Deleted vendor folder

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diff --git a/vendor/crossbeam-epoch/src/guard.rs b/vendor/crossbeam-epoch/src/guard.rs
deleted file mode 100644
index 5fe3380..0000000
--- a/vendor/crossbeam-epoch/src/guard.rs
+++ /dev/null
@@ -1,523 +0,0 @@
-use core::fmt;
-use core::mem;
-
-use crate::atomic::Shared;
-use crate::collector::Collector;
-use crate::deferred::Deferred;
-use crate::internal::Local;
-
-/// A guard that keeps the current thread pinned.
-///
-/// # Pinning
-///
-/// The current thread is pinned by calling [`pin`], which returns a new guard:
-///
-/// ```
-/// use crossbeam_epoch as epoch;
-///
-/// // It is often convenient to prefix a call to `pin` with a `&` in order to create a reference.
-/// // This is not really necessary, but makes passing references to the guard a bit easier.
-/// let guard = &epoch::pin();
-/// ```
-///
-/// When a guard gets dropped, the current thread is automatically unpinned.
-///
-/// # Pointers on the stack
-///
-/// Having a guard allows us to create pointers on the stack to heap-allocated objects.
-/// For example:
-///
-/// ```
-/// use crossbeam_epoch::{self as epoch, Atomic};
-/// use std::sync::atomic::Ordering::SeqCst;
-///
-/// // Create a heap-allocated number.
-/// let a = Atomic::new(777);
-///
-/// // Pin the current thread.
-/// let guard = &epoch::pin();
-///
-/// // Load the heap-allocated object and create pointer `p` on the stack.
-/// let p = a.load(SeqCst, guard);
-///
-/// // Dereference the pointer and print the value:
-/// if let Some(num) = unsafe { p.as_ref() } {
-///     println!("The number is {}.", num);
-/// }
-/// # unsafe { drop(a.into_owned()); } // avoid leak
-/// ```
-///
-/// # Multiple guards
-///
-/// Pinning is reentrant and it is perfectly legal to create multiple guards. In that case, the
-/// thread will actually be pinned only when the first guard is created and unpinned when the last
-/// one is dropped:
-///
-/// ```
-/// use crossbeam_epoch as epoch;
-///
-/// let guard1 = epoch::pin();
-/// let guard2 = epoch::pin();
-/// assert!(epoch::is_pinned());
-/// drop(guard1);
-/// assert!(epoch::is_pinned());
-/// drop(guard2);
-/// assert!(!epoch::is_pinned());
-/// ```
-///
-/// [`pin`]: super::pin
-pub struct Guard {
-    pub(crate) local: *const Local,
-}
-
-impl Guard {
-    /// Stores a function so that it can be executed at some point after all currently pinned
-    /// threads get unpinned.
-    ///
-    /// This method first stores `f` into the thread-local (or handle-local) cache. If this cache
-    /// becomes full, some functions are moved into the global cache. At the same time, some
-    /// functions from both local and global caches may get executed in order to incrementally
-    /// clean up the caches as they fill up.
-    ///
-    /// There is no guarantee when exactly `f` will be executed. The only guarantee is that it
-    /// won't be executed until all currently pinned threads get unpinned. In theory, `f` might
-    /// never run, but the epoch-based garbage collection will make an effort to execute it
-    /// reasonably soon.
-    ///
-    /// If this method is called from an [`unprotected`] guard, the function will simply be
-    /// executed immediately.
-    pub fn defer<F, R>(&self, f: F)
-    where
-        F: FnOnce() -> R,
-        F: Send + 'static,
-    {
-        unsafe {
-            self.defer_unchecked(f);
-        }
-    }
-
-    /// Stores a function so that it can be executed at some point after all currently pinned
-    /// threads get unpinned.
-    ///
-    /// This method first stores `f` into the thread-local (or handle-local) cache. If this cache
-    /// becomes full, some functions are moved into the global cache. At the same time, some
-    /// functions from both local and global caches may get executed in order to incrementally
-    /// clean up the caches as they fill up.
