ci: Add workflow to ensure Rust code is consistently formatted

.github/workflows/lint-cargo-fmt.yml

@@ -0,0 +1,36 @@
+# Make sure Rust source code is consistently formatted with rustfmt.
+
+name: "lint-cargo-fmt.yml"
+
+on:
+  pull_request: {}
+
+concurrency:
+  group: "${{ github.workflow }}:${{ github.event.pull_request.number }}"
+  cancel-in-progress: true
+
+jobs:
+  format-check:
+    name: "Check formatting for Rust code"
+    runs-on: "ubuntu-latest"
+    steps:
+      - name: "Install Rust toolchain"
+        uses: "dtolnay/rust-toolchain@stable"
+        with:
+          toolchain: "nightly"
+          components: "rustfmt"
+
+      - name: "Checkout"
+        uses: "actions/checkout@v4"
+        with:
+          fetch-depth: "1"
+          persist-credentials: "false"
+
+      - name: "Check formatting"
+        run: |
+          cargo fmt --check
+
+      - name: "How to fix"
+        if: ${{ failure() }}
+        run: |
+          echo "::notice::Try fixing the issue with 'cargo fmt --all', then commit the changes."

dpdk-sys/build.rs

@@ -42,7 +42,6 @@ fn bind(path: &Path, sysroot: &str) {
         .allowlist_item("RTE.*")
         .blocklist_item("__*")
         .clang_macro_fallback()
-
         // Bindgen tests seem to object to the documentation in the following
         // (not the items themselves, just the documentation associated with them)
         // I suspect this is a bug in bindgen, but I'm not sure.
@@ -57,13 +56,11 @@ fn bind(path: &Path, sysroot: &str) {
         .blocklist_function("rte_dev_dma_unmap")
         .blocklist_function("rte_pci_addr_cmp")
         .blocklist_function("rte_pci_addr_parse")
-
         // rustc doesn't like repr(packed) types which contain other repr(packed) types
         .opaque_type("rte_arp_hdr")
         .opaque_type("rte_arp_ipv4")
         .opaque_type("rte_gtp_psc_generic_hdr")
         .opaque_type("rte_l2tpv2_combined_msg_hdr")
-
         .clang_arg(format!("-I{sysroot}/include"))
         .clang_arg("-fretain-comments-from-system-headers")
         .clang_arg("-fparse-all-comments")

dpdk-sys/src/lib.rs

@@ -10,7 +10,7 @@
     deprecated,
     non_snake_case,
     non_camel_case_types,
-    non_upper_case_globals,
+    non_upper_case_globals
 )]
 
 include!(concat!(env!("OUT_DIR"), "/generated.rs"));

dpdk-sysroot-helper/src/lib.rs

@@ -5,7 +5,8 @@ use std::env;
 use std::path::Path;
 
 // from https://stackoverflow.com/questions/73595435/how-to-get-profile-from-cargo-toml-in-build-rs-or-at-runtime
-#[must_use] pub fn get_profile_name() -> String {
+#[must_use]
+pub fn get_profile_name() -> String {
     // The profile name is always the 3rd last part of the path (with 1 based indexing).
     // e.g., /code/core/target/cli/build/my-build-info-9f91ba6f99d7a061/out
     env::var("OUT_DIR")
@@ -16,7 +17,8 @@ use std::path::Path;
         .to_string()
 }
 
-#[must_use] pub fn get_target_name() -> String {
+#[must_use]
+pub fn get_target_name() -> String {
     // The target name is always the 4th last part of the path (with 1 based indexing).
     // e.g., /code/core/target/cli/build/my-build-info-9f91ba6f99d7a061/out
     env::var("OUT_DIR")
@@ -27,15 +29,18 @@ use std::path::Path;
         .to_string()
 }
 
-#[must_use] pub fn get_project_root() -> String {
+#[must_use]
+pub fn get_project_root() -> String {
     env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set")
 }
 
-#[must_use] pub fn get_compile_env() -> String {
+#[must_use]
+pub fn get_compile_env() -> String {
     env::var("COMPILE_ENV").expect("COMPILE_ENV not set")
 }
 
-#[must_use] pub fn get_sysroot() -> String {
+#[must_use]
+pub fn get_sysroot() -> String {
     let compile_env = env::var("COMPILE_ENV").expect("COMPILE_ENV not set");
     let sysroot_env = format!("{compile_env}/sysroot");
     let target = get_target_name();
@@ -50,7 +55,7 @@ use std::path::Path;
         if fallback_sysroot_path.exists() {
             fallback_sysroot
         } else {
-                panic!("sysroot not found at {expected_sysroot} or {fallback_sysroot}")
+            panic!("sysroot not found at {expected_sysroot} or {fallback_sysroot}")
         }
     }
 }

dpdk/src/dev.rs

@@ -54,7 +54,8 @@ impl DevIndex {
     pub const MAX: u16 = RTE_MAX_ETHPORTS as u16;
 
