Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 357 insertions, 0 deletions

diff --git a/library/std/src/thread/local/dynamic_tests.rs b/library/std/src/thread/local/dynamic_tests.rs
new file mode 100644
index 000000000..dd1800416
--- /dev/null
+++ b/library/std/src/thread/local/dynamic_tests.rs
@@ -0,0 +1,40 @@
+use crate::cell::RefCell;
+use crate::collections::HashMap;
+use crate::thread_local;
+
+#[test]
+fn smoke() {
+    fn square(i: i32) -> i32 {
+        i * i
+    }
+    thread_local!(static FOO: i32 = square(3));
+
+    FOO.with(|f| {
+        assert_eq!(*f, 9);
+    });
+}
+
+#[test]
+fn hashmap() {
+    fn map() -> RefCell<HashMap<i32, i32>> {
+        let mut m = HashMap::new();
+        m.insert(1, 2);
+        RefCell::new(m)
+    }
+    thread_local!(static FOO: RefCell<HashMap<i32, i32>> = map());
+
+    FOO.with(|map| {
+        assert_eq!(map.borrow()[&1], 2);
+    });
+}
+
+#[test]
+fn refcell_vec() {
+    thread_local!(static FOO: RefCell<Vec<u32>> = RefCell::new(vec![1, 2, 3]));
+
+    FOO.with(|vec| {
+        assert_eq!(vec.borrow().len(), 3);
+        vec.borrow_mut().push(4);
+        assert_eq!(vec.borrow()[3], 4);
+    });
+}
diff --git a/library/std/src/thread/local/tests.rs b/library/std/src/thread/local/tests.rs
new file mode 100644
index 000000000..1df1ca758
--- /dev/null
+++ b/library/std/src/thread/local/tests.rs
@@ -0,0 +1,317 @@
+use crate::cell::{Cell, UnsafeCell};
+use crate::sync::atomic::{AtomicU8, Ordering};
+use crate::sync::mpsc::{channel, Sender};
+use crate::thread::{self, LocalKey};
+use crate::thread_local;
+
+struct Foo(Sender<()>);
+
+impl Drop for Foo {
+    fn drop(&mut self) {
+        let Foo(ref s) = *self;
+        s.send(()).unwrap();
+    }
+}
+
+#[test]
+fn smoke_no_dtor() {
+    thread_local!(static FOO: Cell<i32> = Cell::new(1));
+    run(&FOO);
+    thread_local!(static FOO2: Cell<i32> = const { Cell::new(1) });
+    run(&FOO2);
+
+    fn run(key: &'static LocalKey<Cell<i32>>) {
+        key.with(|f| {
+            assert_eq!(f.get(), 1);
+            f.set(2);
+        });
+        let t = thread::spawn(move || {
+            key.with(|f| {
+                assert_eq!(f.get(), 1);
+            });
+        });
+        t.join().unwrap();
+
+        key.with(|f| {
+            assert_eq!(f.get(), 2);
+        });
+    }
+}
+
+#[test]
+fn states() {
+    struct Foo(&'static LocalKey<Foo>);
+    impl Drop for Foo {
+        fn drop(&mut self) {
+            assert!(self.0.try_with(|_| ()).is_err());
+        }
+    }
+
+    thread_local!(static FOO: Foo = Foo(&FOO));
+    run(&FOO);
+    thread_local!(static FOO2: Foo = const { Foo(&FOO2) });
+    run(&FOO2);
+
+    fn run(foo: &'static LocalKey<Foo>) {
+        thread::spawn(move || {
+            assert!(foo.try_with(|_| ()).is_ok());
+        })
+        .join()
+        .unwrap();
+    }
+}
+
+#[test]
+fn smoke_dtor() {
+    thread_local!(static FOO: UnsafeCell<Option<Foo>> = UnsafeCell::new(None));
+    run(&FOO);
+    thread_local!(static FOO2: UnsafeCell<Option<Foo>> = const { UnsafeCell::new(None) });
+    run(&FOO2);
+
+    fn run(key: &'static LocalKey<UnsafeCell<Option<Foo>>>) {
+        let (tx, rx) = channel();
+        let t = thread::spawn(move || unsafe {
+            let mut tx = Some(tx);
+            key.with(|f| {
+                *f.get() = Some(Foo(tx.take().unwrap()));
+            });
+        });
+        rx.recv().unwrap();
+        t.join().unwrap();
+    }
+}
+
+#[test]
+fn circular() {
+    struct S1(&'static LocalKey<UnsafeCell<Option<S1>>>, &'static LocalKey<UnsafeCell<Option<S2>>>);
+    struct S2(&'static LocalKey<UnsafeCell<Option<S1>>>, &'static LocalKey<UnsafeCell<Option<S2>>>);
+    thread_local!(static K1: UnsafeCell<Option<S1>> = UnsafeCell::new(None));
+    thread_local!(static K2: UnsafeCell<Option<S2>> = UnsafeCell::new(None));
