diff options
Diffstat (limited to '')
49 files changed, 618 insertions, 870 deletions
diff --git a/library/std/src/sys/common/alloc.rs b/library/std/src/sys/common/alloc.rs index e8e7c51cb..3edbe7280 100644 --- a/library/std/src/sys/common/alloc.rs +++ b/library/std/src/sys/common/alloc.rs @@ -4,7 +4,7 @@ use crate::ptr; // The minimum alignment guaranteed by the architecture. This value is used to // add fast paths for low alignment values. -#[cfg(all(any( +#[cfg(any( target_arch = "x86", target_arch = "arm", target_arch = "mips", @@ -16,9 +16,9 @@ use crate::ptr; target_arch = "hexagon", all(target_arch = "riscv32", not(target_os = "espidf")), all(target_arch = "xtensa", not(target_os = "espidf")), -)))] +))] pub const MIN_ALIGN: usize = 8; -#[cfg(all(any( +#[cfg(any( target_arch = "x86_64", target_arch = "aarch64", target_arch = "mips64", @@ -26,13 +26,13 @@ pub const MIN_ALIGN: usize = 8; target_arch = "sparc64", target_arch = "riscv64", target_arch = "wasm64", -)))] +))] pub const MIN_ALIGN: usize = 16; // The allocator on the esp-idf platform guarantees 4 byte alignment. -#[cfg(all(any( +#[cfg(any( all(target_arch = "riscv32", target_os = "espidf"), all(target_arch = "xtensa", target_os = "espidf"), -)))] +))] pub const MIN_ALIGN: usize = 4; pub unsafe fn realloc_fallback( diff --git a/library/std/src/sys/hermit/fs.rs b/library/std/src/sys/hermit/fs.rs index af297ff1e..6fb92c037 100644 --- a/library/std/src/sys/hermit/fs.rs +++ b/library/std/src/sys/hermit/fs.rs @@ -1,10 +1,8 @@ -use crate::convert::TryFrom; -use crate::ffi::{CStr, CString, OsString}; +use crate::ffi::{CStr, OsString}; use crate::fmt; use crate::hash::{Hash, Hasher}; use crate::io::{self, Error, ErrorKind}; use crate::io::{BorrowedCursor, IoSlice, IoSliceMut, SeekFrom}; -use crate::os::unix::ffi::OsStrExt; use crate::path::{Path, PathBuf}; use crate::sys::common::small_c_string::run_path_with_cstr; use crate::sys::cvt; diff --git a/library/std/src/sys/hermit/mod.rs b/library/std/src/sys/hermit/mod.rs index e6534df89..6811fadb0 100644 --- a/library/std/src/sys/hermit/mod.rs +++ b/library/std/src/sys/hermit/mod.rs @@ -51,9 +51,9 @@ pub mod locks { mod futex_condvar; mod futex_mutex; mod futex_rwlock; - pub(crate) use futex_condvar::MovableCondvar; - pub(crate) use futex_mutex::{MovableMutex, Mutex}; - pub(crate) use futex_rwlock::{MovableRwLock, RwLock}; + pub(crate) use futex_condvar::Condvar; + pub(crate) use futex_mutex::Mutex; + pub(crate) use futex_rwlock::RwLock; } use crate::io::ErrorKind; diff --git a/library/std/src/sys/hermit/thread.rs b/library/std/src/sys/hermit/thread.rs index e53a1fea6..8f65544a9 100644 --- a/library/std/src/sys/hermit/thread.rs +++ b/library/std/src/sys/hermit/thread.rs @@ -5,6 +5,7 @@ use crate::ffi::CStr; use crate::io; use crate::mem; use crate::num::NonZeroUsize; +use crate::ptr; use crate::sys::hermit::abi; use crate::sys::hermit::thread_local_dtor::run_dtors; use crate::time::Duration; @@ -47,7 +48,7 @@ impl Thread { extern "C" fn thread_start(main: usize) { unsafe { // Finally, let's run some code. - Box::from_raw(main as *mut Box<dyn FnOnce()>)(); + Box::from_raw(ptr::from_exposed_addr::<Box<dyn FnOnce()>>(main).cast_mut())(); // run all destructors run_dtors(); diff --git a/library/std/src/sys/itron/condvar.rs b/library/std/src/sys/itron/condvar.rs index 008cd8fb1..7a47cc669 100644 --- a/library/std/src/sys/itron/condvar.rs +++ b/library/std/src/sys/itron/condvar.rs @@ -12,18 +12,13 @@ pub struct Condvar { unsafe impl Send for Condvar {} unsafe impl Sync for Condvar {} -pub type MovableCondvar = Condvar; - impl Condvar { #[inline] pub const fn new() -> Condvar { Condvar { waiters: SpinMutex::new(waiter_queue::WaiterQueue::new()) } } - #[inline] - pub unsafe fn init(&mut self) {} - - pub unsafe fn notify_one(&self) { + pub fn notify_one(&self) { self.waiters.with_locked(|waiters| { if let Some(task) = waiters.pop_front() { // Unpark the task @@ -39,7 +34,7 @@ impl Condvar { }); } - pub unsafe fn notify_all(&self) { + pub fn notify_all(&self) { self.waiters.with_locked(|waiters| { while let Some(task) = waiters.pop_front() { // Unpark the task @@ -76,7 +71,7 @@ impl Condvar { } } - unsafe { mutex.lock() }; + mutex.lock(); } pub unsafe fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool { @@ -114,7 +109,7 @@ impl Condvar { // we woke up because of `notify_*`. let success = self.waiters.with_locked(|waiters| unsafe { !waiters.remove(waiter) }); - unsafe { mutex.lock() }; + mutex.lock(); success } } diff --git a/library/std/src/sys/itron/mutex.rs b/library/std/src/sys/itron/mutex.rs index 085662e6d..1f6cc4194 100644 --- a/library/std/src/sys/itron/mutex.rs +++ b/library/std/src/sys/itron/mutex.rs @@ -11,8 +11,6 @@ pub struct Mutex { mtx: SpinIdOnceCell<()>, } -pub type MovableMutex = Mutex; - /// Create a mutex object. This function never panics. fn new_mtx() -> Result<abi::ID, ItronError> { ItronError::err_if_negative(unsafe { @@ -39,7 +37,7 @@ impl Mutex { } } - pub unsafe fn lock(&self) { + pub fn lock(&self) { let mtx = self.raw(); expect_success(unsafe { abi::loc_mtx(mtx) }, &"loc_mtx"); } @@ -49,7 +47,7 @@ impl Mutex { expect_success_aborting(unsafe { abi::unl_mtx(mtx) }, &"unl_mtx"); } - pub unsafe fn try_lock(&self) -> bool { + pub fn try_lock(&self) -> bool { let mtx = self.raw(); match unsafe { abi::ploc_mtx(mtx) } { abi::E_TMOUT => false, @@ -74,7 +72,7 @@ pub(super) struct MutexGuard<'a>(&'a Mutex); impl<'a> MutexGuard<'a> { #[inline] pub(super) fn lock(x: &'a Mutex) -> Self { - unsafe { x.lock() }; + x.lock(); Self(x) } } diff --git a/library/std/src/sys/itron/thread.rs b/library/std/src/sys/itron/thread.rs index d28f57f33..c2b366808 100644 --- a/library/std/src/sys/itron/thread.rs +++ b/library/std/src/sys/itron/thread.rs @@ -11,18 +11,25 @@ use crate::{ ffi::CStr, hint, io, mem::ManuallyDrop, + ptr::NonNull, sync::atomic::{AtomicUsize, Ordering}, sys::thread_local_dtor::run_dtors, time::Duration, }; pub struct Thread { - inner: ManuallyDrop<Box<ThreadInner>>, + p_inner: NonNull<ThreadInner>, /// The ID of the underlying task. task: abi::ID, } +// Safety: There's nothing in `Thread` that ties it to the original creator. It +// can be dropped by any threads. +unsafe impl Send for Thread {} +// Safety: `Thread` provides no methods that take `&self`. +unsafe impl Sync for Thread {} + /// State data shared between a parent thread and child thread. It's dropped on /// a transition to one of the final states. struct ThreadInner { @@ -90,8 +97,9 @@ impl Thread { }); unsafe extern "C" fn trampoline(exinf: isize) { + let p_inner: *mut ThreadInner = crate::ptr::from_exposed_addr_mut(exinf as usize); // Safety: `ThreadInner` is alive at this point - let inner = unsafe { &*(exinf as *const ThreadInner) }; + let inner = unsafe { &*p_inner }; // Safety: Since `trampoline` is called only once for each // `ThreadInner` and only `trampoline` touches `start`, @@ -119,13 +127,13 @@ impl Thread { // No one will ever join, so we'll ask the collector task to // delete the task. - // In this case, `inner`'s ownership has been moved to us, - // And we are responsible for dropping it. The acquire + // In this case, `*p_inner`'s ownership has been moved to + // us, and we are responsible for dropping it. The acquire // ordering is not necessary because the parent thread made // no memory access needing synchronization since the call // to `acre_tsk`. // Safety: See above. - let _ = unsafe { Box::from_raw(inner as *const _ as *mut ThreadInner) }; + let _ = unsafe { Box::from_raw(p_inner) }; // Safety: There are no pinned references to the stack unsafe { terminate_and_delete_current_task() }; @@ -162,13 +170,14 @@ impl Thread { } } - let inner_ptr = (&*inner) as *const ThreadInner; + // Safety: `Box::into_raw` returns a non-null pointer + let p_inner = unsafe { NonNull::new_unchecked(Box::into_raw(inner)) }; let new_task = ItronError::err_if_negative(unsafe { abi::acre_tsk(&abi::T_CTSK { // Activate this task immediately tskatr: abi::TA_ACT, - exinf: inner_ptr as abi::EXINF, + exinf: p_inner.as_ptr().expose_addr() as abi::EXINF, // The entry point task: Some(trampoline), // Inherit the calling task's base priority @@ -180,7 +189,7 @@ impl Thread { }) .map_err(|e| e.as_io_error())?; - Ok(Self { inner: ManuallyDrop::new(inner), task: new_task }) + Ok(Self { p_inner, task: new_task }) } pub fn yield_now() { @@ -197,8 +206,9 @@ impl Thread { } } - pub fn join(mut self) { - let inner = &*self.inner; + pub fn join(self) { + // Safety: `ThreadInner` is alive at this point + let inner = unsafe { self.p_inner.as_ref() }; // Get the current task ID. Panicking here would cause a resource leak, // so just abort on failure. let current_task = task::current_task_id_aborting(); @@ -243,8 +253,8 @@ impl Thread { unsafe { terminate_and_delete_task(self.task) }; // In either case, we are responsible for dropping `inner`. - // Safety: The contents of `self.inner` will not be accessed hereafter - let _inner = unsafe { ManuallyDrop::take(&mut self.inner) }; + // Safety: The contents of `*p_inner` will not be accessed hereafter + let _inner = unsafe { Box::from_raw(self.p_inner.as_ptr()) }; // Skip the destructor (because it would attempt to detach the thread) crate::mem::forget(self); @@ -253,13 +263,16 @@ impl Thread { impl Drop for Thread { fn drop(&mut self) { + // Safety: `ThreadInner` is alive at this point + let inner = unsafe { self.p_inner.as_ref() }; + // Detach the thread. - match self.inner.lifecycle.swap(LIFECYCLE_DETACHED_OR_JOINED, Ordering::Acquire) { + match inner.lifecycle.swap(LIFECYCLE_DETACHED_OR_JOINED, Ordering::Acquire) { LIFECYCLE_INIT => { // [INIT → DETACHED] // When the time comes, the child will figure out that no // one will ever join it. - // The ownership of `self.inner` is moved to the child thread. + // The ownership of `*p_inner` is moved to the child thread. // However, the release ordering is not necessary because we // made no memory access needing synchronization since the call // to `acre_tsk`. @@ -278,10 +291,9 @@ impl Drop for Thread { // delete by entering the `FINISHED` state. unsafe { terminate_and_delete_task(self.task) }; - // Wwe are responsible for dropping `inner`. - // Safety: The contents of `self.inner` will not be accessed - // hereafter - unsafe { ManuallyDrop::drop(&mut self.inner) }; + // Wwe are responsible for dropping `*p_inner`. + // Safety: The contents of `*p_inner` will not be accessed hereafter + let _ = unsafe { Box::from_raw(self.p_inner.as_ptr()) }; } _ => unsafe { hint::unreachable_unchecked() }, } diff --git a/library/std/src/sys/sgx/condvar.rs b/library/std/src/sys/sgx/condvar.rs index 36534e0ef..aa1174664 100644 --- a/library/std/src/sys/sgx/condvar.rs +++ b/library/std/src/sys/sgx/condvar.rs @@ -4,42 +4,43 @@ use crate::time::Duration; use super::waitqueue::{SpinMutex, WaitQueue, WaitVariable}; +/// FIXME: `UnsafeList` is not movable. +struct AllocatedCondvar(SpinMutex<WaitVariable<()>>); + pub struct Condvar { - inner: SpinMutex<WaitVariable<()>>, + inner: LazyBox<AllocatedCondvar>, } -pub(crate) type MovableCondvar = LazyBox<Condvar>; - -impl LazyInit for Condvar { +impl LazyInit for AllocatedCondvar { fn init() -> Box<Self> { - Box::new(Self::new()) + Box::new(AllocatedCondvar(SpinMutex::new(WaitVariable::new(())))) } } impl Condvar { pub const fn new() -> Condvar { - Condvar { inner: SpinMutex::new(WaitVariable::new(())) } + Condvar { inner: LazyBox::new() } } #[inline] - pub unsafe fn notify_one(&self) { - let _ = WaitQueue::notify_one(self.inner.lock()); + pub fn notify_one(&self) { + let _ = WaitQueue::notify_one(self.inner.0.lock()); } #[inline] - pub unsafe fn notify_all(&self) { - let _ = WaitQueue::notify_all(self.inner.lock()); + pub fn notify_all(&self) { + let _ = WaitQueue::notify_all(self.inner.0.lock()); } pub unsafe fn wait(&self, mutex: &Mutex) { - let guard = self.inner.lock(); + let guard = self.inner.0.lock(); WaitQueue::wait(guard, || unsafe { mutex.unlock() }); - unsafe { mutex.lock() } + mutex.lock() } pub unsafe fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool { - let success = WaitQueue::wait_timeout(&self.inner, dur, || unsafe { mutex.unlock() }); - unsafe { mutex.lock() }; + let success = WaitQueue::wait_timeout(&self.inner.0, dur, || unsafe { mutex.unlock() }); + mutex.lock(); success } } diff --git a/library/std/src/sys/sgx/mod.rs b/library/std/src/sys/sgx/mod.rs index b1d32929e..01e4ffe3d 100644 --- a/library/std/src/sys/sgx/mod.rs +++ b/library/std/src/sys/sgx/mod.rs @@ -3,6 +3,7 @@ //! This module contains the facade (aka platform-specific) implementations of //! OS level functionality for Fortanix SGX. #![deny(unsafe_op_in_unsafe_fn)] +#![allow(fuzzy_provenance_casts)] // FIXME: this entire module systematically confuses pointers and integers use crate::io::ErrorKind; use crate::sync::atomic::{AtomicBool, Ordering}; diff --git a/library/std/src/sys/sgx/mutex.rs b/library/std/src/sys/sgx/mutex.rs index aa747d56b..0dbf020eb 100644 --- a/library/std/src/sys/sgx/mutex.rs +++ b/library/std/src/sys/sgx/mutex.rs @@ -1,28 +1,28 @@ use super::waitqueue::{try_lock_or_false, SpinMutex, WaitQueue, WaitVariable}; use crate::sys_common::lazy_box::{LazyBox, LazyInit}; +/// FIXME: `UnsafeList` is not movable. +struct AllocatedMutex(SpinMutex<WaitVariable<bool>>); + pub struct Mutex { - inner: SpinMutex<WaitVariable<bool>>, + inner: LazyBox<AllocatedMutex>, } -// not movable: see UnsafeList implementation -pub(crate) type MovableMutex = LazyBox<Mutex>; - -impl LazyInit for Mutex { +impl LazyInit for AllocatedMutex { fn init() -> Box<Self> { - Box::new(Self::new()) + Box::new(AllocatedMutex(SpinMutex::new(WaitVariable::new(false)))) } } // Implementation according to “Operating Systems: Three Easy Pieces”, chapter 28 impl Mutex { pub const fn new() -> Mutex { - Mutex { inner: SpinMutex::new(WaitVariable::new(false)) } + Mutex { inner: LazyBox::new() } } #[inline] - pub unsafe fn lock(&self) { - let mut guard = self.inner.lock(); + pub fn lock(&self) { + let mut guard = self.inner.0.lock(); if *guard.lock_var() { // Another thread has the lock, wait WaitQueue::wait(guard, || {}) @@ -35,7 +35,7 @@ impl Mutex { #[inline] pub unsafe fn unlock(&self) { - let guard = self.inner.lock(); + let guard = self.inner.0.lock(); if let Err(mut guard) = WaitQueue::notify_one(guard) { // No other waiters, unlock *guard.lock_var_mut() = false; @@ -45,8 +45,8 @@ impl Mutex { } #[inline] - pub unsafe fn try_lock(&self) -> bool { - let mut guard = try_lock_or_false!(self.inner); + pub fn try_lock(&self) -> bool { + let mut guard = try_lock_or_false!(self.inner.0); if *guard.lock_var() { // Another thread has the lock false diff --git a/library/std/src/sys/sgx/rwlock.rs b/library/std/src/sys/sgx/rwlock.rs index a97fb9ab0..d89de18ca 100644 --- a/library/std/src/sys/sgx/rwlock.rs +++ b/library/std/src/sys/sgx/rwlock.rs @@ -7,42 +7,45 @@ use crate::sys_common::lazy_box::{LazyBox, LazyInit}; use super::waitqueue::{ try_lock_or_false, NotifiedTcs, SpinMutex, SpinMutexGuard, WaitQueue, WaitVariable, }; -use crate::mem; +use crate::alloc::Layout; -pub struct RwLock { +struct AllocatedRwLock { readers: SpinMutex<WaitVariable<Option<NonZeroUsize>>>, writer: SpinMutex<WaitVariable<bool>>, } -pub(crate) type MovableRwLock = LazyBox<RwLock>; +pub struct RwLock { + inner: LazyBox<AllocatedRwLock>, +} -impl LazyInit for RwLock { +impl LazyInit for AllocatedRwLock { fn init() -> Box<Self> { - Box::new(Self::new()) + Box::new(AllocatedRwLock { + readers: SpinMutex::new(WaitVariable::new(None)), + writer: SpinMutex::new(WaitVariable::new(false)), + }) } } -// Check at compile time that RwLock size matches C definition (see test_c_rwlock_initializer below) -// -// # Safety -// Never called, as it is a compile time check. -#[allow(dead_code)] -unsafe fn rw_lock_size_assert(r: RwLock) { - unsafe { mem::transmute::<RwLock, [u8; 144]>(r) }; -} +// Check at compile time that RwLock's size and alignment matches the C definition +// in libunwind (see also `test_c_rwlock_initializer` in `tests`). +const _: () = { + let rust = Layout::new::<RwLock>(); + let c = Layout::new::<*mut ()>(); + assert!(rust.size() == c.size()); + assert!(rust.align() == c.align()); +}; impl RwLock { pub const fn new() -> RwLock { - RwLock { - readers: SpinMutex::new(WaitVariable::new(None)), - writer: SpinMutex::new(WaitVariable::new(false)), - } + RwLock { inner: LazyBox::new() } } #[inline] - pub unsafe fn read(&self) { - let mut rguard = self.readers.lock(); - let wguard = self.writer.lock(); + pub fn read(&self) { + let lock = &*self.inner; + let mut rguard = lock.readers.lock(); + let wguard = lock.writer.lock(); if *wguard.lock_var() || !wguard.queue_empty() { // Another thread has or is waiting for the write lock, wait drop(wguard); @@ -57,8 +60,9 @@ impl RwLock { #[inline] pub unsafe fn try_read(&self) -> bool { - let mut rguard = try_lock_or_false!(self.readers); - let wguard = try_lock_or_false!(self.writer); + let lock = &*self.inner; + let mut rguard = try_lock_or_false!(lock.readers); + let wguard = try_lock_or_false!(lock.writer); if *wguard.lock_var() || !wguard.queue_empty() { // Another thread has or is waiting for the write lock false @@ -71,9 +75,10 @@ impl RwLock { } #[inline] - pub unsafe fn write(&self) { - let rguard = self.readers.lock(); - let mut wguard = self.writer.lock(); + pub fn write(&self) { + let lock = &*self.inner; + let rguard = lock.readers.lock(); + let mut wguard = lock.writer.lock(); if *wguard.lock_var() || rguard.lock_var().is_some() { // Another thread has the lock, wait drop(rguard); @@ -86,9 +91,10 @@ impl RwLock { } #[inline] - pub unsafe fn try_write(&self) -> bool { - let rguard = try_lock_or_false!(self.readers); - let mut wguard = try_lock_or_false!(self.writer); + pub fn try_write(&self) -> bool { + let lock = &*self.inner; + let rguard = try_lock_or_false!(lock.readers); + let mut wguard = try_lock_or_false!(lock.writer); if *wguard.lock_var() || rguard.lock_var().is_some() { // Another thread has the lock false @@ -122,8 +128,9 @@ impl RwLock { #[inline] pub unsafe fn read_unlock(&self) { - let rguard = self.readers.lock(); - let wguard = self.writer.lock(); + let lock = &*self.inner; + let rguard = lock.readers.lock(); + let wguard = lock.writer.lock(); unsafe { self.__read_unlock(rguard, wguard) }; } @@ -158,8 +165,9 @@ impl RwLock { #[inline] pub unsafe fn write_unlock(&self) { - let rguard = self.readers.lock(); - let wguard = self.writer.lock(); + let lock = &*self.inner; + let rguard = lock.readers.lock(); + let wguard = lock.writer.lock(); unsafe { self.__write_unlock(rguard, wguard) }; } @@ -167,8 +175,9 @@ impl RwLock { #[inline] #[cfg_attr(test, allow(dead_code))] unsafe fn unlock(&self) { - let rguard = self.readers.lock(); - let wguard = self.writer.lock(); + let lock = &*self.inner; + let rguard = lock.readers.lock(); + let wguard = lock.writer.lock(); if *wguard.lock_var() == true { unsafe { self.__write_unlock(rguard, wguard) }; } else { @@ -201,6 +210,7 @@ pub unsafe extern "C" fn __rust_rwlock_wrlock(p: *mut RwLock) -> i32 { unsafe { (*p).write() }; return 0; } + #[cfg(not(test))] #[no_mangle] pub unsafe extern "C" fn __rust_rwlock_unlock(p: *mut RwLock) -> i32 { diff --git a/library/std/src/sys/sgx/rwlock/tests.rs b/library/std/src/sys/sgx/rwlock/tests.rs index 479996115..5fd6670af 100644 --- a/library/std/src/sys/sgx/rwlock/tests.rs +++ b/library/std/src/sys/sgx/rwlock/tests.rs @@ -1,22 +1,12 @@ use super::*; +use crate::ptr; // Verify that the byte pattern libunwind uses to initialize an RwLock is // equivalent to the value of RwLock::new(). If the value changes, // `src/UnwindRustSgx.h` in libunwind needs to be changed too. #[test] fn test_c_rwlock_initializer() { - #[rustfmt::skip] - const C_RWLOCK_INIT: &[u8] = &[ - /* 0x00 */ 0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x10 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x20 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x30 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x40 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x50 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x60 */ 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x70 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - /* 0x80 */ 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, - ]; + const C_RWLOCK_INIT: *mut () = ptr::null_mut(); // For the test to work, we need the padding/unused bytes in RwLock to be // initialized as 0. In practice, this is the case with statics. @@ -26,6 +16,6 @@ fn test_c_rwlock_initializer() { // If the assertion fails, that not necessarily an issue with the value // of C_RWLOCK_INIT. It might just be an issue with the way padding // bytes are initialized in the test code. - assert_eq!(&crate::mem::transmute_copy::<_, [u8; 144]>(&RUST_RWLOCK_INIT), C_RWLOCK_INIT); + assert_eq!