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authorVivian Lim <[email protected]>2021-02-06 22:11:59 -0800
committerVivian Lim <[email protected]>2021-02-06 22:11:59 -0800
commit64423f0e34cc4a7d78c15b345b3b8f58243d8286 (patch)
treecc20e2e7f0fc35abf470e20e61d3d48f0d954f3b /ctr-std/src/sys/redox/fast_thread_local.rs
parentSupport libctru 2.0 (diff)
downloadarchived-ctru-rs-64423f0e34cc4a7d78c15b345b3b8f58243d8286.tar.xz
archived-ctru-rs-64423f0e34cc4a7d78c15b345b3b8f58243d8286.zip
Delete ctr-std to use my fork of the rust repo instead
Diffstat (limited to 'ctr-std/src/sys/redox/fast_thread_local.rs')
-rw-r--r--ctr-std/src/sys/redox/fast_thread_local.rs121
1 files changed, 0 insertions, 121 deletions
diff --git a/ctr-std/src/sys/redox/fast_thread_local.rs b/ctr-std/src/sys/redox/fast_thread_local.rs
deleted file mode 100644
index 6a007e9..0000000
--- a/ctr-std/src/sys/redox/fast_thread_local.rs
+++ /dev/null
@@ -1,121 +0,0 @@
-// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#![cfg(target_thread_local)]
-#![unstable(feature = "thread_local_internals", issue = "0")]
-
-use cell::{Cell, UnsafeCell};
-use mem;
-use ptr;
-
-
-pub struct Key<T> {
- inner: UnsafeCell<Option<T>>,
-
- // Metadata to keep track of the state of the destructor. Remember that
- // these variables are thread-local, not global.
- dtor_registered: Cell<bool>,
- dtor_running: Cell<bool>,
-}
-
-unsafe impl<T> ::marker::Sync for Key<T> { }
-
-impl<T> Key<T> {
- pub const fn new() -> Key<T> {
- Key {
- inner: UnsafeCell::new(None),
- dtor_registered: Cell::new(false),
- dtor_running: Cell::new(false)
- }
- }
-
- pub fn get(&'static self) -> Option<&'static UnsafeCell<Option<T>>> {
- unsafe {
- if mem::needs_drop::<T>() && self.dtor_running.get() {
- return None
- }
- self.register_dtor();
- }
- Some(&self.inner)
- }
-
- unsafe fn register_dtor(&self) {
- if !mem::needs_drop::<T>() || self.dtor_registered.get() {
- return
- }
-
- register_dtor(self as *const _ as *mut u8,
- destroy_value::<T>);
- self.dtor_registered.set(true);
- }
-}
-
-pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern fn(*mut u8)) {
- // The fallback implementation uses a vanilla OS-based TLS key to track
- // the list of destructors that need to be run for this thread. The key
- // then has its own destructor which runs all the other destructors.
- //
- // The destructor for DTORS is a little special in that it has a `while`
- // loop to continuously drain the list of registered destructors. It
- // *should* be the case that this loop always terminates because we
- // provide the guarantee that a TLS key cannot be set after it is
- // flagged for destruction.
- use sys_common::thread_local as os;
-
- static DTORS: os::StaticKey = os::StaticKey::new(Some(run_dtors));
- type List = Vec<(*mut u8, unsafe extern fn(*mut u8))>;
- if DTORS.get().is_null() {
- let v: Box<List> = box Vec::new();
- DTORS.set(Box::into_raw(v) as *mut u8);
- }
- let list: &mut List = &mut *(DTORS.get() as *mut List);
- list.push((t, dtor));
-
- unsafe extern fn run_dtors(mut ptr: *mut u8) {
- while !ptr.is_null() {
- let list: Box<List> = Box::from_raw(ptr as *mut List);
- for (ptr, dtor) in list.into_iter() {
- dtor(ptr);
- }
- ptr = DTORS.get();
- DTORS.set(ptr::null_mut());
- }
- }
-}
-
-pub unsafe extern fn destroy_value<T>(ptr: *mut u8) {
- let ptr = ptr as *mut Key<T>;
- // Right before we run the user destructor be sure to flag the
- // destructor as running for this thread so calls to `get` will return
- // `None`.
- (*ptr).dtor_running.set(true);
-
- // The macOS implementation of TLS apparently had an odd aspect to it
- // where the pointer we have may be overwritten while this destructor
- // is running. Specifically if a TLS destructor re-accesses TLS it may
- // trigger a re-initialization of all TLS variables, paving over at
- // least some destroyed ones with initial values.
- //
- // This means that if we drop a TLS value in place on macOS that we could
- // revert the value to its original state halfway through the
- // destructor, which would be bad!
- //
- // Hence, we use `ptr::read` on macOS (to move to a "safe" location)
- // instead of drop_in_place.
- if cfg!(target_os = "macos") {
- ptr::read((*ptr).inner.get());
- } else {
- ptr::drop_in_place((*ptr).inner.get());
- }
-}
-
-pub fn requires_move_before_drop() -> bool {
- false
-}