Merge #572

572: GAT-based Device trait. r=Dirbaio a=Dirbaio

The current `'a` lifetime in the `Device` trait is essentially a workaround for lack of GATs.
I'm just experimenting how this would look like, it'll have to wait until GATs are stable to go in.

The main benefit is structs implementing `Device` can now borrow stuff. This wasn't possible
before because the `for<'d> T: Device<'d>` bounds would essentially imply `T: 'static`.

Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>

.github/workflows/test.yml

@@ -20,8 +20,8 @@ jobs:
         # Test on stable, MSRV, and nightly.
         # Failure is permitted on nightly.
         rust:
-          - stable
-          - 1.61.0
+          #- stable  # TODO: enable again when "stable" is 1.66 or higher.
+          - 1.65.0
           - nightly
 
         features:
@@ -64,8 +64,8 @@ jobs:
         # Test on stable, MSRV, and nightly.
         # Failure is permitted on nightly.
         rust:
-          - stable
-          - 1.61.0
+          #- stable  # TODO: enable again when "stable" is 1.66 or higher.
+          - 1.65.0
           - nightly
 
         features:

CHANGELOG.md

@@ -11,7 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Remove IpAddress::Unspecified
 - When sending packets with a raw socket, the source IP address is sent unmodified (it was previously replaced with the interface's address if it was unspecified).
 - Fix enable `defmt/alloc` if `alloc` or `std` is enabled.
-- Minimum Supported Rust Version (MSRV) **bumped** from 1.56 to 1.60
+- Minimum Supported Rust Version (MSRV) **bumped** from 1.56 to 1.65
 
 ## [0.8.1] - 2022-05-12
 

Cargo.toml

@@ -2,7 +2,7 @@
 name = "smoltcp"
 version = "0.8.1"
 edition = "2018"
-rust-version = "1.61"
+rust-version = "1.65"
 authors = ["whitequark <whitequark@whitequark.org>"]
 description = "A TCP/IP stack designed for bare-metal, real-time systems without a heap."
 documentation = "https://docs.rs/smoltcp/"

README.md

@@ -11,7 +11,7 @@ include complicated compile-time computations, such as macro or type tricks, eve
 at cost of performance degradation.
 
 _smoltcp_ does not need heap allocation *at all*, is [extensively documented][docs],
-and compiles on stable Rust 1.61 and later.
+and compiles on stable Rust 1.65 and later.
 
 _smoltcp_ achieves [~Gbps of throughput](#examplesbenchmarkrs) when tested against
 the Linux TCP stack in loopback mode.

examples/utils.rs

@@ -84,11 +84,7 @@ pub fn parse_options(options: &Options, free: Vec<&str>) -> Matches {
                     free.join(" ")
                 );
                 print!("{}", options.usage(&brief));
-                process::exit(if matches.free.len() != free.len() {
-                    1
-                } else {
-                    0
-                })
+                process::exit((matches.free.len() != free.len()) as _);
             }
             matches
         }
@@ -159,7 +155,7 @@ pub fn parse_middleware_options<D>(
     loopback: bool,
 ) -> FaultInjector<Tracer<PcapWriter<D, Box<dyn io::Write>>>>
 where
-    D: for<'a> Device<'a>,
+    D: Device,
 {
     let drop_chance = matches
         .opt_str("drop-chance")

fuzz/utils.rs

@@ -93,7 +93,7 @@ pub fn parse_middleware_options<D>(
     loopback: bool,
 ) -> FaultInjector<Tracer<PcapWriter<D, Box<dyn Write>>>>
 where
-    D: for<'a> Device<'a>,
+    D: Device,
 {
     let drop_chance = matches
         .opt_str("drop-chance")

