+++ /dev/null
-pub use ::alloc::sync::Arc;
-use core::ops::{Deref, DerefMut};
-use core::time::Duration;
-
-use std::cell::RefCell;
-
-use std::sync::atomic::{AtomicUsize, Ordering};
-use std::sync::Mutex as StdMutex;
-use std::sync::MutexGuard as StdMutexGuard;
-use std::sync::RwLock as StdRwLock;
-use std::sync::RwLockReadGuard as StdRwLockReadGuard;
-use std::sync::RwLockWriteGuard as StdRwLockWriteGuard;
-use std::sync::Condvar as StdCondvar;
-
-use crate::prelude::HashMap;
-
-#[cfg(feature = "backtrace")]
-use {crate::prelude::hash_map, backtrace::Backtrace, std::sync::Once};
-
-#[cfg(not(feature = "backtrace"))]
-struct Backtrace{}
-#[cfg(not(feature = "backtrace"))]
-impl Backtrace { fn new() -> Backtrace { Backtrace {} } }
-
-pub type LockResult<Guard> = Result<Guard, ()>;
-
-pub struct Condvar {
- inner: StdCondvar,
-}
-
-impl Condvar {
- pub fn new() -> Condvar {
- Condvar { inner: StdCondvar::new() }
- }
-
- pub fn wait<'a, T>(&'a self, guard: MutexGuard<'a, T>) -> LockResult<MutexGuard<'a, T>> {
- let mutex: &'a Mutex<T> = guard.mutex;
- self.inner.wait(guard.into_inner()).map(|lock| MutexGuard { mutex, lock }).map_err(|_| ())
- }
-
- #[allow(unused)]
- pub fn wait_timeout<'a, T>(&'a self, guard: MutexGuard<'a, T>, dur: Duration) -> LockResult<(MutexGuard<'a, T>, ())> {
- let mutex = guard.mutex;
- self.inner.wait_timeout(guard.into_inner(), dur).map(|(lock, _)| (MutexGuard { mutex, lock }, ())).map_err(|_| ())
- }
-
- pub fn notify_all(&self) { self.inner.notify_all(); }
-}
-
-thread_local! {
- /// We track the set of locks currently held by a reference to their `LockMetadata`
- static LOCKS_HELD: RefCell<HashMap<u64, Arc<LockMetadata>>> = RefCell::new(HashMap::new());
-}
-static LOCK_IDX: AtomicUsize = AtomicUsize::new(0);
-
-#[cfg(feature = "backtrace")]
-static mut LOCKS: Option<StdMutex<HashMap<String, Arc<LockMetadata>>>> = None;
-#[cfg(feature = "backtrace")]
-static LOCKS_INIT: Once = Once::new();
-
-/// Metadata about a single lock, by id, the set of things locked-before it, and the backtrace of
-/// when the Mutex itself was constructed.
-struct LockMetadata {
- lock_idx: u64,
- locked_before: StdMutex<HashMap<u64, LockDep>>,
- _lock_construction_bt: Backtrace,
-}
-
-struct LockDep {
- lock: Arc<LockMetadata>,
- /// lockdep_trace is unused unless we're building with `backtrace`, so we mark it _
- _lockdep_trace: Backtrace,
-}
-
-#[cfg(feature = "backtrace")]
-fn get_construction_location(backtrace: &Backtrace) -> String {
- // Find the first frame that is after `debug_sync` (or that is in our tests) and use
- // that as the mutex construction site. Note that the first few frames may be in
- // the `backtrace` crate, so we have to ignore those.
