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Run TLS destructors for wasm32-wasip1-threads

The target has support for pthreads and allows
registration of TLS destructors.
This commit is contained in:
Sebastian Urban 2024-11-23 21:28:09 +01:00
parent 7db7489f9b
commit ec5f41a953
2 changed files with 74 additions and 0 deletions

View file

@ -0,0 +1,71 @@
//! wasm32-wasip1 has pthreads support.
use crate::cell::Cell;
use crate::sync::atomic::{AtomicBool, Ordering};
use crate::sys::thread_local::destructors;
use crate::{ffi, ptr};
// Add a few symbols not in upstream `libc` just yet.
mod libc {
pub use libc::*;
use crate::ffi;
#[allow(non_camel_case_types)]
pub type pthread_key_t = ffi::c_uint;
extern "C" {
pub fn pthread_key_create(
key: *mut pthread_key_t,
destructor: unsafe extern "C" fn(*mut ffi::c_void),
) -> ffi::c_int;
pub fn pthread_setspecific(key: pthread_key_t, value: *const ffi::c_void) -> ffi::c_int;
}
}
pub fn enable() {
enable_main();
enable_thread();
}
fn enable_main() {
static REGISTERED: AtomicBool = AtomicBool::new(false);
if !REGISTERED.swap(true, Ordering::AcqRel) {
unsafe {
assert_eq!(libc::atexit(run_main_dtors), 0);
}
}
extern "C" fn run_main_dtors() {
unsafe {
destructors::run();
crate::rt::thread_cleanup();
}
}
}
fn enable_thread() {
#[thread_local]
static REGISTERED: Cell<bool> = Cell::new(false);
if !REGISTERED.replace(true) {
unsafe {
let mut key: libc::pthread_key_t = 0;
assert_eq!(libc::pthread_key_create(&mut key, run_thread_dtors), 0);
// We must set the value to a non-NULL pointer value so that
// the destructor is run on thread exit. The pointer is only
// passed to run_dtors and never dereferenced.
assert_eq!(libc::pthread_setspecific(key, ptr::without_provenance(1)), 0);
}
}
extern "C" fn run_thread_dtors(_: *mut ffi::c_void) {
unsafe {
destructors::run();
crate::rt::thread_cleanup();
}
}
}

View file

@ -85,6 +85,9 @@ pub(crate) mod guard {
} else if #[cfg(target_os = "windows")] {
mod windows;
pub(crate) use windows::enable;
} else if #[cfg(all(target_os = "wasi"))] {
mod wasi;
pub(crate) use wasi::enable;
} else if #[cfg(any(
target_family = "wasm",
target_os = "uefi",