diff options
Diffstat (limited to 'library/std/src')
| -rw-r--r-- | library/std/src/keyword_docs.rs | 122 | ||||
| -rw-r--r-- | library/std/src/lib.rs | 2 | ||||
| -rw-r--r-- | library/std/src/os/fd/owned.rs | 8 | ||||
| -rw-r--r-- | library/std/src/os/fd/raw.rs | 8 | ||||
| -rw-r--r-- | library/std/src/os/windows/io/handle.rs | 8 | ||||
| -rw-r--r-- | library/std/src/os/windows/io/socket.rs | 8 | ||||
| -rw-r--r-- | library/std/src/sync/mutex.rs | 110 | ||||
| -rw-r--r-- | library/std/src/sync/mutex/tests.rs | 161 | ||||
| -rw-r--r-- | library/std/src/sync/poison.rs | 35 | ||||
| -rw-r--r-- | library/std/src/sync/rwlock.rs | 128 | ||||
| -rw-r--r-- | library/std/src/sync/rwlock/tests.rs | 169 | ||||
| -rw-r--r-- | library/std/src/sys/pal/unix/net.rs | 1 |
12 files changed, 612 insertions, 148 deletions
diff --git a/library/std/src/keyword_docs.rs b/library/std/src/keyword_docs.rs index 4302e24781e..0c526eafdf3 100644 --- a/library/std/src/keyword_docs.rs +++ b/library/std/src/keyword_docs.rs @@ -807,64 +807,6 @@ mod in_keyword {} /// [Reference]: ../reference/statements.html#let-statements mod let_keyword {} -#[doc(keyword = "while")] -// -/// Loop while a condition is upheld. -/// -/// A `while` expression is used for predicate loops. The `while` expression runs the conditional -/// expression before running the loop body, then runs the loop body if the conditional -/// expression evaluates to `true`, or exits the loop otherwise. -/// -/// ```rust -/// let mut counter = 0; -/// -/// while counter < 10 { -/// println!("{counter}"); -/// counter += 1; -/// } -/// ``` -/// -/// Like the [`for`] expression, we can use `break` and `continue`. A `while` expression -/// cannot break with a value and always evaluates to `()` unlike [`loop`]. -/// -/// ```rust -/// let mut i = 1; -/// -/// while i < 100 { -/// i *= 2; -/// if i == 64 { -/// break; // Exit when `i` is 64. -/// } -/// } -/// ``` -/// -/// As `if` expressions have their pattern matching variant in `if let`, so too do `while` -/// expressions with `while let`. The `while let` expression matches the pattern against the -/// expression, then runs the loop body if pattern matching succeeds, or exits the loop otherwise. -/// We can use `break` and `continue` in `while let` expressions just like in `while`. -/// -/// ```rust -/// let mut counter = Some(0); -/// -/// while let Some(i) = counter { -/// if i == 10 { -/// counter = None; -/// } else { -/// println!("{i}"); -/// counter = Some (i + 1); -/// } -/// } -/// ``` -/// -/// For more information on `while` and loops in general, see the [reference]. -/// -/// See also, [`for`], [`loop`]. -/// -/// [`for`]: keyword.for.html -/// [`loop`]: keyword.loop.html -/// [reference]: ../reference/expressions/loop-expr.html#predicate-loops -mod while_keyword {} - #[doc(keyword = "loop")] // /// Loop indefinitely. @@ -1321,10 +1263,10 @@ mod return_keyword {} /// [Reference]: ../reference/items/associated-items.html#methods mod self_keyword {} -// FIXME: Once rustdoc can handle URL conflicts on case insensitive file systems, we can remove the -// three next lines and put back: `#[doc(keyword = "Self")]`. +// FIXME: Once rustdoc can handle URL conflicts on case insensitive file systems, we can replace +// these two lines with `#[doc(keyword = "Self")]` and update `is_doc_keyword` in +// `CheckAttrVisitor`. #[doc(alias = "Self")] -#[allow(rustc::existing_doc_keyword)] #[doc(keyword = "SelfTy")] // /// The implementing type within a [`trait`] or [`impl`] block, or the current type within a type @@ -2343,6 +2285,64 @@ mod use_keyword {} /// [RFC]: https://github.com/rust-lang/rfcs/blob/master/text/0135-where.md mod where_keyword {} +#[doc(keyword = "while")] +// +/// Loop while a condition is upheld. +/// +/// A `while` expression is used for predicate loops. The `while` expression runs the conditional +/// expression before running the loop body, then runs the loop body if the conditional +/// expression evaluates to `true`, or exits the loop otherwise. +/// +/// ```rust +/// let mut counter = 0; +/// +/// while counter < 10 { +/// println!