State *statePtr = (State *) instanceData;

    if (mode == TCL_MODE_NONBLOCKING) {
	statePtr->flags |= TLS_TCL_ASYNC;
    } else {
	statePtr->flags &= ~(TLS_TCL_ASYNC);
    }
    return(0);
}

/*
 *-------------------------------------------------------------------
 *
 * TlsCloseProc --
 *

static int TlsCloseProc(ClientData instanceData, Tcl_Interp *interp) {
    State *statePtr = (State *) instanceData;

    dprintf("TlsCloseProc(%p)", (void *) statePtr);

    Tls_Clean(statePtr);
    Tcl_EventuallyFree((ClientData)statePtr, Tls_Free);
    return(0);
}

static int TlsClose2Proc(ClientData instanceData,    /* The socket state. */
    Tcl_Interp *interp,		/* For errors - can be NULL. */
    int flags)			/* Flags to close read and/or write side of channel */
{
    State *statePtr = (State *) instanceData;

    *errorCodePtr = 0;

    dprintf("WaitForConnect(%p)", (void *) statePtr);
    dprintFlags(statePtr);

    if (!(statePtr->flags & TLS_TCL_INIT)) {
	dprintf("Tls_WaitForConnect called on already initialized channel -- returning with immediate success");
	return(0);
    }

    if (statePtr->flags & TLS_TCL_HANDSHAKE_FAILED) {
	/*
	 * Different types of operations have different requirements
	 * SSL being established
	 */
	if (handshakeFailureIsPermanent) {
	    dprintf("Asked to wait for a TLS handshake that has already failed.  Returning fatal error");
	    *errorCodePtr = ECONNABORTED;
	} else {
	    dprintf("Asked to wait for a TLS handshake that has already failed.  Returning soft error");
	    *errorCodePtr = ECONNRESET;
	}
	Tls_Error(statePtr, "Wait for failed handshake");
	return(-1);
    }

    for (;;) {
	ERR_clear_error();

	/* Not initialized yet! Also calls SSL_do_handshake. */
	if (statePtr->flags & TLS_TCL_SERVER) {

	if (bioShouldRetry) {
	    dprintf("The I/O did not complete -- but we should try it again");

	    if (statePtr->flags & TLS_TCL_ASYNC) {
		dprintf("Returning EAGAIN so that it can be retried later");
		*errorCodePtr = EAGAIN;
		Tls_Error(statePtr, "Handshake not complete, will retry later");
		return(-1);
	    } else {
		dprintf("Doing so now");
		continue;
	    }
	}

	dprintf("We have either completely established the session or completely failed it -- there is no more need to ever retry it though");

	    break;

	case SSL_ERROR_ZERO_RETURN:
	    /* The TLS/SSL peer has closed the connection for writing by sending the close_notify alert */
	    dprintf("SSL_ERROR_ZERO_RETURN: Connect returned an invalid value...");
	    *errorCodePtr = EINVAL;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    return(-1);

	case SSL_ERROR_SYSCALL:
	    /* Some non-recoverable, fatal I/O error occurred */
	    dprintf("SSL_ERROR_SYSCALL");

	    if (backingError == 0 && err == 0) {
		dprintf("EOF reached")

		if (*errorCodePtr == ECONNRESET) {
		    *errorCodePtr = ECONNABORTED;
		}
		Tls_Error(statePtr, (char *) ERR_reason_error_string(backingError));
	    }

	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    return(-1);

	case SSL_ERROR_SSL:
	    /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */
	    dprintf("SSL_ERROR_SSL: Got permanent fatal SSL error, aborting immediately");
	    if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, (char *) X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    }
	    if (backingError != 0) {
		Tls_Error(statePtr, (char *) ERR_reason_error_string(backingError));
	    }
	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    *errorCodePtr = ECONNABORTED;
	    return(-1);

	case SSL_ERROR_WANT_READ:
	case SSL_ERROR_WANT_WRITE:
	case SSL_ERROR_WANT_X509_LOOKUP:
	case SSL_ERROR_WANT_CONNECT:
	case SSL_ERROR_WANT_ACCEPT:
	case SSL_ERROR_WANT_ASYNC:
	case SSL_ERROR_WANT_ASYNC_JOB:
	case SSL_ERROR_WANT_CLIENT_HELLO_CB:
	default:
	    /* The operation did not complete and should be retried later. */
	    dprintf("Operation did not complete, call function again later: %i", rc);
	    *errorCodePtr = EAGAIN;
	    dprintf("ERR(%d, %d) ", rc, *errorCodePtr);
	    Tls_Error(statePtr, "Operation did not complete, call function again later");
	    return(-1);
    }

    dprintf("Removing the \"TLS_TCL_INIT\" flag since we have completed the handshake");
    statePtr->flags &= ~TLS_TCL_INIT;

    dprintf("Returning in success");
    *errorCodePtr = 0;
    return(0);
}

/*
 *-------------------------------------------------------------------
 *
 * TlsInputProc --
 *

