+// Copyright 2016 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_BROWSER_FONT_ACCESS_FONT_ACCESS_SERVICE_IMPL_H_
+#define CONTENT_BROWSER_FONT_ACCESS_FONT_ACCESS_SERVICE_IMPL_H_
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "content/browser/font_access/font_getter.h"
+#include "content/common/font_access/font_access_service.mojom.h"
+#include "mojo/public/cpp/bindings/strong_binding.h"
+
+namespace content {
+
+class FontAccessServiceImpl : public FontAccessService {
+ public:
+  FontAccessServiceImpl(
+      base::Callback<scoped_ptr<FontCacheMap>(void)> getter,
+      mojo::InterfaceRequest<FontAccessService> request);
+  ~FontAccessServiceImpl() override;
+
+  // Returns a list of FontAccessDescriptions on the callback.

[nasko, 2016/02/10 23:43:26]

nit: Technically, it returns void. It sends that list to the
GetFontListCallback, right?
nit: s/on the callback/to the callback/

[Daniel Nishi, 2016/02/11 00:23:50]

That is correct.

Done.

+  void GetFontList(const GetFontListCallback& callback) override;
+
+  // Returns a Mojo SharedBuffer of the font's binary on the callback.
+  void GetFontData(const mojo::String& family,
+                   const mojo::String& style,
+                   const GetFontDataCallback& callback) override;
+
+  static void Create(
+      mojo::InterfaceRequest<FontAccessService> request);
+
+ private:
+  // Used to pass around all the information about a blob from disk.
+  struct BlobInfo {
+    BlobInfo();
+    ~BlobInfo();
+
+    uint64_t size;
+    base::Time last_modified;
+    std::string mime;
+    bool is_valid;
+  };
+
+  // Clobbers the cache and then fetches the font list.
+  void GetFontListFromCache(const GetFontListCallback& callback);
+
+  // Pulls the font binary path from the cache and returns the font binary in a

[nasko, 2016/02/10 23:43:26]

nit: When talking about paths, one usually thinks of filesystem ones. I don't
see such a type here, only family and style. Maybe define somewhere in comment
what is meant by "font binary path", so it is clear to the reader.

[Daniel Nishi, 2016/02/11 00:23:50]

It is referring to a file system one. We're caching a mapping of these font
specifiers to the font file system path.

+  // shared buffer on the callback, if it exists. If it does not exist, returns
+  // an empty shared buffer on the callback.
+  void GetFontDataInternal(const std::string& family,
+                           const std::string& style,
+                           const GetFontDataCallback& callback);
+  // Returns the font binary path if it exists in the cache.

[nasko, 2016/02/10 23:43:26]

nit: Empty line before the comment.

[Daniel Nishi, 2016/02/11 00:23:50]

Done.

+  // Otherwise, returns an empty string.
+  std::string FindPathInCache(const std::string& family,
+                              const std::string& style);
+
+  void GetFileDataCallback(
+      const FontAccessService::GetFontDataCallback& callback,
+      const std::string& path,
+      const BlobInfo info);
+
+  void ClobberCacheAndReply(const base::Closure closure);
+  void SwapCacheAndReply(const base::Closure closure, scoped_ptr<FontCacheMap>);
+
+  static BlobInfo GetFileInfo(const std::string path);

[nasko, 2016/02/10 23:43:26]

sytle: static methods go first in ordering of the class methods.

[Daniel Nishi, 2016/02/11 00:23:50]

Done.

+
+  // Returns a shared buffer with the binary data from a file path.
+  static mojo::ScopedSharedBufferHandle GetSharedBuffer(const std::string path,
+                                                        uint64_t size);
+  static void PassBufferAndSize(
+      const FontAccessService::GetFontDataCallback& callback,
+      uint64_t size,
+      mojo::ScopedSharedBufferHandle handle);
+
+  scoped_ptr<FontCacheMap> font_cache_map_;
+  // The binding between this object and the other end of the pipe.
+  mojo::StrongBinding<FontAccessService> binding_;
+  base::Callback<scoped_ptr<FontCacheMap>(void)> cache_map_getter_;
+  base::WeakPtrFactory<FontAccessServiceImpl> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(FontAccessServiceImpl);
+};
+
+}  // namespace content
+
+#endif // CONTENT_BROWSER_FONT_ACCESS_FONT_ACCESS_SERVICE_IMPL_H_