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#[cfg(not(feature = "loom"))]
mod loom;
#[cfg(feature = "loom")]
use loom;
mod thread;
mod page;
use std::ptr::NonNull;
use page::Storage;
pub use page::DEFAULT_PAGE_CAP;
pub struct ThreadLocal<T: Send + 'static> {
pool: Storage<T>
}
impl<T: Send + 'static> ThreadLocal<T> {
pub fn new() -> ThreadLocal<T> {
ThreadLocal {
pool: Storage::new()
}
}
#[inline]
pub fn get(&self) -> Option<&T> {
unsafe {
self.pool.get(thread::get())
}
}
#[inline]
pub fn get_or<F: FnOnce() -> T>(&self, f: F) -> &T {
use std::convert::Infallible;
match self.get_or_try::<_, Infallible>(|| Ok(f())) {
Ok(val) => val,
Err(never) => match never {}
}
}
#[inline]
pub fn get_or_try<F, E>(&self, f: F) -> Result<&T, E>
where
F: FnOnce() -> Result<T, E>
{
let id = thread::get();
let obj = unsafe { self.pool.get_or_new(id) };
let val = match obj {
Some(val) => val,
None => {
let ptr = NonNull::from(&*obj);
let val = obj.get_or_insert(f()?);
ThreadLocal::or_try(&self.pool, id, ptr);
val
}
};
Ok(val)
}
#[cold]
fn or_try(pool: &Storage<T>, id: usize, ptr: NonNull<Option<T>>) {
let thread_handle = unsafe {
thread::push(pool.as_threads_ref(), ptr)
};
pool.insert_thread_handle(id, thread_handle);
}
}
impl<T: Send + 'static> Default for ThreadLocal<T> {
#[inline]
fn default() -> ThreadLocal<T> {
ThreadLocal::new()
}
}
unsafe impl<T: Send> Send for ThreadLocal<T> {}
unsafe impl<T: Send> Sync for ThreadLocal<T> {}