dope_core/backend/uring/platform/
gso.rs

1use crate::io::socket::msg::MsgHdr;
2use std::ptr;
3
4pub const MAX_GSO_SEGMENTS: usize = 64;
5pub const MAX_GSO_BYTES: usize = 65535;
6
7#[derive(Default)]
8#[repr(C, align(8))]
9pub struct Gso([u8; 32]);
10
11impl Gso {
12    pub const fn new() -> Self {
13        Self([0; 32])
14    }
15
16    pub fn attach(&mut self, msg: &mut MsgHdr, segment_size: u16) {
17        if segment_size == 0 {
18            return;
19        }
20        const DATA_LEN: u32 = size_of::<u16>() as u32;
21        let (buf, cap) = (self.0.as_mut_ptr(), self.0.len());
22        unsafe {
23            let controllen = libc::CMSG_SPACE(DATA_LEN) as usize;
24            debug_assert!(controllen <= cap);
25            msg.set_control(buf.cast(), controllen);
26            let hdr = libc::CMSG_FIRSTHDR(msg.raw());
27            (*hdr).cmsg_level = libc::SOL_UDP;
28            (*hdr).cmsg_type = libc::UDP_SEGMENT;
29            (*hdr).cmsg_len = libc::CMSG_LEN(DATA_LEN) as _;
30            ptr::copy_nonoverlapping(
31                ptr::addr_of!(segment_size).cast::<u8>(),
32                libc::CMSG_DATA(hdr),
33                DATA_LEN as usize,
34            );
35        }
36    }
37}
dope_core/backend/uring/platform/gso.rs

dope_core/backend/uring/platform/
gso.rs