-    ///
-    /// There is no guarantee when exactly `f` will be executed. The only guarantee is that it
-    /// won't be executed until all currently pinned threads get unpinned. In theory, `f` might
-    /// never run, but the epoch-based garbage collection will make an effort to execute it
-    /// reasonably soon.
-    ///
-    /// If this method is called from an [`unprotected`] guard, the function will simply be
-    /// executed immediately.
-    ///
-    /// # Safety
-    ///
-    /// The given function must not hold reference onto the stack. It is highly recommended that
-    /// the passed function is **always** marked with `move` in order to prevent accidental
-    /// borrows.
-    ///
-    /// ```
-    /// use crossbeam_epoch as epoch;
-    ///
-    /// let guard = &epoch::pin();
-    /// let message = "Hello!";
-    /// unsafe {
-    ///     // ALWAYS use `move` when sending a closure into `defer_unchecked`.
-    ///     guard.defer_unchecked(move || {
-    ///         println!("{}", message);
-    ///     });
-    /// }
-    /// ```
-    ///
-    /// Apart from that, keep in mind that another thread may execute `f`, so anything accessed by
-    /// the closure must be `Send`.
-    ///
-    /// We intentionally didn't require `F: Send`, because Rust's type systems usually cannot prove
-    /// `F: Send` for typical use cases. For example, consider the following code snippet, which
-    /// exemplifies the typical use case of deferring the deallocation of a shared reference:
-    ///
-    /// ```ignore
-    /// let shared = Owned::new(7i32).into_shared(guard);
-    /// guard.defer_unchecked(move || shared.into_owned()); // `Shared` is not `Send`!
-    /// ```
-    ///
-    /// While `Shared` is not `Send`, it's safe for another thread to call the deferred function,
-    /// because it's called only after the grace period and `shared` is no longer shared with other
-    /// threads. But we don't expect type systems to prove this.
-    ///
-    /// # Examples
-    ///
-    /// When a heap-allocated object in a data structure becomes unreachable, it has to be
-    /// deallocated. However, the current thread and other threads may be still holding references
-    /// on the stack to that same object. Therefore it cannot be deallocated before those references
-    /// get dropped. This method can defer deallocation until all those threads get unpinned and
-    /// consequently drop all their references on the stack.
-    ///
-    /// ```
-    /// use crossbeam_epoch::{self as epoch, Atomic, Owned};
-    /// use std::sync::atomic::Ordering::SeqCst;
-    ///
-    /// let a = Atomic::new("foo");
-    ///
-    /// // Now suppose that `a` is shared among multiple threads and concurrently
-    /// // accessed and modified...
-    ///
-    /// // Pin the current thread.
-    /// let guard = &epoch::pin();
-    ///
-    /// // Steal the object currently stored in `a` and swap it with another one.
-    /// let p = a.swap(Owned::new("bar").into_shared(guard), SeqCst, guard);
-    ///
-    /// if !p.is_null() {
-    ///     // The object `p` is pointing to is now unreachable.
-    ///     // Defer its deallocation until all currently pinned threads get unpinned.
-    ///     unsafe {
-    ///         // ALWAYS use `move` when sending a closure into `defer_unchecked`.
-    ///         guard.defer_unchecked(move || {
-    ///             println!("{} is now being deallocated.", p.deref());
-    ///             // Now we have unique access to the object pointed to by `p` and can turn it
-    ///             // into an `Owned`. Dropping the `Owned` will deallocate the object.
-    ///             drop(p.into_owned());
-    ///         });
-    ///     }
-    /// }
-    /// # unsafe { drop(a.into_owned()); } // avoid leak
-    /// ```
-    pub unsafe fn defer_unchecked<F, R>(&self, f: F)
-    where
-        F: FnOnce() -> R,
-    {
-        if let Some(local) = self.local.as_ref() {
-            local.defer(Deferred::new(move || drop(f())), self);
-        } else {
-            drop(f());
-        }
-    }
-
-    /// Stores a destructor for an object so that it can be deallocated and dropped at some point
-    /// after all currently pinned threads get unpinned.
