Unable to create UDP and TCP sockets #223

crawford · 2018-05-31T05:47:02Z

I'm trying to create two listening sockets, one UDP and one TCP, with the following code:

    let mut udp_rx_payload = [0; 128];   
    let mut udp_rx_metadata = [PacketMetadata::EMPTY; 1];
    let mut udp_tx_payload = [0; 128];
    let mut udp_tx_metadata = [PacketMetadata::EMPTY; 1];
    let udp_socket = UdpSocket::new(
        UdpSocketBuffer::new(udp_rx_metadata.as_mut(), udp_rx_payload.as_mut()),
        UdpSocketBuffer::new(udp_tx_metadata.as_mut(), udp_tx_payload.as_mut()),
    );                        

    let mut tcp_rx_payload = [0; 128];                      
    let mut tcp_tx_payload = [0; 128];
    let tcp_socket = TcpSocket::new(
        TcpSocketBuffer::new(tcp_rx_payload.as_mut()),                         
        TcpSocketBuffer::new(tcp_tx_payload.as_mut()),
    );
            
    let mut sockets = [None, None];
    let mut socket_set = SocketSet::new(sockets.as_mut());
    let udp_handle = socket_set.add(udp_socket);
    let tcp_handle = socket_set.add(tcp_socket);

When I try to build this, I get the following error:

error[E0597]: `udp_rx_payload` does not live long enough
   --> src/main.rs:117:56
    |
117 |         UdpSocketBuffer::new(udp_rx_metadata.as_mut(), udp_rx_payload.as_mut()),
    |                                                        ^^^^^^^^^^^^^^ borrowed value does not live long enough
...
167 | }
    | - borrowed value only lives until here
    |
    = note: borrowed value must be valid for the static lifetime...

error[E0597]: `udp_tx_payload` does not live long enough
   --> src/main.rs:118:56
    |
118 |         UdpSocketBuffer::new(udp_tx_metadata.as_mut(), udp_tx_payload.as_mut()),
    |                                                        ^^^^^^^^^^^^^^ borrowed value does not live long enough
...
167 | }
    | - borrowed value only lives until here
    |
    = note: borrowed value must be valid for the static lifetime...

If I comment out either of the calls to socket_set.add, it builds and runs.

I'm using rustc 1.28.0-nightly (c2d46037f 2018-05-24).

The text was updated successfully, but these errors were encountered:

whitequark · 2018-05-31T13:21:43Z

The lifetimes of all sockets unify with each other, so you need to group them like this:

    let mut udp_rx_payload = [0; 128];   
    let mut udp_tx_payload = [0; 128];
    let mut tcp_rx_payload = [0; 128];                      
    let mut tcp_tx_payload = [0; 128];
    let mut udp_tx_metadata = [PacketMetadata::EMPTY; 1];
    let mut udp_rx_metadata = [PacketMetadata::EMPTY; 1];
    let udp_socket = UdpSocket::new(
        UdpSocketBuffer::new(udp_rx_metadata.as_mut(), udp_rx_payload.as_mut()),
        UdpSocketBuffer::new(udp_tx_metadata.as_mut(), udp_tx_payload.as_mut()),
    );                        
    let tcp_socket = TcpSocket::new(
        TcpSocketBuffer::new(tcp_rx_payload.as_mut()),                         
        TcpSocketBuffer::new(tcp_tx_payload.as_mut()),
    );
            
    let mut sockets = [None, None];
    let mut socket_set = SocketSet::new(sockets.as_mut());
    let udp_handle = socket_set.add(udp_socket);
    let tcp_handle = socket_set.add(tcp_socket);

cf. #48

crawford · 2018-05-31T15:28:42Z

That gives me the same error as before:

error[E0597]: `udp_rx_payload` does not live long enough
   --> src/main.rs:119:56
    |
119 |         UdpSocketBuffer::new(udp_rx_metadata.as_mut(), udp_rx_payload.as_mut()),
    |                                                        ^^^^^^^^^^^^^^ borrowed value does not live long enough
...
166 | }
    | - borrowed value only lives until here
    |
    = note: borrowed value must be valid for the static lifetime...

error[E0597]: `udp_tx_payload` does not live long enough
   --> src/main.rs:120:56
    |
120 |         UdpSocketBuffer::new(udp_tx_metadata.as_mut(), udp_tx_payload.as_mut()),
    |                                                        ^^^^^^^^^^^^^^ borrowed value does not live long enough
...
166 | }
    | - borrowed value only lives until here
    |
    = note: borrowed value must be valid for the static lifetime...