+    thread_local!(static K3: UnsafeCell<Option<S1>> = const { UnsafeCell::new(None) });
+    thread_local!(static K4: UnsafeCell<Option<S2>> = const { UnsafeCell::new(None) });
+    static mut HITS: usize = 0;
+
+    impl Drop for S1 {
+        fn drop(&mut self) {
+            unsafe {
+                HITS += 1;
+                if self.1.try_with(|_| ()).is_err() {
+                    assert_eq!(HITS, 3);
+                } else {
+                    if HITS == 1 {
+                        self.1.with(|s| *s.get() = Some(S2(self.0, self.1)));
+                    } else {
+                        assert_eq!(HITS, 3);
+                    }
+                }
+            }
+        }
+    }
+    impl Drop for S2 {
+        fn drop(&mut self) {
+            unsafe {
+                HITS += 1;
+                assert!(self.0.try_with(|_| ()).is_ok());
+                assert_eq!(HITS, 2);
+                self.0.with(|s| *s.get() = Some(S1(self.0, self.1)));
+            }
+        }
+    }
+
+    thread::spawn(move || {
+        drop(S1(&K1, &K2));
+    })
+    .join()
+    .unwrap();
+
+    unsafe {
+        HITS = 0;
+    }
+
+    thread::spawn(move || {
+        drop(S1(&K3, &K4));
+    })
+    .join()
+    .unwrap();
+}
+
+#[test]
+fn self_referential() {
+    struct S1(&'static LocalKey<UnsafeCell<Option<S1>>>);
+
+    thread_local!(static K1: UnsafeCell<Option<S1>> = UnsafeCell::new(None));
+    thread_local!(static K2: UnsafeCell<Option<S1>> = const { UnsafeCell::new(None) });
+
+    impl Drop for S1 {
+        fn drop(&mut self) {
+            assert!(self.0.try_with(|_| ()).is_err());
+        }
+    }
+
+    thread::spawn(move || unsafe {
+        K1.with(|s| *s.get() = Some(S1(&K1)));
+    })
+    .join()
+    .unwrap();
+
+    thread::spawn(move || unsafe {
+        K2.with(|s| *s.get() = Some(S1(&K2)));
+    })
+    .join()
+    .unwrap();
+}
+
+// Note that this test will deadlock if TLS destructors aren't run (this
+// requires the destructor to be run to pass the test).
+#[test]
+fn dtors_in_dtors_in_dtors() {
+    struct S1(Sender<()>);
+    thread_local!(static K1: UnsafeCell<Option<S1>> = UnsafeCell::new(None));
+    thread_local!(static K2: UnsafeCell<Option<Foo>> = UnsafeCell::new(None));
+
+    impl Drop for S1 {
+        fn drop(&mut self) {
+            let S1(ref tx) = *self;
+            unsafe {
+                let _ = K2.try_with(|s| *s.get() = Some(Foo(tx.clone())));
+            }
+        }
+    }
+
+    let (tx, rx) = channel();
+    let _t = thread::spawn(move || unsafe {
+        let mut tx = Some(tx);
+        K1.with(|s| *s.get() = Some(S1(tx.take().unwrap())));
+    });
+    rx.recv().unwrap();
+}
+
+#[test]
+fn dtors_in_dtors_in_dtors_const_init() {
+    struct S1(Sender<()>);
+    thread_local!(static K1: UnsafeCell<Option<S1>> = const { UnsafeCell::new(None) });
+    thread_local!(static K2: UnsafeCell<Option<Foo>> = const { UnsafeCell::new(None) });
+
+    impl Drop for S1 {
+        fn drop(&mut self) {
+            let S1(ref tx) = *self;
+            unsafe {
+                let _ = K2.try_with(|s| *s.get() = Some(Foo(tx.clone())));
+            }
+        }
+    }
+
+    let (tx, rx) = channel();
+    let _t = thread::spawn(move || unsafe {
+        let mut tx = Some(tx);
+        K1.with(|s| *s.get() = Some(S1(tx.take().unwrap())));
+    });
+    rx.recv().unwrap();
+}
+
+// This test tests that TLS destructors have run before the thread joins. The
+// test has no false positives (meaning: if the test fails, there's actually
+// an ordering problem). It may have false negatives, where the test passes but
+// join is not guaranteed to be after the TLS destructors. However, false
+// negatives should be exceedingly rare due to judicious use of
+// thread::yield_now and running the test several times.
