Support drops column in /proc/net/udp

Cargo.toml

@@ -13,3 +13,6 @@ categories = ["os::unix-apis", "filesystem"]
 license = "MIT OR Apache-2.0"
 edition = "2018"
 rust-version = "1.70"
+
+[workspace.lints.rust]
+unexpected_cfgs = { level = "warn", check-cfg = ['cfg(tarpaulin)'] }

procfs-core/Cargo.toml

@@ -14,14 +14,20 @@ rust-version.workspace = true
 
 [features]
 default = ["chrono"]
-serde1 = ["serde", "bitflags/serde"]
+serde1 = ["serde", "bitflags/serde", "serde_with"]
 
 [dependencies]
 backtrace = { version = "0.3", optional = true }
 bitflags = { version = "2" }
-chrono = { version = "0.4.20", optional = true, features = ["clock"], default-features = false }
+chrono = { version = "0.4.20", optional = true, features = [
+    "clock",
+], default-features = false }
 hex = "0.4"
 serde = { version = "1.0", features = ["derive"], optional = true }
+serde_with = { version = "3.11", optional = true }
+
+[dev-dependencies]
+serde_json = { version = "1.0" }
 
 [package.metadata.docs.rs]
 all-features = true

procfs-core/src/lib.rs

@@ -245,6 +245,7 @@ macro_rules! from_str {
 ///     ticks_per_second: 100,
 ///     page_size: 4096,
 ///     is_little_endian: true,
+///     kernel_version: "6.11.0".parse().unwrap(),
 /// };
 ///
 /// let rss_bytes = stat.rss_bytes().with_system_info(&system_info);
@@ -255,6 +256,7 @@ pub trait SystemInfoInterface {
     fn page_size(&self) -> u64;
     /// Whether the system is little endian (true) or big endian (false).
     fn is_little_endian(&self) -> bool;
+    fn kernel_version(&self) -> ProcResult<KernelVersion>;
 
     #[cfg(feature = "chrono")]
     fn boot_time(&self) -> ProcResult<chrono::DateTime<chrono::Local>> {
@@ -275,6 +277,7 @@ pub struct ExplicitSystemInfo {
     pub ticks_per_second: u64,
     pub page_size: u64,
     pub is_little_endian: bool,
+    pub kernel_version: KernelVersion,
 }
 
 impl SystemInfoInterface for ExplicitSystemInfo {
@@ -293,6 +296,10 @@ impl SystemInfoInterface for ExplicitSystemInfo {
     fn is_little_endian(&self) -> bool {
         self.is_little_endian
     }
+
+    fn kernel_version(&self) -> ProcResult<KernelVersion> {
+        Ok(self.kernel_version)
+    }
 }
 
 /// Values which can provide an output given the [SystemInfo].

procfs-core/src/net.rs

@@ -6,11 +6,10 @@
 //!
 //! This module corresponds to the `/proc/net` directory and contains various information about the
 //! networking layer.
-use crate::ProcResult;
 use crate::{build_internal_error, expect, from_iter, from_str};
-use std::collections::HashMap;
-
+use crate::{KernelVersion, ProcResult};
 use bitflags::bitflags;
+use std::collections::HashMap;
 use std::io::BufRead;
 use std::net::{Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
 use std::{path::PathBuf, str::FromStr};
@@ -152,6 +151,7 @@ pub struct UdpNetEntry {
     pub tx_queue: u32,
     pub uid: u32,
     pub inode: u64,
+    pub drops: u64,
 }
 
 /// An entry in the Unix socket table
@@ -296,6 +296,15 @@ impl super::FromBufReadSI for UdpNetEntries {
             s.next(); // skip timeout
             let inode = expect!(s.next(), "udp::inode");
 
+            let drops = match system_info.kernel_version() {
+                Ok(version) if version >= KernelVersion::new(2, 6, 27) => {
+                    s.next(); // skip ref
+                    s.next(); // skip pointer
+                    expect!(s.next(), "udp::drops")
+                }
+                _ => "0", // Fallback if the kernel version does not support the drops column or the kernel version could not be read
+            };
+
             vec.push(UdpNetEntry {
                 local_address: parse_addressport_str(local_address, system_info.is_little_endian())?,
                 remote_address: parse_addressport_str(rem_address, system_info.is_little_endian())?,
@@ -304,6 +313,7 @@ impl super::FromBufReadSI for UdpNetEntries {
                 state: expect!(UdpState::from_u8(from_str!(u8, state, 16))),
                 uid,
                 inode: from_str!(u64, inode),
+                drops: from_str!(u64, drops),
             });
         }
 