- let sync_mutex_constr_regex = regex::Regex::new(r"lightning.*debug_sync.*new").unwrap();
- let mut found_debug_sync = false;
- for frame in backtrace.frames() {
- for symbol in frame.symbols() {
- let symbol_name = symbol.name().unwrap().as_str().unwrap();
- if !sync_mutex_constr_regex.is_match(symbol_name) {
- if found_debug_sync {
- if let Some(col) = symbol.colno() {
- return format!("{}:{}:{}", symbol.filename().unwrap().display(), symbol.lineno().unwrap(), col);
- } else {
- // Windows debug symbols don't support column numbers, so fall back to
- // line numbers only if no `colno` is available
- return format!("{}:{}", symbol.filename().unwrap().display(), symbol.lineno().unwrap());
- }
- }
- } else { found_debug_sync = true; }
- }
- }
- panic!("Couldn't find mutex construction callsite");
-}
-
-impl LockMetadata {
- fn new() -> Arc<LockMetadata> {
- let backtrace = Backtrace::new();
- let lock_idx = LOCK_IDX.fetch_add(1, Ordering::Relaxed) as u64;
-
- let res = Arc::new(LockMetadata {
- locked_before: StdMutex::new(HashMap::new()),
- lock_idx,
- _lock_construction_bt: backtrace,
- });
-
- #[cfg(feature = "backtrace")]
- {
- let lock_constr_location = get_construction_location(&res._lock_construction_bt);
- LOCKS_INIT.call_once(|| { unsafe { LOCKS = Some(StdMutex::new(HashMap::new())); } });
- let mut locks = unsafe { LOCKS.as_ref() }.unwrap().lock().unwrap();
- match locks.entry(lock_constr_location) {
- hash_map::Entry::Occupied(e) => return Arc::clone(e.get()),
- hash_map::Entry::Vacant(e) => { e.insert(Arc::clone(&res)); },
- }
- }
- res
- }
-
- // Returns whether we were a recursive lock (only relevant for read)
- fn _pre_lock(this: &Arc<LockMetadata>, read: bool) -> bool {
- let mut inserted = false;
- LOCKS_HELD.with(|held| {
- // For each lock which is currently locked, check that no lock's locked-before
- // set includes the lock we're about to lock, which would imply a lockorder
- // inversion.
- for (locked_idx, _locked) in held.borrow().iter() {
- if read && *locked_idx == this.lock_idx {
- // Recursive read locks are explicitly allowed
- return;
- }
- }
- for (locked_idx, locked) in held.borrow().iter() {
- if !read && *locked_idx == this.lock_idx {
- // With `feature = "backtrace"` set, we may be looking at different instances
- // of the same lock.
- debug_assert!(cfg!(feature = "backtrace"), "Tried to acquire a lock while it was held!");
- }
- for (locked_dep_idx, _locked_dep) in locked.locked_before.lock().unwrap().iter() {
- if *locked_dep_idx == this.lock_idx && *locked_dep_idx != locked.lock_idx {
- #[cfg(feature = "backtrace")]
- panic!("Tried to violate existing lockorder.\nMutex that should be locked after the current lock was created at the following backtrace.\nNote that to get a backtrace for the lockorder violation, you should set RUST_BACKTRACE=1\nLock being taken constructed at: {} ({}):\n{:?}\nLock constructed at: {} ({})\n{:?}\n\nLock dep created at:\n{:?}\n\n",
- get_construction_location(&this._lock_construction_bt), this.lock_idx, this._lock_construction_bt,
- get_construction_location(&locked._lock_construction_bt), locked.lock_idx, locked._lock_construction_bt,
- _locked_dep._lockdep_trace);
- #[cfg(not(feature = "backtrace"))]
- panic!("Tried to violate existing lockorder. Build with the backtrace feature for more info.");
- }
- }
- // Insert any already-held locks in our locked-before set.
- let mut locked_before = this.locked_before.lock().unwrap();
- if !locked_before.contains_key(&locked.lock_idx) {
- let lockdep = LockDep { lock: Arc::clone(locked), _lockdep_trace: Backtrace::new() };
- locked_before.insert(lockdep.lock.lock_idx, lockdep);
- }
- }
- held.borrow_mut().insert(this.lock_idx, Arc::clone(this));
- inserted = true;
- });
- inserted
- }
-
- fn pre_lock(this: &Arc<LockMetadata>) { Self::_pre_lock(this, false); }
- fn pre_read_lock(this: &Arc<LockMetadata>) -> bool { Self::_pre_lock(this, true) }
-
- fn try_locked(this: &Arc<LockMetadata>) {
- LOCKS_HELD.with(|held| {
- // Since a try-lock will simply fail if the lock is held already, we do not
- // consider try-locks to ever generate lockorder inversions. However, if a try-lock
- // succeeds, we do consider it to have created lockorder dependencies.