("{counter}"); +/// counter += 1; +/// } +/// ``` +/// +/// Like the [`for`] expression, we can use `break` and `continue`. A `while` expression +/// cannot break with a value and always evaluates to `()` unlike [`loop`]. +/// +/// ```rust +/// let mut i = 1; +/// +/// while i < 100 { +/// i *= 2; +/// if i == 64 { +/// break; // Exit when `i` is 64. +/// } +/// } +/// ``` +/// +/// As `if` expressions have their pattern matching variant in `if let`, so too do `while` +/// expressions with `while let`. The `while let` expression matches the pattern against the +/// expression, then runs the loop body if pattern matching succeeds, or exits the loop otherwise. +/// We can use `break` and `continue` in `while let` expressions just like in `while`. +/// +/// ```rust +/// let mut counter = Some(0); +/// +/// while let Some(i) = counter { +/// if i == 10 { +/// counter = None; +/// } else { +/// println!("{i}"); +/// counter = Some (i + 1); +/// } +/// } +/// ``` +/// +/// For more information on `while` and loops in general, see the [reference]. +/// +/// See also, [`for`], [`loop`]. +/// +/// [`for`]: keyword.for.html +/// [`loop`]: keyword.loop.html +/// [reference]: ../reference/expressions/loop-expr.html#predicate-loops +mod while_keyword {} + // 2018 Edition keywords #[doc(alias = "promise")] diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs index 1cbf51463ea..1c80694ca8f 100644 --- a/library/std/src/lib.rs +++ b/library/std/src/lib.rs @@ -251,7 +251,6 @@ #![allow(explicit_outlives_requirements)] #![allow(unused_lifetimes)] #![allow(internal_features)] -#![deny(rustc::existing_doc_keyword)] #![deny(fuzzy_provenance_casts)] #![deny(unsafe_op_in_unsafe_fn)] #![allow(rustdoc::redundant_explicit_links)] @@ -373,6 +372,7 @@ #![feature(thin_box)] #![feature(try_reserve_kind)] #![feature(try_with_capacity)] +#![feature(unique_rc_arc)] #![feature(vec_into_raw_parts)] // tidy-alphabetical-end // diff --git a/library/std/src/os/fd/owned.rs b/library/std/src/os/fd/owned.rs index 388b8a88a1a..abb13b75f50 100644 --- a/library/std/src/os/fd/owned.rs +++ b/library/std/src/os/fd/owned.rs @@ -428,6 +428,14 @@ impl<T: AsFd + ?Sized> AsFd for crate::rc::Rc<T> { } } +#[unstable(feature = "unique_rc_arc", issue = "112566")] +impl<T: AsFd + ?Sized> AsFd for crate::rc::UniqueRc<T> { + #[inline] + fn as_fd(&self) -> BorrowedFd<'_> { + (**self).as_fd() + } +} + #[stable(feature = "asfd_ptrs", since = "1.64.0")] impl<T: AsFd + ?Sized> AsFd for Box<T> { #[inline] diff --git a/library/std/src/os/fd/raw.rs b/library/std/src/os/fd/raw.rs index 0d99d5492a2..22f5528248a 100644 --- a/library/std/src/os/fd/raw.rs +++ b/library/std/src/os/fd/raw.rs @@ -266,6 +266,14 @@ impl<T: AsRawFd> AsRawFd for crate::rc::Rc<T> { } } +#[unstable(feature = "unique_rc_arc", issue = "112566")] +impl<T: AsRawFd + ?Sized> AsRawFd for crate::rc::UniqueRc<T> { + #[inline] + fn as_raw_fd(&self) -> RawFd { + (**self).as_raw_fd() + } +} + #[stable(feature = "asrawfd_ptrs", since = "1.63.0")] impl<T: AsRawFd> AsRawFd for Box<T> { #[inline] diff --git a/library/std/src/os/windows/io/handle.rs b/library/std/src/os/windows/io/handle.rs index a4fa94e2b96..76f5f549dd2 100644 --- a/library/std/src/os/windows/io/handle.rs +++ b/library/std/src/os/windows/io/handle.rs @@ -485,6 +485,14 @@ impl<T: AsHandle + ?Sized> AsHandle for crate::rc::Rc<T> { } } +#[unstable(feature = "unique_rc_arc", issue = "112566")] +impl<T: AsHandle + ?Sized> AsHandle for crate::rc::UniqueRc<T> { + #[inline] + fn as_handle(&self) -> BorrowedHandle<'_> { + (**self).as_handle() + } +} + #[stable(feature = "as_windows_ptrs", since = "1.71.0")] impl<T: AsHandle + ?Sized> AsHandle for Box<T> { #[inline] diff --git a/library/std/src/os/windows/io/socket.rs b/library/std/src/os/windows/io/socket.rs index 272641ea6c7..c6d7bad9440 100644 --- a/library/std/src/os/windows/io/socket.rs +++ b/library/std/src/os/windows/io/socket.rs @@ -279,6 +279,14 @@ impl<T: AsSocket> AsSocket for crate::rc::Rc<T> { } } +#[unstable(feature = "unique_rc_arc", issue = "112566")] +impl<T: AsSocket + ?Sized> AsSocket for crate::rc::UniqueRc<T> { + #[inline] + fn as_socket(&self) -> BorrowedSocket<'_> { + (**self).as_socket() + } +} + #[stable(feature = "as_windows_ptrs", since = "1.71.0")] impl<T: AsSocket> AsSocket for Box<T> { #[inline] diff --git a/library/std/src/sync/mutex.rs b/library/std/src/sync/mutex.rs index fe2aca031a2..e28c2090afe 100644 --- a/library/std/src/sync/mutex.rs +++ b/library/std/src/sync/mutex.rs @@ -4,10 +4,10 @@ mod tests; use crate::cell::UnsafeCell; use crate::fmt; use crate::marker::PhantomData; -use crate::mem::ManuallyDrop; +use crate::mem::{self, ManuallyDrop}; use crate::ops::{Deref, DerefMut}; use crate::ptr::NonNull; -use crate::sync::{LockResult, TryLockError, TryLockResult, poison}; +use crate::sync::{LockResult, PoisonError, TryLockError, TryLockResult, poison}; use crate::sys::sync as sys; /// A mutual exclusion primitive useful for protecting shared data @@ -273,6 +273,100 @@ impl<T> Mutex<T> { pub const fn new(t: T) -> Mutex<T> { Mutex { inner: sys::Mutex::new(), poison: poison::Flag::new(), data: UnsafeCell::new(t) } } + + /// Returns the contained value by cloning it. + /// + /// # Errors + /// + /// If another user of this mutex panicked while holding the mutex, then + /// this call will return an error instead. + /// + /// # Examples + /// + /// ``` + /// #![feature(lock_value_accessors)] + /// + /// use std::sync::Mutex; + /// + /// let mut mutex = Mutex::new(7); + /// + /// assert_eq!