signal timer (#6535)

* fix waitpid

* signal timer

Lib/test/test_signal.py

@@ -127,8 +127,6 @@ class PosixTests(unittest.TestCase):
         self.assertIn("Terminated", signal.strsignal(signal.SIGTERM))
         self.assertIn("Hangup", signal.strsignal(signal.SIGHUP))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     # Issue 3864, unknown if this affects earlier versions of freebsd also
     def test_interprocess_signal(self):
         dirname = os.path.dirname(__file__)
@@ -820,8 +818,6 @@ class ItimerTest(unittest.TestCase):
         self.hndl_called = True
         signal.setitimer(signal.ITIMER_PROF, 0)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_itimer_exc(self):
         # XXX I'm assuming -1 is an invalid itimer, but maybe some platform
         # defines it ?
@@ -831,16 +827,12 @@ class ItimerTest(unittest.TestCase):
             self.assertRaises(signal.ItimerError,
                               signal.setitimer, signal.ITIMER_REAL, -1)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_itimer_real(self):
         self.itimer = signal.ITIMER_REAL
         signal.setitimer(self.itimer, 1.0)
         signal.pause()
         self.assertEqual(self.hndl_called, True)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     # Issue 3864, unknown if this affects earlier versions of freebsd also
     @unittest.skipIf(sys.platform in ('netbsd5',),
         'itimer not reliable (does not mix well with threading) on some BSDs.')
@@ -861,8 +853,6 @@ class ItimerTest(unittest.TestCase):
         # and the handler should have been called
         self.assertEqual(self.hndl_called, True)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_itimer_prof(self):
         self.itimer = signal.ITIMER_PROF
         signal.signal(signal.SIGPROF, self.sig_prof)
@@ -880,8 +870,6 @@ class ItimerTest(unittest.TestCase):
         # and the handler should have been called
         self.assertEqual(self.hndl_called, True)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_setitimer_tiny(self):
         # bpo-30807: C setitimer() takes a microsecond-resolution interval.
         # Check that float -> timeval conversion doesn't round

crates/vm/src/stdlib/posix.rs

@@ -1738,9 +1738,17 @@ pub mod module {
     #[pyfunction]
     fn waitpid(pid: libc::pid_t, opt: i32, vm: &VirtualMachine) -> PyResult<(libc::pid_t, i32)> {
         let mut status = 0;
-        let pid = unsafe { libc::waitpid(pid, &mut status, opt) };
-        let pid = nix::Error::result(pid).map_err(|err| err.into_pyexception(vm))?;
-        Ok((pid, status))
+        loop {
+            let res = unsafe { libc::waitpid(pid, &mut status, opt) };
+            if res == -1 {
+                if nix::Error::last_raw() == libc::EINTR {
+                    vm.check_signals()?;
+                    continue;
+                }
+                return Err(nix::Error::last().into_pyexception(vm));
+            }
+            return Ok((res, status));
+        }
     }
 
     #[pyfunction]

crates/vm/src/stdlib/signal.rs

@@ -19,6 +19,11 @@ pub(crate) mod _signal {
         convert::{IntoPyException, TryFromBorrowedObject},
     };
     use crate::{PyObjectRef, PyResult, VirtualMachine, signal};
+    #[cfg(unix)]
+    use crate::{
+        builtins::PyTypeRef,
+        function::{ArgIntoFloat, OptionalArg},
+    };
     use std::sync::atomic::{self, Ordering};
 
     #[cfg(any(unix, windows))]
@@ -89,6 +94,18 @@ pub(crate) mod _signal {
         fn siginterrupt(sig: i32, flag: i32) -> i32;
     }
 
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    mod ffi {
+        unsafe extern "C" {
+            pub fn getitimer(which: libc::c_int, curr_value: *mut libc::itimerval) -> libc::c_int;
+            pub fn setitimer(
+                which: libc::c_int,
+                new_value: *const libc::itimerval,
+                old_value: *mut libc::itimerval,
+            ) -> libc::c_int;
+        }
+    }
+
     #[pyattr]
     use crate::signal::NSIG;
 
@@ -114,6 +131,31 @@ pub(crate) mod _signal {
     #[pyattr]
     use libc::{SIGPWR, SIGSTKFLT};
 