(crate::mem::transmute_copy::<_, *mut ()>(&RUST_RWLOCK_INIT), C_RWLOCK_INIT); }; } diff --git a/library/std/src/sys/solid/io.rs b/library/std/src/sys/solid/io.rs index 9eb17a10d..a862bb787 100644 --- a/library/std/src/sys/solid/io.rs +++ b/library/std/src/sys/solid/io.rs @@ -75,3 +75,7 @@ impl<'a> IoSliceMut<'a> { unsafe { slice::from_raw_parts_mut(self.vec.iov_base as *mut u8, self.vec.iov_len) } } } + +pub fn is_terminal<T>(_: &T) -> bool { + false +} diff --git a/library/std/src/sys/solid/os.rs b/library/std/src/sys/solid/os.rs index 4906c6268..6135921f0 100644 --- a/library/std/src/sys/solid/os.rs +++ b/library/std/src/sys/solid/os.rs @@ -1,7 +1,6 @@ use super::unsupported; -use crate::convert::TryFrom; use crate::error::Error as StdError; -use crate::ffi::{CStr, CString, OsStr, OsString}; +use crate::ffi::{CStr, OsStr, OsString}; use crate::fmt; use crate::io; use crate::os::{ diff --git a/library/std/src/sys/solid/rwlock.rs b/library/std/src/sys/solid/rwlock.rs index 0a770cf03..ecb4eb83b 100644 --- a/library/std/src/sys/solid/rwlock.rs +++ b/library/std/src/sys/solid/rwlock.rs @@ -12,8 +12,6 @@ pub struct RwLock { rwl: SpinIdOnceCell<()>, } -pub type MovableRwLock = RwLock; - // Safety: `num_readers` is protected by `mtx_num_readers` unsafe impl Send for RwLock {} unsafe impl Sync for RwLock {} @@ -37,13 +35,13 @@ impl RwLock { } #[inline] - pub unsafe fn read(&self) { + pub fn read(&self) { let rwl = self.raw(); expect_success(unsafe { abi::rwl_loc_rdl(rwl) }, &"rwl_loc_rdl"); } #[inline] - pub unsafe fn try_read(&self) -> bool { + pub fn try_read(&self) -> bool { let rwl = self.raw(); match unsafe { abi::rwl_ploc_rdl(rwl) } { abi::E_TMOUT => false, @@ -55,13 +53,13 @@ impl RwLock { } #[inline] - pub unsafe fn write(&self) { + pub fn write(&self) { let rwl = self.raw(); expect_success(unsafe { abi::rwl_loc_wrl(rwl) }, &"rwl_loc_wrl"); } #[inline] - pub unsafe fn try_write(&self) -> bool { + pub fn try_write(&self) -> bool { let rwl = self.raw(); match unsafe { abi::rwl_ploc_wrl(rwl) } { abi::E_TMOUT => false, diff --git a/library/std/src/sys/unix/locks/fuchsia_mutex.rs b/library/std/src/sys/unix/locks/fuchsia_mutex.rs index 117611ce4..5d89e5a13 100644 --- a/library/std/src/sys/unix/locks/fuchsia_mutex.rs +++ b/library/std/src/sys/unix/locks/fuchsia_mutex.rs @@ -53,8 +53,6 @@ const CONTESTED_BIT: u32 = 1; // This can never be a valid `zx_handle_t`. const UNLOCKED: u32 = 0; -pub type MovableMutex = Mutex; - pub struct Mutex { futex: AtomicU32, } @@ -86,23 +84,27 @@ impl Mutex { } #[inline] - pub unsafe fn try_lock(&self) -> bool { - let thread_self = zx_thread_self(); + pub fn try_lock(&self) -> bool { + let thread_self = unsafe { zx_thread_self() }; self.futex.compare_exchange(UNLOCKED, to_state(thread_self), Acquire, Relaxed).is_ok() } #[inline] - pub unsafe fn lock(&self) { - let thread_self = zx_thread_self(); + pub fn lock(&self) { + let thread_self = unsafe { zx_thread_self() }; if let Err(state) = self.futex.compare_exchange(UNLOCKED, to_state(thread_self), Acquire, Relaxed) { - self.lock_contested(state, thread_self); + unsafe { + self.lock_contested(state, thread_self); + } } } + /// # Safety + /// `thread_self` must be the handle for the current thread. #[cold] - fn lock_contested(&self, mut state: u32, thread_self: zx_handle_t) { + unsafe fn lock_contested(&self, mut state: u32, thread_self: zx_handle_t) { let owned_state = mark_contested(to_state(thread_self)); loop { // Mark the mutex as contested if it is not already. diff --git a/library/std/src/sys/unix/locks/futex_condvar.rs b/library/std/src/sys/unix/locks/futex_condvar.rs index c0576c178..4bd65dd25 100644 --- a/library/std/src/sys/unix/locks/futex_condvar.rs +++ b/library/std/src/sys/unix/locks/futex_condvar.rs @@ -3,8 +3,6 @@ use crate::sync::atomic::{AtomicU32, Ordering::Relaxed}; use crate::sys::futex::{futex_wait, futex_wake, futex_wake_all}; use crate::time::Duration; -pub type MovableCondvar = Condvar; - pub struct Condvar { // The value of this atomic is simply incremented on every notification. // This is used by `.wait()` to not miss any notifications after @@ -21,12 +19,12 @@ impl Condvar { // All the memory orderings here are `Relaxed`, // because synchronization is done by unlocking and locking the mutex. - pub unsafe fn notify_one(&self) { + pub fn notify_one(&self) { self.futex.fetch_add(1, Relaxed); futex_wake(&self.futex); } - pub unsafe fn notify_all(&self) { + pub fn notify_all(&self) { self.futex.fetch_add(1, Relaxed); futex_wake_all(&self.futex); } diff --git a/library/std/src/sys/unix/locks/futex_mutex.rs b/library/std/src/sys/unix/locks/futex_mutex.rs index 33b13dad4..c01229586 100644 --- a/library/std/src/sys/unix/locks/futex_mutex.rs +++ b/library/std/src/sys/unix/locks/futex_mutex.rs @@ -4,8 +4,6 @@ use crate::sync::atomic::{ }; use crate::sys::futex::{futex_wait, futex_wake}; -pub type MovableMutex = Mutex; - pub struct Mutex { /// 0: unlocked /// 1: locked, no other threads waiting @@ -20,12 +18,12 @@ impl Mutex { } #[inline] - pub unsafe fn try_lock(&self) -> bool { + pub fn try_lock(&self) -> bool { self.futex.compare_exchange(0, 1, Acquire, Relaxed).is_ok() } #[inline] - pub unsafe fn lock(&self) { + pub fn lock(&self) { if self.futex.compare_exchange(0, 1, Acquire, Relaxed).is_err() { self.lock_contended(); } diff --git a/library/std/src/sys/unix/locks/futex_rwlock.rs b/library/std/src/sys/unix/locks/futex_rwlock.rs index 0cc92244e..aa0de9002 100644 --- a/library/std/src/sys/unix/locks/futex_rwlock.rs +++ b/library/std/src/sys/unix/locks/futex_rwlock.rs @@ -4,8 +4,6 @@ use crate::sync::atomic::{ }; use crate::sys::futex::{futex_wait, futex_wake, futex_wake_all}; -pub type MovableRwLock = RwLock; - pub struct RwLock { // The state consists of a 30-bit reader counter, a 'readers waiting' flag, and a 'writers waiting' flag. // Bits 0..30: @@ -70,14 +68,14 @@ impl RwLock { } #[inline] - pub unsafe fn try_read(&self) -> bool { + pub fn try_read(&self) -> bool { self.state .fetch_update(Acquire, Relaxed, |s| is_read_lockable(s).then(|| s + READ_LOCKED)) .is_ok() } #[inline] - pub unsafe fn read(&self) { + pub fn read(&self) { let state = self.state.load(Relaxed); if !is_read_lockable(state) || self @@ -144,14 +142,14 @@ impl RwLock { } #[inline] - pub unsafe fn try_write(&self) -> bool { + pub fn try_write(&self) -> bool { self.state .fetch_update(Acquire, Relaxed, |s| is_unlocked(s).then(|| s + WRITE_LOCKED)) .is_ok() } #[inline] - pub unsafe fn write(&self) { + pub fn write(&self) { if self.state.compare_exchange_weak(0, WRITE_LOCKED, Acquire, Relaxed).is_err() { self.write_contended(); } diff --git a/library/std/src/sys/unix/locks/mod.rs b/library/std/src/sys/unix/locks/mod.rs index 9bb314b70..b2e0e49ad 100644 --- a/library/std/src/sys/unix/locks/mod.rs +++ b/library/std/src/sys/unix/locks/mod.rs @@ -10,22 +10,22 @@ cfg_if::cfg_if! { mod futex_mutex; mod futex_rwlock; mod futex_condvar; - pub(crate) use futex_mutex::{Mutex, MovableMutex}; - pub(crate) use futex_rwlock::MovableRwLock; - pub(crate) use futex_condvar::MovableCondvar; + pub(crate) use futex_mutex::Mutex; + pub(crate) use futex_rwlock::RwLock; + pub(crate) use futex_condvar::Condvar; } else if #[cfg(target_os = "fuchsia")] { mod fuchsia_mutex; mod futex_rwlock; mod futex_condvar; - pub(crate) use fuchsia_mutex::{Mutex, MovableMutex}; - pub(crate) use futex_rwlock::MovableRwLock; - pub(crate) use futex_condvar::MovableCondvar; + pub(crate) use fuchsia_mutex::Mutex; + pub(crate) use futex_rwlock::RwLock; + pub(crate) use futex_condvar::Condvar; } else { mod pthread_mutex; mod pthread_rwlock; mod pthread_condvar; - pub(crate) use pthread_mutex::{Mutex, MovableMutex}; - pub(crate) use pthread_rwlock::MovableRwLock; - pub(crate) use pthread_condvar::MovableCondvar; + pub(crate) use pthread_mutex::Mutex; + pub(crate) use pthread_rwlock::RwLock; + pub(crate) use pthread_condvar::Condvar; } } diff --git a/library/std/src/sys/unix/locks/pthread_condvar.rs b/library/std/src/sys/unix/locks/pthread_condvar.rs index 4741c0c67..1ddb09905 100644 --- a/library/std/src/sys/unix/locks/pthread_condvar.rs +++ b/library/std/src/sys/unix/locks/pthread_condvar.rs @@ -1,17 +1,17 @@ use crate::cell::UnsafeCell; +use crate::ptr; +use crate::sync::atomic::{AtomicPtr, Ordering::Relaxed}; use crate::sys::locks::{pthread_mutex, Mutex}; use crate::sys_common::lazy_box::{LazyBox, LazyInit}; use crate::time::Duration; +struct AllocatedCondvar(UnsafeCell<libc::pthread_cond_t>); + pub struct Condvar { - inner: UnsafeCell<libc::pthread_cond_t>, + inner: LazyBox<AllocatedCondvar>, + mutex: AtomicPtr<libc::pthread_mutex_t>, } -pub(crate) type MovableCondvar = LazyBox<Condvar>; - -unsafe impl Send for Condvar {} -unsafe impl Sync for Condvar {} - const TIMESPEC_MAX: libc::timespec = libc::timespec { tv_sec: <libc::time_t>::MAX, tv_nsec: 1_000_000_000 - 1 }; @@ -19,81 +19,104 @@ fn saturating_cast_to_time_t(value: u64) -> libc::time_t { if value > <libc::time_t>::MAX as u64 { <libc::time_t>::MAX } else { value as libc::time_t } } -impl LazyInit for Condvar { +#[inline] +fn raw(c: &Condvar) -> *mut libc::pthread_cond_t { + c.inner.0.get() +} + +unsafe impl Send for AllocatedCondvar {} +unsafe impl Sync for AllocatedCondvar {} + +impl LazyInit for AllocatedCondvar { fn init() -> Box<Self> { - let mut condvar = Box::new(Self::new()); - unsafe { condvar.init() }; + let condvar = Box::new(AllocatedCondvar(UnsafeCell::new(libc::PTHREAD_COND_INITIALIZER))); + + cfg_if::cfg_if! { + if #[cfg(any( + target_os = "macos", + target_os = "ios", + target_os = "watchos", + target_os = "l4re", + target_os = "android", + target_os = "redox" + ))] { + // `pthread_condattr_setclock` is unfortunately not supported on these platforms. + } else if #[cfg(any(target_os = "espidf", target_os = "horizon"))] { + // NOTE: ESP-IDF's PTHREAD_COND_INITIALIZER support is not released yet + // So on that platform, init() should always be called + // Moreover, that platform does not have pthread_condattr_setclock support, + // hence that initialization should be skipped as well + // + // Similar story for the 3DS (horizon). + let r = unsafe { libc::pthread_cond_init(condvar.0.get(), crate::ptr::null()) }; + assert_eq!(r, 0); + } else { + use crate::mem::MaybeUninit; + let mut attr = MaybeUninit::<libc::pthread_condattr_t>::uninit(); + let r = unsafe { libc::pthread_condattr_init(attr.as_mut_ptr()) }; + assert_eq!(r, 0); + let r = unsafe { libc::pthread_condattr_setclock(attr.as_mut_ptr(), libc::CLOCK_MONOTONIC) }; + assert_eq!(r, 0); + let r = unsafe { libc::pthread_cond_init(condvar.0.get(), attr.as_ptr()) }; + assert_eq!(r, 0); + let r = unsafe { libc::pthread_condattr_destroy(attr.as_mut_ptr()) }; + assert_eq!(r, 0); + } + } + condvar } } -impl Condvar { - pub const fn new() -> Condvar { - // Might be moved and address is changing it is better to avoid - // initialization of potentially opaque OS data before it landed - Condvar { inner: UnsafeCell::new(libc::PTHREAD_COND_INITIALIZER) } +impl Drop for AllocatedCondvar { + #[inline] + fn drop(&mut self) { + let r = unsafe { libc::pthread_cond_destroy(self.0.get()) }; + if cfg!(target_os = "dragonfly") { + // On DragonFly pthread_cond_destroy() returns EINVAL if called on + // a condvar that was just initialized with + // libc::PTHREAD_COND_INITIALIZER. Once it is used or + // pthread_cond_init() is called, this behaviour no longer occurs. + debug_assert!