-    ///
-    /// This method first stores the destructor into the thread-local (or handle-local) cache. If
-    /// this cache becomes full, some destructors are moved into the global cache. At the same
-    /// time, some destructors from both local and global caches may get executed in order to
-    /// incrementally clean up the caches as they fill up.
-    ///
-    /// There is no guarantee when exactly the destructor will be executed. The only guarantee is
-    /// that it won't be executed until all currently pinned threads get unpinned. In theory, the
-    /// destructor might never run, but the epoch-based garbage collection will make an effort to
-    /// execute it reasonably soon.
-    ///
-    /// If this method is called from an [`unprotected`] guard, the destructor will simply be
-    /// executed immediately.
-    ///
-    /// # Safety
-    ///
-    /// The object must not be reachable by other threads anymore, otherwise it might be still in
-    /// use when the destructor runs.
-    ///
-    /// Apart from that, keep in mind that another thread may execute the destructor, so the object
-    /// must be sendable to other threads.
-    ///
-    /// We intentionally didn't require `T: Send`, because Rust's type systems usually cannot prove
-    /// `T: Send` for typical use cases. For example, consider the following code snippet, which
-    /// exemplifies the typical use case of deferring the deallocation of a shared reference:
-    ///
-    /// ```ignore
-    /// let shared = Owned::new(7i32).into_shared(guard);
-    /// guard.defer_destroy(shared); // `Shared` is not `Send`!
-    /// ```
-    ///
-    /// While `Shared` is not `Send`, it's safe for another thread to call the destructor, because
-    /// it's called only after the grace period and `shared` is no longer shared with other
-    /// threads. But we don't expect type systems to prove this.
-    ///
-    /// # Examples
-    ///
-    /// When a heap-allocated object in a data structure becomes unreachable, it has to be
-    /// deallocated. However, the current thread and other threads may be still holding references
-    /// on the stack to that same object. Therefore it cannot be deallocated before those references
-    /// get dropped. This method can defer deallocation until all those threads get unpinned and
-    /// consequently drop all their references on the stack.
-    ///
-    /// ```
-    /// use crossbeam_epoch::{self as epoch, Atomic, Owned};
-    /// use std::sync::atomic::Ordering::SeqCst;
-    ///
-    /// let a = Atomic::new("foo");
-    ///
-    /// // Now suppose that `a` is shared among multiple threads and concurrently
-    /// // accessed and modified...
-    ///
-    /// // Pin the current thread.
-    /// let guard = &epoch::pin();
-    ///
-    /// // Steal the object currently stored in `a` and swap it with another one.
-    /// let p = a.swap(Owned::new("bar").into_shared(guard), SeqCst, guard);
-    ///
-    /// if !p.is_null() {
-    ///     // The object `p` is pointing to is now unreachable.
-    ///     // Defer its deallocation until all currently pinned threads get unpinned.
-    ///     unsafe {
-    ///         guard.defer_destroy(p);
-    ///     }
-    /// }
-    /// # unsafe { drop(a.into_owned()); } // avoid leak
-    /// ```
-    pub unsafe fn defer_destroy<T>(&self, ptr: Shared<'_, T>) {
-        self.defer_unchecked(move || ptr.into_owned());
-    }
-
-    /// Clears up the thread-local cache of deferred functions by executing them or moving into the
-    /// global cache.
-    ///
-    /// Call this method after deferring execution of a function if you want to get it executed as
-    /// soon as possible. Flushing will make sure it is residing in in the global cache, so that
-    /// any thread has a chance of taking the function and executing it.
-    ///
-    /// If this method is called from an [`unprotected`] guard, it is a no-op (nothing happens).
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use crossbeam_epoch as epoch;
-    ///
-    /// let guard = &epoch::pin();
-    /// guard.defer(move || {
-    ///     println!("This better be printed as soon as possible!");
-    /// });
-    /// guard.flush();
-    /// ```
-    pub fn flush(&self) {
-        if let Some(local) = unsafe { self.local.as_ref() } {
-            local.flush(self);
-        }
-    }
-
-    /// Unpins and then immediately re-pins the thread.
