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