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authorValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
committerValentin Popov <valentin@popov.link>2024-01-08 00:21:28 +0300
commit1b6a04ca5504955c571d1c97504fb45ea0befee4 (patch)
tree7579f518b23313e8a9748a88ab6173d5e030b227 /vendor/rustix/src/backend/linux_raw/net/msghdr.rs
parent5ecd8cf2cba827454317368b68571df0d13d7842 (diff)
downloadfparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.tar.xz
fparkan-1b6a04ca5504955c571d1c97504fb45ea0befee4.zip
Initial vendor packages
Signed-off-by: Valentin Popov <valentin@popov.link>
Diffstat (limited to 'vendor/rustix/src/backend/linux_raw/net/msghdr.rs')
-rw-r--r--vendor/rustix/src/backend/linux_raw/net/msghdr.rs146
1 files changed, 146 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/linux_raw/net/msghdr.rs b/vendor/rustix/src/backend/linux_raw/net/msghdr.rs
new file mode 100644
index 0000000..2b88bfb
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+++ b/vendor/rustix/src/backend/linux_raw/net/msghdr.rs
@@ -0,0 +1,146 @@
+//! Utilities for dealing with message headers.
+//!
+//! These take closures rather than returning a `c::msghdr` directly because
+//! the message headers may reference stack-local data.
+
+#![allow(unsafe_code)]
+
+use crate::backend::c;
+use crate::backend::net::write_sockaddr::{encode_sockaddr_v4, encode_sockaddr_v6};
+
+use crate::io::{self, IoSlice, IoSliceMut};
+use crate::net::{RecvAncillaryBuffer, SendAncillaryBuffer, SocketAddrV4, SocketAddrV6};
+use crate::utils::as_ptr;
+
+use core::mem::{size_of, MaybeUninit};
+use core::ptr::null_mut;
+
+fn msg_iov_len(len: usize) -> c::size_t {
+ // This cast cannot overflow.
+ len as c::size_t
+}
+
+pub(crate) fn msg_control_len(len: usize) -> c::size_t {
+ // Same as above.
+ len as c::size_t
+}
+
+/// Create a message header intended to receive a datagram.
+pub(crate) fn with_recv_msghdr<R>(
+ name: &mut MaybeUninit<c::sockaddr_storage>,
+ iov: &mut [IoSliceMut<'_>],
+ control: &mut RecvAncillaryBuffer<'_>,
+ f: impl FnOnce(&mut c::msghdr) -> io::Result<R>,
+) -> io::Result<R> {
+ control.clear();
+
+ let namelen = size_of::<c::sockaddr_storage>() as c::c_int;
+ let mut msghdr = c::msghdr {
+ msg_name: name.as_mut_ptr().cast(),
+ msg_namelen: namelen,
+ msg_iov: iov.as_mut_ptr().cast(),
+ msg_iovlen: msg_iov_len(iov.len()),
+ msg_control: control.as_control_ptr().cast(),
+ msg_controllen: msg_control_len(control.control_len()),
+ msg_flags: 0,
+ };
+
+ let res = f(&mut msghdr);
+
+ // Reset the control length.
+ if res.is_ok() {
+ unsafe {
+ control.set_control_len(msghdr.msg_controllen.try_into().unwrap_or(usize::MAX));
+ }
+ }
+
+ res
+}
+
+/// Create a message header intended to send without an address.
+pub(crate) fn with_noaddr_msghdr<R>(
+ iov: &[IoSlice<'_>],
+ control: &mut SendAncillaryBuffer<'_, '_, '_>,
+ f: impl FnOnce(c::msghdr) -> R,
+) -> R {
+ f(c::msghdr {
+ msg_name: null_mut(),
+ msg_namelen: 0,
+ msg_iov: iov.as_ptr() as _,
+ msg_iovlen: msg_iov_len(iov.len()),
+ msg_control: control.as_control_ptr().cast(),
+ msg_controllen: msg_control_len(control.control_len()),
+ msg_flags: 0,
+ })
+}
+
+/// Create a message header intended to send with an IPv4 address.
+pub(crate) fn with_v4_msghdr<R>(
+ addr: &SocketAddrV4,
+ iov: &[IoSlice<'_>],
+ control: &mut SendAncillaryBuffer<'_, '_, '_>,
+ f: impl FnOnce(c::msghdr) -> R,
+) -> R {
+ let encoded = encode_sockaddr_v4(addr);
+
+ f(c::msghdr {
+ msg_name: as_ptr(&encoded) as _,
+ msg_namelen: size_of::<SocketAddrV4>() as _,
+ msg_iov: iov.as_ptr() as _,
+ msg_iovlen: msg_iov_len(iov.len()),
+ msg_control: control.as_control_ptr().cast(),
+ msg_controllen: msg_control_len(control.control_len()),
+ msg_flags: 0,
+ })
+}
+
+/// Create a message header intended to send with an IPv6 address.
+pub(crate) fn with_v6_msghdr<R>(
+ addr: &SocketAddrV6,
+ iov: &[IoSlice<'_>],
+ control: &mut SendAncillaryBuffer<'_, '_, '_>,
+ f: impl FnOnce(c::msghdr) -> R,
+) -> R {
+ let encoded = encode_sockaddr_v6(addr);
+
+ f(c::msghdr {
+ msg_name: as_ptr(&encoded) as _,
+ msg_namelen: size_of::<SocketAddrV6>() as _,
+ msg_iov: iov.as_ptr() as _,
+ msg_iovlen: msg_iov_len(iov.len()),
+ msg_control: control.as_control_ptr().cast(),
+ msg_controllen: msg_control_len(control.control_len()),
+ msg_flags: 0,
+ })
+}
+
+/// Create a message header intended to send with a Unix address.
+pub(crate) fn with_unix_msghdr<R>(
+ addr: &crate::net::SocketAddrUnix,
+ iov: &[IoSlice<'_>],
+ control: &mut SendAncillaryBuffer<'_, '_, '_>,
+ f: impl FnOnce(c::msghdr) -> R,
+) -> R {
+ f(c::msghdr {
+ msg_name: as_ptr(&addr.unix) as _,
+ msg_namelen: addr.addr_len() as _,
+ msg_iov: iov.as_ptr() as _,
+ msg_iovlen: msg_iov_len(iov.len()),
+ msg_control: control.as_control_ptr().cast(),
+ msg_controllen: msg_control_len(control.control_len()),
+ msg_flags: 0,
+ })
+}
+
+/// Create a zero-initialized message header struct value.
+pub(crate) fn zero_msghdr() -> c::msghdr {
+ c::msghdr {
+ msg_name: null_mut(),
+ msg_namelen: 0,
+ msg_iov: null_mut(),
+ msg_iovlen: 0,
+ msg_control: null_mut(),
+ msg_controllen: 0,
+ msg_flags: 0,
+ }
+}