Adding support for forced URLs to TopSites.

chrome/browser/history/top_sites_cache.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 CHROME_BROWSER_HISTORY_TOP_SITES_CACHE_H_
 #define CHROME_BROWSER_HISTORY_TOP_SITES_CACHE_H_
 
 #include <map>
 #include <utility>
 
@@ skipping 24 matching lines @@
 //   ignoring "?query#ref".
 // For the latter two "URL prefix matches", we prefer the match that is closest
 // to input URL, w.r.t. path hierarchy.
 
 // TopSitesCache caches the top sites and thumbnails for TopSites.
 class TopSitesCache {
  public:
   TopSitesCache();
   ~TopSitesCache();
 
-  // The top sites.
+  // Set the top sites. In |top_sites| all forced URLs must appear before
+  // non-forced URLs. This is only checked in debug.
   void SetTopSites(const MostVisitedURLList& top_sites);
   const MostVisitedURLList& top_sites() const { return top_sites_; }
 
   // The thumbnails.
   void SetThumbnails(const URLToImagesMap& images);
   const URLToImagesMap& images() const { return images_; }
 
   // Returns the thumbnail as an Image for the specified url. This adds an entry
   // for |url| if one has not yet been added.
   Images* GetImage(const GURL& url);
@@ skipping 16 matching lines @@
   // ignoring "?query#ref". Returns the resulting canonical URL if match is
   // found, otherwise returns an empty GURL.
   GURL GetGeneralizedCanonicalURL(const GURL& url) const;
 
   // Returns true if |url| is known.
   bool IsKnownURL(const GURL& url) const;
 
   // Returns the index into |top_sites_| for |url|.
   size_t GetURLIndex(const GURL& url) const;
 
+  // Returns the number of non-forced URLs in the cache.
+  size_t GetNumNonForcedURLs() const;
+
+  // Returns the number of forced URLs in the cache.
+  size_t GetNumForcedURLs() const;
+
  private:
   // The entries in CanonicalURLs, see CanonicalURLs for details. The second
   // argument gives the index of the URL into MostVisitedURLs redirects.
   typedef std::pair<MostVisitedURL*, size_t> CanonicalURLEntry;
 
   // Comparator used for CanonicalURLs.
   class CanonicalURLComparator {
    public:
     bool operator()(const CanonicalURLEntry& e1,
                     const CanonicalURLEntry& e2) const {
@@ skipping 18 matching lines @@
   // This is used to map from redirect url to the MostVisitedURL the redirect is
   // from. Ideally this would be map<GURL, size_t> (second param indexing into
   // top_sites_), but this results in duplicating all redirect urls. As some
   // sites have a lot of redirects, we instead use the MostVisitedURL* and the
   // index of the redirect as the key, and the index into top_sites_ as the
   // value. This way we aren't duplicating GURLs. CanonicalURLComparator
   // enforces the ordering as if we were using GURLs.
   typedef std::map<CanonicalURLEntry, size_t,
                    CanonicalURLComparator> CanonicalURLs;
 
+  // Count the number of forced URLs.
+  void CountForcedURLs();
+
   // Generates the set of canonical urls from |top_sites_|.
   void GenerateCanonicalURLs();
 
   // Stores a set of redirects. This is used by GenerateCanonicalURLs.
   void StoreRedirectChain(const RedirectList& redirects, size_t destination);
 
   // Returns the iterator into |canonical_urls_| for the |url|.
   CanonicalURLs::const_iterator GetCanonicalURLsIterator(const GURL& url) const;
 
   // Returns the GURL corresponding to an iterator in |canonical_urls_|.
   const GURL& GetURLFromIterator(CanonicalURLs::const_iterator it) const;
 
-  // The top sites.
+  // The number of top sites with forced URLs.
+  size_t num_forced_urls_;
+
+  // The top sites. This list must always contain the forced URLs first followed
+  // by the non-forced URLs. This is not strictly enforced but is checked in
+  // debug.
   MostVisitedURLList top_sites_;
 
   // The images. These map from canonical url to image.
   URLToImagesMap images_;
 
   // Generated from the redirects to and from the most visited pages. See
   // description above typedef for details.
   CanonicalURLs canonical_urls_;
 
   // Helper to clear "?query#ref" from any GURL. This is set in the constructor
   // and never modified after.
   GURL::Replacements clear_query_ref_;
 
   // Helper to clear "/path?query#ref" from any GURL. This is set in the
   // constructor and never modified after.
   GURL::Replacements clear_path_query_ref_;
 
   DISALLOW_COPY_AND_ASSIGN(TopSitesCache);
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_TOP_SITES_CACHE_H_