src/iface/fragmentation.rs

@@ -364,7 +364,7 @@ impl<'a, K: Eq + Ord + Clone + Copy> PacketAssemblerSet<'a, K> {
     /// - Returns [`Error::PacketAssemblerSetKeyNotFound`] when the key was not found in the set.
     pub(crate) fn get_packet_assembler_mut(&mut self, key: &K) -> Result<&mut PacketAssembler<'a>> {
         if let Some(i) = self.index_buffer.get(key) {
-            Ok(&mut self.packet_buffer[*i as usize])
+            Ok(&mut self.packet_buffer[*i])
         } else {
             Err(Error::PacketAssemblerSetKeyNotFound)
         }
@@ -379,7 +379,7 @@ impl<'a, K: Eq + Ord + Clone + Copy> PacketAssemblerSet<'a, K> {
     /// - Returns [`Error::PacketAssemblerIncomplete`] when the fragments assembler was empty or not fully assembled.
     pub(crate) fn get_assembled_packet(&mut self, key: &K) -> Result<&[u8]> {
         if let Some(i) = self.index_buffer.get(key) {
-            let p = self.packet_buffer[*i as usize].assemble()?;
+            let p = self.packet_buffer[*i].assemble()?;
             self.index_buffer.remove(key);
             Ok(p)
         } else {
@@ -392,10 +392,7 @@ impl<'a, K: Eq + Ord + Clone + Copy> PacketAssemblerSet<'a, K> {
         loop {
             let mut key = None;
             for (k, i) in self.index_buffer.iter() {
-                if matches!(
-                    self.packet_buffer[*i as usize].assembler,
-                    AssemblerState::NotInit
-                ) {
+                if matches!(self.packet_buffer[*i].assembler, AssemblerState::NotInit) {
                     key = Some(*k);
                     break;
                 }
@@ -416,7 +413,7 @@ impl<'a, K: Eq + Ord + Clone + Copy> PacketAssemblerSet<'a, K> {
         F: Fn(&mut PacketAssembler<'_>) -> Result<bool>,
     {
         for (_, i) in &mut self.index_buffer.iter() {
-            let frag = &mut self.packet_buffer[*i as usize];
+            let frag = &mut self.packet_buffer[*i];
             if f(frag)? {
                 frag.mark_discarded();
             }

src/iface/interface/ipv4.rs

@@ -507,7 +507,7 @@ impl<'a> InterfaceInner<'a> {
             }
 
             tx_buffer[repr.buffer_len()..][..payload_len].copy_from_slice(
-                &buffer[*frag_offset as usize + repr.buffer_len() as usize..][..payload_len],
+                &buffer[*frag_offset as usize + repr.buffer_len()..][..payload_len],
             );
 
             // Update the frag offset for the next fragment.

src/iface/interface/mod.rs

@@ -563,7 +563,7 @@ let iface = builder.finalize(&mut device);
     /// [neighbor_cache]: #method.neighbor_cache
     pub fn finalize<D>(self, device: &mut D) -> Interface<'a>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         let caps = device.capabilities();
 
@@ -905,7 +905,7 @@ impl<'a> Interface<'a> {
         timestamp: Instant,
     ) -> Result<bool>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         self.inner.now = timestamp;
 
@@ -947,7 +947,7 @@ impl<'a> Interface<'a> {
         timestamp: Instant,
     ) -> Result<bool>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         self.inner.now = timestamp;
 
@@ -1047,7 +1047,7 @@ impl<'a> Interface<'a> {
         sockets: &mut SocketSet<'_>,
     ) -> Result<bool>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         self.inner.now = timestamp;
 