-    ///
-    /// This method is useful when you don't want delay the advancement of the global epoch by
-    /// holding an old epoch. For safety, you should not maintain any guard-based reference across
-    /// the call (the latter is enforced by `&mut self`). The thread will only be repinned if this
-    /// is the only active guard for the current thread.
-    ///
-    /// If this method is called from an [`unprotected`] guard, then the call will be just no-op.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use crossbeam_epoch::{self as epoch, Atomic};
-    /// use std::sync::atomic::Ordering::SeqCst;
-    ///
-    /// let a = Atomic::new(777);
-    /// let mut guard = epoch::pin();
-    /// {
-    ///     let p = a.load(SeqCst, &guard);
-    ///     assert_eq!(unsafe { p.as_ref() }, Some(&777));
-    /// }
-    /// guard.repin();
-    /// {
-    ///     let p = a.load(SeqCst, &guard);
-    ///     assert_eq!(unsafe { p.as_ref() }, Some(&777));
-    /// }
-    /// # unsafe { drop(a.into_owned()); } // avoid leak
-    /// ```
-    pub fn repin(&mut self) {
-        if let Some(local) = unsafe { self.local.as_ref() } {
-            local.repin();
-        }
-    }
-
-    /// Temporarily unpins the thread, executes the given function and then re-pins the thread.
-    ///
-    /// This method is useful when you need to perform a long-running operation (e.g. sleeping)
-    /// and don't need to maintain any guard-based reference across the call (the latter is enforced
-    /// by `&mut self`). The thread will only be unpinned if this is the only active guard for the
-    /// current thread.
-    ///
-    /// If this method is called from an [`unprotected`] guard, then the passed function is called
-    /// directly without unpinning the thread.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use crossbeam_epoch::{self as epoch, Atomic};
-    /// use std::sync::atomic::Ordering::SeqCst;
-    /// use std::thread;
-    /// use std::time::Duration;
-    ///
-    /// let a = Atomic::new(777);
-    /// let mut guard = epoch::pin();
-    /// {
-    ///     let p = a.load(SeqCst, &guard);
-    ///     assert_eq!(unsafe { p.as_ref() }, Some(&777));
-    /// }
-    /// guard.repin_after(|| thread::sleep(Duration::from_millis(50)));
-    /// {
-    ///     let p = a.load(SeqCst, &guard);
-    ///     assert_eq!(unsafe { p.as_ref() }, Some(&777));
-    /// }
-    /// # unsafe { drop(a.into_owned()); } // avoid leak
-    /// ```
-    pub fn repin_after<F, R>(&mut self, f: F) -> R
-    where
-        F: FnOnce() -> R,
-    {
-        // Ensure the Guard is re-pinned even if the function panics
-        struct ScopeGuard(*const Local);
-        impl Drop for ScopeGuard {
-            fn drop(&mut self) {
-                if let Some(local) = unsafe { self.0.as_ref() } {
-                    mem::forget(local.pin());
-                    local.release_handle();
-                }
-            }
-        }
-
-        if let Some(local) = unsafe { self.local.as_ref() } {
-            // We need to acquire a handle here to ensure the Local doesn't
-            // disappear from under us.
-            local.acquire_handle();
-            local.unpin();
-        }
-
-        let _guard = ScopeGuard(self.local);
-
-        f()
-    }
-
-    /// Returns the `Collector` associated with this guard.
-    ///
-    /// This method is useful when you need to ensure that all guards used with
-    /// a data structure come from the same collector.