+#[test]
+fn join_orders_after_tls_destructors() {
+    // We emulate a synchronous MPSC rendezvous channel using only atomics and
+    // thread::yield_now. We can't use std::mpsc as the implementation itself
+    // may rely on thread locals.
+    //
+    // The basic state machine for an SPSC rendezvous channel is:
+    //           FRESH -> THREAD1_WAITING -> MAIN_THREAD_RENDEZVOUS
+    // where the first transition is done by the “receiving” thread and the 2nd
+    // transition is done by the “sending” thread.
+    //
+    // We add an additional state `THREAD2_LAUNCHED` between `FRESH` and
+    // `THREAD1_WAITING` to block until all threads are actually running.
+    //
+    // A thread that joins on the “receiving” thread completion should never
+    // observe the channel in the `THREAD1_WAITING` state. If this does occur,
+    // we switch to the “poison” state `THREAD2_JOINED` and panic all around.
+    // (This is equivalent to “sending” from an alternate producer thread.)
+    const FRESH: u8 = 0;
+    const THREAD2_LAUNCHED: u8 = 1;
+    const THREAD1_WAITING: u8 = 2;
+    const MAIN_THREAD_RENDEZVOUS: u8 = 3;
+    const THREAD2_JOINED: u8 = 4;
+    static SYNC_STATE: AtomicU8 = AtomicU8::new(FRESH);
+
+    for _ in 0..10 {
+        SYNC_STATE.store(FRESH, Ordering::SeqCst);
+
+        let jh = thread::Builder::new()
+            .name("thread1".into())
+            .spawn(move || {
+                struct TlDrop;
+
+                impl Drop for TlDrop {
+                    fn drop(&mut self) {
+                        let mut sync_state = SYNC_STATE.swap(THREAD1_WAITING, Ordering::SeqCst);
+                        loop {
+                            match sync_state {
+                                THREAD2_LAUNCHED | THREAD1_WAITING => thread::yield_now(),
+                                MAIN_THREAD_RENDEZVOUS => break,
+                                THREAD2_JOINED => panic!(
+                                    "Thread 1 still running after thread 2 joined on thread 1"
+                                ),
+                                v => unreachable!("sync state: {}", v),
+                            }
+                            sync_state = SYNC_STATE.load(Ordering::SeqCst);
+                        }
+                    }
+                }
+
+                thread_local! {
+                    static TL_DROP: TlDrop = TlDrop;
+                }
+
+                TL_DROP.with(|_| {});
+
+                loop {
+                    match SYNC_STATE.load(Ordering::SeqCst) {
+                        FRESH => thread::yield_now(),
+                        THREAD2_LAUNCHED => break,
+                        v => unreachable!("sync state: {}", v),
+                    }
+                }
+            })
+            .unwrap();
+
+        let jh2 = thread::Builder::new()
+            .name("thread2".into())
+            .spawn(move || {
+                assert_eq!(SYNC_STATE.swap(THREAD2_LAUNCHED, Ordering::SeqCst), FRESH);
+                jh.join().unwrap();
+                match SYNC_STATE.swap(THREAD2_JOINED, Ordering::SeqCst) {
+                    MAIN_THREAD_RENDEZVOUS => return,
+                    THREAD2_LAUNCHED | THREAD1_WAITING => {
+                        panic!("Thread 2 running after thread 1 join before main thread rendezvous")
+                    }
+                    v => unreachable!("sync state: {:?}", v),
+                }
+            })
+            .unwrap();
+
+        loop {
+            match SYNC_STATE.compare_exchange(
+                THREAD1_WAITING,
+                MAIN_THREAD_RENDEZVOUS,
+                Ordering::SeqCst,
+                Ordering::SeqCst,
+            ) {
+                Ok(_) => break,
+                Err(FRESH) => thread::yield_now(),
+                Err(THREAD2_LAUNCHED) => thread::yield_now(),
+                Err(THREAD2_JOINED) => {
+                    panic!("Main thread rendezvous after thread 2 joined thread 1")
+                }
+                v => unreachable!("sync state: {:?}", v),
+            }
+        }
+        jh2.join().unwrap();
+    }
+}