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Diffstat (limited to 'src/libstd/sys_common/at_exit_imp.rs')
-rw-r--r--src/libstd/sys_common/at_exit_imp.rs75
1 files changed, 0 insertions, 75 deletions
diff --git a/src/libstd/sys_common/at_exit_imp.rs b/src/libstd/sys_common/at_exit_imp.rs
deleted file mode 100644
index 6b799db856e..00000000000
--- a/src/libstd/sys_common/at_exit_imp.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-//! Implementation of running at_exit routines
-//!
-//! Documentation can be found on the `rt::at_exit` function.
-
-use crate::mem;
-use crate::ptr;
-use crate::sys_common::mutex::Mutex;
-
-type Queue = Vec<Box<dyn FnOnce()>>;
-
-// NB these are specifically not types from `std::sync` as they currently rely
-// on poisoning and this module needs to operate at a lower level than requiring
-// the thread infrastructure to be in place (useful on the borders of
-// initialization/destruction).
-// We never call `LOCK.init()`, so it is UB to attempt to
-// acquire this mutex reentrantly!
-static LOCK: Mutex = Mutex::new();
-static mut QUEUE: *mut Queue = ptr::null_mut();
-
-const DONE: *mut Queue = 1_usize as *mut _;
-
-// The maximum number of times the cleanup routines will be run. While running
-// the at_exit closures new ones may be registered, and this count is the number
-// of times the new closures will be allowed to register successfully. After
-// this number of iterations all new registrations will return `false`.
-const ITERS: usize = 10;
-
-unsafe fn init() -> bool {
-    if QUEUE.is_null() {
-        let state: Box<Queue> = box Vec::new();
-        QUEUE = Box::into_raw(state);
-    } else if QUEUE == DONE {
-        // can't re-init after a cleanup
-        return false;
-    }
-
-    true
-}
-
-pub fn cleanup() {
-    for i in 1..=ITERS {
-        unsafe {
-            let queue = {
-                let _guard = LOCK.lock();
-                mem::replace(&mut QUEUE, if i == ITERS { DONE } else { ptr::null_mut() })
-            };
-
-            // make sure we're not recursively cleaning up
-            assert!(queue != DONE);
-
-            // If we never called init, not need to cleanup!
-            if !queue.is_null() {
-                let queue: Box<Queue> = Box::from_raw(queue);
-                for to_run in *queue {
-                    // We are not holding any lock, so reentrancy is fine.
-                    to_run();
-                }
-            }
-        }
-    }
-}
-
-pub fn push(f: Box<dyn FnOnce()>) -> bool {
-    unsafe {
-        let _guard = LOCK.lock();
-        if init() {
-            // We are just moving `f` around, not calling it.
-            // There is no possibility of reentrancy here.
-            (*QUEUE).push(f);
-            true
-        } else {
-            false
-        }
-    }
-}