# lib.rs - source
Source of the Rust file `/home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/vcell-0.1.3/src/lib.rs`.
Keywords: rust, rustlang, rust-lang

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    //! Just like [`Cell`] but with [volatile] read / write operations
    //!
    //! [`Cell`]: https://doc.rust-lang.org/std/cell/struct.Cell.html
    //! [volatile]: https://doc.rust-lang.org/std/ptr/fn.read_volatile.html

    #![deny(missing_docs)]
    #![deny(warnings)]
    #![no_std]

    use core::cell::UnsafeCell;
    use core::ptr;

    /// Just like [`Cell`] but with [volatile] read / write operations
    ///
    /// [`Cell`]: https://doc.rust-lang.org/std/cell/struct.Cell.html
    /// [volatile]: https://doc.rust-lang.org/std/ptr/fn.read_volatile.html
    #[repr(transparent)]
    pub struct VolatileCell<T> {
        value: UnsafeCell<T>,
    }

    impl<T> VolatileCell<T> {
        /// Creates a new `VolatileCell` containing the given value
        pub const fn new(value: T) -> Self {
            VolatileCell { value: UnsafeCell::new(value) }
        }

        /// Returns a copy of the contained value
        #[inline(always)]
        pub fn get(&self) -> T
            where T: Copy
        {
            unsafe { ptr::read_volatile(self.value.get()) }
        }

        /// Sets the contained value
        #[inline(always)]
        pub fn set(&self, value: T)
            where T: Copy
        {
            unsafe { ptr::write_volatile(self.value.get(), value) }
        }

        /// Returns a raw pointer to the underlying data in the cell
        #[inline(always)]
        pub fn as_ptr(&self) -> *mut T {
            self.value.get()
        }
    }

    // NOTE implicit because of `UnsafeCell`
    // unsafe impl<T> !Sync for VolatileCell<T> {}