     /// The index of the port represented as a `u16`.
-    #[must_use] pub fn as_u16(&self) -> u16 {
+    #[must_use]
+    pub fn as_u16(&self) -> u16 {
         self.0
     }
 
@@ -179,9 +180,7 @@ impl DevIndex {
             // However, DPDK has a depressing number of sign and bit-width errors in its API, so we
             // need to check for nonsense values to make a properly safe wrapper.
             // Better to panic than malfunction.
-            Eal::fatal_error(format!(
-                "SocketId for port {self} is negative? {socket_id}"
-            ));
+            Eal::fatal_error(format!("SocketId for port {self} is negative? {socket_id}"));
         }
 
         Ok(SocketId(socket_id as c_uint))
@@ -252,12 +251,7 @@ impl DevConfig {
         let nb_tx_queues = self.num_tx_queues + self.num_hairpin_queues;
 
         let ret = unsafe {
-            rte_eth_dev_configure(
-                dev.index().as_u16(),
-                nb_rx_queues,
-                nb_tx_queues,
-                &eth_conf,
-            )
+            rte_eth_dev_configure(dev.index().as_u16(), nb_rx_queues, nb_tx_queues, &eth_conf)
         };
 
         if ret != 0 {
@@ -661,14 +655,16 @@ impl Manager {
 
 impl DevInfo {
     /// Get the port index of the device.
-    #[must_use] pub fn index(&self) -> DevIndex {
+    #[must_use]
+    pub fn index(&self) -> DevIndex {
         self.index
     }
 
     /// Get the device `if_index`.
     ///
     /// This is the Linux interface index of the device.
-    #[must_use] pub fn if_index(&self) -> u32 {
+    #[must_use]
+    pub fn if_index(&self) -> u32 {
         self.inner.if_index
     }
 
@@ -847,7 +843,6 @@ impl Drop for Dev {
     }
 }
 
-
 #[derive(Debug, thiserror::Error)]
 pub enum SocketIdLookupError {
     #[error("Invalid port ID")]

dpdk/src/eal.rs

@@ -2,13 +2,13 @@
 // Copyright Open Network Fabric Authors
 
 //! DPDK Environment Abstraction Layer (EAL)
+use crate::{dev, mem, socket};
+use alloc::ffi::CString;
 use alloc::format;
 use alloc::string::{String, ToString};
-use crate::{dev, mem, socket};
+use alloc::vec::Vec;
 use core::ffi::c_int;
 use core::fmt::{Debug, Display};
-use alloc::ffi::CString;
-use alloc::vec::Vec;
 use dpdk_sys::*;
 use tracing::{error, info};
 

dpdk/src/flow/mod.rs

@@ -876,7 +876,8 @@ pub struct SetFieldAction {
 
 impl SetFlowField {
     /// Converts the `SetFlowField` into a `SetFieldAction`.
-    #[must_use] pub fn to_flow_rule(&self) -> SetFieldAction {
+    #[must_use]
+    pub fn to_flow_rule(&self) -> SetFieldAction {
         let conf = match self {
             SetFlowField::MacDst(mac_addr) => {
                 let mut value = [0u8; 16];

dpdk/src/lib.rs

@@ -28,13 +28,11 @@
 //! This crate uses lints to discourage casual use of `unwrap`, `expect`, and `panic` to help
 //! encourage this practice.
 #![cfg_attr(not(test), no_std)]
-#![warn(
-    clippy::all,
-)]
+#![warn(clippy::all)]
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
 #![allow(private_bounds)]
-extern crate core;
 extern crate alloc;
+extern crate core;
 
 pub mod dev;
 pub mod eal;

dpdk/src/mem.rs

@@ -3,15 +3,15 @@
 
 //! DPDK memory management wrappers.
 
+use crate::socket::SocketId;
 use alloc::format;
 use alloc::string::String;
-use crate::socket::SocketId;
-use dpdk_sys::*;
 use core::cell::UnsafeCell;
 use core::ffi::{c_char, c_int, CStr};
 use core::fmt::{Debug, Display};
 use core::marker::PhantomData;
 use core::ptr::NonNull;
+use dpdk_sys::*;
 use tracing::{debug, error, warn};
 
 use alloc::sync::Arc;
@@ -121,12 +121,14 @@ impl PoolHandle {
     }
 
     /// Get the name of the memory pool.
-    #[must_use] pub fn name(&self) -> &str {
+    #[must_use]
+    pub fn name(&self) -> &str {
         self.config().name()
     }
 
     /// Get the configuration of the memory pool.
-    #[must_use] pub fn config(&self) -> &PoolConfig {
+    #[must_use]
+    pub fn config(&self) -> &PoolConfig {
         &self.0.config
     }
 }
@@ -349,7 +351,7 @@ impl Drop for PoolInner {
 }
 
