net/http/disk_cache_based_quic_server_info.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_HTTP_DISK_CACHE_BASED_QUIC_SERVER_INFO_H_
   6 #define NET_HTTP_DISK_CACHE_BASED_QUIC_SERVER_INFO_H_
   7
   8 #include <string>
   9
  10 #include "base/memory/ref_counted.h"
  11 #include "base/memory/weak_ptr.h"
  12 #include "base/threading/non_thread_safe.h"
  13 #include "base/time/time.h"
  14 #include "net/base/completion_callback.h"
  15 #include "net/disk_cache/disk_cache.h"
  16 #include "net/quic/crypto/quic_server_info.h"
  17
  18 namespace net {
  19
  20 class HttpCache;
  21 class IOBuffer;
  22 class QuicServerId;
  23
  24 // DiskCacheBasedQuicServerInfo fetches information about a QUIC server from
  25 // our standard disk cache. Since the information is defined to be
  26 // non-sensitive, it's ok for us to keep it on disk.
  27 class NET_EXPORT_PRIVATE DiskCacheBasedQuicServerInfo
  28     : public QuicServerInfo,
  29       public NON_EXPORTED_BASE(base::NonThreadSafe) {
  30  public:
  31   DiskCacheBasedQuicServerInfo(const QuicServerId& server_id,
  32                                HttpCache* http_cache);
  33
  34   // QuicServerInfo implementation.
  35   void Start() override;
  36   int WaitForDataReady(const CompletionCallback& callback) override;
  37   void CancelWaitForDataReadyCallback() override;
  38   bool IsDataReady() override;
  39   bool IsReadyToPersist() override;
  40   void Persist() override;
  41   void OnExternalCacheHit() override;
  42
  43  private:
  44   struct CacheOperationDataShim;
  45
  46   enum State {
  47     GET_BACKEND,
  48     GET_BACKEND_COMPLETE,
  49     OPEN,
  50     OPEN_COMPLETE,
  51     READ,
  52     READ_COMPLETE,
  53     WAIT_FOR_DATA_READY_DONE,
  54     CREATE_OR_OPEN,
  55     CREATE_OR_OPEN_COMPLETE,
  56     WRITE,
  57     WRITE_COMPLETE,
  58     SET_DONE,
  59     NONE,
  60   };
  61
  62   // Enum to track number of times data read/parse/write API calls of
  63   // QuicServerInfo to and from disk cache is called.
  64   enum QuicServerInfoAPICall {
  65     QUIC_SERVER_INFO_START = 0,
  66     QUIC_SERVER_INFO_WAIT_FOR_DATA_READY = 1,
  67     QUIC_SERVER_INFO_PARSE = 2,
  68     QUIC_SERVER_INFO_WAIT_FOR_DATA_READY_CANCEL = 3,
  69     QUIC_SERVER_INFO_READY_TO_PERSIST = 4,
  70     QUIC_SERVER_INFO_PERSIST = 5,
  71     QUIC_SERVER_INFO_EXTERNAL_CACHE_HIT = 6,
  72     QUIC_SERVER_INFO_NUM_OF_API_CALLS = 7,
  73   };
  74
  75   // Enum to track failure reasons to read/load/write of QuicServerInfo to
  76   // and from disk cache.
  77   enum FailureReason {
  78     WAIT_FOR_DATA_READY_INVALID_ARGUMENT_FAILURE = 0,
  79     GET_BACKEND_FAILURE = 1,
  80     OPEN_FAILURE = 2,
  81     CREATE_OR_OPEN_FAILURE = 3,
  82     PARSE_NO_DATA_FAILURE = 4,
  83     PARSE_FAILURE = 5,
  84     READ_FAILURE = 6,
  85     READY_TO_PERSIST_FAILURE = 7,
  86     PERSIST_NO_BACKEND_FAILURE = 8,
  87     WRITE_FAILURE = 9,
  88     NO_FAILURE = 10,
  89     NUM_OF_FAILURES = 11,
  90   };
  91
  92   ~DiskCacheBasedQuicServerInfo() override;
  93
  94   // Persists |pending_write_data_| if it is not empty, otherwise serializes the
  95   // data and pesists it.
  96   void PersistInternal();
  97
  98   std::string key() const;
  99
 100   // The |unused| parameter is a small hack so that we can have the
 101   // CacheOperationDataShim object owned by the Callback that is created for
 102   // this method.  See comment above CacheOperationDataShim for details.
 103   void OnIOComplete(CacheOperationDataShim* unused, int rv);
 104
 105   int DoLoop(int rv);
 106
 107   int DoGetBackendComplete(int rv);
 108   int DoOpenComplete(int rv);
 109   int DoReadComplete(int rv);
 110   int DoWriteComplete(int rv);
 111   int DoCreateOrOpenComplete(int rv);
 112
 113   int DoGetBackend();
 114   int DoOpen();
 115   int DoRead();
 116   int DoWrite();
 117   int DoCreateOrOpen();
 118
 119   // DoWaitForDataReadyDone is the terminal state of the read operation.
 120   int DoWaitForDataReadyDone();
 121
 122   // DoSetDone is the terminal state of the write operation.
 123   int DoSetDone();
 124
 125   // Tracks in a histogram the number of times data read/parse/write API calls
 126   // of QuicServerInfo to and from disk cache is called.
 127   void RecordQuicServerInfoStatus(QuicServerInfoAPICall call);
 128
 129   // Tracks in a histogram the failure reasons to read/load/write of
 130   // QuicServerInfo to and from disk cache. It also saves the |failure| in
 131   // |last_failure_|.
 132   void RecordQuicServerInfoFailure(FailureReason failure);
 133
 134   // Tracks in a histogram if |last_failure_| is not NO_FAILURE.
 135   void RecordLastFailure();
 136
 137   CacheOperationDataShim* data_shim_;  // Owned by |io_callback_|.
 138   CompletionCallback io_callback_;
 139   State state_;
 140   bool ready_;
 141   bool found_entry_;  // Controls the behavior of DoCreateOrOpen.
 142   std::string new_data_;
 143   std::string pending_write_data_;
 144   const QuicServerId server_id_;
 145   HttpCache* const http_cache_;
 146   disk_cache::Backend* backend_;
 147   disk_cache::Entry* entry_;
 148   CompletionCallback wait_for_ready_callback_;
 149   scoped_refptr<IOBuffer> read_buffer_;
 150   scoped_refptr<IOBuffer> write_buffer_;
 151   std::string data_;
 152   base::TimeTicks load_start_time_;
 153   FailureReason last_failure_;
 154
 155   base::WeakPtrFactory<DiskCacheBasedQuicServerInfo> weak_factory_;
 156
 157   DISALLOW_COPY_AND_ASSIGN(DiskCacheBasedQuicServerInfo);
 158 };
 159
 160 }  // namespace net
 161
 162 #endif  // NET_HTTP_DISK_CACHE_BASED_QUIC_SERVER_INFO_H_