Initial commit of sync engine code to browser/sync....

chrome/browser/sync/syncable/directory_manager.h

+// Copyright (c) 2009 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.
+//
+// This used to do a lot of TLS-based management of multiple Directory objects.
+// We now can access Directory objects from any thread for general purpose
+// operations and we only ever have one Directory, so this class isn't doing
+// anything too fancy besides keeping calling and access conventions the same
+// for now.
+// TODO(timsteele): We can probably nuke this entire class and use raw
+// Directory objects everywhere.
+#ifndef CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_MANAGER_H_
+#define CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_MANAGER_H_
+
+#include <pthread.h>
+
+#include <vector>
+
+#include "base/atomicops.h"
+#include "base/basictypes.h"
+#include "chrome/browser/sync/syncable/dir_open_result.h"
+#include "chrome/browser/sync/syncable/path_name_cmp.h"
+#include "chrome/browser/sync/syncable/syncable.h"
+#include "chrome/browser/sync/util/event_sys.h"
+#include "chrome/browser/sync/util/sync_types.h"
+
+namespace sync_api { class BaseTransaction; }
+
+namespace syncable {
+
+struct DirectoryManagerEvent {
+  enum {
+    OPEN_FAILED,
+    OPENED,
+    CLOSED,
+    CLOSED_ALL,
+    SHUTDOWN,
+  } what_happened;
+  PathString dirname;
+  DirOpenResult error;  // Only for OPEN_FAILED.
+  typedef DirectoryManagerEvent EventType;
+  static inline bool IsChannelShutdownEvent(const EventType& event) {
+    return SHUTDOWN == event.what_happened;
+  }
+};
+
+DirectoryManagerEvent DirectoryManagerShutdownEvent();
+
+class DirectoryManager {
+ public:
+  typedef EventChannel<DirectoryManagerEvent> Channel;
+
+  // root_path specifies where db is stored.
+  explicit DirectoryManager(const PathString& root_path);
+  ~DirectoryManager();
+
+  static const PathString GetSyncDataDatabaseFilename();
+  const PathString GetSyncDataDatabasePath() const;
+
+  // Opens a directory.  Returns false on error.
+  // Name parameter is the the user's login,
+  // MUST already have been converted to a common case.
+  bool Open(const PathString& name);
+
+  // Marks a directory as closed.  It might take a while until all the
+  // file handles and resources are freed by other threads.
+  void Close(const PathString& name);
+
+  // Marks all directories as closed.  It might take a while until all the
+  // file handles and resources are freed by other threads.
+  void CloseAllDirectories();
+
+  // Should be called at App exit.
+  void FinalSaveChangesForAll();
+
+  // Gets the list of currently open directory names.
+  typedef std::vector<PathString> DirNames;
+  void GetOpenDirectories(DirNames* result);
+
+  Channel* channel() const { return channel_; }
+
+ protected:
+  DirOpenResult OpenImpl(const PathString& name, const PathString& path,
+                         bool* was_open);
+
+  // Helpers for friend class ScopedDirLookup:
+  friend class ScopedDirLookup;
+
+  const PathString root_path_;
+  // protects managed_directory_
+  mutable pthread_mutex_t mutex_;
+  Directory* managed_directory_;
+
+  Channel* const channel_;
+
+ private:
+
+  DISALLOW_COPY_AND_ASSIGN(DirectoryManager);
+};
+
+
+class ScopedDirLookup {
+ public:
+  ScopedDirLookup(DirectoryManager* dirman, const PathString& name);
+  ~ScopedDirLookup();
+
+  inline bool good() {
+    good_checked_ = true;
+    return good_;
+  }
+  Directory* operator -> () const;
+  operator Directory* () const;
+
+ protected:  // Don't allow creation on heap, except by sync API wrapper.
+  friend class sync_api::BaseTransaction;
+  void* operator new(size_t size) { return (::operator new)(size); }
+
+  Directory* dir_;
+  bool good_;
+  // Ensure that the programmer checks good before using the ScopedDirLookup
+  // This member should can be removed if it ever shows up in profiling
+  bool good_checked_;
+  DirectoryManager* const dirman_;
+};
+
+}  // namespace syncable
+
+#endif  // CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_MANAGER_H_