- let mut locked_before = this.locked_before.lock().unwrap();
- for (locked_idx, locked) in held.borrow().iter() {
- if !locked_before.contains_key(locked_idx) {
- let lockdep = LockDep { lock: Arc::clone(locked), _lockdep_trace: Backtrace::new() };
- locked_before.insert(*locked_idx, lockdep);
- }
- }
- held.borrow_mut().insert(this.lock_idx, Arc::clone(this));
- });
- }
-}
-
-pub struct Mutex<T: Sized> {
- inner: StdMutex<T>,
- deps: Arc<LockMetadata>,
-}
-
-#[must_use = "if unused the Mutex will immediately unlock"]
-pub struct MutexGuard<'a, T: Sized + 'a> {
- mutex: &'a Mutex<T>,
- lock: StdMutexGuard<'a, T>,
-}
-
-impl<'a, T: Sized> MutexGuard<'a, T> {
- fn into_inner(self) -> StdMutexGuard<'a, T> {
- // Somewhat unclear why we cannot move out of self.lock, but doing so gets E0509.
- unsafe {
- let v: StdMutexGuard<'a, T> = std::ptr::read(&self.lock);
- std::mem::forget(self);
- v
- }
- }
-}
-
-impl<T: Sized> Drop for MutexGuard<'_, T> {
- fn drop(&mut self) {
- LOCKS_HELD.with(|held| {
- held.borrow_mut().remove(&self.mutex.deps.lock_idx);
- });
- }
-}
-
-impl<T: Sized> Deref for MutexGuard<'_, T> {
- type Target = T;
-
- fn deref(&self) -> &T {
- &self.lock.deref()
- }
-}
-
-impl<T: Sized> DerefMut for MutexGuard<'_, T> {
- fn deref_mut(&mut self) -> &mut T {
- self.lock.deref_mut()
- }
-}
-
-impl<T> Mutex<T> {
- pub fn new(inner: T) -> Mutex<T> {
- Mutex { inner: StdMutex::new(inner), deps: LockMetadata::new() }
- }
-
- pub fn lock<'a>(&'a self) -> LockResult<MutexGuard<'a, T>> {
- LockMetadata::pre_lock(&self.deps);
- self.inner.lock().map(|lock| MutexGuard { mutex: self, lock }).map_err(|_| ())
- }
-
- pub fn try_lock<'a>(&'a self) -> LockResult<MutexGuard<'a, T>> {
- let res = self.inner.try_lock().map(|lock| MutexGuard { mutex: self, lock }).map_err(|_| ());
- if res.is_ok() {
- LockMetadata::try_locked(&self.deps);
- }
- res
- }
-}
-
-pub struct RwLock<T: Sized> {
- inner: StdRwLock<T>,
- deps: Arc<LockMetadata>,
-}
-
-pub struct RwLockReadGuard<'a, T: Sized + 'a> {
- lock: &'a RwLock<T>,
- first_lock: bool,
- guard: StdRwLockReadGuard<'a, T>,
-}
-
-pub struct RwLockWriteGuard<'a, T: Sized + 'a> {
- lock: &'a RwLock<T>,
- guard: StdRwLockWriteGuard<'a, T>,
-}
-
-impl<T: Sized> Deref for RwLockReadGuard<'_, T> {
- type Target = T;
-
- fn deref(&self) -> &T {
- &self.guard.deref()
- }
-}
-
-impl<T: Sized> Drop for RwLockReadGuard<'_, T> {
- fn drop(&mut self) {
- if !self.first_lock {
- // Note that its not strictly true that the first taken read lock will get unlocked
- // last, but in practice our locks are always taken as RAII, so it should basically
- // always be true.
