Add channel get and set functionality

[connorworley]

I wrote this before realizing #8 already adds get functionality, oops. This also adds set functionality.

[cathay4t]

Let's wait #8 been updated and merged.

[connorworley]

@cathay4t that PR seems to be abandoned. Any objection to continuing here?

[cathay4t]

@cathay4t that PR seems to be abandoned. Any objection to continuing here?

Please continue here. Thanks!

[connorworley]

OK, ready for review :)

[cathay4t]

@connorworley The code looks good. Could you include a unit test like https://github.com/rust-netlink/netlink-packet-route/blob/main/src/link/tests/bond.rs or at lease provide a example code?

I tried strace -s 1000 ethtool -l enp86s0, it seems ethtool is using netlink, so it should be easy to capture the netlink package using nlmon suggested at https://github.com/rust-netlink/netlink-packet-route/blob/main/README.md

[cathay4t]

Instead of every function pushing a NLA, could you try builder way like rust-netlink/rtnetlink#57

[xujunjie-cover]

@connorworley hello，I try to set combined like this.

async fn set_channel(iface_name: &str, count: u32) {
    let (connection, mut handle, _) = ethtool::new_connection().unwrap();
    tokio::spawn(connection);

    let mut request = handle.channel().set(iface_name).combined_count(count).execute().await;

    match a.try_next().await {
        Ok(Some(msg)) => {
            println!("{msg:?}");
        }
        Ok(None) => {
            println!("No message");
        }
        Err(e) => {
            eprintln!("Error: {:?}", e);
        }
    }
}

but no msg in stream. It will be blocked.
Did I use the wrong method.
thanks

Perhaps I need to use notify？

[xujunjie-cover]

@connorworley hello，I try to set combined like this.

async fn set_channel(iface_name: &str, count: u32) {
    let (connection, mut handle, _) = ethtool::new_connection().unwrap();
    tokio::spawn(connection);

    let mut request = handle.channel().set(iface_name).combined_count(count).execute().await;

    match a.try_next().await {
        Ok(Some(msg)) => {
            println!("{msg:?}");
        }
        Ok(None) => {
            println!("No message");
        }
        Err(e) => {
            eprintln!("Error: {:?}", e);
        }
    }
}

but no msg in stream. It will be blocked. Did I use the wrong method. thanks

Perhaps I need to use notify？

strace info

mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fb5560cb000
arch_prctl(ARCH_SET_FS, 0x7fb5560cb740) = 0
set_tid_address(0x7fb5560cba10)         = 8210
set_robust_list(0x7fb5560cba20, 24)     = 0
mprotect(0x7fb5562b7000, 12288, PROT_READ) = 0
mprotect(0x7fb5562cb000, 4096, PROT_READ) = 0
mprotect(0x7fb5563a7000, 4096, PROT_READ) = 0
mprotect(0x5629996a9000, 53248, PROT_READ) = 0
mprotect(0x7fb5563e5000, 8192, PROT_READ) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=10240*1024, rlim_max=20480*1024}) = 0
munmap(0x7fb5563ab000, 48603)           = 0
getrandom("\x63\xc8\xfb\x44\xf2\xf7\x7e\x7c", 8, GRND_NONBLOCK) = 8
brk(NULL)                               = 0x562999ba8000
brk(0x562999bc9000)                     = 0x562999bc9000
socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC) = 3
setsockopt(3, SOL_NETLINK, NETLINK_EXT_ACK, [1], 4) = 0
bind(3, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, 12) = 0
getsockname(3, {sa_family=AF_NETLINK, nl_pid=8210, nl_groups=00000000}, [12]) = 0
sendto(3, [{nlmsg_len=32, nlmsg_type=nlctrl, nlmsg_flags=NLM_F_REQUEST|NLM_F_ACK, nlmsg_seq=1, nlmsg_pid=0}, "\x03\x01\x00\x00\x0c\x00\x02\x00\x65\x74\x68\x74\x6f\x6f\x6c\x00"], 32, 0, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, 12) = 32
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[{nlmsg_len=656, nlmsg_type=nlctrl, nlmsg_flags=0, nlmsg_seq=1, nlmsg_pid=8210}, "\x01\x02\x00\x00\x0c\x00\x02\x00\x65\x74\x68\x74\x6f\x6f\x6c\x00\x06\x00\x01\x00\x15\x00\x00\x00\x08\x00\x03\x00\x01\x00\x00\x00"...], iov_len=65536}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 656
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[{nlmsg_len=36, nlmsg_type=NLMSG_ERROR, nlmsg_flags=NLM_F_CAPPED, nlmsg_seq=1, nlmsg_pid=8210}, {error=0, msg={nlmsg_len=32, nlmsg_type=nlctrl, nlmsg_flags=NLM_F_REQUEST|NLM_F_ACK, nlmsg_seq=1, nlmsg_pid=0}}], iov_len=65536}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 36
sendto(3, [{nlmsg_len=44, nlmsg_type=ethtool, nlmsg_flags=NLM_F_REQUEST|NLM_F_ACK, nlmsg_seq=2, nlmsg_pid=0}, "\x12\x01\x00\x00\x10\x00\x01\x80\x09\x00\x02\x00\x65\x74\x68\x30\x00\x00\x00\x00\x08\x00\x09\x00\x32\x00\x00\x00"], 44, 0, {sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, 12) = 44
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[{nlmsg_len=36, nlmsg_type=NLMSG_ERROR, nlmsg_flags=NLM_F_CAPPED, nlmsg_seq=2, nlmsg_pid=8210}, {error=0, msg={nlmsg_len=44, nlmsg_type=ethtool, nlmsg_flags=NLM_F_REQUEST|NLM_F_ACK, nlmsg_seq=2, nlmsg_pid=0}}], iov_len=65536}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 36
close(3)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++

sendto(3, [{nlmsg_len=44, nlmsg_type=ethtool, nlmsg_flags=NLM_F_REQUEST|NLM_F_ACK, nlmsg_seq=2, nlmsg_pid=0},

ethtool/src/handle.rs

Lines 78 to 85 in 96a97a7

	// multiple netlink message in single socket reply.
	// Using NLM_F_ACK will force rust-netlink to parse all till
	// acked at the end.
	NLM_F_DUMP | NLM_F_REQUEST | NLM_F_ACK
	} else {
	NLM_F_REQUEST
	};

no NLM_F_ACK