(r == 0 || r == libc::EINVAL); + } else { + debug_assert_eq!(r, 0); + } } +} - #[cfg(any( - target_os = "macos", - target_os = "ios", - target_os = "watchos", - target_os = "l4re", - target_os = "android", - target_os = "redox" - ))] - unsafe fn init(&mut self) {} - - // NOTE: ESP-IDF's PTHREAD_COND_INITIALIZER support is not released yet - // So on that platform, init() should always be called - // Moreover, that platform does not have pthread_condattr_setclock support, - // hence that initialization should be skipped as well - // - // Similar story for the 3DS (horizon). - #[cfg(any(target_os = "espidf", target_os = "horizon"))] - unsafe fn init(&mut self) { - let r = libc::pthread_cond_init(self.inner.get(), crate::ptr::null()); - assert_eq!(r, 0); +impl Condvar { + pub const fn new() -> Condvar { + Condvar { inner: LazyBox::new(), mutex: AtomicPtr::new(ptr::null_mut()) } } - #[cfg(not(any( - target_os = "macos", - target_os = "ios", - target_os = "watchos", - target_os = "l4re", - target_os = "android", - target_os = "redox", - target_os = "espidf", - target_os = "horizon" - )))] - unsafe fn init(&mut self) { - use crate::mem::MaybeUninit; - let mut attr = MaybeUninit::<libc::pthread_condattr_t>::uninit(); - let r = libc::pthread_condattr_init(attr.as_mut_ptr()); - assert_eq!(r, 0); - let r = libc::pthread_condattr_setclock(attr.as_mut_ptr(), libc::CLOCK_MONOTONIC); - assert_eq!(r, 0); - let r = libc::pthread_cond_init(self.inner.get(), attr.as_ptr()); - assert_eq!(r, 0); - let r = libc::pthread_condattr_destroy(attr.as_mut_ptr()); - assert_eq!(r, 0); + #[inline] + fn verify(&self, mutex: *mut libc::pthread_mutex_t) { + // Relaxed is okay here because we never read through `self.addr`, and only use it to + // compare addresses. + match self.mutex.compare_exchange(ptr::null_mut(), mutex, Relaxed, Relaxed) { + Ok(_) => {} // Stored the address + Err(n) if n == mutex => {} // Lost a race to store the same address + _ => panic!("attempted to use a condition variable with two mutexes"), + } } #[inline] - pub unsafe fn notify_one(&self) { - let r = libc::pthread_cond_signal(self.inner.get()); + pub fn notify_one(&self) { + let r = unsafe { libc::pthread_cond_signal(raw(self)) }; debug_assert_eq!(r, 0); } #[inline] - pub unsafe fn notify_all(&self) { - let r = libc::pthread_cond_broadcast(self.inner.get()); + pub fn notify_all(&self) { + let r = unsafe { libc::pthread_cond_broadcast(raw(self)) }; debug_assert_eq!(r, 0); } #[inline] pub unsafe fn wait(&self, mutex: &Mutex) { - let r = libc::pthread_cond_wait(self.inner.get(), pthread_mutex::raw(mutex)); + let mutex = pthread_mutex::raw(mutex); + self.verify(mutex); + let r = libc::pthread_cond_wait(raw(self), mutex); debug_assert_eq!(r, 0); } @@ -112,6 +135,9 @@ impl Condvar { pub unsafe fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool { use crate::mem; + let mutex = pthread_mutex::raw(mutex); + self.verify(mutex); + let mut now: libc::timespec = mem::zeroed(); let r = libc::clock_gettime(libc::CLOCK_MONOTONIC, &mut now); assert_eq!(r, 0); @@ -127,7 +153,7 @@ impl Condvar { let timeout = sec.map(|s| libc::timespec { tv_sec: s, tv_nsec: nsec as _ }).unwrap_or(TIMESPEC_MAX); - let r = libc::pthread_cond_timedwait(self.inner.get(), pthread_mutex::raw(mutex), &timeout); + let r = libc::pthread_cond_timedwait(raw(self), mutex, &timeout); assert!(r == libc::ETIMEDOUT || r == 0); r == 0 } @@ -144,9 +170,11 @@ impl Condvar { target_os = "horizon" ))] pub unsafe fn wait_timeout(&self, mutex: &Mutex, mut dur: Duration) -> bool { - use crate::ptr; use crate::time::Instant; + let mutex = pthread_mutex::raw(mutex); + self.verify(mutex); + // 1000 years let max_dur = Duration::from_secs(1000 * 365 * 86400); @@ -187,36 +215,11 @@ impl Condvar { .unwrap_or(TIMESPEC_MAX); // And wait! - let r = libc::pthread_cond_timedwait(self.inner.get(), pthread_mutex::raw(mutex), &timeout); + let r = libc::pthread_cond_timedwait(raw(self), mutex, &timeout); debug_assert!(r == libc::ETIMEDOUT || r == 0); // ETIMEDOUT is not a totally reliable method of determining timeout due // to clock shifts, so do the check ourselves stable_now.elapsed() < dur } - - #[inline] - #[cfg(not(target_os = "dragonfly"))] - unsafe fn destroy(&mut self) { - let r = libc::pthread_cond_destroy(self.inner.get()); - debug_assert_eq!(r, 0); - } - - #[inline] - #[cfg(target_os = "dragonfly")] - unsafe fn destroy(&mut self) { - let r = libc::pthread_cond_destroy(self.inner.get()); - // On DragonFly pthread_cond_destroy() returns EINVAL if called on - // a condvar that was just initialized with - // libc::PTHREAD_COND_INITIALIZER. Once it is used or - // pthread_cond_init() is called, this behaviour no longer occurs. - debug_assert!(r == 0 || r == libc::EINVAL); - } -} - -impl Drop for Condvar { - #[inline] - fn drop(&mut self) { - unsafe { self.destroy() }; - } } diff --git a/library/std/src/sys/unix/locks/pthread_mutex.rs b/library/std/src/sys/unix/locks/pthread_mutex.rs index 5964935dd..8a78bc1fd 100644 --- a/library/std/src/sys/unix/locks/pthread_mutex.rs +++ b/library/std/src/sys/unix/locks/pthread_mutex.rs @@ -3,56 +3,24 @@ use crate::mem::{forget, MaybeUninit}; use crate::sys::cvt_nz; use crate::sys_common::lazy_box::{LazyBox, LazyInit}; +struct AllocatedMutex(UnsafeCell<libc::pthread_mutex_t>); + pub struct Mutex { - inner: UnsafeCell<libc::pthread_mutex_t>, + inner: LazyBox<AllocatedMutex>, } -pub(crate) type MovableMutex = LazyBox<Mutex>; - #[inline] pub unsafe fn raw(m: &Mutex) -> *mut libc::pthread_mutex_t { - m.inner.get() + m.inner.0.get() } -unsafe impl Send for Mutex {} -unsafe impl Sync for Mutex {} +unsafe impl Send for AllocatedMutex {} +unsafe impl Sync for AllocatedMutex {} -impl LazyInit for Mutex { +impl LazyInit for AllocatedMutex { fn init() -> Box<Self> { - let mut mutex = Box::new(Self::new()); - unsafe { mutex.init() }; - mutex - } - - fn destroy(mutex: Box<Self>) { - // We're not allowed to pthread_mutex_destroy a locked mutex, - // so check first if it's unlocked. - if unsafe { mutex.try_lock() } { - unsafe { mutex.unlock() }; - drop(mutex); - } else { - // The mutex is locked. This happens if a MutexGuard is leaked. - // In this case, we just leak the Mutex too. - forget(mutex); - } - } - - fn cancel_init(_: Box<Self>) { - // In this case, we can just drop it without any checks, - // since it cannot have been locked yet. - } -} + let mutex = Box::new(AllocatedMutex(UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER))); -impl Mutex { - pub const fn new() -> Mutex { - // Might be moved to a different address, so it is better to avoid - // initialization of potentially opaque OS data before it landed. - // Be very careful using this newly constructed `Mutex`, reentrant - // locking is undefined behavior until `init` is called! - Mutex { inner: UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER) } - } - #[inline] - unsafe fn init(&mut self) { // Issue #33770 // // A pthread mutex initialized with PTHREAD_MUTEX_INITIALIZER will have @@ -77,49 +45,77 @@ impl Mutex { // references, we instead create the mutex with type // PTHREAD_MUTEX_NORMAL which is guaranteed to deadlock if we try to // re-lock it from the same thread, thus avoiding undefined behavior. - let mut attr = MaybeUninit::<libc::pthread_mutexattr_t>::uninit(); - cvt_nz(libc::pthread_mutexattr_init(attr.as_mut_ptr())).unwrap(); - let attr = PthreadMutexAttr(&mut attr); - cvt_nz(libc::pthread_mutexattr_settype(attr.0.as_mut_ptr(), libc::PTHREAD_MUTEX_NORMAL)) + unsafe { + let mut attr = MaybeUninit::<libc::pthread_mutexattr_t>::uninit(); + cvt_nz(libc::pthread_mutexattr_init(attr.as_mut_ptr())).unwrap(); + let attr = PthreadMutexAttr(&mut attr); + cvt_nz(libc::pthread_mutexattr_settype( + attr.0.as_mut_ptr(), + libc::PTHREAD_MUTEX_NORMAL, + )) .unwrap(); - cvt_nz(libc::pthread_mutex_init(self.inner.get(), attr.0.as_ptr())).unwrap(); + cvt_nz(libc::pthread_mutex_init(mutex.0.get(), attr.0.as_ptr())).unwrap(); + } + + mutex } - #[inline] - pub unsafe fn lock(&self) { - let r = libc::pthread_mutex_lock(self.inner.get()); - debug_assert_eq!(r, 0); + + fn destroy(mutex: Box<Self>) { + // We're not allowed to pthread_mutex_destroy a locked mutex, + // so check first if it's unlocked. + if unsafe { libc::pthread_mutex_trylock(mutex.0.get()) == 0 } { + unsafe { libc::pthread_mutex_unlock(mutex.0.get()) }; + drop(mutex); + } else { + // The mutex is locked. This happens if a MutexGuard is leaked. + // In this case, we just leak the Mutex too. + forget(mutex); + } } + + fn cancel_init(_: Box<Self>) { + // In this case, we can just drop it without any checks, + // since it cannot have been locked yet. + } +} + +impl Drop for AllocatedMutex { #[inline] - pub unsafe fn unlock(&self) { - let r = libc::pthread_mutex_unlock(self.inner.get()); - debug_assert_eq!(r, 0); + fn drop(&mut self) { + let r = unsafe { libc::pthread_mutex_destroy(self.0.get()) }; + if cfg!(target_os = "dragonfly") { + // On DragonFly pthread_mutex_destroy() returns EINVAL if called on a + // mutex that was just initialized with libc::PTHREAD_MUTEX_INITIALIZER. + // Once it is used (locked/unlocked) or pthread_mutex_init() is called, + // this behaviour no longer occurs. + debug_assert!(r == 0 || r == libc::EINVAL); + } else { + debug_assert_eq!(r, 0); + } } +} + +impl Mutex { #[inline] - pub unsafe fn try_lock(&self) -> bool { - libc::pthread_mutex_trylock(self.inner.get()) == 0 + pub const fn new() -> Mutex { + Mutex { inner: LazyBox::new() } } + #[inline] - #[cfg(not(target_os = "dragonfly"))] - unsafe fn destroy(&mut self) { - let r = libc::pthread_mutex_destroy(self.inner.get()); + pub unsafe fn lock(&self) { + let r = libc::pthread_mutex_lock(raw(self)); debug_assert_eq!(r, 0); } + #[inline] - #[cfg(target_os = "dragonfly")] - unsafe fn destroy(&mut self) { - let r = libc::pthread_mutex_destroy(self.inner.get()); - // On DragonFly pthread_mutex_destroy() returns EINVAL if called on a - // mutex that was just initialized with libc::PTHREAD_MUTEX_INITIALIZER. - // Once it is used (locked/unlocked) or pthread_mutex_init() is called, - // this behaviour no longer occurs. - debug_assert!(r == 0 || r == libc::EINVAL); + pub unsafe fn unlock(&self) { + let r = libc::pthread_mutex_unlock(raw(self)); + debug_assert_eq!