(mutex.get_cloned().unwrap(), 7); + /// ``` + #[unstable(feature = "lock_value_accessors", issue = "133407")] + pub fn get_cloned(&self) -> Result<T, PoisonError<()>> + where + T: Clone, + { + match self.lock() { + Ok(guard) => Ok((*guard).clone()), + Err(_) => Err(PoisonError::new(())), + } + } + + /// Sets the contained value. + /// + /// # Errors + /// + /// If another user of this mutex panicked while holding the mutex, then + /// this call will return an error containing the provided `value` instead. + /// + /// # Examples + /// + /// ``` + /// #![feature(lock_value_accessors)] + /// + /// use std::sync::Mutex; + /// + /// let mut mutex = Mutex::new(7); + /// + /// assert_eq!(mutex.get_cloned().unwrap(), 7); + /// mutex.set(11).unwrap(); + /// assert_eq!(mutex.get_cloned().unwrap(), 11); + /// ``` + #[unstable(feature = "lock_value_accessors", issue = "133407")] + pub fn set(&self, value: T) -> Result<(), PoisonError<T>> { + if mem::needs_drop::<T>() { + // If the contained value has non-trivial destructor, we + // call that destructor after the lock being released. + self.replace(value).map(drop) + } else { + match self.lock() { + Ok(mut guard) => { + *guard = value; + + Ok(()) + } + Err(_) => Err(PoisonError::new(value)), + } + } + } + + /// Replaces the contained value with `value`, and returns the old contained value. + /// + /// # Errors + /// + /// If another user of this mutex panicked while holding the mutex, then + /// this call will return an error containing the provided `value` instead. + /// + /// # Examples + /// + /// ``` + /// #![feature(lock_value_accessors)] + /// + /// use std::sync::Mutex; + /// + /// let mut mutex = Mutex::new(7); + /// + /// assert_eq!(mutex.replace(11).unwrap(), 7); + /// assert_eq!(mutex.get_cloned().unwrap(), 11); + /// ``` + #[unstable(feature = "lock_value_accessors", issue = "133407")] + pub fn replace(&self, value: T) -> LockResult<T> { + match self.lock() { + Ok(mut guard) => Ok(mem::replace(&mut *guard, value)), + Err(_) => Err(PoisonError::new(value)), + } + } } impl<T: ?Sized> Mutex<T> { @@ -290,7 +384,8 @@ impl<T: ?Sized> Mutex<T> { /// # Errors /// /// If another user of this mutex panicked while holding the mutex, then - /// this call will return an error once the mutex is acquired. + /// this call will return an error once the mutex is acquired. The acquired + /// mutex guard will be contained in the returned error. /// /// # Panics /// @@ -331,7 +426,8 @@ impl<T: ?Sized> Mutex<T> { /// /// If another user of this mutex panicked while holding the mutex, then /// this call will return the [`Poisoned`] error if the mutex would - /// otherwise be acquired. + /// otherwise be acquired. An acquired lock guard will be contained + /// in the returned error. /// /// If the mutex could not be acquired because it is already locked, then /// this call will return the [`WouldBlock`] error. @@ -438,7 +534,8 @@ impl<T: ?Sized> Mutex<T> { /// # Errors /// /// If another user of this mutex panicked while holding the mutex, then - /// this call will return an error instead. + /// this call will return an error containing the the underlying data + /// instead. /// /// # Examples /// @@ -465,7 +562,8 @@ impl<T: ?Sized> Mutex<T> { /// # Errors /// /// If another user of this mutex panicked while holding the mutex, then - /// this call will return an error instead. + /// this call will return an error containing a mutable reference to the + /// underlying data instead. /// /// # Examples /// diff --git a/library/std/src/sync/mutex/tests.rs b/library/std/src/sync/mutex/tests.rs index 19ec096c593..395c8aada08 100644 --- a/library/std/src/sync/mutex/tests.rs +++ b/library/std/src/sync/mutex/tests.rs @@ -1,13 +1,34 @@ +use crate::fmt::Debug; +use crate::ops::FnMut; +use crate::panic::{self, AssertUnwindSafe}; use crate::sync::atomic::{AtomicUsize, Ordering}; use crate::sync::mpsc::channel; use crate::sync::{Arc, Condvar, MappedMutexGuard, Mutex, MutexGuard, TryLockError}; -use crate::thread; +use crate::{hint, mem, thread}; struct Packet<T>(Arc<(Mutex<T>, Condvar)>); #[derive(Eq, PartialEq, Debug)] struct NonCopy(i32); +#[derive(Eq, PartialEq, Debug)] +struct NonCopyNeedsDrop(i32); + +impl Drop for NonCopyNeedsDrop { + fn drop(&mut self) { + hint::black_box(()); + } +} + +#[test] +fn test_needs_drop() { + assert!