@@ -1152,7 +1152,7 @@ impl<'a> Interface<'a> {
 
     fn socket_ingress<D>(&mut self, device: &mut D, sockets: &mut SocketSet<'_>) -> bool
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         let mut processed_any = false;
         let Self {
@@ -1208,7 +1208,7 @@ impl<'a> Interface<'a> {
 
     fn socket_egress<D>(&mut self, device: &mut D, sockets: &mut SocketSet<'_>) -> bool
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         let Self {
             inner,
@@ -1318,7 +1318,7 @@ impl<'a> Interface<'a> {
     #[cfg(feature = "proto-igmp")]
     fn igmp_egress<D>(&mut self, device: &mut D) -> Result<bool>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         match self.inner.igmp_report_state {
             IgmpReportState::ToSpecificQuery {
@@ -1384,7 +1384,7 @@ impl<'a> Interface<'a> {
     #[cfg(feature = "proto-ipv4-fragmentation")]
     fn ipv4_egress<D>(&mut self, device: &mut D) -> Result<bool>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         // Reset the buffer when we transmitted everything.
         if self.out_packets.ipv4_out_packet.finished() {
@@ -1422,7 +1422,7 @@ impl<'a> Interface<'a> {
     #[cfg(feature = "proto-sixlowpan-fragmentation")]
     fn sixlowpan_egress<D>(&mut self, device: &mut D) -> Result<bool>
     where
-        D: for<'d> Device<'d> + ?Sized,
+        D: Device + ?Sized,
     {
         // Reset the buffer when we transmitted everything.
         if self.out_packets.sixlowpan_out_packet.finished() {

src/lib.rs

@@ -65,7 +65,7 @@
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!
-//! This crate is guaranteed to compile on stable Rust 1.61 and up with any valid set of features.
+//! This crate is guaranteed to compile on stable Rust 1.65 and up with any valid set of features.
 //! It *might* compile on older versions but that may change in any new patch release.
 //!
 //! The exception is when using the `defmt` feature, in which case `defmt`'s MSRV applies, which

src/phy/fault_injector.rs

@@ -94,13 +94,13 @@ impl State {
 /// adverse network conditions (such as random packet loss or corruption), or software
 /// or hardware limitations (such as a limited number or size of usable network buffers).
 #[derive(Debug)]
-pub struct FaultInjector<D: for<'a> Device<'a>> {
+pub struct FaultInjector<D: Device> {
     inner: D,
     state: RefCell<State>,
     config: Config,
 }
 
-impl<D: for<'a> Device<'a>> FaultInjector<D> {
+impl<D: Device> FaultInjector<D> {
     /// Create a fault injector device, using the given random number generator seed.
     pub fn new(inner: D, seed: u32) -> FaultInjector<D> {
         let state = State {
@@ -195,12 +195,13 @@ impl<D: for<'a> Device<'a>> FaultInjector<D> {
     }
 }
 
-impl<'a, D> Device<'a> for FaultInjector<D>
-where
-    D: for<'b> Device<'b>,
-{
-    type RxToken = RxToken<'a, <D as Device<'a>>::RxToken>;
-    type TxToken = TxToken<'a, <D as Device<'a>>::TxToken>;
+impl<D: Device> Device for FaultInjector<D> {
+    type RxToken<'a> = RxToken<'a, D::RxToken<'a>>
+    where
+        Self: 'a;
+    type TxToken<'a> = TxToken<'a, D::TxToken<'a>>
+    where
+        Self: 'a;
 
     fn capabilities(&self) -> DeviceCapabilities {
         let mut caps = self.inner.capabilities();
@@ -210,7 +211,7 @@ where
         caps
     }
 
-    fn receive(&'a mut self) -> Option<(Self::RxToken, Self::TxToken)> {
+    fn receive(&mut self) -> Option<(Self::RxToken<'_>, Self::TxToken<'_>)> {
         let &mut Self {
             ref mut inner,
             ref state,
@@ -233,7 +234,7 @@ where
         })
     }
 
-    fn transmit(&'a mut self) -> Option<Self::TxToken> {
+    fn transmit(&mut self) -> Option<Self::TxToken<'_>> {
         let &mut Self {
             ref mut inner,
             ref state,

src/phy/fuzz_injector.rs

@@ -19,14 +19,14 @@ pub trait Fuzzer {
 #[allow(unused)]
 #[derive(Debug)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]
-pub struct FuzzInjector<D: for<'a> Device<'a>, FTx: Fuzzer, FRx: Fuzzer> {
+pub struct FuzzInjector<D: Device, FTx: Fuzzer, FRx: Fuzzer> {
     inner: D,
     fuzz_tx: FTx,
     fuzz_rx: FRx,
 }
 
