如何将我的swift类转换为与objective-c中的__bridge类似的UnsafePointer

Question

I'm trying to implement a swift bridge to the SecureTransport C libraries. I 'think' I can pass in anything as the connection as long as I know how to read stuff from it in my sslReadCallback/sslWriteCallback implementations. This is the assumption I'm working with. This seems to be the case when I view the definition of SSLConnectionRef:

/* Opaque reference to an I/O connection (socket, endpoint, etc.) */
public typealias SSLConnectionRef = UnsafePointer<Void>

So I just need to turn my class into UnsafePointer. Unfortunately the compiler doesn't like my attempts. Can any one give me tips?

func startSSLProcess()
{
    self.sslContext = SSLCreateContext(kCFAllocatorDefault, SSLProtocolSide.ClientSide, SSLConnectionType.StreamType)
    if let sslContext = self.sslContext
    {
        SSLSetIOFuncs(sslContext, sslReadCallback, sslWriteCallback)
        SSLSetConnection(sslContext, UnsafePointer(self)) // <-- error
        SSLSetSessionOption(sslContext, SSLSessionOption.BreakOnClientAuth, true)
        SSLHandshake(sslContext)
    }
}

In GCDAsyncSocket, it does this:

status = SSLSetConnection(sslContext, (__bridge SSLConnectionRef)self);

and

SubZeroGCDAsyncSocket *asyncSocket = (__bridge SubZeroGCDAsyncSocket *)connection;

.. to unwrap. Whats the swift equivalent of this?

Thanks very much!

Answer 1

The answer was here:

How to cast self to UnsafeMutablePointer<Void> type in swift

So now I do the following:

func startSSLProcess()
{
    self.sslContext = SSLCreateContext(kCFAllocatorDefault, SSLProtocolSide.ClientSide, SSLConnectionType.StreamType)
    if let sslContext = self.sslContext
    {
        SSLSetIOFuncs(sslContext, sslReadCallback, sslWriteCallback)
        SSLSetConnection(sslContext, UnsafePointer(Unmanaged.passUnretained(self).toOpaque()))
        SSLSetSessionOption(sslContext, SSLSessionOption.BreakOnClientAuth, true)
        SSLHandshake(sslContext)
    }
}

And I unwrap like this:

    let transportWrapper:SecureTransportWrapper = Unmanaged<SecureTransportWrapper>.fromOpaque(COpaquePointer(connection)).takeUnretainedValue()

Substitute your own type for SecureTransportWrapper.