(!mem::needs_drop::<NonCopy>()); + assert!(mem::needs_drop::<NonCopyNeedsDrop>()); +} + +#[derive(Clone, Eq, PartialEq, Debug)] +struct Cloneable(i32); + #[test] fn smoke() { let m = Mutex::new(()); @@ -57,6 +78,21 @@ fn try_lock() { *m.try_lock().unwrap() = (); } +fn new_poisoned_mutex<T>(value: T) -> Mutex<T> { + let mutex = Mutex::new(value); + + let catch_unwind_result = panic::catch_unwind(AssertUnwindSafe(|| { + let _guard = mutex.lock().unwrap(); + + panic!("test panic to poison mutex"); + })); + + assert!(catch_unwind_result.is_err()); + assert!(mutex.is_poisoned()); + + mutex +} + #[test] fn test_into_inner() { let m = Mutex::new(NonCopy(10)); @@ -83,22 +119,32 @@ fn test_into_inner_drop() { #[test] fn test_into_inner_poison() { - let m = Arc::new(Mutex::new(NonCopy(10))); - let m2 = m.clone(); - let _ = thread::spawn(move || { - let _lock = m2.lock().unwrap(); - panic!("test panic in inner thread to poison mutex"); - }) - .join(); + let m = new_poisoned_mutex(NonCopy(10)); - assert!(m.is_poisoned()); - match Arc::try_unwrap(m).unwrap().into_inner() { + match m.into_inner() { Err(e) => assert_eq!(e.into_inner(), NonCopy(10)), Ok(x) => panic!("into_inner of poisoned Mutex is Ok: {x:?}"), } } #[test] +fn test_get_cloned() { + let m = Mutex::new(Cloneable(10)); + + assert_eq!(m.get_cloned().unwrap(), Cloneable(10)); +} + +#[test] +fn test_get_cloned_poison() { + let m = new_poisoned_mutex(Cloneable(10)); + + match m.get_cloned() { + Err(e) => assert_eq!(e.into_inner(), ()), + Ok(x) => panic!("get of poisoned Mutex is Ok: {x:?}"), + } +} + +#[test] fn test_get_mut() { let mut m = Mutex::new(NonCopy(10)); *m.get_mut().unwrap() = NonCopy(20); @@ -107,22 +153,91 @@ fn test_get_mut() { #[test] fn test_get_mut_poison() { - let m = Arc::new(Mutex::new(NonCopy(10))); - let m2 = m.clone(); - let _ = thread::spawn(move || { - let _lock = m2.lock().unwrap(); - panic!("test panic in inner thread to poison mutex"); - }) - .join(); + let mut m = new_poisoned_mutex(NonCopy(10)); - assert!(m.is_poisoned()); - match Arc::try_unwrap(m).unwrap().get_mut() { + match m.get_mut() { Err(e) => assert_eq!(*e.into_inner(), NonCopy(10)), Ok(x) => panic!("get_mut of poisoned Mutex is Ok: {x:?}"), } } #[test] +fn test_set() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = Mutex::new(init()); + + assert_eq!(*m.lock().unwrap(), init()); + m.set(value()).unwrap(); + assert_eq!(*m.lock().unwrap(), value()); + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] +fn test_set_poison() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = new_poisoned_mutex(init()); + + match m.set(value()) { + Err(e) => { + assert_eq!(e.into_inner(), value()); + assert_eq!(m.into_inner().unwrap_err().into_inner(), init()); + } + Ok(x) => panic!("set of poisoned Mutex is Ok: {x:?}"), + } + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] +fn test_replace() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = Mutex::new(init()); + + assert_eq!(*m.lock().unwrap(), init()); + assert_eq!(m.replace(value()).unwrap(), init()); + assert_eq!(*m.lock().unwrap(), value()); + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] +fn test_replace_poison() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = new_poisoned_mutex(init()); + + match m.replace(value()) { + Err(e) => { + assert_eq!(e.into_inner(), value()); + assert_eq!(m.into_inner().unwrap_err().into_inner(), init()); + } + Ok(x) => panic!("replace of poisoned Mutex is Ok: {x:?}"), + } + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] fn test_mutex_arc_condvar() { let packet = Packet(Arc::new((Mutex::new(false), Condvar::new()))); let packet2 = Packet(packet.0.clone()); @@ -269,7 +384,7 @@ fn test_mapping_mapped_guard() { fn panic_while_mapping_unlocked_poison() { let lock = Mutex::new(()); - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.lock().unwrap(); let _guard = MutexGuard::map::<(), _>(guard, |_| panic!()); }); @@ -282,7 +397,7 @@ fn panic_while_mapping_unlocked_poison() { Err(TryLockError::Poisoned(_)) => {} } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.lock().unwrap(); let _guard = MutexGuard::try_map::<(), _>(guard, |_| panic!