- return;
- }
- LOCKS_HELD.with(|held| {
- held.borrow_mut().remove(&self.lock.deps.lock_idx);
- });
- }
-}
-
-impl<T: Sized> Deref for RwLockWriteGuard<'_, T> {
- type Target = T;
-
- fn deref(&self) -> &T {
- &self.guard.deref()
- }
-}
-
-impl<T: Sized> Drop for RwLockWriteGuard<'_, T> {
- fn drop(&mut self) {
- LOCKS_HELD.with(|held| {
- held.borrow_mut().remove(&self.lock.deps.lock_idx);
- });
- }
-}
-
-impl<T: Sized> DerefMut for RwLockWriteGuard<'_, T> {
- fn deref_mut(&mut self) -> &mut T {
- self.guard.deref_mut()
- }
-}
-
-impl<T> RwLock<T> {
- pub fn new(inner: T) -> RwLock<T> {
- RwLock { inner: StdRwLock::new(inner), deps: LockMetadata::new() }
- }
-
- pub fn read<'a>(&'a self) -> LockResult<RwLockReadGuard<'a, T>> {
- let first_lock = LockMetadata::pre_read_lock(&self.deps);
- self.inner.read().map(|guard| RwLockReadGuard { lock: self, guard, first_lock }).map_err(|_| ())
- }
-
- pub fn write<'a>(&'a self) -> LockResult<RwLockWriteGuard<'a, T>> {
- LockMetadata::pre_lock(&self.deps);
- self.inner.write().map(|guard| RwLockWriteGuard { lock: self, guard }).map_err(|_| ())
- }
-
- pub fn try_write<'a>(&'a self) -> LockResult<RwLockWriteGuard<'a, T>> {
- let res = self.inner.try_write().map(|guard| RwLockWriteGuard { lock: self, guard }).map_err(|_| ());
- if res.is_ok() {
- LockMetadata::try_locked(&self.deps);
- }
- res
- }
-}
-
-pub type FairRwLock<T> = RwLock<T>;
-
-mod tests {
- use super::{RwLock, Mutex};
-
- #[test]
- #[should_panic]
- #[cfg(not(feature = "backtrace"))]
- fn recursive_lock_fail() {
- let mutex = Mutex::new(());
- let _a = mutex.lock().unwrap();
- let _b = mutex.lock().unwrap();
- }
-
- #[test]
- fn recursive_read() {
- let lock = RwLock::new(());
- let _a = lock.read().unwrap();
- let _b = lock.read().unwrap();
- }
-
- #[test]
- #[should_panic]
- fn lockorder_fail() {
- let a = Mutex::new(());
- let b = Mutex::new(());
- {
- let _a = a.lock().unwrap();
- let _b = b.lock().unwrap();
- }
- {
- let _b = b.lock().unwrap();
- let _a = a.lock().unwrap();
- }
- }
-
- #[test]
- #[should_panic]
- fn write_lockorder_fail() {
- let a = RwLock::new(());
- let b = RwLock::new(());
- {
- let _a = a.write().unwrap();
- let _b = b.write().unwrap();
- }
- {
- let _b = b.write().unwrap();
- let _a = a.write().unwrap();
- }
- }
-
- #[test]
- #[should_panic]
- fn read_lockorder_fail() {
- let a = RwLock::new(());
- let b = RwLock::new(());
- {
- let _a = a.read().unwrap();
- let _b = b.read().unwrap();
- }
- {
- let _b = b.read().unwrap();
- let _a = a.read().unwrap();
- }
- }
-
- #[test]
- fn read_recursive_no_lockorder() {
- // Like the above, but note that no lockorder is implied when we recursively read-lock a
- // RwLock, causing this to pass just fine.
- let a = RwLock::new(());
- let b = RwLock::new(());
- let _outer = a.read().unwrap();
- {
- let _a = a.read().unwrap();
- let _b = b.read().unwrap();
- }
- {
- let _b = b.read().unwrap();
- let _a = a.read().unwrap();
- }
- }
-
- #[test]
- #[should_panic]
- fn read_write_lockorder_fail() {
- let a = RwLock::new(());
- let b = RwLock::new(());
- {
- let _a = a.write().unwrap();
- let _b = b.read().unwrap();
- }
- {
- let _b = b.read().unwrap();
- let _a = a.write().unwrap();
- }
- }
-}
pub use alloc::string::ToString;
}
-#[cfg(all(not(feature = "_bench_unstable"), feature = "std", test))]
-mod debug_sync;
#[cfg(all(not(feature = "_bench_unstable"), feature = "backtrace", feature = "std", test))]
extern crate backtrace;
--- /dev/null
+pub use ::alloc::sync::Arc;
+use core::ops::{Deref, DerefMut};
+use core::time::Duration;
+
+use std::cell::RefCell;
+
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::Mutex as StdMutex;
+use std::sync::MutexGuard as StdMutexGuard;
+use std::sync::RwLock as StdRwLock;
+use std::sync::RwLockReadGuard as StdRwLockReadGuard;
+use std::sync::RwLockWriteGuard as StdRwLockWriteGuard;
+use std::sync::Condvar as StdCondvar;
+
+use crate::prelude::HashMap;
+
+#[cfg(feature = "backtrace")]
+use {crate::prelude::hash_map, backtrace::Backtrace, std::sync::Once};
+
+#[cfg(not(feature = "backtrace"))]