    *errorCodePtr = 0;

    dprintf("BIO_read(%d)", bufSize);

    if (statePtr->flags & TLS_TCL_CALLBACK) {
	/* don't process any bytes while verify callback is running */
	dprintf("Callback is running, reading 0 bytes");
	return(0);
    }

    dprintf("Calling Tls_WaitForConnect");
    tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 0);
    if (tlsConnect < 0) {
	dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr);
	Tls_Error(statePtr, strerror(*errorCodePtr));

	bytesRead = -1;
	if (*errorCodePtr == ECONNRESET) {
	    dprintf("Got connection reset");
	    /* Soft EOF */
	    *errorCodePtr = 0;
	    bytesRead = 0;
	}
	return(bytesRead);
    }

    /*
     * We need to clear the SSL error stack now because we sometimes reach
     * this function with leftover errors in the stack.  If BIO_read
     * returns -1 and intends EAGAIN, there is a leftover error, it will be
     * misconstrued as an error, not EAGAIN.

	    *errorCodePtr = 0;
	    bytesRead = 0;
	    Tls_Error(statePtr, "Unknown error");
	    break;
    }

    dprintf("Input(%d) -> %d [%d]", bufSize, bytesRead, *errorCodePtr);
    return(bytesRead);
}

/*
 *-------------------------------------------------------------------
 *
 * TlsOutputProc --
 *

    dprintf("BIO_write(%p, %d)", (void *) statePtr, toWrite);
    dprintBuffer(buf, toWrite);

    if (statePtr->flags & TLS_TCL_CALLBACK) {
	dprintf("Don't process output while callbacks are running");
	written = -1;
	*errorCodePtr = EAGAIN;
	return(-1);
    }

    dprintf("Calling Tls_WaitForConnect");
    tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 1);
    if (tlsConnect < 0) {
	dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr);
	Tls_Error(statePtr, strerror(*errorCodePtr));

	written = -1;
	if (*errorCodePtr == ECONNRESET) {
	    dprintf("Got connection reset");
	    /* Soft EOF */
	    *errorCodePtr = 0;
	    written = 0;
	}
	return(written);
    }

    if (toWrite == 0) {
	dprintf("zero-write");
	err = BIO_flush(statePtr->bio);

	if (err <= 0) {
	    dprintf("Flushing failed");
	    Tls_Error(statePtr, "Flush failed");

	    *errorCodePtr = EIO;
	    written = 0;
	    return(-1);
	}

	written = 0;
	*errorCodePtr = 0;
	return(0);
    }

    /*
     * We need to clear the SSL error stack now because we sometimes reach
     * this function with leftover errors in the stack.  If BIO_write
     * returns -1 and intends EAGAIN, there is a leftover error, it will be
     * misconstrued as an error, not EAGAIN.

	default:
	    dprintf("unknown error: %d", err);
	    Tls_Error(statePtr, "Unknown error");
	    break;
    }

    dprintf("Output(%d) -> %d", toWrite, written);
    return(written);
}

/*
 *-------------------------------------------------------------------
 *
 * TlsSetOptionProc --
 *

 */
static int TlsGetHandleProc(ClientData instanceData,    /* Socket state. */
    int direction,		/* TCL_READABLE or TCL_WRITABLE */
    ClientData *handlePtr)	/* Handle associated with the channel */
{
    State *statePtr = (State *) instanceData;

    return(Tcl_GetChannelHandle(Tls_GetParent(statePtr, TLS_TCL_FASTPATH), direction, handlePtr));
}

/*
 *-------------------------------------------------------------------
 *
 * TlsNotifyProc --
 *

	}

	dprintf("Tls_WaitForConnect returned an error");
    }

    dprintf("Returning %i", mask);

    return(mask);
}

/*
 *------------------------------------------------------*
 *
 *    TlsChannelHandlerTimer --
 *

}

Tcl_Channel Tls_GetParent(State *statePtr, int maskFlags) {
    dprintf("Requested to get parent of channel %p", statePtr->self);

    if ((statePtr->flags & ~maskFlags) & TLS_TCL_FASTPATH) {
	dprintf("Asked to get the parent channel while we are using FastPath -- returning NULL");
	return(NULL);
    }
    return(Tcl_GetStackedChannel(statePtr->self));
}

/*
 *-------------------------------------------------------------------
 *
 * Tls_ChannelType --
 *