()); }); @@ -295,7 +410,7 @@ fn panic_while_mapping_unlocked_poison() { Err(TryLockError::Poisoned(_)) => {} } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.lock().unwrap(); let guard = MutexGuard::map::<(), _>(guard, |val| val); let _guard = MappedMutexGuard::map::<(), _>(guard, |_| panic!()); @@ -309,7 +424,7 @@ fn panic_while_mapping_unlocked_poison() { Err(TryLockError::Poisoned(_)) => {} } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.lock().unwrap(); let guard = MutexGuard::map::<(), _>(guard, |val| val); let _guard = MappedMutexGuard::try_map::<(), _>(guard, |_| panic!()); diff --git a/library/std/src/sync/poison.rs b/library/std/src/sync/poison.rs index da66a088e51..9eb900c2103 100644 --- a/library/std/src/sync/poison.rs +++ b/library/std/src/sync/poison.rs @@ -87,8 +87,8 @@ pub struct Guard { /// /// Both [`Mutex`]es and [`RwLock`]s are poisoned whenever a thread fails while the lock /// is held. The precise semantics for when a lock is poisoned is documented on -/// each lock, but once a lock is poisoned then all future acquisitions will -/// return this error. +/// each lock. For a lock in the poisoned state, unless the state is cleared manually, +/// all future acquisitions will return this error. /// /// # Examples /// @@ -118,7 +118,7 @@ pub struct Guard { /// [`RwLock`]: crate::sync::RwLock #[stable(feature = "rust1", since = "1.0.0")] pub struct PoisonError<T> { - guard: T, + data: T, #[cfg(not(panic = "unwind"))] _never: !, } @@ -147,14 +147,15 @@ pub enum TryLockError<T> { /// A type alias for the result of a lock method which can be poisoned. /// /// The [`Ok`] variant of this result indicates that the primitive was not -/// poisoned, and the `Guard` is contained within. The [`Err`] variant indicates +/// poisoned, and the operation result is contained within. The [`Err`] variant indicates /// that the primitive was poisoned. Note that the [`Err`] variant *also* carries -/// the associated guard, and it can be acquired through the [`into_inner`] -/// method. +/// an associated value assigned by the lock method, and it can be acquired through the +/// [`into_inner`] method. The semantics of the associated value depends on the corresponding +/// lock method. /// /// [`into_inner`]: PoisonError::into_inner #[stable(feature = "rust1", since = "1.0.0")] -pub type LockResult<Guard> = Result<Guard, PoisonError<Guard>>; +pub type LockResult<T> = Result<T, PoisonError<T>>; /// A type alias for the result of a nonblocking locking method. /// @@ -195,8 +196,8 @@ impl<T> PoisonError<T> { /// This method may panic if std was built with `panic="abort"`. #[cfg(panic = "unwind")] #[stable(feature = "sync_poison", since = "1.2.0")] - pub fn new(guard: T) -> PoisonError<T> { - PoisonError { guard } + pub fn new(data: T) -> PoisonError<T> { + PoisonError { data } } /// Creates a `PoisonError`. @@ -208,12 +209,12 @@ impl<T> PoisonError<T> { #[cfg(not(panic = "unwind"))] #[stable(feature = "sync_poison", since = "1.2.0")] #[track_caller] - pub fn new(_guard: T) -> PoisonError<T> { + pub fn new(_data: T) -> PoisonError<T> { panic!("PoisonError created in a libstd built with panic=\"abort\"") } /// Consumes this error indicating that a lock is poisoned, returning the - /// underlying guard to allow access regardless. + /// associated data. /// /// # Examples /// @@ -238,21 +239,21 @@ impl<T> PoisonError<T> { /// ``` #[stable(feature = "sync_poison", since = "1.2.0")] pub fn into_inner(self) -> T { - self.guard + self.data } /// Reaches into this error indicating that a lock is poisoned, returning a - /// reference to the underlying guard to allow access regardless. + /// reference to the associated data. #[stable(feature = "sync_poison", since = "1.2.0")] pub fn get_ref(&self) -> &T { - &self.guard + &self.data } /// Reaches into this error indicating that a lock is poisoned, returning a - /// mutable reference to the underlying guard to allow access regardless. + /// mutable reference to the associated data. #[stable(feature = "sync_poison", since = "1.2.0")] pub fn get_mut(&mut self) -> &mut T { - &mut self.guard + &mut self.data } } @@ -322,6 +323,6 @@ where match result { Ok(t) => Ok(f(t)), #[cfg(panic = "unwind")] - Err(PoisonError { guard }) => Err(PoisonError::new(f(guard))), + Err(PoisonError { data }) => Err(PoisonError::new(f(data))), } } diff --git a/library/std/src/sync/rwlock.rs b/library/std/src/sync/rwlock.rs index d55d1c80dca..1519baf99a8 100644 --- a/library/std/src/sync/rwlock.rs +++ b/library/std/src/sync/rwlock.rs @@ -4,7 +4,7 @@ mod tests; use crate::cell::UnsafeCell; use