+struct Backtrace{}
+#[cfg(not(feature = "backtrace"))]
+impl Backtrace { fn new() -> Backtrace { Backtrace {} } }
+
+pub type LockResult<Guard> = Result<Guard, ()>;
+
+pub struct Condvar {
+ inner: StdCondvar,
+}
+
+impl Condvar {
+ pub fn new() -> Condvar {
+ Condvar { inner: StdCondvar::new() }
+ }
+
+ pub fn wait<'a, T>(&'a self, guard: MutexGuard<'a, T>) -> LockResult<MutexGuard<'a, T>> {
+ let mutex: &'a Mutex<T> = guard.mutex;
+ self.inner.wait(guard.into_inner()).map(|lock| MutexGuard { mutex, lock }).map_err(|_| ())
+ }
+
+ #[allow(unused)]
+ pub fn wait_timeout<'a, T>(&'a self, guard: MutexGuard<'a, T>, dur: Duration) -> LockResult<(MutexGuard<'a, T>, ())> {
+ let mutex = guard.mutex;
+ self.inner.wait_timeout(guard.into_inner(), dur).map(|(lock, _)| (MutexGuard { mutex, lock }, ())).map_err(|_| ())
+ }
+
+ pub fn notify_all(&self) { self.inner.notify_all(); }
+}
+
+thread_local! {
+ /// We track the set of locks currently held by a reference to their `LockMetadata`
+ static LOCKS_HELD: RefCell<HashMap<u64, Arc<LockMetadata>>> = RefCell::new(HashMap::new());
+}
+static LOCK_IDX: AtomicUsize = AtomicUsize::new(0);
+
+#[cfg(feature = "backtrace")]
+static mut LOCKS: Option<StdMutex<HashMap<String, Arc<LockMetadata>>>> = None;
+#[cfg(feature = "backtrace")]
+static LOCKS_INIT: Once = Once::new();
+
+/// Metadata about a single lock, by id, the set of things locked-before it, and the backtrace of
+/// when the Mutex itself was constructed.
+struct LockMetadata {
+ lock_idx: u64,
+ locked_before: StdMutex<HashMap<u64, LockDep>>,
+ _lock_construction_bt: Backtrace,
+}
+
+struct LockDep {
+ lock: Arc<LockMetadata>,
+ /// lockdep_trace is unused unless we're building with `backtrace`, so we mark it _
+ _lockdep_trace: Backtrace,
+}
+
+#[cfg(feature = "backtrace")]
+fn get_construction_location(backtrace: &Backtrace) -> String {
+ // Find the first frame that is after `debug_sync` (or that is in our tests) and use
+ // that as the mutex construction site. Note that the first few frames may be in
+ // the `backtrace` crate, so we have to ignore those.
+ let sync_mutex_constr_regex = regex::Regex::new(r"lightning.*debug_sync.*new").unwrap();
+ let mut found_debug_sync = false;
+ for frame in backtrace.frames() {
+ for symbol in frame.symbols() {
+ let symbol_name = symbol.name().unwrap().as_str().unwrap();
+ if !sync_mutex_constr_regex.is_match(symbol_name) {
+ if found_debug_sync {
+ if let Some(col) = symbol.colno() {
+ return format!("{}:{}:{}", symbol.filename().unwrap().display(), symbol.lineno().unwrap(), col);
+ } else {
+ // Windows debug symbols don't support column numbers, so fall back to
+ // line numbers only if no `colno` is available
+ return format!("{}:{}", symbol.filename().unwrap().display(), symbol.lineno().unwrap());
+ }
+ }
+ } else { found_debug_sync = true; }
+ }
+ }
+ panic!("Couldn't find mutex construction callsite");
+}
+
+impl LockMetadata {
+ fn new() -> Arc<LockMetadata> {
+ let backtrace = Backtrace::new();
+ let lock_idx = LOCK_IDX.fetch_add(1, Ordering::Relaxed) as u64;
+
+ let res = Arc::new(LockMetadata {
+ locked_before: StdMutex::new(HashMap::new()),
+ lock_idx,
+ _lock_construction_bt: backtrace,
+ });
+
+ #[cfg(feature = "backtrace")]
+ {
+ let lock_constr_location = get_construction_location(&res._lock_construction_bt);
+ LOCKS_INIT.call_once(|| { unsafe { LOCKS = Some(StdMutex::new(HashMap::new())); } });
+ let mut locks = unsafe { LOCKS.as_ref() }.unwrap().lock().unwrap();
+ match locks.entry(lock_constr_location) {
+ hash_map::Entry::Occupied(e) => return Arc::clone(e.get()),
+ hash_map::Entry::Vacant(e) => { e.insert(Arc::clone(&res)); },
+ }
+ }
+ res
+ }
+
+ // Returns whether we were a recursive lock (only relevant for read)
+ fn _pre_lock(this: &Arc<LockMetadata>, read: bool) -> bool {
+ let mut inserted = false;
+ LOCKS_HELD.with(|held| {
+ // For each lock which is currently locked, check that no lock's locked-before
+ // set includes the lock we're about to lock, which would imply a lockorder
+ // inversion.
