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//
// DO NOT EDIT. THIS FILE IS GENERATED FROM $SRCDIR/xpcom/io/nsISafeOutputStream.idl
//
/// `interface nsISafeOutputStream : nsISupports`
///
/// ```text
/// /**
/// * This interface provides a mechanism to control an output stream
/// * that takes care not to overwrite an existing target until it is known
/// * that all writes to the destination succeeded.
/// *
/// * An object that supports this interface is intended to also support
/// * nsIOutputStream.
/// *
/// * For example, a file output stream that supports this interface writes to
/// * a temporary file, and moves it over the original file when |finish| is
/// * called only if the stream can be successfully closed and all writes
/// * succeeded. If |finish| is called but something went wrong during
/// * writing, it will delete the temporary file and not touch the original.
/// * If the stream is closed by calling |close| directly, or the stream
/// * goes away, the original file will not be overwritten, and the temporary
/// * file will be deleted.
/// *
/// * Currently, this interface is implemented only for file output streams.
/// */
/// ```
///
// The actual type definition for the interface. This struct has methods
// declared on it which will call through its vtable. You never want to pass
// this type around by value, always pass it behind a reference.
#[repr(C)]
pub struct nsISafeOutputStream {
vtable: &'static nsISafeOutputStreamVTable,
/// This field is a phantomdata to ensure that the VTable type and any
/// struct containing it is not safe to send across threads by default, as
/// XPCOM is generally not threadsafe.
///
/// If this type is marked as [rust_sync], there will be explicit `Send` and
/// `Sync` implementations on this type, which will override the inherited
/// negative impls from `Rc`.
__nosync: ::std::marker::PhantomData<::std::rc::Rc<u8>>,
// Make the rust compiler aware that there might be interior mutability
// in what actually implements the interface. This works around UB
// introduced by https://github.com/llvm/llvm-project/commit/01859da84bad95fd51d6a03b08b60c660e642a4f
// that a rust lint would make blatantly obvious, but doesn't exist.
// This prevents optimizations, but those optimizations weren't available
// before rustc switched to LLVM 16, and they now cause problems because
// of the UB.
// Until there's a lint available to find all our UB, it's simpler to
// avoid the UB in the first place, at the cost of preventing optimizations
// in places that don't cause UB. But again, those optimizations weren't
// available before.
__maybe_interior_mutability: ::std::cell::UnsafeCell<[u8; 0]>,
}
// Implementing XpCom for an interface exposes its IID, which allows for easy
// use of the `.query_interface<T>` helper method. This also defines that
// method for nsISafeOutputStream.
unsafe impl XpCom for nsISafeOutputStream {
const IID: nsIID = nsID(0x5f914307, 0x5c34, 0x4e1f,
[0x8e, 0x32, 0xec, 0x74, 0x9d, 0x25, 0xb2, 0x7a]);
}
// We need to implement the RefCounted trait so we can be used with `RefPtr`.
// This trait teaches `RefPtr` how to manage our memory.
unsafe impl RefCounted for nsISafeOutputStream {
#[inline]
unsafe fn addref(&self) {
self.AddRef();
}
#[inline]
unsafe fn release(&self) {
self.Release();
}
}
// This trait is implemented on all types which can be coerced to from nsISafeOutputStream.
// It is used in the implementation of `fn coerce<T>`. We hide it from the
// documentation, because it clutters it up a lot.
#[doc(hidden)]
pub trait nsISafeOutputStreamCoerce {
/// Cheaply cast a value of this type from a `nsISafeOutputStream`.
fn coerce_from(v: &nsISafeOutputStream) -> &Self;
}
// The trivial implementation: We can obviously coerce ourselves to ourselves.
impl nsISafeOutputStreamCoerce for nsISafeOutputStream {
#[inline]
fn coerce_from(v: &nsISafeOutputStream) -> &Self {
v
}
}
impl nsISafeOutputStream {
/// Cast this `nsISafeOutputStream` to one of its base interfaces.
#[inline]
pub fn coerce<T: nsISafeOutputStreamCoerce>(&self) -> &T {
T::coerce_from(self)
}
}
// Every interface struct type implements `Deref` to its base interface. This
// causes methods on the base interfaces to be directly avaliable on the
// object. For example, you can call `.AddRef` or `.QueryInterface` directly
// on any interface which inherits from `nsISupports`.
impl ::std::ops::Deref for nsISafeOutputStream {
type Target = nsISupports;
#[inline]
fn deref(&self) -> &nsISupports {
unsafe {
::std::mem::transmute(self)
}
}
}
// Ensure we can use .coerce() to cast to our base types as well. Any type which
// our base interface can coerce from should be coercable from us as well.
impl<T: nsISupportsCoerce> nsISafeOutputStreamCoerce for T {
#[inline]
fn coerce_from(v: &nsISafeOutputStream) -> &Self {
T::coerce_from(v)
}
}
// This struct represents the interface's VTable. A pointer to a statically
// allocated version of this struct is at the beginning of every nsISafeOutputStream
// object. It contains one pointer field for each method in the interface. In
// the case where we can't generate a binding for a method, we include a void
// pointer.
#[doc(hidden)]
#[repr(C)]
pub struct nsISafeOutputStreamVTable {
/// We need to include the members from the base interface's vtable at the start
/// of the VTable definition.
pub __base: nsISupportsVTable,
/* void finish (); */
pub Finish: unsafe extern "system" fn (this: *const nsISafeOutputStream) -> ::nserror::nsresult,
}
// The implementations of the function wrappers which are exposed to rust code.
// Call these methods rather than manually calling through the VTable struct.
impl nsISafeOutputStream {
/// ```text
/// /**
/// * Call this method to close the stream and cause the original target
/// * to be overwritten. Note: if any call to |write| failed to write out
/// * all of the data given to it, then calling this method will |close| the
/// * stream and return failure. Further, if closing the stream fails, this
/// * method will return failure. The original target will be overwritten only
/// * if all calls to |write| succeeded and the stream was successfully closed.
/// */
/// ```
///
/// `void finish ();`
#[inline]
pub unsafe fn Finish(&self, ) -> ::nserror::nsresult {
((*self.vtable).Finish)(self, )
}
}