 #[allow(unused)]
-impl<D: for<'a> Device<'a>, FTx: Fuzzer, FRx: Fuzzer> FuzzInjector<D, FTx, FRx> {
+impl<D: Device, FTx: Fuzzer, FRx: Fuzzer> FuzzInjector<D, FTx, FRx> {
     /// Create a fuzz injector device.
     pub fn new(inner: D, fuzz_tx: FTx, fuzz_rx: FRx) -> FuzzInjector<D, FTx, FRx> {
         FuzzInjector {
@@ -42,14 +42,17 @@ impl<D: for<'a> Device<'a>, FTx: Fuzzer, FRx: Fuzzer> FuzzInjector<D, FTx, FRx>
     }
 }
 
-impl<'a, D, FTx, FRx> Device<'a> for FuzzInjector<D, FTx, FRx>
+impl<D: Device, FTx, FRx> Device for FuzzInjector<D, FTx, FRx>
 where
-    D: for<'b> Device<'b>,
-    FTx: Fuzzer + 'a,
-    FRx: Fuzzer + 'a,
+    FTx: Fuzzer,
+    FRx: Fuzzer,
 {
-    type RxToken = RxToken<'a, <D as Device<'a>>::RxToken, FRx>;
-    type TxToken = TxToken<'a, <D as Device<'a>>::TxToken, FTx>;
+    type RxToken<'a> = RxToken<'a, D::RxToken<'a>, FRx>
+    where
+        Self: 'a;
+    type TxToken<'a> = TxToken<'a, D::TxToken<'a>, FTx>
+    where
+        Self: 'a;
 
     fn capabilities(&self) -> DeviceCapabilities {
         let mut caps = self.inner.capabilities();
@@ -59,7 +62,7 @@ where
         caps
     }
 
-    fn receive(&'a mut self) -> Option<(Self::RxToken, Self::TxToken)> {
+    fn receive(&mut self) -> Option<(Self::RxToken<'_>, Self::TxToken<'_>)> {
         let &mut Self {
             ref mut inner,
             ref fuzz_rx,
@@ -78,7 +81,7 @@ where
         })
     }
 
-    fn transmit(&'a mut self) -> Option<Self::TxToken> {
+    fn transmit(&mut self) -> Option<Self::TxToken<'_>> {
         let &mut Self {
             ref mut inner,
             fuzz_rx: _,

src/phy/loopback.rs

@@ -29,9 +29,9 @@ impl Loopback {
     }
 }
 
-impl<'a> Device<'a> for Loopback {
-    type RxToken = RxToken;
-    type TxToken = TxToken<'a>;
+impl Device for Loopback {
+    type RxToken<'a> = RxToken;
+    type TxToken<'a> = TxToken<'a>;
 
     fn capabilities(&self) -> DeviceCapabilities {
         DeviceCapabilities {
@@ -41,7 +41,7 @@ impl<'a> Device<'a> for Loopback {
         }
     }
 
-    fn receive(&'a mut self) -> Option<(Self::RxToken, Self::TxToken)> {
+    fn receive(&mut self) -> Option<(Self::RxToken<'_>, Self::TxToken<'_>)> {
         self.queue.pop_front().map(move |buffer| {
             let rx = RxToken { buffer };
             let tx = TxToken {
@@ -51,7 +51,7 @@ impl<'a> Device<'a> for Loopback {
         })
     }
 
-    fn transmit(&'a mut self) -> Option<Self::TxToken> {
+    fn transmit(&mut self) -> Option<Self::TxToken<'_>> {
         Some(TxToken {
             queue: &mut self.queue,
         })