+ for (locked_idx, _locked) in held.borrow().iter() {
+ if read && *locked_idx == this.lock_idx {
+ // Recursive read locks are explicitly allowed
+ return;
+ }
+ }
+ for (locked_idx, locked) in held.borrow().iter() {
+ if !read && *locked_idx == this.lock_idx {
+ // With `feature = "backtrace"` set, we may be looking at different instances
+ // of the same lock.
+ debug_assert!(cfg!(feature = "backtrace"), "Tried to acquire a lock while it was held!");
+ }
+ for (locked_dep_idx, _locked_dep) in locked.locked_before.lock().unwrap().iter() {
+ if *locked_dep_idx == this.lock_idx && *locked_dep_idx != locked.lock_idx {
+ #[cfg(feature = "backtrace")]
+ panic!("Tried to violate existing lockorder.\nMutex that should be locked after the current lock was created at the following backtrace.\nNote that to get a backtrace for the lockorder violation, you should set RUST_BACKTRACE=1\nLock being taken constructed at: {} ({}):\n{:?}\nLock constructed at: {} ({})\n{:?}\n\nLock dep created at:\n{:?}\n\n",
+ get_construction_location(&this._lock_construction_bt), this.lock_idx, this._lock_construction_bt,
+ get_construction_location(&locked._lock_construction_bt), locked.lock_idx, locked._lock_construction_bt,
+ _locked_dep._lockdep_trace);
+ #[cfg(not(feature = "backtrace"))]
+ panic!("Tried to violate existing lockorder. Build with the backtrace feature for more info.");
+ }
+ }
+ // Insert any already-held locks in our locked-before set.
+ let mut locked_before = this.locked_before.lock().unwrap();
+ if !locked_before.contains_key(&locked.lock_idx) {
+ let lockdep = LockDep { lock: Arc::clone(locked), _lockdep_trace: Backtrace::new() };
+ locked_before.insert(lockdep.lock.lock_idx, lockdep);
+ }
+ }
+ held.borrow_mut().insert(this.lock_idx, Arc::clone(this));
+ inserted = true;
+ });
+ inserted
+ }
+
+ fn pre_lock(this: &Arc<LockMetadata>) { Self::_pre_lock(this, false); }
+ fn pre_read_lock(this: &Arc<LockMetadata>) -> bool { Self::_pre_lock(this, true) }
+
+ fn try_locked(this: &Arc<LockMetadata>) {
+ LOCKS_HELD.with(|held| {
+ // Since a try-lock will simply fail if the lock is held already, we do not
+ // consider try-locks to ever generate lockorder inversions. However, if a try-lock
+ // succeeds, we do consider it to have created lockorder dependencies.