Is there something in the surrounding code that I need to check? All of this code exists in main.

whitequark · 2018-05-31T17:03:28Z

Oh sorry, I didn't go far enough. You need...

    let mut udp_rx_payload = [0; 128];   
    let mut udp_tx_payload = [0; 128];
    let mut tcp_rx_payload = [0; 128];                      
    let mut tcp_tx_payload = [0; 128];
    let mut udp_tx_metadata = [PacketMetadata::EMPTY; 1];
    let mut udp_rx_metadata = [PacketMetadata::EMPTY; 1];
    let udp_rx_buffer = UdpSocketBuffer::new(udp_rx_metadata.as_mut(), udp_rx_payload.as_mut());
    let udp_tx_buffer = UdpSocketBuffer::new(udp_tx_metadata.as_mut(), udp_tx_payload.as_mut());
    let tcp_rx_buffer = TcpSocketBuffer::new(tcp_rx_metadata.as_mut(), tcp_rx_payload.as_mut());
    let tcp_tx_buffer = TcpSocketBuffer::new(tcp_tx_metadata.as_mut(), tcp_tx_payload.as_mut());
    let udp_socket = UdpSocket::new(udp_rx_buffer, udp_tx_buffer);                        
    let tcp_socket = TcpSocket::new(tcp_rx_buffer, tcp_tx_buffer);
            
    let mut sockets = [None, None];
    let mut socket_set = SocketSet::new(sockets.as_mut());
    let udp_handle = socket_set.add(udp_socket);
    let tcp_handle = socket_set.add(tcp_socket);

crawford · 2018-05-31T18:29:48Z

(There is a small typo above. TcpSocketBuffer::new doesn't need metadata). I still get the same error :(

whitequark · 2018-05-31T18:35:16Z

Can you post your project somewhere? In any case, here's a working example: https://github.com/m-labs/ionpak/blob/master/firmware/src/main.rs#L158-L194.

crawford · 2018-05-31T19:27:35Z

I just made it public. Here is the code in question (without the suggested changes): https://github.com/crawford/PoE/blob/3f26e93afc082af7fc9c40eb1b5c55354afa071a/firmware/src/main.rs#L113.

progval · 2018-06-21T14:46:42Z

@crawford Hmm, I can compile your code with the nightly compiler. (Maybe thanks to the NLL?)

crawford · 2018-07-03T04:54:10Z

@progval Did you uncomment line 131?

crawford · 2018-07-03T05:00:53Z

@whitequark I'm now getting an eerily similar error after refactoring my Device implementation. This code fails with the following error message:

error[E0597]: `tx_buffer` does not live long enough
   --> src/main.rs:111:18
    |
111 |             &mut tx_buffer,
    |                  ^^^^^^^^^ borrowed value does not live long enough
...
178 | }
    | - `tx_buffer` dropped here while still borrowed
    |
    = note: values in a scope are dropped in the opposite order they are created

I wonder if both this failure and the original actually stem from the type definition of Interface and InterfaceBuilder. Both of these structs dictate that DeviceT is a Device of any lifetime (including 'static), but my Device does not implement 'static (unlike the Device in IonPak). I've been trying to modify smoltcp to lift that restriction, but I haven't been able to satisfy the borrow checker yet.

EDIT:

I was able to fix this last error by breaking up the lifetimes. Changing something like this:

struct MAC<'a> {
    rx_buffer: &'a mut RxBuffer<'a>,
    tx_buffer: &'a mut TxBuffer<'a>,
}

into this:

struct MAC<'a, 'b: 'a> {
    rx_buffer: &'a mut RxBuffer<'b>,
    tx_buffer: &'a mut TxBuffer<'b>,
}

birkenfeld · 2018-07-03T05:56:19Z

Does it change anything if you move rx_buffer/tx_buffer above the creation of neighbor_cache and ip_addrs?

crawford · 2018-07-03T14:20:49Z

@birkenfeld Unfortunately, no.

crawford · 2019-08-18T16:51:21Z

This has been fixed by #304.

whitequark added the kind/question label Jun 23, 2018

crawford mentioned this issue Aug 14, 2019

Allow TCPSockets in a SocketSet without 'static storage lifetime #304

Closed

crawford closed this as completed Aug 18, 2019

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Unable to create UDP and TCP sockets #223

Unable to create UDP and TCP sockets #223

crawford commented May 31, 2018

whitequark commented May 31, 2018

crawford commented May 31, 2018

whitequark commented May 31, 2018

crawford commented May 31, 2018

whitequark commented May 31, 2018

crawford commented May 31, 2018 •

edited

progval commented Jun 21, 2018

crawford commented Jul 3, 2018

crawford commented Jul 3, 2018 •

edited

birkenfeld commented Jul 3, 2018

crawford commented Jul 3, 2018

crawford commented Aug 18, 2019

Unable to create UDP and TCP sockets #223

Unable to create UDP and TCP sockets #223

Comments

crawford commented May 31, 2018

whitequark commented May 31, 2018

crawford commented May 31, 2018

whitequark commented May 31, 2018

crawford commented May 31, 2018

whitequark commented May 31, 2018

crawford commented May 31, 2018 • edited

progval commented Jun 21, 2018

crawford commented Jul 3, 2018

crawford commented Jul 3, 2018 • edited

birkenfeld commented Jul 3, 2018

crawford commented Jul 3, 2018

crawford commented Aug 18, 2019

crawford commented May 31, 2018 •

edited

crawford commented Jul 3, 2018 •

edited