Mark all public struct/enum as non_exhaustive

All the public struct/enum in nmstate might add members/type, hence marking
them as non_exhaustive which will prevent API user from in-compatibility
usage.

This allows us to only preserve API compatibility when adding new member to
struct or enum.

Please refer to
https://doc.rust-lang.org/reference/attributes/type_system.html for more
detail.

Signed-off-by: Gris Ge <[email protected]>

Author: cathay4t

src/buffer.rs

@@ -103,6 +103,7 @@ pub const NETLINK_HEADER_LEN: usize = PAYLOAD.start;
 /// Note that in this second example we don't call
 /// [`new_checked()`](struct.NetlinkBuffer.html#method.new_checked) because the length field is
 /// initialized to 0, so `new_checked()` would return an error.
+#[non_exhaustive]
 pub struct NetlinkBuffer<T> {
     pub buffer: T,
 }

src/error.rs

@@ -12,6 +12,7 @@ const PAYLOAD: Rest = 4..;
 const ERROR_HEADER_LEN: usize = PAYLOAD.start;
 
 #[derive(Debug, PartialEq, Eq, Clone)]
+#[non_exhaustive]
 pub struct ErrorBuffer<T> {
     buffer: T,
 }
@@ -77,6 +78,7 @@ impl<T: AsRef<[u8]> + AsMut<[u8]>> ErrorBuffer<T> {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[non_exhaustive]
 pub struct ErrorMessage {
     pub code: i32,
     pub header: Vec<u8>,

src/header.rs

@@ -20,6 +20,7 @@ use crate::{buffer::NETLINK_HEADER_LEN, Emitable, NetlinkBuffer, Parseable};
 /// +----------------+----------------+----------------+----------------+
 /// ```
 #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, Default)]
+#[non_exhaustive]
 pub struct NetlinkHeader {
     /// Length of the netlink packet, including the header and the payload
     pub length: u32,

src/message.rs

@@ -14,6 +14,7 @@ use crate::{
 
 /// Represent a netlink message.
 #[derive(Debug, PartialEq, Eq, Clone)]
+#[non_exhaustive]
 pub struct NetlinkMessage<I> {
     /// Message header (this is common to all the netlink protocols)
     pub header: NetlinkHeader,

src/payload.rs

@@ -16,6 +16,7 @@ pub const NLMSG_OVERRUN: u16 = 4;
 pub const NLMSG_ALIGNTO: u16 = 4;
 
 #[derive(Debug, PartialEq, Eq, Clone)]
+#[non_exhaustive]
 pub enum NetlinkPayload<I> {
     Done,
     Error(ErrorMessage),