-    ///
-    /// If this method is called from an [`unprotected`] guard, then `None` is returned.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use crossbeam_epoch as epoch;
-    ///
-    /// let guard1 = epoch::pin();
-    /// let guard2 = epoch::pin();
-    /// assert!(guard1.collector() == guard2.collector());
-    /// ```
-    pub fn collector(&self) -> Option<&Collector> {
-        unsafe { self.local.as_ref().map(|local| local.collector()) }
-    }
-}
-
-impl Drop for Guard {
-    #[inline]
-    fn drop(&mut self) {
-        if let Some(local) = unsafe { self.local.as_ref() } {
-            local.unpin();
-        }
-    }
-}
-
-impl fmt::Debug for Guard {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.pad("Guard { .. }")
-    }
-}
-
-/// Returns a reference to a dummy guard that allows unprotected access to [`Atomic`]s.
-///
-/// This guard should be used in special occasions only. Note that it doesn't actually keep any
-/// thread pinned - it's just a fake guard that allows loading from [`Atomic`]s unsafely.
-///
-/// Note that calling [`defer`] with a dummy guard will not defer the function - it will just
-/// execute the function immediately.
-///
-/// If necessary, it's possible to create more dummy guards by cloning: `unprotected().clone()`.
-///
-/// # Safety
-///
-/// Loading and dereferencing data from an [`Atomic`] using this guard is safe only if the
-/// [`Atomic`] is not being concurrently modified by other threads.
-///
-/// # Examples
-///
-/// ```
-/// use crossbeam_epoch::{self as epoch, Atomic};
-/// use std::sync::atomic::Ordering::Relaxed;
-///
-/// let a = Atomic::new(7);
-///
-/// unsafe {
-///     // Load `a` without pinning the current thread.
-///     a.load(Relaxed, epoch::unprotected());
-///
-///     // It's possible to create more dummy guards.
-///     let dummy = epoch::unprotected();
-///
-///     dummy.defer(move || {
-///         println!("This gets executed immediately.");
-///     });
-///
-///     // Dropping `dummy` doesn't affect the current thread - it's just a noop.
-/// }
-/// # unsafe { drop(a.into_owned()); } // avoid leak
-/// ```
-///
-/// The most common use of this function is when constructing or destructing a data structure.
-///
-/// For example, we can use a dummy guard in the destructor of a Treiber stack because at that
-/// point no other thread could concurrently modify the [`Atomic`]s we are accessing.
-///
-/// If we were to actually pin the current thread during destruction, that would just unnecessarily
-/// delay garbage collection and incur some performance cost, so in cases like these `unprotected`
-/// is very helpful.
-///
-/// ```
-/// use crossbeam_epoch::{self as epoch, Atomic};
-/// use std::mem::ManuallyDrop;
-/// use std::sync::atomic::Ordering::Relaxed;
-///
-/// struct Stack<T> {
-///     head: Atomic<Node<T>>,
-/// }
-///
-/// struct Node<T> {
-///     data: ManuallyDrop<T>,
-///     next: Atomic<Node<T>>,
-/// }
-///
-/// impl<T> Drop for Stack<T> {
-///     fn drop(&mut self) {
-///         unsafe {
-///             // Unprotected load.
-///             let mut node = self.head.load(Relaxed, epoch::unprotected());
-///
-///             while let Some(n) = node.as_ref() {
-///                 // Unprotected load.
-///                 let next = n.next.load(Relaxed, epoch::unprotected());
-///
-///                 // Take ownership of the node, then drop its data and deallocate it.
-///                 let mut o = node.into_owned();
-///                 ManuallyDrop::drop(&mut o.data);
-///                 drop(o);
-///
-///                 node = next;
-///             }
-///         }
-///     }
-/// }
-/// ```
-///
-/// [`Atomic`]: super::Atomic
-/// [`defer`]: Guard::defer
-#[inline]
-pub unsafe fn unprotected() -> &'static Guard {
-    // An unprotected guard is just a `Guard` with its field `local` set to null.
-    // We make a newtype over `Guard` because `Guard` isn't `Sync`, so can't be directly stored in
-    // a `static`
-    struct GuardWrapper(Guard);
-    unsafe impl Sync for GuardWrapper {}
-    static UNPROTECTED: GuardWrapper = GuardWrapper(Guard {
-        local: core::ptr::null(),
-    });
-    &UNPROTECTED.0
-}