71 lines
1.7 KiB
Rust
71 lines
1.7 KiB
Rust
// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![allow(dead_code)] // not used on all platforms
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use collections::BTreeMap;
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use ptr;
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use sync::atomic::{AtomicUsize, ATOMIC_USIZE_INIT, Ordering};
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pub type Key = usize;
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type Dtor = unsafe extern fn(*mut u8);
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static NEXT_KEY: AtomicUsize = ATOMIC_USIZE_INIT;
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static mut KEYS: *mut BTreeMap<Key, Option<Dtor>> = ptr::null_mut();
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#[thread_local]
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static mut LOCALS: *mut BTreeMap<Key, *mut u8> = ptr::null_mut();
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unsafe fn keys() -> &'static mut BTreeMap<Key, Option<Dtor>> {
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if KEYS == ptr::null_mut() {
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KEYS = Box::into_raw(Box::new(BTreeMap::new()));
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}
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&mut *KEYS
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}
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unsafe fn locals() -> &'static mut BTreeMap<Key, *mut u8> {
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if LOCALS == ptr::null_mut() {
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LOCALS = Box::into_raw(Box::new(BTreeMap::new()));
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}
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&mut *LOCALS
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}
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#[inline]
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pub unsafe fn create(dtor: Option<Dtor>) -> Key {
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let key = NEXT_KEY.fetch_add(1, Ordering::SeqCst);
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keys().insert(key, dtor);
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key
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}
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#[inline]
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pub unsafe fn get(key: Key) -> *mut u8 {
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if let Some(&entry) = locals().get(&key) {
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entry
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} else {
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ptr::null_mut()
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}
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}
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#[inline]
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pub unsafe fn set(key: Key, value: *mut u8) {
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locals().insert(key, value);
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}
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#[inline]
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pub unsafe fn destroy(key: Key) {
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keys().remove(&key);
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}
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#[inline]
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pub fn requires_synchronized_create() -> bool {
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false
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}
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