@@ -1728,4 +1738,53 @@ UdpLite: 0 0 0 0 0 0 0 0 0
         let res = Snmp::from_read(r).unwrap();
         println!("{res:?}");
     }
+
+    #[test]
+    fn test_udp_drops_debian_kernel_version_greater_2_6_27() {
+        let expected_drops = 42;
+        let data = format!(
+            r#"   sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
+ 1270: 00000000:0202 00000000:0000 07 00000000:00000000 00:00000000 00000000   104        0 3719665 2 00000000357eb7c3 {expected_drops}"#
+        );
+        let r = std::io::Cursor::new(data.as_bytes());
+        use crate::FromBufReadSI;
+        let entries = UdpNetEntries::from_buf_read(
+            r,
+            &crate::ExplicitSystemInfo {
+                boot_time_secs: 0,
+                ticks_per_second: 0,
+                page_size: 0,
+                is_little_endian: true,
+                kernel_version: "2.6.27".parse().unwrap(),
+            },
+        )
+        .unwrap();
+        let entry = entries.0.first().unwrap();
+
+        assert_eq!(entry.drops, expected_drops)
+    }
+
+    #[test]
+    fn test_udp_drops_debian_kernel_version_smaller_2_6_27() {
+        let data = format!(
+            r#"   sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode
+ 1270: 00000000:0202 00000000:0000 07 00000000:00000000 00:00000000 00000000   104        0 3719665"#
+        );
+        let r = std::io::Cursor::new(data.as_bytes());
+        use crate::FromBufReadSI;
+        let entries = UdpNetEntries::from_buf_read(
+            r,
+            &crate::ExplicitSystemInfo {
+                boot_time_secs: 0,
+                ticks_per_second: 0,
+                page_size: 0,
+                is_little_endian: true,
+                kernel_version: "2.6.26".parse().unwrap(),
+            },
+        )
+        .unwrap();
+        let entry = entries.0.first().unwrap();
+
+        assert_eq!(entry.drops, 0)
+    }
 }

procfs-core/src/sys/kernel/mod.rs

@@ -3,16 +3,20 @@
 //! The files in this directory can be used to tune and monitor miscellaneous
 //! and general things in the operation of the Linux kernel.
 
-use std::cmp;
 use std::collections::HashSet;
 use std::str::FromStr;
+use std::{cmp, fmt::Display};
+
+#[cfg(feature = "serde1")]
+use serde_with::{DeserializeFromStr, SerializeDisplay};
 
 use bitflags::bitflags;
 
 use crate::{ProcError, ProcResult};
 
 /// Represents a kernel version, in major.minor.release version.
-#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash, Default)]
+#[cfg_attr(feature = "serde1", derive(SerializeDisplay, DeserializeFromStr))]
 pub struct Version {
     pub major: u8,
     pub minor: u8,
@@ -99,6 +103,12 @@ impl cmp::PartialOrd for Version {
     }
 }
 
+impl Display for Version {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}.{}.{}", self.major, self.minor, self.patch)
+    }
+}
+
 /// Represents a kernel type
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct Type {
@@ -425,4 +435,33 @@ mod tests {
         let a = SemaphoreLimits::from_str("1 string 500 3200");
         assert!(a.is_err() && a.err().unwrap() == "Failed to parse SEMMNS");
     }
+
+    #[cfg(feature = "serde1")]
+    mod serde_kernel_version {
+        #[test]
+        fn should_serialize_kernel_version() {
+            let version = Version {
+                major: 42,
+                minor: 0,
+                patch: 1,
+            };
+            let version = serde_json::to_string(&version).unwrap();
+
+            // NOTE: The double quote is necessary because of the JSON format.
+            assert_eq!(r#""42.0.1""#, &version);
+        }
+
+        #[test]
+        fn should_deserialize_kernel_version() {
+            let expected = Version {
+                major: 21,
+                minor: 0,
+                patch: 2,
+            };
+            // NOTE: The double quote is necessary because of the JSON format.
+            let version: Version = serde_json::from_str(r#""21.0.2""#).unwrap();
+
+            assert_eq!(version, expected);
+        }
+    }
 }

procfs/Cargo.toml

@@ -39,3 +39,6 @@ rustdoc-args = ["--generate-link-to-definition"]
 [[bench]]
 name = "cpuinfo"
 harness = false
+
+[lints]
+workspace = true

procfs/benches/cpuinfo.rs

@@ -1,10 +1,13 @@
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use procfs::CpuInfo;
+use procfs::Current;
 
 fn bench_cpuinfo(c: &mut Criterion) {
-    c.bench_function("CpuInfo::new", |b| b.iter(|| black_box(CpuInfo::new().unwrap())));
+    c.bench_function("CpuInfo::current", |b| {
+        b.iter(|| black_box(CpuInfo::current().unwrap()))
+    });
 
