Implement MediaMetadata artwork in content

content/public/common/media_metadata.cc

 // 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.
 
 #include "content/public/common/media_metadata.h"
 
+#include <algorithm>
+#include <iterator>
+
 namespace content {
 
+namespace {
+
+const size_t kMaxArtworkSrcLength = 4 * 1024;
+// Maximum type length of Artwork, which conforms to RFC 4288
+// (https://tools.ietf.org/html/rfc4288).
+const size_t kMaxArtworkTypeLength = 2 * 127 + 1;
+const size_t kMaxNumberOfArtworkSizes = 10;
+
+}  // anonymous namespace
+
 const size_t MediaMetadata::kMaxIPCStringLength = 4 * 1024;
+const size_t MediaMetadata::kMaxNumberOfArtworkImages = 10;
 
 MediaMetadata::MediaMetadata() = default;
 
 MediaMetadata::~MediaMetadata() = default;
 
+MediaMetadata::MediaMetadata(const MediaMetadata& other) = default;
+
 bool MediaMetadata::operator==(const MediaMetadata& other) const {
-  return title == other.title && artist == other.artist && album == other.album;
+  return title == other.title && artist == other.artist &&
+      album == other.album && artwork == other.artwork;
 }
 
 bool MediaMetadata::operator!=(const MediaMetadata& other) const {
   return !this->operator==(other);
 }
 
+base::Optional<MediaMetadata::Artwork> MediaMetadata::SanitizeArtwork(

[DaleCurtis, 2016/06/29 17:20:20]

What's the point of sanitizing the artwork? Why not just fail if invalid options
are used?

[Zhiqiang Zhang (Slow), 2016/06/29 19:16:13]

The artwork come from blink, and can be anything, so we sanitize it before
sending to the browser through IPC.

Sometimes it may be legal but improper to be sent through IPC (e.g. src is too
long), so I think we should not fail.

+    const MediaMetadata::Artwork& artwork) {
+  if (!artwork.src.is_valid() || !artwork.src.IsStandard() ||
+      (!artwork.src.SchemeIsHTTPOrHTTPS() &&
+       !artwork.src.SchemeIsFile()) ||
+      artwork.src.spec().size() > kMaxArtworkSrcLength) {
+    return base::nullopt;
+  }
+  // Early return if artwork is sane.
+  if (artwork.type.string().size() <= kMaxArtworkTypeLength &&
+      artwork.sizes.size() <= kMaxNumberOfArtworkSizes)

[DaleCurtis, 2016/06/29 17:20:20]

Needs {}

[Zhiqiang Zhang (Slow), 2016/06/29 19:16:13]

Done.

+    return artwork;
+
+  Artwork sanitized_artwork;
+  sanitized_artwork.src = artwork.src;
+  sanitized_artwork.type = artwork.type.is_null() ?
+      base::NullableString16() :
+      base::NullableString16(
+          artwork.type.string().substr(0, kMaxArtworkTypeLength),
+          false);
+  for (size_t i = 0;

[DaleCurtis, 2016/06/29 17:20:20]

{}

[Zhiqiang Zhang (Slow), 2016/06/29 19:16:13]

Done.

+       i < std::min(artwork.sizes.size(), kMaxNumberOfArtworkSizes);
+       ++i)
+    sanitized_artwork.sizes.push_back(artwork.sizes[i]);
+
+  return sanitized_artwork;
+}
+
 }  // namespace content