c - 如何将我的 swift 类转换为像 objective-c 中的 __bridge 这样的 UnsafePointer

Question

我正在尝试实现到 SecureTransport 的快速桥接C 库。我“认为”只要我知道如何在我的 sslReadCallback/sslWriteCallback 实现中从它读取内容，我就可以将任何东西作为连接传递。这是我正在使用的假设。当我查看 SSLConnectionRef 的定义时似乎就是这种情况:

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

所以我只需要将我的类变成UnsafePointer。不幸的是编译器不喜欢我的尝试。谁能给我提示？

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)
    }
}

在 GCDAsyncSocket 中，它是这样做的:

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

和

SubZeroGCDAsyncSocket *asyncSocket = (__bridge SubZeroGCDAsyncSocket *)connection;

..展开。什么是 swift 的等价物？

非常感谢!

Answer 1

答案在这里:

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

所以现在我执行以下操作:

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)
    }
}

然后我像这样打开:

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

用您自己的类型替换 SecureTransportWrapper。