diff options
Diffstat (limited to 'library/std/src/sys/solid/thread_local_dtor.rs')
-rw-r--r-- | library/std/src/sys/solid/thread_local_dtor.rs | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/library/std/src/sys/solid/thread_local_dtor.rs b/library/std/src/sys/solid/thread_local_dtor.rs new file mode 100644 index 000000000..973564570 --- /dev/null +++ b/library/std/src/sys/solid/thread_local_dtor.rs @@ -0,0 +1,50 @@ +#![cfg(target_thread_local)] +#![unstable(feature = "thread_local_internals", issue = "none")] + +// Simplify dtor registration by using a list of destructors. + +use super::{abi, itron::task}; +use crate::cell::Cell; +use crate::ptr; + +#[thread_local] +static DTORS: Cell<*mut List> = Cell::new(ptr::null_mut()); + +type List = Vec<(*mut u8, unsafe extern "C" fn(*mut u8))>; + +pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) { + if DTORS.get().is_null() { + let tid = task::current_task_id_aborting(); + let v: Box<List> = box Vec::new(); + DTORS.set(Box::into_raw(v)); + + // Register `tls_dtor` to make sure the TLS destructors are called + // for tasks created by other means than `std::thread` + unsafe { abi::SOLID_TLS_AddDestructor(tid as i32, tls_dtor) }; + } + + let list: &mut List = unsafe { &mut *DTORS.get() }; + list.push((t, dtor)); +} + +pub unsafe fn run_dtors() { + let ptr = DTORS.get(); + if !ptr.is_null() { + // Swap the destructor list, call all registered destructors, + // and repeat this until the list becomes permanently empty. + while let Some(list) = Some(crate::mem::replace(unsafe { &mut *ptr }, Vec::new())) + .filter(|list| !list.is_empty()) + { + for (ptr, dtor) in list.into_iter() { + unsafe { dtor(ptr) }; + } + } + + // Drop the destructor list + unsafe { Box::from_raw(DTORS.replace(ptr::null_mut())) }; + } +} + +unsafe extern "C" fn tls_dtor(_unused: *mut u8) { + unsafe { run_dtors() }; +} |