crate::fmt; use crate::marker::PhantomData; -use crate::mem::{ManuallyDrop, forget}; +use crate::mem::{self, ManuallyDrop, forget}; use crate::ops::{Deref, DerefMut}; use crate::ptr::NonNull; use crate::sync::{LockResult, PoisonError, TryLockError, TryLockResult, poison}; @@ -224,6 +224,103 @@ impl<T> RwLock<T> { pub const fn new(t: T) -> RwLock<T> { RwLock { inner: sys::RwLock::new(), poison: poison::Flag::new(), data: UnsafeCell::new(t) } } + + /// Returns the contained value by cloning it. + /// + /// # Errors + /// + /// This function will return an error if the `RwLock` is poisoned. An + /// `RwLock` is poisoned whenever a writer panics while holding an exclusive + /// lock. + /// + /// # Examples + /// + /// ``` + /// #![feature(lock_value_accessors)] + /// + /// use std::sync::RwLock; + /// + /// let mut lock = RwLock::new(7); + /// + /// assert_eq!(lock.get_cloned().unwrap(), 7); + /// ``` + #[unstable(feature = "lock_value_accessors", issue = "133407")] + pub fn get_cloned(&self) -> Result<T, PoisonError<()>> + where + T: Clone, + { + match self.read() { + Ok(guard) => Ok((*guard).clone()), + Err(_) => Err(PoisonError::new(())), + } + } + + /// Sets the contained value. + /// + /// # Errors + /// + /// This function will return an error containing the provided `value` if + /// the `RwLock` is poisoned. An `RwLock` is poisoned whenever a writer + /// panics while holding an exclusive lock. + /// + /// # Examples + /// + /// ``` + /// #![feature(lock_value_accessors)] + /// + /// use std::sync::RwLock; + /// + /// let mut lock = RwLock::new(7); + /// + /// assert_eq!(lock.get_cloned().unwrap(), 7); + /// lock.set(11).unwrap(); + /// assert_eq!(lock.get_cloned().unwrap(), 11); + /// ``` + #[unstable(feature = "lock_value_accessors", issue = "133407")] + pub fn set(&self, value: T) -> Result<(), PoisonError<T>> { + if mem::needs_drop::<T>() { + // If the contained value has non-trivial destructor, we + // call that destructor after the lock being released. + self.replace(value).map(drop) + } else { + match self.write() { + Ok(mut guard) => { + *guard = value; + + Ok(()) + } + Err(_) => Err(PoisonError::new(value)), + } + } + } + + /// Replaces the contained value with `value`, and returns the old contained value. + /// + /// # Errors + /// + /// This function will return an error containing the provided `value` if + /// the `RwLock` is poisoned. An `RwLock` is poisoned whenever a writer + /// panics while holding an exclusive lock. + /// + /// # Examples + /// + /// ``` + /// #![feature(lock_value_accessors)] + /// + /// use std::sync::RwLock; + /// + /// let mut lock = RwLock::new(7); + /// + /// assert_eq!(lock.replace(11).unwrap(), 7); + /// assert_eq!(lock.get_cloned().unwrap(), 11); + /// ``` + #[unstable(feature = "lock_value_accessors", issue = "133407")] + pub fn replace(&self, value: T) -> LockResult<T> { + match self.write() { + Ok(mut guard) => Ok(mem::replace(&mut *guard, value)), + Err(_) => Err(PoisonError::new(value)), + } + } } impl<T: ?Sized> RwLock<T> { @@ -244,7 +341,8 @@ impl<T: ?Sized> RwLock<T> { /// This function will return an error if the `RwLock` is poisoned. An /// `RwLock` is poisoned whenever a writer panics while holding an exclusive /// lock. The failure will occur immediately after the lock has been - /// acquired. + /// acquired. The acquired lock guard will be contained in the returned + /// error. /// /// # Panics /// @@ -292,7 +390,8 @@ impl<T: ?Sized> RwLock<T> { /// This function will return the [`Poisoned`] error if the `RwLock` is /// poisoned. An `RwLock` is poisoned whenever a writer panics while holding /// an exclusive lock. `Poisoned` will only be returned if the lock would - /// have otherwise been acquired. + /// have otherwise been acquired. An acquired lock guard will be contained + /// in the returned error. /// /// This function will return the [`WouldBlock`] error if the `RwLock` could /// not be acquired because it was already locked exclusively. @@ -337,7 +436,8 @@ impl<T: ?Sized> RwLock<T> { /// /// This function will return an error if the `RwLock` is poisoned. An /// `RwLock` is poisoned whenever a writer panics while holding an exclusive - /// lock. An error will be returned when the lock is acquired. + /// lock. An error will be returned when the lock is acquired. The acquired + /// lock guard will be contained in the returned error. /// /// # Panics /// @@ -380,7 +480,8 @@ impl<T: ?Sized> RwLock<T> { /// This function will return the [`Poisoned`] error if the `RwLock` is /// poisoned. An `RwLock` is poisoned whenever a writer panics while holding /// an exclusive lock. `Poisoned` will only be returned if the lock would - /// have otherwise been acquired. + /// have otherwise been acquired. An acquired lock guard will be contained + /// in the returned error. /// /// This function will return the [`WouldBlock`] error if the `RwLock` could /// not be acquired because it was already locked exclusively. @@ -481,10 +582,10 @@ impl<T: ?Sized> RwLock<T> { /// /// # Errors /// - /// This function will return an error if the `RwLock` is poisoned. An - /// `RwLock` is poisoned whenever a writer panics while holding an exclusive - /// lock. An error will only be returned if the lock would have otherwise - /// been acquired. + /// This function will return an error containing the underlying data if + /// the `RwLock` is poisoned. An `RwLock` is poisoned whenever a writer + /// panics while holding an exclusive lock. An error will only be returned + /// if the lock would have otherwise been acquired. /// /// # Examples /// @@ -514,10 +615,11 @@ impl<T: ?Sized> RwLock<T> { /// /// # Errors /// - /// This function will return an error if the `RwLock` is poisoned. An - /// `RwLock` is poisoned whenever a writer panics while holding an exclusive - /// lock. An error will only be returned if the lock would have otherwise - /// been acquired. + /// This function will return an error containing a mutable reference to + /// the underlying data if the `RwLock` is poisoned. An `RwLock` is + /// poisoned whenever a writer panics while holding an exclusive lock. + /// An error will only be returned if the lock would have otherwise been + /// acquired. /// /// # Examples /// diff --git a/library/std/src/sync/rwlock/tests.rs b/library/std/src/sync/rwlock/tests.rs index 48d442921f7..057c2f1a5d7 100644 --- a/library/std/src/sync/rwlock/tests.rs +++ b/library/std/src/sync/rwlock/tests.rs @@ -1,16 +1,37 @@ use rand::Rng; +use crate::fmt::Debug; +use crate::ops::FnMut; +use crate::panic::{self, AssertUnwindSafe}; use crate::sync::atomic::{AtomicUsize, Ordering}; use crate::sync::mpsc::channel; use crate::sync::{ Arc, MappedRwLockReadGuard, MappedRwLockWriteGuard, RwLock, RwLockReadGuard, RwLockWriteGuard, TryLockError, }; -use crate::thread; +use crate::{hint, mem, thread}; #[derive(Eq, PartialEq, Debug)] struct NonCopy(i32); +#[derive(Eq, PartialEq, Debug)] +struct NonCopyNeedsDrop(i32); + +impl Drop for NonCopyNeedsDrop { + fn drop(&mut self) { + hint::black_box(()); + } +} + +#[test] +fn test_needs_drop() { + assert!(!mem::needs_drop::<NonCopy>()); + assert!(mem::needs_drop::<NonCopyNeedsDrop>()); +} + +#[derive(Clone, Eq, PartialEq, Debug)] +struct Cloneable(i32); + #[test] fn smoke() { let l = RwLock::new(()); @@ -255,6 +276,21 @@ fn test_rwlock_try_write() { drop(mapped_read_guard); } +fn new_poisoned_rwlock<T>(value: T) -> RwLock<T> { + let lock = RwLock::new(value); + + let catch_unwind_result = panic::catch_unwind(AssertUnwindSafe(|| { + let _guard = lock.write().unwrap(); + + panic!("test panic to poison RwLock"); + })); + + assert!(catch_unwind_result.is_err()); + assert!(lock.is_poisoned()); + + lock +} + #[test] fn test_into_inner() { let m = RwLock::new(NonCopy(10)); @@ -281,22 +317,32 @@ fn test_into_inner_drop() { #[test] fn test_into_inner_poison() { - let m = Arc::new(RwLock::new(NonCopy(10))); - let m2 = m.clone(); - let _ = thread::spawn(move || { - let _lock = m2.write().unwrap(); - panic!("test panic in inner thread to poison RwLock"); - }) - .join(); + let m = new_poisoned_rwlock(NonCopy(10)); - assert!(m.is_poisoned()); - match Arc::try_unwrap(m).unwrap().into_inner() { + match m.into_inner() { Err(e) => assert_eq!(e.into_inner(), NonCopy(10)), Ok(x) => panic!("into_inner of poisoned RwLock is Ok: {x:?}"), } } #[test] +fn test_get_cloned() { + let m = RwLock::new(Cloneable(10)); + + assert_eq!(m.get_cloned().unwrap(), Cloneable(10)); +} + +#[test] +fn test_get_cloned_poison() { + let m = new_poisoned_rwlock(Cloneable(10)); + + match m.get_cloned() { + Err(e) => assert_eq!(e.into_inner(), ()), + Ok(x) => panic!("get of poisoned RwLock is Ok: {x:?}"), + } +} + +#[test] fn test_get_mut() { let mut m = RwLock::new(NonCopy(10)); *m.get_mut().unwrap() = NonCopy(20); @@ -305,22 +351,91 @@ fn test_get_mut() { #[test] fn test_get_mut_poison() { - let m = Arc::new(RwLock::new(NonCopy(10))); - let m2 = m.clone(); - let _ = thread::spawn(move || { - let _lock = m2.write().unwrap(); - panic!