net/sdch/sdch_owner.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_SDCH_SDCH_OWNER_H_
   6 #define NET_SDCH_SDCH_OWNER_H_
   7
   8 #include <string>
   9
  10 #include "base/memory/memory_pressure_listener.h"
  11 #include "net/base/sdch_observer.h"
  12 #include "net/url_request/sdch_dictionary_fetcher.h"
  13
  14 class GURL;
  15
  16 namespace base {
  17 class Clock;
  18 }
  19
  20 namespace net {
  21 class SdchManager;
  22 class URLRequestContext;
  23
  24 // This class owns the SDCH objects not owned as part of URLRequestContext, and
  25 // exposes interface for setting SDCH policy.  It should be instantiated by
  26 // the net/ embedder.
  27 // TODO(rdsmith): Implement dictionary prioritization.
  28 class NET_EXPORT SdchOwner : public net::SdchObserver {
  29  public:
  30   static const size_t kMaxTotalDictionarySize;
  31   static const size_t kMinSpaceForDictionaryFetch;
  32
  33   // Consumer must guarantee that |sdch_manager| and |context| outlive
  34   // this object.
  35   SdchOwner(net::SdchManager* sdch_manager, net::URLRequestContext* context);
  36   ~SdchOwner() override;
  37
  38   // Defaults to kMaxTotalDictionarySize.
  39   void SetMaxTotalDictionarySize(size_t max_total_dictionary_size);
  40
  41   // Defaults to kMinSpaceForDictionaryFetch.
  42   void SetMinSpaceForDictionaryFetch(size_t min_space_for_dictionary_fetch);
  43
  44   // SdchObserver implementation.
  45   void OnDictionaryUsed(SdchManager* manager,
  46                         const std::string& server_hash) override;
  47   void OnGetDictionary(net::SdchManager* manager,
  48                        const GURL& request_url,
  49                        const GURL& dictionary_url) override;
  50   void OnClearDictionaries(net::SdchManager* manager) override;
  51
  52   // Implementation detail--this is the pathway through which the
  53   // fetcher informs the SdchOwner that it's gotten the dictionary.
  54   // Public for testing.
  55   void OnDictionaryFetched(const std::string& dictionary_text,
  56                            const GURL& dictionary_url,
  57                            const net::BoundNetLog& net_log);
  58
  59   void SetClockForTesting(scoped_ptr<base::Clock> clock);
  60
  61  private:
  62   // For each active dictionary, stores local info.
  63   // Indexed by server hash.
  64   struct DictionaryInfo {
  65     base::Time last_used;
  66     int use_count;
  67     size_t size;
  68
  69     DictionaryInfo() : use_count(0), size(0) {}
  70     DictionaryInfo(const base::Time& last_used, size_t size)
  71         : last_used(last_used), use_count(0), size(size) {}
  72     DictionaryInfo(const DictionaryInfo& rhs) = default;
  73     DictionaryInfo& operator=(const DictionaryInfo& rhs) = default;
  74   };
  75
  76   void OnMemoryPressure(
  77       base::MemoryPressureListener::MemoryPressureLevel level);
  78
  79   net::SdchManager* manager_;
  80   net::SdchDictionaryFetcher fetcher_;
  81
  82   std::map<std::string, DictionaryInfo> local_dictionary_info_;
  83   size_t total_dictionary_bytes_;
  84
  85   scoped_ptr<base::Clock> clock_;
  86
  87   size_t max_total_dictionary_size_;
  88   size_t min_space_for_dictionary_fetch_;
  89
  90 #if defined(OS_CHROMEOS)
  91   // For debugging http://crbug.com/454198; remove when resolved.
  92   unsigned int destroyed_;
  93 #endif
  94
  95   // TODO(rmcilroy) Add back memory_pressure_listener_ when
  96   // http://crbug.com/447208 is fixed
  97
  98   DISALLOW_COPY_AND_ASSIGN(SdchOwner);
  99 };
 100
 101 }  // namespace net
 102
 103 #endif  // NET_SDCH_SDCH_OWNER_H_