itsscb/sqlx
1
0
Fork 0
mirror of https://github.com/launchbadge/sqlx.git synced 2025-12-29 21:00:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

chore: delete defunct use of futures-intrusive

Browse Source
This commit is contained in:
Austin Bonander 2024-11-08 17:05:19 -08:00
parent e210a23b72
commit 0fb9ab12bb
1 changed files with 4 additions and 199 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

203
sqlx-core/src/sync.rs
View File

@ -1,206 +1,11 @@
use cfg_if::cfg_if;
// For types with identical signatures that don't require runtime support,
// we can just arbitrarily pick one to use based on what's enabled.
//
// We'll generally lean towards Tokio's types as those are more featureful
// (including `tokio-console` support) and more widely deployed.
pub struct AsyncSemaphore {
// We use the semaphore from futures-intrusive as the one from async-lock
// is missing the ability to add arbitrary permits, and is not guaranteed to be fair:
// * https://github.com/smol-rs/async-lock/issues/22
// * https://github.com/smol-rs/async-lock/issues/23
//
// We're on the look-out for a replacement, however, as futures-intrusive is not maintained
// and there are some soundness concerns (although it turns out any intrusive future is unsound
// in MIRI due to the necessitated mutable aliasing):
// https://github.com/launchbadge/sqlx/issues/1668
#[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))]
inner: futures_intrusive::sync::Semaphore,
#[cfg(all(feature = "_rt-async-std", not(feature = "_rt-tokio")))]
pub use async_std::sync::{Mutex as AsyncMutex, MutexGuard as AsyncMutexGuard};
#[cfg(feature = "_rt-tokio")]
inner: tokio::sync::Semaphore,
}
impl AsyncSemaphore {
#[track_caller]
pub fn new(fair: bool, permits: usize) -> Self {
if cfg!(not(any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol",
feature = "_rt-tokio"
))) {
crate::rt::missing_rt((fair, permits));
}
AsyncSemaphore {
#[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))]
inner: futures_intrusive::sync::Semaphore::new(fair, permits),
#[cfg(feature = "_rt-tokio")]
inner: {
debug_assert!(fair, "Tokio only has fair permits");
tokio::sync::Semaphore::new(permits)
},
}
}
pub fn permits(&self) -> usize {
cfg_if! {
if #[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))] {
self.inner.permits()
} else if #[cfg(feature = "_rt-tokio")] {
self.inner.available_permits()
} else {
crate::rt::missing_rt(())
}
}
}
pub async fn acquire(&self, permits: u32) -> AsyncSemaphoreReleaser<'_> {
cfg_if! {
if #[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))] {
AsyncSemaphoreReleaser {
inner: self.inner.acquire(permits as usize).await,
}
} else if #[cfg(feature = "_rt-tokio")] {
AsyncSemaphoreReleaser {
inner: self
.inner
// Weird quirk: `tokio::sync::Semaphore` mostly uses `usize` for permit counts,
// but `u32` for this and `try_acquire_many()`.
.acquire_many(permits)
.await
.expect("BUG: we do not expose the `.close()` method"),
}
} else {
crate::rt::missing_rt(permits)
}
}
}
pub fn try_acquire(&self, permits: u32) -> Option<AsyncSemaphoreReleaser<'_>> {
cfg_if! {
if #[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))] {
Some(AsyncSemaphoreReleaser {
inner: self.inner.try_acquire(permits as usize)?,
})
} else if #[cfg(feature = "_rt-tokio")] {
Some(AsyncSemaphoreReleaser {
inner: self.inner.try_acquire_many(permits).ok()?,
})
} else {
crate::rt::missing_rt(permits)
}
}
}
pub fn release(&self, permits: usize) {
cfg_if! {
if #[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))] {
self.inner.release(permits);
} else if #[cfg(feature = "_rt-tokio")] {
self.inner.add_permits(permits);
} else {
crate::rt::missing_rt(permits);
}
}
}
}
pub struct AsyncSemaphoreReleaser<'a> {
// We use the semaphore from futures-intrusive as the one from async-std
// is missing the ability to add arbitrary permits, and is not guaranteed to be fair:
// * https://github.com/smol-rs/async-lock/issues/22
// * https://github.com/smol-rs/async-lock/issues/23
//
// We're on the look-out for a replacement, however, as futures-intrusive is not maintained
// and there are some soundness concerns (although it turns out any intrusive future is unsound
// in MIRI due to the necessitated mutable aliasing):
// https://github.com/launchbadge/sqlx/issues/1668
#[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))]
inner: futures_intrusive::sync::SemaphoreReleaser<'a>,
#[cfg(feature = "_rt-tokio")]
inner: tokio::sync::SemaphorePermit<'a>,
#[cfg(not(any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol",
feature = "_rt-tokio"
)))]
_phantom: std::marker::PhantomData<&'a ()>,
}
impl AsyncSemaphoreReleaser<'_> {
pub fn disarm(self) {
cfg_if! {
if #[cfg(all(
any(
feature = "_rt-async-global-executor",
feature = "_rt-async-std",
feature = "_rt-smol"
),
not(feature = "_rt-tokio")
))] {
let mut this = self;
this.inner.disarm();
} else if #[cfg(feature = "_rt-tokio")] {
self.inner.forget();
} else {
crate::rt::missing_rt(());
}
}
}
}
#[cfg(feature = "_rt-tokio")]
pub use tokio::sync::{Mutex as AsyncMutex, MutexGuard as AsyncMutexGuard};