(r, 0); } -} -impl Drop for Mutex { #[inline] - fn drop(&mut self) { - unsafe { self.destroy() }; + pub unsafe fn try_lock(&self) -> bool { + libc::pthread_mutex_trylock(raw(self)) == 0 } } diff --git a/library/std/src/sys/unix/locks/pthread_rwlock.rs b/library/std/src/sys/unix/locks/pthread_rwlock.rs index adfe2a883..04662be9d 100644 --- a/library/std/src/sys/unix/locks/pthread_rwlock.rs +++ b/library/std/src/sys/unix/locks/pthread_rwlock.rs @@ -3,20 +3,26 @@ use crate::mem::forget; use crate::sync::atomic::{AtomicUsize, Ordering}; use crate::sys_common::lazy_box::{LazyBox, LazyInit}; -pub struct RwLock { +struct AllocatedRwLock { inner: UnsafeCell<libc::pthread_rwlock_t>, write_locked: UnsafeCell<bool>, // guarded by the `inner` RwLock num_readers: AtomicUsize, } -pub(crate) type MovableRwLock = LazyBox<RwLock>; +unsafe impl Send for AllocatedRwLock {} +unsafe impl Sync for AllocatedRwLock {} -unsafe impl Send for RwLock {} -unsafe impl Sync for RwLock {} +pub struct RwLock { + inner: LazyBox<AllocatedRwLock>, +} -impl LazyInit for RwLock { +impl LazyInit for AllocatedRwLock { fn init() -> Box<Self> { - Box::new(Self::new()) + Box::new(AllocatedRwLock { + inner: UnsafeCell::new(libc::PTHREAD_RWLOCK_INITIALIZER), + write_locked: UnsafeCell::new(false), + num_readers: AtomicUsize::new(0), + }) } fn destroy(mut rwlock: Box<Self>) { @@ -35,17 +41,39 @@ impl LazyInit for RwLock { } } +impl AllocatedRwLock { + #[inline] + unsafe fn raw_unlock(&self) { + let r = libc::pthread_rwlock_unlock(self.inner.get()); + debug_assert_eq!(r, 0); + } +} + +impl Drop for AllocatedRwLock { + fn drop(&mut self) { + let r = unsafe { libc::pthread_rwlock_destroy(self.inner.get()) }; + // On DragonFly pthread_rwlock_destroy() returns EINVAL if called on a + // rwlock that was just initialized with + // libc::PTHREAD_RWLOCK_INITIALIZER. Once it is used (locked/unlocked) + // or pthread_rwlock_init() is called, this behaviour no longer occurs. + if cfg!(target_os = "dragonfly") { + debug_assert!(r == 0 || r == libc::EINVAL); + } else { + debug_assert_eq!(r, 0); + } + } +} + impl RwLock { + #[inline] pub const fn new() -> RwLock { - RwLock { - inner: UnsafeCell::new(libc::PTHREAD_RWLOCK_INITIALIZER), - write_locked: UnsafeCell::new(false), - num_readers: AtomicUsize::new(0), - } + RwLock { inner: LazyBox::new() } } + #[inline] - pub unsafe fn read(&self) { - let r = libc::pthread_rwlock_rdlock(self.inner.get()); + pub fn read(&self) { + let lock = &*self.inner; + let r = unsafe { libc::pthread_rwlock_rdlock(lock.inner.get()) }; // According to POSIX, when a thread tries to acquire this read lock // while it already holds the write lock @@ -62,51 +90,61 @@ impl RwLock { // got the write lock more than once, or got a read and a write lock. if r == libc::EAGAIN { panic!("rwlock maximum reader count exceeded"); - } else if r == libc::EDEADLK || (r == 0 && *self.write_locked.get()) { + } else if r == libc::EDEADLK || (r == 0 && unsafe { *lock.write_locked.get() }) { // Above, we make sure to only access `write_locked` when `r == 0` to avoid // data races. if r == 0 { // `pthread_rwlock_rdlock` succeeded when it should not have. - self.raw_unlock(); + unsafe { + lock.raw_unlock(); + } } panic!("rwlock read lock would result in deadlock"); } else { // POSIX does not make guarantees about all the errors that may be returned. // See issue #94705 for more details. assert_eq!(r, 0, "unexpected error during rwlock read lock: {:?}", r); - self.num_readers.fetch_add(1, Ordering::Relaxed); + lock.num_readers.fetch_add(1, Ordering::Relaxed); } } + #[inline] - pub unsafe fn try_read(&self) -> bool { - let r = libc::pthread_rwlock_tryrdlock(self.inner.get()); + pub fn try_read(&self) -> bool { + let lock = &*self.inner; + let r = unsafe { libc::pthread_rwlock_tryrdlock(lock.inner.get()) }; if r == 0 { - if *self.write_locked.get() { + if unsafe { *lock.write_locked.get() } { // `pthread_rwlock_tryrdlock` succeeded when it should not have. - self.raw_unlock(); + unsafe { + lock.raw_unlock(); + } false } else { - self.num_readers.fetch_add(1, Ordering::Relaxed); + lock.num_readers.fetch_add(1, Ordering::Relaxed); true } } else { false } } + #[inline] - pub unsafe fn write(&self) { - let r = libc::pthread_rwlock_wrlock(self.inner.get()); + pub fn write(&self) { + let lock = &*self.inner; + let r = unsafe { libc::pthread_rwlock_wrlock(lock.inner.get()) }; // See comments above for why we check for EDEADLK and write_locked. For the same reason, // we also need to check that there are no readers (tracked in `num_readers`). if r == libc::EDEADLK - || (r == 0 && *self.write_locked.get()) - || self.num_readers.load(Ordering::Relaxed) != 0 + || (r == 0 && unsafe { *lock.write_locked.get() }) + || lock.num_readers.load(Ordering::Relaxed) != 0 { // Above, we make sure to only access `write_locked` when `r == 0` to avoid // data races. if r == 0 { // `pthread_rwlock_wrlock` succeeded when it should not have. - self.raw_unlock(); + unsafe { + lock.raw_unlock(); + } } panic!("rwlock write lock would result in deadlock"); } else { @@ -114,60 +152,44 @@ impl RwLock { // return EDEADLK or 0. We rely on that. debug_assert_eq!(r, 0); } - *self.write_locked.get() = true; + + unsafe { + *lock.write_locked.get() = true; + } } + #[inline] pub unsafe fn try_write(&self) -> bool { - let r = libc::pthread_rwlock_trywrlock(self.inner.get()); + let lock = &*self.inner; + let r = libc::pthread_rwlock_trywrlock(lock.inner.get()); if r == 0 { - if *self.write_locked.get() || self.num_readers.load(Ordering::Relaxed) != 0 { + if *lock.write_locked.get() || lock.num_readers.load(Ordering::Relaxed) != 0 { // `pthread_rwlock_trywrlock` succeeded when it should not have. - self.raw_unlock(); + lock.raw_unlock(); false } else { - *self.write_locked.get() = true; + *lock.write_locked.get() = true; true } } else { false } } - #[inline] - unsafe fn raw_unlock(&self) { - let r = libc::pthread_rwlock_unlock(self.inner.get()); - debug_assert_eq!(r, 0); - } + #[inline] pub unsafe fn read_unlock(&self) { - debug_assert!(!*self.write_locked.get()); - self.num_readers.fetch_sub(1, Ordering::Relaxed); - self.raw_unlock(); - } - #[inline] - pub unsafe fn write_unlock(&self) { - debug_assert_eq!(self.num_readers.load(Ordering::Relaxed), 0); - debug_assert!(*self.write_locked.get()); - *self.write_locked.get() = false; - self.raw_unlock(); + let lock = &*self.inner; + debug_assert!(!*lock.write_locked.get()); + lock.num_readers.fetch_sub(1, Ordering::Relaxed); + lock.raw_unlock(); } - #[inline] - unsafe fn destroy(&mut self) { - let r = libc::pthread_rwlock_destroy(self.inner.get()); - // On DragonFly pthread_rwlock_destroy() returns EINVAL if called on a - // rwlock that was just initialized with - // libc::PTHREAD_RWLOCK_INITIALIZER. Once it is used (locked/unlocked) - // or pthread_rwlock_init() is called, this behaviour no longer occurs. - if cfg!(target_os = "dragonfly") { - debug_assert!(r == 0 || r == libc::EINVAL); - } else { - debug_assert_eq!(r, 0); - } - } -} -impl Drop for RwLock { #[inline] - fn drop(&mut self) { - unsafe { self.destroy() }; + pub unsafe fn write_unlock(&self) { + let lock = &*self.inner; + debug_assert_eq!(lock.num_readers.load(Ordering::Relaxed), 0); + debug_assert!(*lock.write_locked.get()); + *lock.write_locked.get() = false; + lock.raw_unlock(); } } diff --git a/library/std/src/sys/unix/time.rs b/library/std/src/sys/unix/time.rs index cca9c6767..d5abd9b58 100644 --- a/library/std/src/sys/unix/time.rs +++ b/library/std/src/sys/unix/time.rs @@ -149,7 +149,11 @@ impl From<libc::timespec> for Timespec { } } -#[cfg(any(target_os = "macos", target_os = "ios", target_os = "watchos"))] +#[cfg(any( + all(target_os = "macos", any(not(target_arch = "aarch64"))), + target_os = "ios", + target_os = "watchos" +))] mod inner { use crate::sync::atomic::{AtomicU64, Ordering}; use crate::sys::cvt; @@ -265,7 +269,11 @@ mod inner { } } -#[cfg(not(any(target_os = "macos", target_os = "ios", target_os = "watchos")))] +#[cfg(not(any( + all(target_os = "macos", any(not(target_arch = "aarch64"))), + target_os = "ios", + target_os = "watchos" +)))] mod inner { use crate::fmt; use crate::mem::MaybeUninit; @@ -281,7 +289,11 @@ mod inner { impl Instant { pub fn now() -> Instant { - Instant { t: Timespec::now(libc::CLOCK_MONOTONIC) } + #[cfg(target_os = "macos")] + const clock_id: libc::clockid_t = libc::CLOCK_UPTIME_RAW; + #[cfg(not(target_os = "macos"))] + const clock_id: libc::clockid_t = libc::CLOCK_MONOTONIC; + Instant { t: Timespec::now(clock_id) } } pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> { @@ -312,13 +324,8 @@ mod inner { } } - #[cfg(not(any(target_os = "dragonfly", target_os = "espidf", target_os = "horizon")))] - pub type clock_t = libc::c_int; - #[cfg(any(target_os = "dragonfly", target_os = "espidf", target_os = "horizon"))] - pub type clock_t = libc::c_ulong; - impl Timespec { - pub fn now(clock: clock_t) -> Timespec { + pub fn now(clock: libc::clockid_t) -> Timespec { // Try to use 64-bit time in preparation for Y2038. #[cfg(all(target_os = "linux", target_env = "gnu", target_pointer_width = "32"))] { diff --git a/library/std/src/sys/unix/weak.rs b/library/std/src/sys/unix/weak.rs index e4ff21b25..f5a4ce929 100644 --- a/library/std/src/sys/unix/weak.rs +++ b/library/std/src/sys/unix/weak.rs @@ -29,7 +29,21 @@ use crate::ptr; use crate::sync::atomic::{self, AtomicPtr, Ordering}; // We can use true weak linkage on ELF targets. -#[cfg(not(any(target_os = "macos", target_os = "ios")))] +#[cfg(all(not(any(target_os = "macos", target_os = "ios")), not(bootstrap)))] +pub(crate) macro weak { + (fn $name:ident($($t:ty),*) -> $ret:ty) => ( + let ref $name: ExternWeak<unsafe extern "C" fn($($t),*) -> $ret> = { + extern "C" { + #[linkage = "extern_weak"] + static $name: Option<unsafe extern "C" fn($($t),*) -> $ret>; + } + #[allow(unused_unsafe)] + ExternWeak::new(unsafe { $name }) + }; + ) +} + +#[cfg(all(not(any(target_os = "macos", target_os = "ios")), bootstrap))] pub(crate) macro weak { (fn $name:ident($($t:ty),*) -> $ret:ty) => ( let ref $name: ExternWeak<unsafe extern "C" fn($($t),*) -> $ret> = { @@ -47,11 +61,31 @@ pub(crate) macro weak { #[cfg(any(target_os = "macos", target_os = "ios"))] pub(crate) use self::dlsym as weak; +#[cfg(not(bootstrap))] +pub(crate) struct ExternWeak<F: Copy> { + weak_ptr: Option<F>, +} + +#[cfg(not(bootstrap))] +impl<F: Copy> ExternWeak<F> { + #[inline] + pub(crate) fn new(weak_ptr: Option<F>) -> Self { + ExternWeak { weak_ptr } + } + + #[inline] + pub(crate) fn get(&self) -> Option<F> { + self.weak_ptr + } +} + +#[cfg(bootstrap)] pub(crate) struct ExternWeak<F> { weak_ptr: *const libc::c_void, _marker: PhantomData<F>, } +#[cfg(bootstrap)] impl<F> ExternWeak<F> { #[inline] pub(crate) fn new(weak_ptr: *const libc::c_void) -> Self { @@ -59,6 +93,7 @@ impl<F> ExternWeak<F> { } } +#[cfg(bootstrap)] impl<F> ExternWeak<F> { #[inline] pub(crate) fn get(&self) -> Option<F> { diff --git a/library/std/src/sys/unsupported/locks/condvar.rs b/library/std/src/sys/unsupported/locks/condvar.rs index 527a26a12..3f0943b50 100644 --- a/library/std/src/sys/unsupported/locks/condvar.rs +++ b/library/std/src/sys/unsupported/locks/condvar.rs @@ -3,8 +3,6 @@ use crate::time::Duration; pub struct Condvar {} -pub type MovableCondvar = Condvar; - impl Condvar { #[inline] #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] @@ -13,10 +11,10 @@ impl Condvar { } #[inline] - pub unsafe fn notify_one(&self) {} + pub fn notify_one(&self) {} #[inline] - pub unsafe fn notify_all(&self) {} + pub fn notify_all(&self) {} pub unsafe fn wait(&self, _mutex: &Mutex) { panic!