/// <summary>
/// Call to lock box increases lock
/// </summary>
/// <param name="wrappedConnection"></param>
public SQLiteLockBox(LockableSQLiteConnection wrappedConnection)
{
this.m_connection = wrappedConnection;
Monitor.Enter(this.m_connection.m_lockObject);
#if DEBUG
this.m_connection.m_claimedBy = Thread.CurrentThread.ManagedThreadId;
#endif
this.m_connection.m_lockCount++;
this.m_connection.m_availableEvent.Reset();
}
/// <summary>
/// Register connection
/// </summary>
private void RegisterConnection(LockableSQLiteConnection conn)
{
List <LockableSQLiteConnection> connections = this.GetOrRegisterConnections(conn.ConnectionString);
lock (s_lockObject)
{
connections.Add(conn);
this.m_connectionPool.Remove(conn); // Just in-case
// Lock this connection so I know if I can bypass later
Monitor.Enter(conn);
this.m_tracer.TraceVerbose("++ {0} ({1})", conn.DatabasePath, connections.Count);
}
}
/// <summary>
/// Get the specified connection from the pool or create one
/// </summary>
private LockableSQLiteConnection GetOrCreatePooledConnection(ConnectionString dataSource, bool isReadonly)
{
// Pool exists?
var connectionPool = this.GetConnectionPool(dataSource.Name);
// Get the platform
ISQLitePlatform platform = ApplicationServiceContext.Current.GetService <ISQLitePlatform>();
// Try to lock global (make sure another process isn't hogging it)
LockableSQLiteConnection retVal = null;
if (isReadonly) // Readonly we can use any connection we like
{
retVal = connectionPool.GetEntered() ??
connectionPool.GetFree();
if (retVal == null) // Create a connection
{
retVal = new LockableSQLiteConnection(platform, dataSource, SQLiteOpenFlags.ReadOnly | SQLiteOpenFlags.FullMutex);
retVal.Execute("PRAGMA synchronous = 1");
connectionPool.Add(retVal);
//retVal.Wait();
}
else
{
retVal.Wait(); // Wait for connection to become available
}
}
else // We want write
{
retVal = connectionPool.GetWritable(); // Might be writable connection available
if (retVal == null)
{
retVal = new LockableSQLiteConnection(platform, dataSource, SQLiteOpenFlags.ReadWrite | SQLiteOpenFlags.FullMutex | SQLiteOpenFlags.Create);
retVal.Execute("PRAGMA synchronous = 1");
retVal = connectionPool.AddUnique(retVal, o => !o.IsReadonly);
retVal.Wait();
}
else // Wait for the connection to become available
{
retVal.Wait();
}
}
return(retVal);
}
/// <summary>
/// Unregister connection
/// </summary>
private void UnregisterConnection(LockableSQLiteConnection conn)
{
List <LockableSQLiteConnection> connections = this.GetOrRegisterConnections(conn.ConnectionString);
lock (s_lockObject)
{
Monitor.Exit(conn);
connections.Remove(conn);
// Add connection back onto the pool
if (conn.Persistent)
{
this.m_connectionPool.Add(conn);
}
this.m_tracer.TraceVerbose("-- {0} ({1})", conn.DatabasePath, connections.Count);
}
}
/// <summary>
/// Gets or sets the reset event for the particular database
/// </summary>
private ManualResetEventSlim GetOrRegisterResetEvent(LockableSQLiteConnection connection)
{
ManualResetEventSlim retVal = null;
if (!this.m_connections.TryGetValue(connection.ConnectionString.Name, out retVal))
{
retVal = new ManualResetEventSlim(true);
lock (s_lockObject)
if (!this.m_connections.ContainsKey(connection.ConnectionString.Name))
{
this.m_connections.Add(connection.ConnectionString.Name, retVal);
}
else
{
retVal = this.m_connections[connection.ConnectionString.Name];
}
}
return(retVal);
}
/// <summary>
/// Get or create a pooled connection
/// </summary>
private LockableSQLiteConnection GetOrCreatePooledConnection(ConnectionString dataSource, bool isReadonly)
{
// First is there a connection already?
var connections = this.GetOrRegisterConnections(dataSource);
WriteableSQLiteConnection writeConnection = null;
lock (s_lockObject)
{
if (this.m_writeConnections.TryGetValue(dataSource.Name, out writeConnection))
{
if (Monitor.IsEntered(writeConnection))
{
return(writeConnection);
}
}
var conn = connections.FirstOrDefault(o => Monitor.IsEntered(o));
if (conn != null)
{
return(conn);
}
}
ISQLitePlatform platform = ApplicationContext.Current.GetService <ISQLitePlatform>();
lock (s_lockObject)
{
LockableSQLiteConnection retVal = null;
if (isReadonly)
{
retVal = this.m_connectionPool.OfType <ReadonlySQLiteConnection>().FirstOrDefault(o => o.ConnectionString.Name == dataSource.Name);
}
else
{
if (!this.m_writeConnections.TryGetValue(dataSource.Name, out writeConnection)) // Writeable connection can only have one in the pool so if it isn't there make sure it isn't in the current
{
writeConnection = new WriteableSQLiteConnection(platform, dataSource, SQLiteOpenFlags.ReadWrite | SQLiteOpenFlags.FullMutex | SQLiteOpenFlags.Create)
{
Persistent = true
};
writeConnection.Execute("PRAGMA synchronous = 1");
//writeConnection.Execute("PRAGMA automatic_index = true");
//writeConnection.Execute("PRAGMA journal_mode = WAL");
this.m_writeConnections.Add(dataSource.Name, writeConnection);
}
retVal = writeConnection;
}
// Remove return value
if (retVal != null)
{
this.m_connectionPool.Remove(retVal);
}
else if (isReadonly)
{
retVal = new ReadonlySQLiteConnection(platform, dataSource, SQLiteOpenFlags.ReadOnly | SQLiteOpenFlags.FullMutex)
{
Persistent = true
};
//retVal.Execute("PRAGMA threads = 2");
}
else
{
throw new InvalidOperationException("Should not be here");
}
return(retVal);
}
}