+ let mut locked_before = this.locked_before.lock().unwrap();
+ for (locked_idx, locked) in held.borrow().iter() {
+ if !locked_before.contains_key(locked_idx) {
+ let lockdep = LockDep { lock: Arc::clone(locked), _lockdep_trace: Backtrace::new() };
+ locked_before.insert(*locked_idx, lockdep);
+ }
+ }
+ held.borrow_mut().insert(this.lock_idx, Arc::clone(this));
+ });
+ }
+}
+
+pub struct Mutex<T: Sized> {
+ inner: StdMutex<T>,
+ deps: Arc<LockMetadata>,
+}
+
+#[must_use = "if unused the Mutex will immediately unlock"]
+pub struct MutexGuard<'a, T: Sized + 'a> {
+ mutex: &'a Mutex<T>,
+ lock: StdMutexGuard<'a, T>,
+}
+
+impl<'a, T: Sized> MutexGuard<'a, T> {
+ fn into_inner(self) -> StdMutexGuard<'a, T> {
+ // Somewhat unclear why we cannot move out of self.lock, but doing so gets E0509.
+ unsafe {
+ let v: StdMutexGuard<'a, T> = std::ptr::read(&self.lock);
+ std::mem::forget(self);
+ v
+ }
+ }
+}
+
+impl<T: Sized> Drop for MutexGuard<'_, T> {
+ fn drop(&mut self) {
+ LOCKS_HELD.with(|held| {
+ held.borrow_mut().remove(&self.mutex.deps.lock_idx);
+ });
+ }
+}
+
+impl<T: Sized> Deref for MutexGuard<'_, T> {
+ type Target = T;
+
+ fn deref(&self) -> &T {
+ &self.lock.deref()
+ }
+}
+
+impl<T: Sized> DerefMut for MutexGuard<'_, T> {
+ fn deref_mut(&mut self) -> &mut T {
+ self.lock.deref_mut()
+ }
+}
+
+impl<T> Mutex<T> {
+ pub fn new(inner: T) -> Mutex<T> {
+ Mutex { inner: StdMutex::new(inner), deps: LockMetadata::new() }
+ }
+
+ pub fn lock<'a>(&'a self) -> LockResult<MutexGuard<'a, T>> {
+ LockMetadata::pre_lock(&self.deps);
+ self.inner.lock().map(|lock| MutexGuard { mutex: self, lock }).map_err(|_| ())
+ }
+
+ pub fn try_lock<'a>(&'a self) -> LockResult<MutexGuard<'a, T>> {
+ let res = self.inner.try_lock().map(|lock| MutexGuard { mutex: self, lock }).map_err(|_| ());
+ if res.is_ok() {
+ LockMetadata::try_locked(&self.deps);
+ }
+ res
+ }
+}
+
+pub struct RwLock<T: Sized> {
+ inner: StdRwLock<T>,
+ deps: Arc<LockMetadata>,
+}
+
+pub struct RwLockReadGuard<'a, T: Sized + 'a> {
+ lock: &'a RwLock<T>,
+ first_lock: bool,
+ guard: StdRwLockReadGuard<'a, T>,
+}
+
+pub struct RwLockWriteGuard<'a, T: Sized + 'a> {
+ lock: &'a RwLock<T>,
+ guard: StdRwLockWriteGuard<'a, T>,
+}
+
+impl<T: Sized> Deref for RwLockReadGuard<'_, T> {
+ type Target = T;
+
+ fn deref(&self) -> &T {
+ &self.guard.deref()
+ }
+}
+
+impl<T: Sized> Drop for RwLockReadGuard<'_, T> {
+ fn drop(&mut self) {
+ if !self.first_lock {
+ // Note that its not strictly true that the first taken read lock will get unlocked
+ // last, but in practice our locks are always taken as RAII, so it should basically
+ // always be true.
