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//
// DO NOT EDIT. THIS FILE IS GENERATED FROM $SRCDIR/xpcom/io/nsISeekableStream.idl
//
/// `interface nsISeekableStream : nsITellableStream`
///
// 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 nsISeekableStream {
vtable: &'static nsISeekableStreamVTable,
/// 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 nsISeekableStream.
unsafe impl XpCom for nsISeekableStream {
const IID: nsIID = nsID(0x8429d350, 0x1040, 0x4661,
[0x8b, 0x71, 0xf2, 0xa6, 0xba, 0x45, 0x59, 0x80]);
}
// 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 nsISeekableStream {
#[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 nsISeekableStream.
// 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 nsISeekableStreamCoerce {
/// Cheaply cast a value of this type from a `nsISeekableStream`.
fn coerce_from(v: &nsISeekableStream) -> &Self;
}
// The trivial implementation: We can obviously coerce ourselves to ourselves.
impl nsISeekableStreamCoerce for nsISeekableStream {
#[inline]
fn coerce_from(v: &nsISeekableStream) -> &Self {
v
}
}
impl nsISeekableStream {
/// Cast this `nsISeekableStream` to one of its base interfaces.
#[inline]
pub fn coerce<T: nsISeekableStreamCoerce>(&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 nsISeekableStream {
type Target = nsITellableStream;
#[inline]
fn deref(&self) -> &nsITellableStream {
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: nsITellableStreamCoerce> nsISeekableStreamCoerce for T {
#[inline]
fn coerce_from(v: &nsISeekableStream) -> &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 nsISeekableStream
// 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 nsISeekableStreamVTable {
/// We need to include the members from the base interface's vtable at the start
/// of the VTable definition.
pub __base: nsITellableStreamVTable,
/* void seek (in long whence, in long long offset); */
pub Seek: unsafe extern "system" fn (this: *const nsISeekableStream, whence: i32, offset: i64) -> ::nserror::nsresult,
/* void setEOF (); */
pub SetEOF: unsafe extern "system" fn (this: *const nsISeekableStream) -> ::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 nsISeekableStream {
pub const NS_SEEK_SET: i32 = 0;
pub const NS_SEEK_CUR: i32 = 1;
pub const NS_SEEK_END: i32 = 2;
/// ```text
/// /**
/// * seek
/// *
/// * This method moves the stream offset of the steam implementing this
/// * interface.
/// *
/// * @param whence specifies how to interpret the 'offset' parameter in
/// * setting the stream offset associated with the implementing
/// * stream.
/// *
/// * @param offset specifies a value, in bytes, that is used in conjunction
/// * with the 'whence' parameter to set the stream offset of the
/// * implementing stream. A negative value causes seeking in
/// * the reverse direction.
/// *
/// * @throws NS_BASE_STREAM_CLOSED if called on a closed stream.
/// */
/// ```
///
/// `void seek (in long whence, in long long offset);`
#[inline]
pub unsafe fn Seek(&self, whence: i32, offset: i64) -> ::nserror::nsresult {
((*self.vtable).Seek)(self, whence, offset)
}
/// ```text
/// /**
/// * setEOF
/// *
/// * This method truncates the stream at the current offset.
/// *
/// * @throws NS_BASE_STREAM_CLOSED if called on a closed stream.
/// */
/// ```
///
/// `void setEOF ();`
#[inline]
pub unsafe fn SetEOF(&self, ) -> ::nserror::nsresult {
((*self.vtable).SetEOF)(self, )
}
}