Add waitpid (#334)

Author: quininer

io-uring-test/src/main.rs

@@ -156,6 +156,9 @@ fn test<S: squeue::EntryMarker, C: cqueue::EntryMarker>(
     tests::futex::test_futex_wake(&mut ring, &test)?;
     tests::futex::test_futex_waitv(&mut ring, &test)?;
 
+    // os (process)
+    tests::os::test_waitid(&mut ring, &test)?;
+
     // regression test
     tests::regression::test_issue154(&mut ring, &test)?;
 

io-uring-test/src/tests/mod.rs

@@ -2,6 +2,7 @@ pub mod cancel;
 pub mod fs;
 pub mod futex;
 pub mod net;
+pub mod os;
 pub mod poll;
 pub mod queue;
 pub mod register;

io-uring-test/src/tests/os.rs

@@ -0,0 +1,46 @@
+use crate::Test;
+use io_uring::{cqueue, opcode, squeue, IoUring};
+use std::process::{Command, Stdio};
+use std::thread;
+use std::time::Duration;
+
+pub fn test_waitid<S: squeue::EntryMarker, C: cqueue::EntryMarker>(
+    ring: &mut IoUring<S, C>,
+    test: &Test,
+) -> anyhow::Result<()> {
+    require!(
+        test;
+        test.probe.is_supported(opcode::WaitId::CODE);
+    );
+
+    let mut child = Command::new("cat")
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .stderr(Stdio::null())
+        .spawn()?;
+
+    let waitid_e = opcode::WaitId::new(libc::P_PID, child.id(), libc::WEXITED);
+
+    unsafe {
+        let mut sq = ring.submission();
+        sq.push(&waitid_e.build().user_data(0x110).into())
+            .expect("queue is full");
+    }
+
+    ring.submit()?;
+    thread::sleep(Duration::from_millis(100));
+    assert_eq!(ring.completion().len(), 0);
+
+    // close cat
+    child.stdin = None;
+    child.stdout = None;
+
+    ring.submit_and_wait(1)?;
+    let cqes: Vec<cqueue::Entry> = ring.completion().map(Into::into).collect();
+
+    assert_eq!(cqes.len(), 1);
+    assert_eq!(cqes[0].user_data(), 0x110);
+    assert_eq!(cqes[0].result(), 0);
+
+    Ok(())
+}

src/opcode.rs

@@ -1879,6 +1879,34 @@ opcode! {
     }
 }
 
+opcode! {
+    /// Issue the equivalent of a `waitid(2)` system call.
+    ///
+    /// Available since kernel 6.7.
+    #[derive(Debug)]
+    pub struct WaitId {
+        idtype: { libc::idtype_t },
+        id: { libc::id_t },
+        options: { libc::c_int },
+        ;;
+        infop: *const libc::siginfo_t = std::ptr::null(),
+        flags: libc::c_uint = 0,
+    }
+
+    pub const CODE = sys::IORING_OP_WAITID;
+
+    pub fn build(self) -> Entry {
+        let mut sqe = sqe_zeroed();
+        sqe.opcode = Self::CODE;
+        sqe.fd = self.id as _;
+        sqe.len = self.idtype as _;
+        sqe.__bindgen_anon_3.waitid_flags = self.flags;
+        sqe.__bindgen_anon_5.file_index = self.options as _;
+        sqe.__bindgen_anon_1.addr2 = self.infop as _;
+        Entry(sqe)
+    }
+}
+
 // === 6.8 ===
 
 opcode! {