Struct wasmer_compiler::engine::trap::frame_info::FRAME_INFO
source · pub struct FRAME_INFO {
__private_field: (),
}
Expand description
This is a global cache of backtrace frame information for all active
This global cache is used during Trap
creation to symbolicate frames.
This is populated on module compilation, and it is cleared out whenever
all references to a module are dropped.
Fields§
§__private_field: ()
Methods from Deref<Target = RwLock<GlobalFrameInfo>>§
1.0.0 · sourcepub fn read(
&self,
) -> Result<RwLockReadGuard<'_, T>, PoisonError<RwLockReadGuard<'_, T>>>
pub fn read( &self, ) -> Result<RwLockReadGuard<'_, T>, PoisonError<RwLockReadGuard<'_, T>>>
Locks this RwLock
with shared read access, blocking the current thread
until it can be acquired.
The calling thread will be blocked until there are no more writers which hold the lock. There may be other readers currently inside the lock when this method returns. This method does not provide any guarantees with respect to the ordering of whether contentious readers or writers will acquire the lock first.
Returns an RAII guard which will release this thread’s shared access once it is dropped.
§Errors
This function will return an error if the RwLock
is poisoned. An
RwLock
is poisoned whenever a writer panics while holding an exclusive
lock. The failure will occur immediately after the lock has been
acquired.
§Panics
This function might panic when called if the lock is already held by the current thread.
§Examples
use std::sync::{Arc, RwLock};
use std::thread;
let lock = Arc::new(RwLock::new(1));
let c_lock = Arc::clone(&lock);
let n = lock.read().unwrap();
assert_eq!(*n, 1);
thread::spawn(move || {
let r = c_lock.read();
assert!(r.is_ok());
}).join().unwrap();
1.0.0 · sourcepub fn try_read(
&self,
) -> Result<RwLockReadGuard<'_, T>, TryLockError<RwLockReadGuard<'_, T>>>
pub fn try_read( &self, ) -> Result<RwLockReadGuard<'_, T>, TryLockError<RwLockReadGuard<'_, T>>>
Attempts to acquire this RwLock
with shared read access.
If the access could not be granted at this time, then Err
is returned.
Otherwise, an RAII guard is returned which will release the shared access
when it is dropped.
This function does not block.
This function does not provide any guarantees with respect to the ordering of whether contentious readers or writers will acquire the lock first.
§Errors
This function will return the Poisoned
error if the RwLock
is
poisoned. An RwLock
is poisoned whenever a writer panics while holding
an exclusive lock. Poisoned
will only be returned if the lock would
have otherwise been acquired.
This function will return the WouldBlock
error if the RwLock
could
not be acquired because it was already locked exclusively.
§Examples
use std::sync::RwLock;
let lock = RwLock::new(1);
match lock.try_read() {
Ok(n) => assert_eq!(*n, 1),
Err(_) => unreachable!(),
};
1.0.0 · sourcepub fn write(
&self,
) -> Result<RwLockWriteGuard<'_, T>, PoisonError<RwLockWriteGuard<'_, T>>>
pub fn write( &self, ) -> Result<RwLockWriteGuard<'_, T>, PoisonError<RwLockWriteGuard<'_, T>>>
Locks this RwLock
with exclusive write access, blocking the current
thread until it can be acquired.
This function will not return while other writers or other readers currently have access to the lock.
Returns an RAII guard which will drop the write access of this RwLock
when dropped.
§Errors
This function will return an error if the RwLock
is poisoned. An
RwLock
is poisoned whenever a writer panics while holding an exclusive
lock. An error will be returned when the lock is acquired.
§Panics
This function might panic when called if the lock is already held by the current thread.
§Examples
use std::sync::RwLock;
let lock = RwLock::new(1);
let mut n = lock.write().unwrap();
*n = 2;
assert!(lock.try_read().is_err());
1.0.0 · sourcepub fn try_write(
&self,
) -> Result<RwLockWriteGuard<'_, T>, TryLockError<RwLockWriteGuard<'_, T>>>
pub fn try_write( &self, ) -> Result<RwLockWriteGuard<'_, T>, TryLockError<RwLockWriteGuard<'_, T>>>
Attempts to lock this RwLock
with exclusive write access.
If the lock could not be acquired at this time, then Err
is returned.
Otherwise, an RAII guard is returned which will release the lock when
it is dropped.
This function does not block.
This function does not provide any guarantees with respect to the ordering of whether contentious readers or writers will acquire the lock first.
§Errors
This function will return the Poisoned
error if the RwLock
is
poisoned. An RwLock
is poisoned whenever a writer panics while holding
an exclusive lock. Poisoned
will only be returned if the lock would
have otherwise been acquired.
This function will return the WouldBlock
error if the RwLock
could
not be acquired because it was already locked exclusively.
§Examples
use std::sync::RwLock;
let lock = RwLock::new(1);
let n = lock.read().unwrap();
assert_eq!(*n, 1);
assert!(lock.try_write().is_err());
1.2.0 · sourcepub fn is_poisoned(&self) -> bool
pub fn is_poisoned(&self) -> bool
Determines whether the lock is poisoned.
If another thread is active, the lock can still become poisoned at any
time. You should not trust a false
value for program correctness
without additional synchronization.
§Examples
use std::sync::{Arc, RwLock};
use std::thread;
let lock = Arc::new(RwLock::new(0));
let c_lock = Arc::clone(&lock);
let _ = thread::spawn(move || {
let _lock = c_lock.write().unwrap();
panic!(); // the lock gets poisoned
}).join();
assert_eq!(lock.is_poisoned(), true);
1.77.0 · sourcepub fn clear_poison(&self)
pub fn clear_poison(&self)
Clear the poisoned state from a lock.
If the lock is poisoned, it will remain poisoned until this function is called. This allows recovering from a poisoned state and marking that it has recovered. For example, if the value is overwritten by a known-good value, then the lock can be marked as un-poisoned. Or possibly, the value could be inspected to determine if it is in a consistent state, and if so the poison is removed.
§Examples
use std::sync::{Arc, RwLock};
use std::thread;
let lock = Arc::new(RwLock::new(0));
let c_lock = Arc::clone(&lock);
let _ = thread::spawn(move || {
let _lock = c_lock.write().unwrap();
panic!(); // the lock gets poisoned
}).join();
assert_eq!(lock.is_poisoned(), true);
let guard = lock.write().unwrap_or_else(|mut e| {
**e.get_mut() = 1;
lock.clear_poison();
e.into_inner()
});
assert_eq!(lock.is_poisoned(), false);
assert_eq!(*guard, 1);