+ return;
+ }
+ LOCKS_HELD.with(|held| {
+ held.borrow_mut().remove(&self.lock.deps.lock_idx);
+ });
+ }
+}
+
+impl<T: Sized> Deref for RwLockWriteGuard<'_, T> {
+ type Target = T;
+
+ fn deref(&self) -> &T {
+ &self.guard.deref()
+ }
+}
+
+impl<T: Sized> Drop for RwLockWriteGuard<'_, T> {
+ fn drop(&mut self) {
+ LOCKS_HELD.with(|held| {
+ held.borrow_mut().remove(&self.lock.deps.lock_idx);
+ });
+ }
+}
+
+impl<T: Sized> DerefMut for RwLockWriteGuard<'_, T> {
+ fn deref_mut(&mut self) -> &mut T {
+ self.guard.deref_mut()
+ }
+}
+
+impl<T> RwLock<T> {
+ pub fn new(inner: T) -> RwLock<T> {
+ RwLock { inner: StdRwLock::new(inner), deps: LockMetadata::new() }
+ }
+
+ pub fn read<'a>(&'a self) -> LockResult<RwLockReadGuard<'a, T>> {
+ let first_lock = LockMetadata::pre_read_lock(&self.deps);
+ self.inner.read().map(|guard| RwLockReadGuard { lock: self, guard, first_lock }).map_err(|_| ())
+ }
+
+ pub fn write<'a>(&'a self) -> LockResult<RwLockWriteGuard<'a, T>> {
+ LockMetadata::pre_lock(&self.deps);
+ self.inner.write().map(|guard| RwLockWriteGuard { lock: self, guard }).map_err(|_| ())
+ }
+
+ pub fn try_write<'a>(&'a self) -> LockResult<RwLockWriteGuard<'a, T>> {
+ let res = self.inner.try_write().map(|guard| RwLockWriteGuard { lock: self, guard }).map_err(|_| ());
+ if res.is_ok() {
+ LockMetadata::try_locked(&self.deps);
+ }
+ res
+ }
+}
+
+pub type FairRwLock<T> = RwLock<T>;
+
+mod tests {
+ use super::{RwLock, Mutex};
+
+ #[test]
+ #[should_panic]
+ #[cfg(not(feature = "backtrace"))]
+ fn recursive_lock_fail() {
+ let mutex = Mutex::new(());
+ let _a = mutex.lock().unwrap();
+ let _b = mutex.lock().unwrap();
+ }
+
+ #[test]
+ fn recursive_read() {
+ let lock = RwLock::new(());
+ let _a = lock.read().unwrap();
+ let _b = lock.read().unwrap();
+ }
+
+ #[test]
+ #[should_panic]
+ fn lockorder_fail() {
+ let a = Mutex::new(());
+ let b = Mutex::new(());
+ {
+ let _a = a.lock().unwrap();
+ let _b = b.lock().unwrap();
+ }
+ {
+ let _b = b.lock().unwrap();
+ let _a = a.lock().unwrap();
+ }
+ }
+
+ #[test]
+ #[should_panic]
+ fn write_lockorder_fail() {
+ let a = RwLock::new(());
+ let b = RwLock::new(());
+ {
+ let _a = a.write().unwrap();
+ let _b = b.write().unwrap();
+ }
+ {
+ let _b = b.write().unwrap();
+ let _a = a.write().unwrap();
+ }
+ }
+
+ #[test]
+ #[should_panic]
+ fn read_lockorder_fail() {
+ let a = RwLock::new(());
+ let b = RwLock::new(());
+ {
+ let _a = a.read().unwrap();
+ let _b = b.read().unwrap();
+ }
+ {
+ let _b = b.read().unwrap();
+ let _a = a.read().unwrap();
+ }
+ }
+
+ #[test]
+ fn read_recursive_no_lockorder() {
+ // Like the above, but note that no lockorder is implied when we recursively read-lock a
+ // RwLock, causing this to pass just fine.
+ let a = RwLock::new(());
+ let b = RwLock::new(());
+ let _outer = a.read().unwrap();
+ {
+ let _a = a.read().unwrap();
+ let _b = b.read().unwrap();
+ }
+ {
+ let _b = b.read().unwrap();
+ let _a = a.read().unwrap();
+ }
+ }
+
+ #[test]
+ #[should_panic]
+ fn read_write_lockorder_fail() {
+ let a = RwLock::new(());
+ let b = RwLock::new(());
+ {
+ let _a = a.write().unwrap();
+ let _b = b.read().unwrap();
+ }
+ {
+ let _b = b.read().unwrap();
+ let _a = a.write().unwrap();
+ }
+ }
+}
#[cfg(all(feature = "std", not(feature = "_bench_unstable"), test))]
-pub use crate::debug_sync::*;
+mod debug_sync;
+#[cfg(all(feature = "std", not(feature = "_bench_unstable"), test))]
+pub use debug_sync::*;
+
#[cfg(all(feature = "std", any(feature = "_bench_unstable", not(test))))]
pub use ::std::sync::{Arc, Mutex, Condvar, MutexGuard, RwLock, RwLockReadGuard, RwLockWriteGuard};
#[cfg(all(feature = "std", any(feature = "_bench_unstable", not(test))))]
projects / rust-lightning / commitdiff