("condvar wait not supported") diff --git a/library/std/src/sys/unsupported/locks/mod.rs b/library/std/src/sys/unsupported/locks/mod.rs index 602a2d623..0e0f9eccb 100644 --- a/library/std/src/sys/unsupported/locks/mod.rs +++ b/library/std/src/sys/unsupported/locks/mod.rs @@ -1,6 +1,6 @@ mod condvar; mod mutex; mod rwlock; -pub use condvar::{Condvar, MovableCondvar}; -pub use mutex::{MovableMutex, Mutex}; -pub use rwlock::MovableRwLock; +pub use condvar::Condvar; +pub use mutex::Mutex; +pub use rwlock::RwLock; diff --git a/library/std/src/sys/unsupported/locks/mutex.rs b/library/std/src/sys/unsupported/locks/mutex.rs index 87ea475c6..4a13c55fb 100644 --- a/library/std/src/sys/unsupported/locks/mutex.rs +++ b/library/std/src/sys/unsupported/locks/mutex.rs @@ -5,8 +5,6 @@ pub struct Mutex { locked: Cell<bool>, } -pub type MovableMutex = Mutex; - unsafe impl Send for Mutex {} unsafe impl Sync for Mutex {} // no threads on this platform @@ -18,7 +16,7 @@ impl Mutex { } #[inline] - pub unsafe fn lock(&self) { + pub fn lock(&self) { assert_eq!(self.locked.replace(true), false, "cannot recursively acquire mutex"); } @@ -28,7 +26,7 @@ impl Mutex { } #[inline] - pub unsafe fn try_lock(&self) -> bool { + pub fn try_lock(&self) -> bool { self.locked.replace(true) == false } } diff --git a/library/std/src/sys/unsupported/locks/rwlock.rs b/library/std/src/sys/unsupported/locks/rwlock.rs index 5292691b9..789ef9b29 100644 --- a/library/std/src/sys/unsupported/locks/rwlock.rs +++ b/library/std/src/sys/unsupported/locks/rwlock.rs @@ -5,8 +5,6 @@ pub struct RwLock { mode: Cell<isize>, } -pub type MovableRwLock = RwLock; - unsafe impl Send for RwLock {} unsafe impl Sync for RwLock {} // no threads on this platform @@ -18,7 +16,7 @@ impl RwLock { } #[inline] - pub unsafe fn read(&self) { + pub fn read(&self) { let m = self.mode.get(); if m >= 0 { self.mode.set(m + 1); @@ -28,7 +26,7 @@ impl RwLock { } #[inline] - pub unsafe fn try_read(&self) -> bool { + pub fn try_read(&self) -> bool { let m = self.mode.get(); if m >= 0 { self.mode.set(m + 1); @@ -39,14 +37,14 @@ impl RwLock { } #[inline] - pub unsafe fn write(&self) { + pub fn write(&self) { if self.mode.replace(-1) != 0 { rtabort!("rwlock locked for reading") } } #[inline] - pub unsafe fn try_write(&self) -> bool { + pub fn try_write(&self) -> bool { if self.mode.get() == 0 { self.mode.set(-1); true diff --git a/library/std/src/sys/wasi/net.rs b/library/std/src/sys/wasi/net.rs index 590d268c3..cf4ebba1a 100644 --- a/library/std/src/sys/wasi/net.rs +++ b/library/std/src/sys/wasi/net.rs @@ -119,8 +119,14 @@ impl TcpStream { unsupported() } - pub fn shutdown(&self, _: Shutdown) -> io::Result<()> { - unsupported() + pub fn shutdown(&self, how: Shutdown) -> io::Result<()> { + let wasi_how = match how { + Shutdown::Read => wasi::SDFLAGS_RD, + Shutdown::Write => wasi::SDFLAGS_WR, + Shutdown::Both => wasi::SDFLAGS_RD | wasi::SDFLAGS_WR, + }; + + unsafe { wasi::sock_shutdown(self.socket().as_raw_fd() as _, wasi_how).map_err(err2io) } } pub fn duplicate(&self) -> io::Result<TcpStream> { diff --git a/library/std/src/sys/wasm/mod.rs b/library/std/src/sys/wasm/mod.rs index 93838390b..d68c3e5f1 100644 --- a/library/std/src/sys/wasm/mod.rs +++ b/library/std/src/sys/wasm/mod.rs @@ -55,9 +55,9 @@ cfg_if::cfg_if! { mod futex_condvar; mod futex_mutex; mod futex_rwlock; - pub(crate) use futex_condvar::{Condvar, MovableCondvar}; - pub(crate) use futex_mutex::{Mutex, MovableMutex}; - pub(crate) use futex_rwlock::MovableRwLock; + pub(crate) use futex_condvar::Condvar; + pub(crate) use futex_mutex::Mutex; + pub(crate) use futex_rwlock::RwLock; } #[path = "atomics/futex.rs"] pub mod futex; diff --git a/library/std/src/sys/windows/args.rs b/library/std/src/sys/windows/args.rs index 01f262982..6741ae46d 100644 --- a/library/std/src/sys/windows/args.rs +++ b/library/std/src/sys/windows/args.rs @@ -9,17 +9,16 @@ mod tests; use crate::ffi::OsString; use crate::fmt; use crate::io; -use crate::marker::PhantomData; use crate::num::NonZeroU16; use crate::os::windows::prelude::*; use crate::path::PathBuf; -use crate::ptr::NonNull; use crate::sys::c; use crate::sys::process::ensure_no_nuls; use crate::sys::windows::os::current_exe; +use crate::sys_common::wstr::WStrUnits; use crate::vec; -use core::iter; +use crate::iter; /// This is the const equivalent to `NonZeroU16::new(n).unwrap()` /// @@ -199,55 +198,6 @@ impl ExactSizeIterator for Args { } } -/// A safe iterator over a LPWSTR -/// (aka a pointer to a series of UTF-16 code units terminated by a NULL). -struct WStrUnits<'a> { - // The pointer must never be null... - lpwstr: NonNull<u16>, - // ...and the memory it points to must be valid for this lifetime. - lifetime: PhantomData<&'a [u16]>, -} -impl WStrUnits<'_> { - /// Create the iterator. Returns `None` if `lpwstr` is null. - /// - /// SAFETY: `lpwstr` must point to a null-terminated wide string that lives - /// at least as long as the lifetime of this struct. - unsafe fn new(lpwstr: *const u16) -> Option<Self> { - Some(Self { lpwstr: NonNull::new(lpwstr as _)?, lifetime: PhantomData }) - } - fn peek(&self) -> Option<NonZeroU16> { - // SAFETY: It's always safe to read the current item because we don't - // ever move out of the array's bounds. - unsafe { NonZeroU16::new(*self.lpwstr.as_ptr()) } - } - /// Advance the iterator while `predicate` returns true. - /// Returns the number of items it advanced by. - fn advance_while<P: FnMut(NonZeroU16) -> bool>(&mut self, mut predicate: P) -> usize { - let mut counter = 0; - while let Some(w) = self.peek() { - if !predicate(w) { - break; - } - counter += 1; - self.next(); - } - counter - } -} -impl Iterator for WStrUnits<'_> { - // This can never return zero as that marks the end of the string. - type Item = NonZeroU16; - fn next(&mut self) -> Option<NonZeroU16> { - // SAFETY: If NULL is reached we immediately return. - // Therefore it's safe to advance the pointer after that. - unsafe { - let next = self.peek()?; - self.lpwstr = NonNull::new_unchecked(self.lpwstr.as_ptr().add(1)); - Some(next) - } - } -} - #[derive(Debug)] pub(crate) enum Arg { /// Add quotes (if needed) diff --git a/library/std/src/sys/windows/c.rs b/library/std/src/sys/windows/c.rs index be6fc2ebb..81461de4f 100644 --- a/library/std/src/sys/windows/c.rs +++ b/library/std/src/sys/windows/c.rs @@ -56,6 +56,7 @@ pub type LPPROCESS_INFORMATION = *mut PROCESS_INFORMATION; pub type LPSECURITY_ATTRIBUTES = *mut SECURITY_ATTRIBUTES; pub type LPSTARTUPINFO = *mut STARTUPINFO; pub type LPVOID = *mut c_void; +pub type LPCVOID = *const c_void; pub type LPWCH = *mut WCHAR; pub type LPWIN32_FIND_DATAW = *mut WIN32_FIND_DATAW; pub type LPWSADATA = *mut WSADATA; @@ -362,7 +363,7 @@ impl IO_STATUS_BLOCK { pub type LPOVERLAPPED_COMPLETION_ROUTINE = unsafe extern "system" fn( dwErrorCode: DWORD, - dwNumberOfBytesTransfered: DWORD, + dwNumberOfBytesTransferred: DWORD, lpOverlapped: *mut OVERLAPPED, ); @@ -773,6 +774,16 @@ pub struct timeval { pub tv_usec: c_long, } +#[repr(C)] +#[derive(Copy, Clone)] +pub struct CONSOLE_READCONSOLE_CONTROL { + pub nLength: ULONG, + pub nInitialChars: ULONG, + pub dwCtrlWakeupMask: ULONG, + pub dwControlKeyState: ULONG, +} +pub type PCONSOLE_READCONSOLE_CONTROL = *mut CONSOLE_READCONSOLE_CONTROL; + // Desktop specific functions & types cfg_if::cfg_if! { if #[cfg(not(target_vendor = "uwp"))] { @@ -802,17 +813,6 @@ if #[cfg(not(target_vendor = "uwp"))] { extern "system" fn(ExceptionInfo: *mut EXCEPTION_POINTERS) -> LONG; #[repr(C)] - #[derive(Copy, Clone)] - pub struct CONSOLE_READCONSOLE_CONTROL { - pub nLength: ULONG, - pub nInitialChars: ULONG, - pub dwCtrlWakeupMask: ULONG, - pub dwControlKeyState: ULONG, - } - - pub type PCONSOLE_READCONSOLE_CONTROL = *mut CONSOLE_READCONSOLE_CONTROL; - - #[repr(C)] pub struct BY_HANDLE_FILE_INFORMATION { pub dwFileAttributes: DWORD, pub ftCreationTime: FILETIME, @@ -827,7 +827,6 @@ if #[cfg(not(target_vendor = "uwp"))] { } pub type LPBY_HANDLE_FILE_INFORMATION = *mut BY_HANDLE_FILE_INFORMATION; - pub type LPCVOID = *const c_void; pub const HANDLE_FLAG_INHERIT: DWORD = 0x00000001; @@ -855,24 +854,6 @@ if #[cfg(not(target_vendor = "uwp"))] { #[link(name = "kernel32")] extern "system" { - // Functions forbidden when targeting UWP - pub fn ReadConsoleW( - hConsoleInput: HANDLE, - lpBuffer: LPVOID, - nNumberOfCharsToRead: DWORD, - lpNumberOfCharsRead: LPDWORD, - pInputControl: PCONSOLE_READCONSOLE_CONTROL, - ) -> BOOL; - - pub fn WriteConsoleW( - hConsoleOutput: HANDLE, - lpBuffer: LPCVOID, - nNumberOfCharsToWrite: DWORD, - lpNumberOfCharsWritten: LPDWORD, - lpReserved: LPVOID, - ) -> BOOL; - - pub fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL; // Allowed but unused by UWP pub fn GetFileInformationByHandle( hFile: HANDLE, @@ -914,6 +895,22 @@ if #[cfg(target_vendor = "uwp")] { extern "system" { pub fn GetCurrentProcessId() -> DWORD; + pub fn ReadConsoleW( + hConsoleInput: HANDLE, + lpBuffer: LPVOID, + nNumberOfCharsToRead: DWORD, + lpNumberOfCharsRead: LPDWORD, + pInputControl: PCONSOLE_READCONSOLE_CONTROL, + ) -> BOOL; + pub fn WriteConsoleW( + hConsoleOutput: HANDLE, + lpBuffer: LPCVOID, + nNumberOfCharsToWrite: DWORD, + lpNumberOfCharsWritten: LPDWORD, + lpReserved: LPVOID, + ) -> BOOL; + pub fn GetConsoleMode(hConsoleHandle: HANDLE, lpMode: LPDWORD) -> BOOL; + pub fn GetSystemDirectoryW(lpBuffer: LPWSTR, uSize: UINT) -> UINT; pub fn RemoveDirectoryW(lpPathName: LPCWSTR) -> BOOL; pub fn SetFileAttributesW(lpFileName: LPCWSTR, dwFileAttributes: DWORD) -> BOOL; diff --git a/library/std/src/sys/windows/locks/condvar.rs b/library/std/src/sys/windows/locks/condvar.rs index be9a2abbe..66fafa2c0 100644 --- a/library/std/src/sys/windows/locks/condvar.rs +++ b/library/std/src/sys/windows/locks/condvar.rs @@ -8,8 +8,6 @@ pub struct Condvar { inner: UnsafeCell<c::CONDITION_VARIABLE>, } -pub type MovableCondvar = Condvar; - unsafe impl Send for Condvar {} unsafe impl Sync for Condvar {} @@ -41,12 +39,12 @@ impl Condvar { } #[inline] - pub unsafe fn notify_one(&self) { - c::WakeConditionVariable(self.inner.get()) + pub fn notify_one(&self) { + unsafe { c::WakeConditionVariable(self.inner.get()) } } #[inline] - pub unsafe fn notify_all(&self) { - c::WakeAllConditionVariable(self.inner.get()) + pub fn notify_all(&self) { + unsafe { c::WakeAllConditionVariable(self.inner.get()) } } } diff --git a/library/std/src/sys/windows/locks/mod.rs