+    // Interval timer constants
+    #[cfg(all(unix, not(target_os = "android")))]
+    #[pyattr]
+    use libc::{ITIMER_PROF, ITIMER_REAL, ITIMER_VIRTUAL};
+
+    #[cfg(target_os = "android")]
+    #[pyattr]
+    const ITIMER_REAL: libc::c_int = 0;
+    #[cfg(target_os = "android")]
+    #[pyattr]
+    const ITIMER_VIRTUAL: libc::c_int = 1;
+    #[cfg(target_os = "android")]
+    #[pyattr]
+    const ITIMER_PROF: libc::c_int = 2;
+
+    #[cfg(unix)]
+    #[pyattr(name = "ItimerError", once)]
+    fn itimer_error(vm: &VirtualMachine) -> PyTypeRef {
+        vm.ctx.new_exception_type(
+            "signal",
+            "ItimerError",
+            Some(vec![vm.ctx.exceptions.os_error.to_owned()]),
+        )
+    }
+
     #[cfg(any(unix, windows))]
     pub(super) fn init_signal_handlers(
         module: &Py<crate::builtins::PyModule>,
@@ -216,6 +258,80 @@ pub(crate) mod _signal {
         prev_time.unwrap_or(0)
     }
 
+    #[cfg(unix)]
+    #[pyfunction]
+    fn pause(vm: &VirtualMachine) -> PyResult<()> {
+        unsafe { libc::pause() };
+        signal::check_signals(vm)?;
+        Ok(())
+    }
+
+    #[cfg(unix)]
+    fn timeval_to_double(tv: &libc::timeval) -> f64 {
+        tv.tv_sec as f64 + (tv.tv_usec as f64 / 1_000_000.0)
+    }
+
+    #[cfg(unix)]
+    fn double_to_timeval(val: f64) -> libc::timeval {
+        libc::timeval {
+            tv_sec: val.trunc() as _,
+            tv_usec: ((val.fract()) * 1_000_000.0) as _,
+        }
+    }
+
+    #[cfg(unix)]
+    fn itimerval_to_tuple(it: &libc::itimerval) -> (f64, f64) {
+        (
+            timeval_to_double(&it.it_value),
+            timeval_to_double(&it.it_interval),
+        )
+    }
+
+    #[cfg(unix)]
+    #[pyfunction]
+    fn setitimer(
+        which: i32,
+        seconds: ArgIntoFloat,
+        interval: OptionalArg<ArgIntoFloat>,
+        vm: &VirtualMachine,
+    ) -> PyResult<(f64, f64)> {
+        let seconds: f64 = seconds.into();
+        let interval: f64 = interval.map(|v| v.into()).unwrap_or(0.0);
+        let new = libc::itimerval {
+            it_value: double_to_timeval(seconds),
+            it_interval: double_to_timeval(interval),
+        };
+        let mut old = std::mem::MaybeUninit::<libc::itimerval>::uninit();
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        let ret = unsafe { ffi::setitimer(which, &new, old.as_mut_ptr()) };
+        #[cfg(not(any(target_os = "linux", target_os = "android")))]
+        let ret = unsafe { libc::setitimer(which, &new, old.as_mut_ptr()) };
+        if ret != 0 {
+            let err = std::io::Error::last_os_error();
+            let itimer_error = itimer_error(vm);
+            return Err(vm.new_exception_msg(itimer_error, err.to_string()));
+        }
+        let old = unsafe { old.assume_init() };
+        Ok(itimerval_to_tuple(&old))
+    }
+
+    #[cfg(unix)]
+    #[pyfunction]
+    fn getitimer(which: i32, vm: &VirtualMachine) -> PyResult<(f64, f64)> {
+        let mut old = std::mem::MaybeUninit::<libc::itimerval>::uninit();
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        let ret = unsafe { ffi::getitimer(which, old.as_mut_ptr()) };
+        #[cfg(not(any(target_os = "linux", target_os = "android")))]
+        let ret = unsafe { libc::getitimer(which, old.as_mut_ptr()) };
+        if ret != 0 {
+            let err = std::io::Error::last_os_error();
+            let itimer_error = itimer_error(vm);
+            return Err(vm.new_exception_msg(itimer_error, err.to_string()));
+        }
+        let old = unsafe { old.assume_init() };
+        Ok(itimerval_to_tuple(&old))
+    }
+
     #[pyfunction]
     fn default_int_handler(
         _signum: PyObjectRef,