("test panic in inner thread to poison RwLock"); - }) - .join(); + let mut m = new_poisoned_rwlock(NonCopy(10)); - assert!(m.is_poisoned()); - match Arc::try_unwrap(m).unwrap().get_mut() { + match m.get_mut() { Err(e) => assert_eq!(*e.into_inner(), NonCopy(10)), Ok(x) => panic!("get_mut of poisoned RwLock is Ok: {x:?}"), } } #[test] +fn test_set() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = RwLock::new(init()); + + assert_eq!(*m.read().unwrap(), init()); + m.set(value()).unwrap(); + assert_eq!(*m.read().unwrap(), value()); + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] +fn test_set_poison() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = new_poisoned_rwlock(init()); + + match m.set(value()) { + Err(e) => { + assert_eq!(e.into_inner(), value()); + assert_eq!(m.into_inner().unwrap_err().into_inner(), init()); + } + Ok(x) => panic!("set of poisoned RwLock is Ok: {x:?}"), + } + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] +fn test_replace() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = RwLock::new(init()); + + assert_eq!(*m.read().unwrap(), init()); + assert_eq!(m.replace(value()).unwrap(), init()); + assert_eq!(*m.read().unwrap(), value()); + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] +fn test_replace_poison() { + fn inner<T>(mut init: impl FnMut() -> T, mut value: impl FnMut() -> T) + where + T: Debug + Eq, + { + let m = new_poisoned_rwlock(init()); + + match m.replace(value()) { + Err(e) => { + assert_eq!(e.into_inner(), value()); + assert_eq!(m.into_inner().unwrap_err().into_inner(), init()); + } + Ok(x) => panic!("replace of poisoned RwLock is Ok: {x:?}"), + } + } + + inner(|| NonCopy(10), || NonCopy(20)); + inner(|| NonCopyNeedsDrop(10), || NonCopyNeedsDrop(20)); +} + +#[test] fn test_read_guard_covariance() { fn do_stuff<'a>(_: RwLockReadGuard<'_, &'a i32>, _: &'a i32) {} let j: i32 = 5; @@ -370,7 +485,7 @@ fn test_mapping_mapped_guard() { fn panic_while_mapping_read_unlocked_no_poison() { let lock = RwLock::new(()); - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.read().unwrap(); let _guard = RwLockReadGuard::map::<(), _>(guard, |_| panic!()); }); @@ -385,7 +500,7 @@ fn panic_while_mapping_read_unlocked_no_poison() { } } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.read().unwrap(); let _guard = RwLockReadGuard::try_map::<(), _>(guard, |_| panic!()); }); @@ -400,7 +515,7 @@ fn panic_while_mapping_read_unlocked_no_poison() { } } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.read().unwrap(); let guard = RwLockReadGuard::map::<(), _>(guard, |val| val); let _guard = MappedRwLockReadGuard::map::<(), _>(guard, |_| panic!()); @@ -416,7 +531,7 @@ fn panic_while_mapping_read_unlocked_no_poison() { } } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.read().unwrap(); let guard = RwLockReadGuard::map::<(), _>(guard, |val| val); let _guard = MappedRwLockReadGuard::try_map::<(), _>(guard, |_| panic!()); @@ -439,7 +554,7 @@ fn panic_while_mapping_read_unlocked_no_poison() { fn panic_while_mapping_write_unlocked_poison() { let lock = RwLock::new(()); - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.write().unwrap(); let _guard = RwLockWriteGuard::map::<(), _>(guard, |_| panic!()); }); @@ -452,7 +567,7 @@ fn panic_while_mapping_write_unlocked_poison() { Err(TryLockError::Poisoned(_)) => {} } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.write().unwrap(); let _guard = RwLockWriteGuard::try_map::<(), _>(guard, |_| panic!()); }); @@ -467,7 +582,7 @@ fn panic_while_mapping_write_unlocked_poison() { Err(TryLockError::Poisoned(_)) => {} } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.write().unwrap(); let guard = RwLockWriteGuard::map::<(), _>(guard, |val| val); let _guard = MappedRwLockWriteGuard::map::<(), _>(guard, |_| panic!()); @@ -483,7 +598,7 @@ fn panic_while_mapping_write_unlocked_poison() { Err(TryLockError::Poisoned(_)) => {} } - let _ = crate::panic::catch_unwind(|| { + let _ = panic::catch_unwind(|| { let guard = lock.write().unwrap(); let guard = RwLockWriteGuard::map::<(), _>(guard, |val| val); let _guard = MappedRwLockWriteGuard::try_map::<(), _>(guard, |_| panic!()); diff --git a/library/std/src/sys/pal/unix/net.rs b/library/std/src/sys/pal/unix/net.rs index d140607869c..d73b9fd5eb8 100644 --- a/library/std/src/sys/pal/unix/net.rs +++ b/library/std/src/sys/pal/unix/net.rs @@ -81,6 +81,7 @@ impl Socket { target_os = "netbsd", target_os = "openbsd", target_os = "nto", + target_os = "solaris", ))] { // On platforms that support it we pass the SOCK_CLOEXEC // flag to atomically create the socket and set it as |