b/library/std/src/sys/windows/locks/mod.rs index 602a2d623..0e0f9eccb 100644 --- a/library/std/src/sys/windows/locks/mod.rs +++ b/library/std/src/sys/windows/locks/mod.rs @@ -1,6 +1,6 @@ mod condvar; mod mutex; mod rwlock; -pub use condvar::{Condvar, MovableCondvar}; -pub use mutex::{MovableMutex, Mutex}; -pub use rwlock::MovableRwLock; +pub use condvar::Condvar; +pub use mutex::Mutex; +pub use rwlock::RwLock; diff --git a/library/std/src/sys/windows/locks/mutex.rs b/library/std/src/sys/windows/locks/mutex.rs index 91207f5f4..ef2f84082 100644 --- a/library/std/src/sys/windows/locks/mutex.rs +++ b/library/std/src/sys/windows/locks/mutex.rs @@ -21,9 +21,6 @@ pub struct Mutex { srwlock: UnsafeCell<c::SRWLOCK>, } -// Windows SRW Locks are movable (while not borrowed). -pub type MovableMutex = Mutex; - unsafe impl Send for Mutex {} unsafe impl Sync for Mutex {} @@ -39,13 +36,15 @@ impl Mutex { } #[inline] - pub unsafe fn lock(&self) { - c::AcquireSRWLockExclusive(raw(self)); + pub fn lock(&self) { + unsafe { + c::AcquireSRWLockExclusive(raw(self)); + } } #[inline] - pub unsafe fn try_lock(&self) -> bool { - c::TryAcquireSRWLockExclusive(raw(self)) != 0 + pub fn try_lock(&self) -> bool { + unsafe { c::TryAcquireSRWLockExclusive(raw(self)) != 0 } } #[inline] diff --git a/library/std/src/sys/windows/locks/rwlock.rs b/library/std/src/sys/windows/locks/rwlock.rs index fa5ffe574..e69415baa 100644 --- a/library/std/src/sys/windows/locks/rwlock.rs +++ b/library/std/src/sys/windows/locks/rwlock.rs @@ -5,8 +5,6 @@ pub struct RwLock { inner: UnsafeCell<c::SRWLOCK>, } -pub type MovableRwLock = RwLock; - unsafe impl Send for RwLock {} unsafe impl Sync for RwLock {} @@ -16,20 +14,20 @@ impl RwLock { RwLock { inner: UnsafeCell::new(c::SRWLOCK_INIT) } } #[inline] - pub unsafe fn read(&self) { - c::AcquireSRWLockShared(self.inner.get()) + pub fn read(&self) { + unsafe { c::AcquireSRWLockShared(self.inner.get()) } } #[inline] - pub unsafe fn try_read(&self) -> bool { - c::TryAcquireSRWLockShared(self.inner.get()) != 0 + pub fn try_read(&self) -> bool { + unsafe { c::TryAcquireSRWLockShared(self.inner.get()) != 0 } } #[inline] - pub unsafe fn write(&self) { - c::AcquireSRWLockExclusive(self.inner.get()) + pub fn write(&self) { + unsafe { c::AcquireSRWLockExclusive(self.inner.get()) } } #[inline] - pub unsafe fn try_write(&self) -> bool { - c::TryAcquireSRWLockExclusive(self.inner.get()) != 0 + pub fn try_write(&self) -> bool { + unsafe { c::TryAcquireSRWLockExclusive(self.inner.get()) != 0 } } #[inline] pub unsafe fn read_unlock(&self) { diff --git a/library/std/src/sys/windows/mod.rs b/library/std/src/sys/windows/mod.rs index eab9b9612..e67411e16 100644 --- a/library/std/src/sys/windows/mod.rs +++ b/library/std/src/sys/windows/mod.rs @@ -29,6 +29,7 @@ pub mod path; pub mod pipe; pub mod process; pub mod rand; +pub mod stdio; pub mod thread; pub mod thread_local_dtor; pub mod thread_local_key; @@ -36,12 +37,9 @@ pub mod thread_parker; pub mod time; cfg_if::cfg_if! { if #[cfg(not(target_vendor = "uwp"))] { - pub mod stdio; pub mod stack_overflow; } else { - pub mod stdio_uwp; pub mod stack_overflow_uwp; - pub use self::stdio_uwp as stdio; pub use self::stack_overflow_uwp as stack_overflow; } } diff --git a/library/std/src/sys/windows/pipe.rs b/library/std/src/sys/windows/pipe.rs index 013c776c4..9f26acc45 100644 --- a/library/std/src/sys/windows/pipe.rs +++ b/library/std/src/sys/windows/pipe.rs @@ -324,17 +324,18 @@ impl AnonPipe { let mut async_result: Option<AsyncResult> = None; struct AsyncResult { error: u32, - transfered: u32, + transferred: u32, } // STEP 3: The callback. unsafe extern "system" fn callback( dwErrorCode: u32, - dwNumberOfBytesTransfered: u32, + dwNumberOfBytesTransferred: u32, lpOverlapped: *mut c::OVERLAPPED, ) { // Set `async_result` using a pointer smuggled through `hEvent`. - let result = AsyncResult { error: dwErrorCode, transfered: dwNumberOfBytesTransfered }; + let result = + AsyncResult { error: dwErrorCode, transferred: dwNumberOfBytesTransferred }; *(*lpOverlapped).hEvent.cast::<Option<AsyncResult>>() = Some(result); } @@ -365,7 +366,7 @@ impl AnonPipe { // STEP 4: Return the result. // `async_result` is always `Some` at this point match result.error { - c::ERROR_SUCCESS => Ok(result.transfered as usize), + c::ERROR_SUCCESS => Ok(result.transferred as usize), error => Err(io::Error::from_raw_os_error(error as _)), } } diff --git a/library/std/src/sys/windows/process.rs b/library/std/src/sys/windows/process.rs index 9cbb4ef19..31e9b34fb 100644 --- a/library/std/src/sys/windows/process.rs +++ b/library/std/src/sys/windows/process.rs @@ -252,10 +252,6 @@ impl Command { ) -> io::Result<(Process, StdioPipes)> { let maybe_env = self.env.capture_if_changed(); - let mut si = zeroed_startupinfo(); - si.cb = mem::size_of::<c::STARTUPINFO>() as c::DWORD; - si.dwFlags = c::STARTF_USESTDHANDLES; - let child_paths = if let Some(env) = maybe_env.as_ref() { env.get(&EnvKey::new("PATH")).map(|s| s.as_os_str()) } else { @@ -314,9 +310,21 @@ impl Command { let stdin = stdin.to_handle(c::STD_INPUT_HANDLE, &mut pipes.stdin)?; let stdout = stdout.to_handle(c::STD_OUTPUT_HANDLE, &mut pipes.stdout)?; let stderr = stderr.to_handle(c::STD_ERROR_HANDLE, &mut pipes.stderr)?; - si.hStdInput = stdin.as_raw_handle(); - si.hStdOutput = stdout.as_raw_handle(); - si.hStdError = stderr.as_raw_handle(); + + let mut si = zeroed_startupinfo(); + si.cb = mem::size_of::<c::STARTUPINFO>() as c::DWORD; + + // If at least one of stdin, stdout or stderr are set (i.e. are non null) + // then set the `hStd` fields in `STARTUPINFO`. + // Otherwise skip this and allow the OS to apply its default behaviour. + // This provides more consistent behaviour between Win7 and Win8+. + let is_set = |stdio: &Handle| !stdio.as_raw_handle().is_null(); + if is_set(&stderr) || is_set(&stdout) || is_set(&stdin) { + si.dwFlags |= c::STARTF_USESTDHANDLES; + si.hStdInput = stdin.as_raw_handle(); + si.hStdOutput = stdout.as_raw_handle(); + si.hStdError = stderr.as_raw_handle(); + } unsafe { cvt(c::CreateProcessW( @@ -513,9 +521,6 @@ fn program_exists(path: &Path) -> Option<Vec<u16>> { impl Stdio { fn to_handle(&self, stdio_id: c::DWORD, pipe: &mut Option<AnonPipe>) -> io::Result<Handle> { match *self { - // If no stdio handle is available, then inherit means that it - // should still be unavailable so propagate the - // INVALID_HANDLE_VALUE. Stdio::Inherit => match stdio::get_handle(stdio_id) { Ok(io) => unsafe { let io = Handle::from_raw_handle(io); @@ -523,7 +528,8 @@ impl Stdio { io.into_raw_handle(); ret }, - Err(..) => unsafe { Ok(Handle::from_raw_handle(c::INVALID_HANDLE_VALUE)) }, + // If no stdio handle is available, then propagate the null value. + Err(..) => unsafe { Ok(Handle::from_raw_handle(ptr::null_mut())) }, }, Stdio::MakePipe => { @@ -730,9 +736,9 @@ fn zeroed_startupinfo() -> c::STARTUPINFO { wShowWindow: 0, cbReserved2: 0, lpReserved2: ptr::null_mut(), - hStdInput: c::INVALID_HANDLE_VALUE, - hStdOutput: c::INVALID_HANDLE_VALUE, - hStdError: c::INVALID_HANDLE_VALUE, + hStdInput: ptr::null_mut(), + hStdOutput: ptr::null_mut(), + hStdError: ptr::null_mut(), } } diff --git a/library/std/src/sys/windows/stdio_uwp.rs b/library/std/src/sys/windows/stdio_uwp.rs deleted file mode 100644 index 32550f796..000000000 --- a/library/std/src/sys/windows/stdio_uwp.rs +++ /dev/null @@ -1,87 +0,0 @@ -#![unstable(issue = "none", feature = "windows_stdio")] - -use crate::io; -use crate::mem::ManuallyDrop; -use crate::os::windows::io::FromRawHandle; -use crate::sys::c; -use crate::sys::handle::Handle; - -pub struct Stdin {} -pub struct Stdout; -pub struct Stderr; - -const MAX_BUFFER_SIZE: usize = 8192; -pub const STDIN_BUF_SIZE: usize = MAX_BUFFER_SIZE / 2 * 3; - -pub fn get_handle(handle_id: c::DWORD) -> io::Result<c::HANDLE> { - let handle = unsafe { c::GetStdHandle(handle_id) }; - if handle == c::INVALID_HANDLE_VALUE { - Err(io::Error::last_os_error()) - } else if handle.is_null() { - Err(io::Error::from_raw_os_error(c::ERROR_INVALID_HANDLE as i32)) - } else { - Ok(handle) - } -} - -fn write(handle_id: c::DWORD, data: &[u8]) -> io::Result<usize> { - let handle = get_handle(handle_id)?; - // SAFETY: The handle returned from `get_handle` must be valid and non-null. - let handle = unsafe { Handle::from_raw_handle(handle) }; - ManuallyDrop::new(handle).write(data) -} - -impl Stdin { - pub const fn new() -> Stdin { - Stdin {} - } -} - -impl io::Read for Stdin { - fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { - let handle = get_handle(c::STD_INPUT_HANDLE)?; - // SAFETY: The handle returned from `get_handle` must be valid and non-null. - let handle = unsafe { Handle::from_raw_handle(handle) }; - ManuallyDrop::new(handle).read(buf) - } -} - -impl Stdout { - pub const fn new() -> Stdout { - Stdout - } -} - -impl io::Write for Stdout { - fn write(&mut self, buf: &[u8]) -> io::Result<usize> { - write(c::STD_OUTPUT_HANDLE, buf) - } - - fn flush(&mut self) -> io::Result<()> { - Ok(()) - } -} - -impl Stderr { - pub const fn new() -> Stderr { - Stderr - } -} - -impl io::Write for Stderr { - fn write(&mut self, buf: &[u8]) -> io::Result<usize> { - write(c::STD_ERROR_HANDLE, buf) - } - - fn flush(&mut self) -> io::Result<()> { - Ok(()) - } -} - -pub fn is_ebadf(err: &io::Error) -> bool { - err.raw_os_error() == Some(c::ERROR_INVALID_HANDLE as i32) -} - -pub fn panic_output() -> Option<impl io::Write> { - Some(Stderr::new()) -} diff --git a/library/std/src/sys_common/condvar.rs b/library/std/src/sys_common/condvar.rs deleted file mode 100644 index 8bc5b2411..000000000 --- a/library/std/src/sys_common/condvar.rs +++ /dev/null @@ -1,57 +0,0 @@ -use crate::sys::locks as imp; -use crate::sys_common::mutex::MovableMutex; -use crate::time::Duration; - -mod check; - -type CondvarCheck = <imp::MovableMutex as check::CondvarCheck>::Check; - -/// An OS-based condition variable. -pub struct Condvar { - inner: imp::MovableCondvar, - check: CondvarCheck, -} - -impl Condvar { - /// Creates a new condition variable for use. - #[inline] - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self { inner: imp::MovableCondvar::new(), check: CondvarCheck::new() } - } - - /// Signals one waiter on this condition variable to wake up. - #[inline] - pub fn notify_one(&self) { - unsafe { self.inner.notify_one() }; - } - - /// Awakens all current waiters on this condition variable. - #[inline] - pub fn notify_all(&self) { - unsafe { self.inner.notify_all() }; - } - - /// Waits for a signal on the specified mutex. - /// - /// Behavior is undefined if the mutex is not locked by the current thread. - /// - /// May panic if used with more than one mutex. - #[inline] - pub unsafe fn wait(&self, mutex: &MovableMutex) { - self.check.verify(mutex); - self.inner.wait(mutex.raw()) - } - - /// Waits for a signal on the specified mutex with a timeout duration - /// specified by `dur` (a relative time into the future). - /// - /// Behavior is undefined if the mutex is not locked by the current thread. - /// - /// May panic if used with more than one mutex. - #[inline] - pub unsafe fn wait_timeout(&self, mutex: &MovableMutex, dur: Duration) -> bool { - self.check.verify(mutex); - self.inner.wait_timeout(mutex.raw(), dur) - } -} diff --git a/library/std/src/sys_common/condvar/check.rs b/library/std/src/sys_common/condvar/check.rs deleted file mode 100644 index 4ac9e62bf..000000000 --- a/library/std/src/sys_common/condvar/check.rs +++ /dev/null @@ -1,58 +0,0 @@ -use crate::ptr; -use crate::sync::atomic::{AtomicPtr, Ordering}; -use crate::sys::locks as imp; -use crate::sys_common::lazy_box::{LazyBox, LazyInit}; -use crate::sys_common::mutex::MovableMutex; - -pub trait CondvarCheck { - type Check; -} - -/// For boxed mutexes, a `Condvar` will check it's only ever used with the same -/// mutex, based on its (stable) address. -impl<T: LazyInit> CondvarCheck for LazyBox<T> { - type Check = SameMutexCheck; -} - -pub struct SameMutexCheck { - addr: AtomicPtr<()>, -} - -#[allow(dead_code)] -impl SameMutexCheck { - pub const fn new() -> Self { - Self { addr: AtomicPtr::new(ptr::null_mut()) } - } - pub fn verify(&self, mutex: &MovableMutex) { - let addr = mutex.raw() as *const imp::Mutex as *const () as *mut _; - // Relaxed is okay here because we never read through `self.addr`, and only use it to - // compare addresses. - match self.addr.compare_exchange( - ptr::null_mut(), - addr, - Ordering::Relaxed, - Ordering::Relaxed, - ) { - Ok(_) => {} // Stored the address - Err(n) if n == addr => {} // Lost a race to store the same address - _ => panic!("attempted to use a condition variable with two mutexes"), - } - } -} - -/// Unboxed mutexes may move, so `Condvar` can not require its address to stay -/// constant. -impl CondvarCheck for imp::Mutex { - type Check = NoCheck; -} - -pub struct NoCheck; - -#[allow(dead_code)] -impl NoCheck { - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self - } - pub fn verify(&self, _: &MovableMutex) {} -} diff --git a/library/std/src/sys_common/mod.rs b/library/std/src/sys_common/mod.rs index 8c19f9332..b1987aa0f 100644 --- a/library/std/src/sys_common/mod.rs +++ b/library/std/src/sys_common/mod.rs @@ -21,20 +21,18 @@ mod tests; pub mod backtrace; -pub mod condvar; pub mod fs; pub mod io; pub mod lazy_box; pub mod memchr; -pub mod mutex; pub mod once; pub mod process; pub mod remutex; -pub mod rwlock; pub mod thread; pub mod thread_info; pub mod thread_local_dtor; pub mod thread_parker; +pub mod wstr; pub mod wtf8; cfg_if::cfg_if! { diff --git a/library/std/src/sys_common/mutex.rs b/library/std/src/sys_common/mutex.rs deleted file mode 100644 index 98046f20f..000000000 --- a/library/std/src/sys_common/mutex.rs +++ /dev/null @@ -1,50 +0,0 @@ -use crate::sys::locks as imp; - -/// An OS-based mutual exclusion lock. -/// -/// This mutex cleans up its resources in its `Drop` implementation, may safely -/// be moved (when not borrowed), and does not cause UB when used reentrantly. -/// -/// This mutex does not implement poisoning. -/// -/// This is either a wrapper around `LazyBox<imp::Mutex>` or `imp::Mutex`, -/// depending on the platform. It is boxed on platforms where `imp::Mutex` may -/// not be moved. -pub struct MovableMutex(imp::MovableMutex); - -unsafe impl Sync for MovableMutex {} - -impl MovableMutex { - /// Creates a new mutex. - #[inline] - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self(imp::MovableMutex::new()) - } - - pub(super) fn raw(&self) -> &imp::Mutex { - &self.0 - } - - /// Locks the mutex blocking the current thread until it is available. - #[inline] - pub fn raw_lock(&self) { - unsafe { self.0.lock() } - } - - /// Attempts to lock the mutex without blocking, returning whether it was - /// successfully acquired or not. - #[inline] - pub fn try_lock(&self) -> bool { - unsafe { self.0.try_lock() } - } - - /// Unlocks the mutex. - /// - /// Behavior is undefined if the current thread does not actually hold the - /// mutex. - #[inline] - pub unsafe fn raw_unlock(&self) { - self.0.unlock() - } -} diff --git a/library/std/src/sys_common/once/generic.rs b/library/std/src/sys_common/once/generic.rs index acf5f2471..d953a6745 100644 --- a/library/std/src/sys_common/once/generic.rs +++ b/library/std/src/sys_common/once/generic.rs @@ -107,6 +107,7 @@ struct WaiterQueue<'a> { impl Once { #[inline] + #[rustc_const_stable(feature = "const_once_new", since = "1.32.0")] pub const fn new() -> Once { Once { state_and_queue: AtomicPtr::new(ptr::invalid_mut(INCOMPLETE)) } } diff --git a/library/std/src/sys_common/remutex.rs b/library/std/src/sys_common/remutex.rs index b448ae3a9..4c054da64 100644 --- a/library/std/src/sys_common/remutex.rs +++ b/library/std/src/sys_common/remutex.rs @@ -1,11 +1,11 @@ #[cfg(all(test, not(target_os = "emscripten")))] mod tests; -use super::mutex as sys; use crate::cell::UnsafeCell; use crate::ops::Deref; use crate::panic::{RefUnwindSafe, UnwindSafe}; use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed}; +use crate::sys::locks as sys; /// A re-entrant mutual exclusion /// @@ -39,7 +39,7 @@ use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed}; /// synchronization is left to the mutex, making relaxed memory ordering for /// the `owner` field fine in all cases. pub struct ReentrantMutex<T> { - mutex: sys::MovableMutex, + mutex: sys::Mutex, owner: AtomicUsize, lock_count: UnsafeCell<u32>, data: T, @@ -74,7 +74,7 @@ impl<T> ReentrantMutex<T> { /// Creates a new reentrant mutex in an unlocked state. pub const fn new(t: T) -> ReentrantMutex<T> { ReentrantMutex { - mutex: sys::MovableMutex::new(), + mutex: sys::Mutex::new(), owner: AtomicUsize::new(0), lock_count: UnsafeCell::new(0), data: t, @@ -100,7 +100,7 @@ impl<T> ReentrantMutex<T> { if self.owner.load(Relaxed) == this_thread { self.increment_lock_count(); } else { - self.mutex.raw_lock(); + self.mutex.lock(); self.owner.store(this_thread, Relaxed); debug_assert_eq!(*self.lock_count.get(), 0); *self.lock_count.get() = 1; @@ -162,7 +162,7 @@ impl<T> Drop for ReentrantMutexGuard<'_, T> { *self.lock.lock_count.get() -= 1; if *self.lock.lock_count.get() == 0 { self.lock.owner.store(0, Relaxed); - self.lock.mutex.raw_unlock(); + self.lock.mutex.unlock(); } } } diff --git a/library/std/src/sys_common/rwlock.rs b/library/std/src/sys_common/rwlock.rs deleted file mode 100644 index 042981dac..000000000 --- a/library/std/src/sys_common/rwlock.rs +++ /dev/null @@ -1,71 +0,0 @@ -use crate::sys::locks as imp; - -/// An OS-based reader-writer lock. -/// -/// This rwlock cleans up its resources in its `Drop` implementation and may -/// safely be moved (when not borrowed). -/// -/// This rwlock does not implement poisoning. -/// -/// This is either a wrapper around `LazyBox<imp::RwLock>` or `imp::RwLock`, -/// depending on the platform. It is boxed on platforms where `imp::RwLock` may -/// not be moved. -pub struct MovableRwLock(imp::MovableRwLock); - -impl MovableRwLock { - /// Creates a new reader-writer lock for use. - #[inline] - #[rustc_const_stable(feature = "const_locks", since = "1.63.0")] - pub const fn new() -> Self { - Self(imp::MovableRwLock::new()) - } - - /// Acquires shared access to the underlying lock, blocking the current - /// thread to do so. - #[inline] - pub fn read(&self) { - unsafe { self.0.read() } - } - - /// Attempts to acquire shared access to this lock, returning whether it - /// succeeded or not. - /// - /// This function does not block the current thread. - #[inline] - pub fn try_read(&self) -> bool { - unsafe { self.0.try_read() } - } - - /// Acquires write access to the underlying lock, blocking the current thread - /// to do so. - #[inline] - pub fn write(&self) { - unsafe { self.0.write() } - } - - /// Attempts to acquire exclusive access to this lock, returning whether it - /// succeeded or not. - /// - /// This function does not block the current thread. - #[inline] - pub fn try_write(&self) -> bool { - unsafe { self.0.try_write() } - } - - /// Unlocks previously acquired shared access to this lock. - /// - /// Behavior is undefined if the current thread does not have shared access. - #[inline] - pub unsafe fn read_unlock(&self) { - self.0.read_unlock() - } - - /// Unlocks previously acquired exclusive access to this lock. - /// - /// Behavior is undefined if the current thread does not currently have - /// exclusive access. - #[inline] - pub unsafe fn write_unlock(&self) { - self.0.write_unlock() - } -} diff --git a/library/std/src/sys_common/wstr.rs b/library/std/src/sys_common/wstr.rs new file mode 100644 index 000000000..b230fd1a8 --- /dev/null +++ b/library/std/src/sys_common/wstr.rs @@ -0,0 +1,59 @@ +//! This module contains constructs to work with 16-bit characters (UCS-2 or UTF-16) +#![allow(dead_code)] + +use crate::marker::PhantomData; +use crate::num::NonZeroU16; +use crate::ptr::NonNull; + +/// A safe iterator over a LPWSTR +/// (aka a pointer to a series of UTF-16 code units terminated by a NULL). +pub struct WStrUnits<'a> { + // The pointer must never be null... + lpwstr: NonNull<u16>, + // ...and the memory it points to must be valid for this lifetime. + lifetime: PhantomData<&'a [u16]>, +} + +impl WStrUnits<'_> { + /// Create the iterator. Returns `None` if `lpwstr` is null. + /// + /// SAFETY: `lpwstr` must point to a null-terminated wide string that lives + /// at least as long as the lifetime of this struct. + pub unsafe fn new(lpwstr: *const u16) -> Option<Self> { + Some(Self { lpwstr: NonNull::new(lpwstr as _)?, lifetime: PhantomData }) + } + + pub fn peek(&self) -> Option<NonZeroU16> { + // SAFETY: It's always safe to read the current item because we don't + // ever move out of the array's bounds. + unsafe { NonZeroU16::new(*self.lpwstr.as_ptr()) } + } + + /// Advance the iterator while `predicate` returns true. + /// Returns the number of items it advanced by. + pub fn advance_while<P: FnMut(NonZeroU16) -> bool>(&mut self, mut predicate: P) -> usize { + let mut counter = 0; + while let Some(w) = self.peek() { + if !predicate(w) { + break; + } + counter += 1; + self.next(); + } + counter + } +} + +impl Iterator for WStrUnits<'_> { + // This can never return zero as that marks the end of the string. + type Item = NonZeroU16; + fn next(&mut self) -> Option<NonZeroU16> { + // SAFETY: If NULL is reached we immediately return. + // Therefore it's safe to advance the pointer after that. + unsafe { + let next = self.peek()?; + self.lpwstr = NonNull::new_unchecked(self.lpwstr.as_ptr().add(1)); + Some(next) + } + } +} |