-    let cpuinfo = black_box(CpuInfo::new().unwrap());
+    let cpuinfo = black_box(CpuInfo::current().unwrap());
     c.bench_function("CpuInfo::get_info", |b| b.iter(|| black_box(cpuinfo.get_info(0))));
     c.bench_function("CpuInfo::model_name", |b| b.iter(|| cpuinfo.model_name(0)));
     c.bench_function("CpuInfo::vendor_id", |b| b.iter(|| cpuinfo.vendor_id(0)));

procfs/examples/lslocks.rs

@@ -5,7 +5,10 @@ use std::path::Path;
 fn main() {
     let myself = Process::myself().unwrap();
     let mountinfo = myself.mountinfo().unwrap();
-    println!("{:18}{:13}{:13}{:13}{:12} Path", "Process", "PID", "Lock Type", "Mode", "Kind");
+    println!(
+        "{:18}{:13}{:13}{:13}{:12} Path",
+        "Process", "PID", "Lock Type", "Mode", "Kind"
+    );
     println!("{}", "=".repeat(74));
     for lock in procfs::locks().unwrap() {
         lock.pid

procfs/examples/mounts.rs

@@ -1,11 +1,11 @@
 // List mountpoints listed in /proc/mounts
 
 fn main() {
-let width = 15;
+    let width = 15;
     for mount_entry in procfs::mounts().unwrap() {
         println!("Device: {}", mount_entry.fs_spec);
         println!("{:>width$}: {}", "Mount point", mount_entry.fs_file);
-        println!("{:>width$}: {}","FS type", mount_entry.fs_vfstype);
+        println!("{:>width$}: {}", "FS type", mount_entry.fs_vfstype);
         println!("{:>width$}: {}", "Dump", mount_entry.fs_freq);
         println!("{:>width$}: {}", "Check", mount_entry.fs_passno);
         print!("{:>width$}: ", "Options");

procfs/src/crypto.rs

@@ -1,6 +1,5 @@
-
-use procfs_core::ProcResult;
 pub use procfs_core::CryptoTable;
+use procfs_core::ProcResult;
 
 use crate::Current;
 
@@ -12,7 +11,6 @@ pub fn crypto() -> ProcResult<CryptoTable> {
     CryptoTable::current()
 }
 
-
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -23,4 +21,4 @@ mod tests {
         let table = table.expect("CrytoTable should have been read");
         assert!(!table.crypto_blocks.is_empty(), "Crypto table was empty");
     }
-}
+}

procfs/src/lib.rs

@@ -93,6 +93,10 @@ impl SystemInfoInterface for LocalSystemInfo {
     fn is_little_endian(&self) -> bool {
         u16::from_ne_bytes([0, 1]).to_le_bytes() == [0, 1]
     }
+
+    fn kernel_version(&self) -> ProcResult<procfs_core::KernelVersion> {
+        KernelVersion::cached().map(Into::into)
+    }
 }
 
 const LOCAL_SYSTEM_INFO: LocalSystemInfo = LocalSystemInfo;

procfs/src/sys/kernel/mod.rs

@@ -66,7 +66,7 @@ impl Version {
         Self {
             major,
             minor,
-            patch: u16::from_ne_bytes([lo, hi])
+            patch: u16::from_ne_bytes([lo, hi]),
         }
     }
 
@@ -145,6 +145,12 @@ impl cmp::PartialOrd for Version {
     }
 }
 
+impl From<Version> for procfs_core::KernelVersion {
+    fn from(value: Version) -> Self {
+        Self::new(value.major, value.minor, value.patch)
+    }
+}
+
 /// Represents a kernel type
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct Type {

procfs/src/sys/kernel/random.rs

@@ -5,7 +5,7 @@
 use crate::{read_value, write_value, ProcError, ProcResult};
 use std::path::Path;
 
-const RANDOM_ROOT: &str = "/proc/sys/kernel/random"; 
+const RANDOM_ROOT: &str = "/proc/sys/kernel/random";
 
 /// This read-only file gives the available entropy, in bits. This will be a number in the range
 /// 0 to 4096