Retry: sync: Gracefully handle early shutdown

sync/engine/net/server_connection_manager.h

 // Copyright 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 SYNC_ENGINE_NET_SERVER_CONNECTION_MANAGER_H_
 #define SYNC_ENGINE_NET_SERVER_CONNECTION_MANAGER_H_
 
 #include <iosfwd>
 #include <string>
 
 #include "base/atomicops.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "base/strings/string_util.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/threading/thread_checker.h"
 #include "sync/base/sync_export.h"
+#include "sync/internal_api/public/base/cancelation_observer.h"
 #include "sync/syncable/syncable_id.h"
 
 namespace sync_pb {
 class ClientToServerMessage;
 }
 
 namespace syncer {
 
+class CancelationSignal;
+
 namespace syncable {
 class Directory;
 }
 
 static const int32 kUnsetResponseCode = -1;
 static const int32 kUnsetContentLength = -1;
 static const int32 kUnsetPayloadLength = -1;
 
 // HttpResponse gathers the relevant output properties of an HTTP request.
 // Depending on the value of the server_status code, response_code, and
@@ skipping 81 matching lines @@
   virtual ~ScopedServerStatusWatcher();
  private:
   ServerConnectionManager* const conn_mgr_;
   HttpResponse* const response_;
   DISALLOW_COPY_AND_ASSIGN(ScopedServerStatusWatcher);
 };
 
 // Use this class to interact with the sync server.
 // The ServerConnectionManager currently supports POSTing protocol buffers.
 //
-class SYNC_EXPORT_PRIVATE ServerConnectionManager {
+class SYNC_EXPORT_PRIVATE ServerConnectionManager : public CancelationObserver {
  public:
   // buffer_in - will be POSTed
   // buffer_out - string will be overwritten with response
   struct PostBufferParams {
     std::string buffer_in;
     std::string buffer_out;
     HttpResponse response;
   };
 
   // Abstract class providing network-layer functionality to the
@@ skipping 37 matching lines @@
     ServerConnectionManager* scm_;
 
    private:
     int ReadResponse(void* buffer, int length);
     int ReadResponse(std::string* buffer, int length);
   };
 
   ServerConnectionManager(const std::string& server,
                           int port,
                           bool use_ssl,
-                          bool use_oauth2_token);
+                          bool use_oauth2_token,
+                          CancelationSignal* cancelation_signal);
 
   virtual ~ServerConnectionManager();
 
   // POSTS buffer_in and reads a response into buffer_out. Uses our currently
   // set auth token in our headers.
   //
   // Returns true if executed successfully.
   virtual bool PostBufferWithCachedAuth(PostBufferParams* params,
                                         ScopedServerStatusWatcher* watcher);
 
@@ skipping 15 matching lines @@
   std::string GetServerHost() const;
 
   // Factory method to create an Connection object we can use for
   // communication with the server.
   virtual Connection* MakeConnection();
 
   // Closes any active network connections to the sync server.
   // We expect this to get called on a different thread than the valid
   // ThreadChecker thread, as we want to kill any pending http traffic without
   // having to wait for the request to complete.
-  virtual void TerminateAllIO();
+  virtual void OnSignalReceived() OVERRIDE FINAL;
 
   void set_client_id(const std::string& client_id) {
     DCHECK(thread_checker_.CalledOnValidThread());
     DCHECK(client_id_.empty());
     client_id_.assign(client_id);
   }
 
   // Sets a new auth token and time.
   bool SetAuthToken(const std::string& auth_token);
 
@@ skipping 102 matching lines @@
     ~ScopedConnectionHelper();
     Connection* get();
    private:
     ServerConnectionManager* manager_;
     scoped_ptr<Connection> connection_;
     DISALLOW_COPY_AND_ASSIGN(ScopedConnectionHelper);
   };
 
   void NotifyStatusChanged();
 
+  CancelationSignal* const cancelation_signal_;
+  bool signal_handler_registered_;
+
   DISALLOW_COPY_AND_ASSIGN(ServerConnectionManager);
 };
 
 std::ostream& operator<<(std::ostream& s, const struct HttpResponse& hr);
 
 }  // namespace syncer
 
 #endif  // SYNC_ENGINE_NET_SERVER_CONNECTION_MANAGER_H_