public bool Start() { lock (lockObject) { treeSystem = new StoreTreeSystem(store, branchNodeSize, leafNodeSize, heapNodeCacheSize, branchNodeCacheSize); treeSystem.Create(); treeSystem.CheckPoint(); // The actual database StoreTreeSystem treeStore; // Get the header area IArea headerArea = store.GetArea(-1); int magicValue = headerArea.ReadInt4(); // If header area magic value is zero, then we assume this is a brand // new database and initialize it with the configuration information // given. if (magicValue == 0) { // Create a tree store inside the file store, treeStore = new StoreTreeSystem(store, branchNodeSize, leafNodeSize, heapNodeCacheSize, branchNodeCacheSize); // Create the tree and returns a pointer to the tree, long treePointer = treeStore.Create(); // Create an area object with state information about the tree IAreaWriter awriter = store.CreateArea(128); awriter.WriteInt4(0x0101); // The version value awriter.WriteInt8(treePointer); awriter.WriteInt4(branchNodeSize); awriter.WriteInt4(leafNodeSize); awriter.Finish(); long dummy = awriter.Id; IMutableArea harea = store.GetMutableArea(-1); harea.WriteInt4(0x092BA001); // The magic value harea.WriteInt8(awriter.Id); harea.CheckOut(); } else if (magicValue == 0x092BA001) { long apointer = headerArea.ReadInt8(); // The area that contains configuration details, IArea initArea = store.GetArea(apointer); int version = initArea.ReadInt4(); if (version != 0x0101) { throw new IOException("Unknown version in tree initialization area"); } // Read the pointer to the tree store long treePointer = initArea.ReadInt8(); // Read the branch and leaf node sizes as set when the database was // created. int ibranchNodeSize = initArea.ReadInt4(); int ileafNodeSize = initArea.ReadInt4(); // Create the tree store treeStore = new StoreTreeSystem(store, ibranchNodeSize, ileafNodeSize, heapNodeCacheSize, branchNodeCacheSize); // Initialize the tree treeStore.Init(treePointer); } else { throw new IOException("Data is corrupt, invalid magic value in store"); } // Set the point of the tree store treeStore.CheckPoint(); // Set up final internal state and return true treeSystem = treeStore; databaseStarted = true; return(true); } }
public bool Start() { lock (lockObject) { // We can't start a database that is already started, if (databaseStarted || treeSystem != null) { return(false); } // Make a data.koi file with a single TreeSystem structure mapped into it const string fileExt = "cdb"; const string dbFileName = "data"; bufferManager = new LoggingBufferManager(path, path, false, maxPageCount, pageSize, fileExt, fileRolloverSize, logger, true); bufferManager.Start(); // The backing store fileStore = new JournalledFileStore(dbFileName, bufferManager, false); fileStore.Open(); // The actual database StoreTreeSystem treeStore; // Get the header area IArea headerArea = fileStore.GetArea(-1); int magicValue = headerArea.ReadInt4(); // If header area magic value is zero, then we assume this is a brand // new database and initialize it with the configuration information // given. if (magicValue == 0) { // Create a tree store inside the file store, treeStore = new StoreTreeSystem(fileStore, branchNodeSize, leafNodeSize, heapNodeCacheSize, branchNodeCacheSize); // Create the tree and returns a pointer to the tree, long treePointer = treeStore.Create(); // Create an area object with state information about the tree IAreaWriter awriter = fileStore.CreateArea(128); awriter.WriteInt4(0x0101); // The version value awriter.WriteInt8(treePointer); awriter.WriteInt4(branchNodeSize); awriter.WriteInt4(leafNodeSize); awriter.Finish(); long dummy = awriter.Id; IMutableArea harea = fileStore.GetMutableArea(-1); harea.WriteInt4(0x092BA001); // The magic value harea.WriteInt8(awriter.Id); harea.CheckOut(); } else if (magicValue == 0x092BA001) { long apointer = headerArea.ReadInt8(); // The area that contains configuration details, IArea initArea = fileStore.GetArea(apointer); int version = initArea.ReadInt4(); if (version != 0x0101) { throw new IOException("Unknown version in tree initialization area"); } // Read the pointer to the tree store long treePointer = initArea.ReadInt8(); // Read the branch and leaf node sizes as set when the database was // created. int ibranchNodeSize = initArea.ReadInt4(); int ileafNodeSize = initArea.ReadInt4(); // Create the tree store treeStore = new StoreTreeSystem(fileStore, ibranchNodeSize, ileafNodeSize, heapNodeCacheSize, branchNodeCacheSize); // Initialize the tree treeStore.Init(treePointer); } else { throw new IOException("Data is corrupt, invalid magic value in store"); } // Set the point of the tree store treeStore.CheckPoint(); // Set up final internal state and return true treeSystem = treeStore; databaseStarted = true; return(true); } }