luxolus
/
pyo3
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Mark Python::with_pool as safe on stable.

This commit is contained in:
Adam Reichold 2023-06-21 09:12:10 +02:00
parent d7e147509b
commit 4afa994449
1 changed files with 3 additions and 68 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

71
src/marker.rs
View File

@ -947,6 +947,9 @@ impl Python<'_> {
/// it limits the closure to using the new GIL token at the cost of
/// being unable to capture existing GIL-bound references.
///
/// Note that on stable Rust, this API suffers from the same the `SendWrapper` loophole
/// as [`allow_threads`][Self::allow_threads], c.f. the documentation of the [`Ungil`] trait,
///
/// # Examples
///
/// ```rust
@ -989,7 +992,6 @@ impl Python<'_> {
/// });
/// });
/// ```
#[cfg(feature = "nightly")]
#[inline]
pub fn with_pool<F, R>(&self, f: F) -> R
where
@ -1002,73 +1004,6 @@ impl Python<'_> {
f(pool.python())
}
/// Creates a scope using a new pool for managing PyO3's owned references.
///
/// This is a safer alterantive to [`new_pool`][Self::new_pool] as
/// it limits the closure to using the new GIL token at the cost of
/// being unable to capture existing GIL-bound references.
///
/// # Examples
///
/// ```rust
/// # use pyo3::prelude::*;
/// Python::with_gil(|py| {
/// // Some long-running process like a webserver, which never releases the GIL.
/// loop {
/// // Create a new scope, so that PyO3 can clear memory at the end of the loop.
/// unsafe {
/// py.with_pool(|py| {
/// // do stuff...
/// });
/// }
/// # break; // Exit the loop so that doctest terminates!
/// }
/// });
/// ```
///
/// The `Ungil` bound on the closure does prevent hanging on to existing GIL-bound references
///
/// ```compile_fail
/// # use pyo3::prelude::*;
/// # use pyo3::types::PyString;
///
/// Python::with_gil(|py| {
/// let old_str = PyString::new(py, "a message from the past");
///
/// py.with_pool(|_py| {
/// print!("{:?}", old_str);
/// });
/// });
/// ```
///
/// or continuing to use the old GIL token
///
/// ```compile_fail
/// # use pyo3::prelude::*;
///
/// Python::with_gil(|old_py| {
/// old_py.with_pool(|_new_py| {
/// let _none = old_py.None();
/// });
/// });
/// ```
///
/// # Safety
///
/// However, due to the `SendWrapper` loophole describe in the documentation of the [`Ungil`] trait,
/// this is still an unsafe API. Usage that does not involve runtime checking of thread affinity
/// should be practically safe.
#[cfg(not(feature = "nightly"))]
#[inline]
pub unsafe fn with_pool<F, R>(&self, f: F) -> R
where
F: for<'py> FnOnce(Python<'py>) -> R + Ungil,
{
let pool = GILPool::new();
f(pool.python())
}
}
impl<'unbound> Python<'unbound> {