 /// A DPDK Mbuf (memory buffer)
-/// 
+///
 /// Usually used to hold an ethernet frame.
 #[repr(transparent)]
 pub struct Mbuf {
@@ -396,7 +398,8 @@ impl Mbuf {
     }
 
     /// Get an immutable ref to the raw data of an Mbuf
-    #[must_use] pub fn raw_data(&self) -> &[u8] {
+    #[must_use]
+    pub fn raw_data(&self) -> &[u8] {
         let pkt_data_start = unsafe {
             (self.raw.as_ref().buf_addr as *const u8)
                 .offset(self.raw.as_ref().annon1.annon1.data_off as isize)
@@ -416,7 +419,8 @@ impl Mbuf {
                 .raw
                 .as_mut()
                 .buf_addr
-                .offset(self.raw.as_ref().annon1.annon1.data_off as isize).cast::<u8>();
+                .offset(self.raw.as_ref().annon1.annon1.data_off as isize)
+                .cast::<u8>();
             core::slice::from_raw_parts_mut(
                 data_start,
                 self.raw.as_ref().annon2.annon1.data_len as usize,

dpdk/src/queue/hairpin.rs

@@ -5,10 +5,10 @@
 use super::{rx, tx};
 use crate::dev::{Dev, DevInfo};
 use crate::queue::rx::RxQueue;
-use crate::queue::tx::{TxQueue};
+use crate::queue::tx::TxQueue;
 use dpdk_sys::*;
-use tracing::debug;
 use errno::ErrorCode;
+use tracing::debug;
 
 /// A stopped DPDK hairpin queue.
 #[derive(Debug)]
@@ -59,11 +59,7 @@ impl HairpinQueue {
     ///
     /// This design ensures that the hairpin queue is correctly tracked in the list of queues
     /// associated with the device.
-    pub(crate) fn new(
-        dev: &Dev,
-        rx: RxQueue,
-        tx: TxQueue,
-    ) -> Result<Self, HairpinConfigFailure> {
+    pub(crate) fn new(dev: &Dev, rx: RxQueue, tx: TxQueue) -> Result<Self, HairpinConfigFailure> {
         let peering = HairpinPeering::define(&dev.info, &rx, &tx);
         // configure the rx queue
 
@@ -77,9 +73,9 @@ impl HairpinQueue {
         };
 
         if ret < 0 {
-            return Err(HairpinConfigFailure::CreationFailed(
-                ErrorCode::parse_i32(ret)
-            ));
+            return Err(HairpinConfigFailure::CreationFailed(ErrorCode::parse_i32(
+                ret,
+            )));
         }
         debug!("RX hairpin queue configured");
 
@@ -93,16 +89,17 @@ impl HairpinQueue {
         };
 
         if ret < 0 {
-            return Err(HairpinConfigFailure::CreationFailed(
-                ErrorCode::parse_i32(ret)
-            ));
+            return Err(HairpinConfigFailure::CreationFailed(ErrorCode::parse_i32(
+                ret,
+            )));
         }
         debug!("TX hairpin queue configured");
 
         Ok(HairpinQueue { rx, tx, peering })
     }
 
-    #[must_use] pub fn start(self) -> HairpinQueue {
+    #[must_use]
+    pub fn start(self) -> HairpinQueue {
         let rx = match self.rx.start() {
             Ok(rx) => rx,
             Err(_) => todo!(),
@@ -111,13 +108,18 @@ impl HairpinQueue {
             Ok(tx) => tx,
             Err(_) => todo!(),
         };
-        HairpinQueue { rx, tx, peering: self.peering }
+        HairpinQueue {
+            rx,
+            tx,
+            peering: self.peering,
+        }
     }
 }
 
 impl HairpinQueue {
     /// Stop the hairpin queue.
-    #[must_use] pub fn stop(self) -> HairpinQueue {
+    #[must_use]
+    pub fn stop(self) -> HairpinQueue {
         let rx = match self.rx.stop() {
             Ok(rx) => rx,
             Err(_) => todo!(),

dpdk/src/queue/mod.rs

@@ -2,9 +2,9 @@
 // Copyright Open Network Fabric Authors
 
 //! DPDK queue abstractions.
+pub mod hairpin;
 pub mod rx;
 pub mod tx;
-pub mod hairpin;
 
 /// The possible states of a DPDK queue
 #[derive(Debug)]
@@ -16,4 +16,3 @@ pub enum QueueState {
     /// A started queue
     Started,
 }
-

dpdk/src/queue/rx.rs

@@ -21,7 +21,8 @@ impl RxQueueIndex {
     /// The index of the rx queue represented as a `u16`.
     ///
     /// This function is mostly useful for interfacing with [`dpdk_sys`].
-    #[must_use] pub fn as_u16(&self) -> u16 {
+    #[must_use]
+    pub fn as_u16(&self) -> u16 {
         self.0
     }
 }