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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /third_party/rust/comedy/src/com.rs
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/comedy/src/com.rs')
-rw-r--r--third_party/rust/comedy/src/com.rs478
1 files changed, 478 insertions, 0 deletions
diff --git a/third_party/rust/comedy/src/com.rs b/third_party/rust/comedy/src/com.rs
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+// Licensed under the Apache License, Version 2.0
+// <LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// All files in the project carrying such notice may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Utilities and wrappers for Microsoft COM interfaces in Windows.
+//!
+//! This works with the `Class` and `Interface` traits from the `winapi` crate.
+
+use std::marker::PhantomData;
+use std::mem;
+use std::ops::Deref;
+use std::ptr::{self, null_mut, NonNull};
+use std::rc::Rc;
+use std::slice;
+
+use winapi::shared::minwindef::LPVOID;
+use winapi::shared::{
+ winerror::HRESULT,
+ wtypesbase::{CLSCTX, CLSCTX_INPROC_SERVER, CLSCTX_LOCAL_SERVER},
+};
+use winapi::um::{
+ combaseapi::{CoCreateInstance, CoInitializeEx, CoTaskMemFree, CoUninitialize},
+ objbase::{COINIT_APARTMENTTHREADED, COINIT_MULTITHREADED},
+ unknwnbase::IUnknown,
+};
+use winapi::{Class, Interface};
+
+use check_succeeded;
+use error::{succeeded_or_err, HResult, ResultExt};
+
+/// Wrap COM interfaces sanely
+///
+/// Originally from [wio-rs](https://github.com/retep998/wio-rs) `ComPtr`
+#[repr(transparent)]
+pub struct ComRef<T>(NonNull<T>)
+where
+ T: Interface;
+impl<T> ComRef<T>
+where
+ T: Interface,
+{
+ /// Creates a `ComRef` to wrap a raw pointer.
+ /// It takes ownership over the pointer which means it does __not__ call `AddRef`.
+ /// `T` __must__ be a COM interface that inherits from `IUnknown`.
+ pub unsafe fn from_raw(ptr: NonNull<T>) -> ComRef<T> {
+ ComRef(ptr)
+ }
+
+ /// Casts up the inheritance chain
+ pub fn up<U>(self) -> ComRef<U>
+ where
+ T: Deref<Target = U>,
+ U: Interface,
+ {
+ unsafe { ComRef::from_raw(NonNull::new(self.into_raw().as_ptr() as *mut U).unwrap()) }
+ }
+
+ /// Extracts the raw pointer.
+ /// You are now responsible for releasing it yourself.
+ pub fn into_raw(self) -> NonNull<T> {
+ let p = self.0;
+ mem::forget(self);
+ p
+ }
+
+ fn as_unknown(&self) -> &IUnknown {
+ unsafe { &*(self.as_raw_ptr() as *mut IUnknown) }
+ }
+
+ /// Get another interface via `QueryInterface`.
+ ///
+ /// If the call to `QueryInterface` fails or the resulting interface is null, return an error.
+ pub fn cast<U>(&self) -> Result<ComRef<U>, HResult>
+ where
+ U: Interface,
+ {
+ let mut obj = null_mut();
+ let hr =
+ succeeded_or_err(unsafe { self.as_unknown().QueryInterface(&U::uuidof(), &mut obj) })?;
+ NonNull::new(obj as *mut U)
+ .map(|obj| unsafe { ComRef::from_raw(obj) })
+ .ok_or_else(|| HResult::new(hr).function("IUnknown::QueryInterface"))
+ }
+
+ /// Obtains the raw pointer without transferring ownership.
+ ///
+ /// Do __not__ release this pointer because it is still owned by the `ComRef`.
+ ///
+ /// Do __not__ use this pointer beyond the lifetime of the `ComRef`.
+ pub fn as_raw(&self) -> NonNull<T> {
+ self.0
+ }
+
+ /// Obtains the raw pointer without transferring ownership.
+ ///
+ /// Do __not__ release this pointer because it is still owned by the `ComRef`.
+ ///
+ /// Do __not__ use this pointer beyond the lifetime of the `ComRef`.
+ pub fn as_raw_ptr(&self) -> *mut T {
+ self.0.as_ptr()
+ }
+}
+impl<T> Deref for ComRef<T>
+where
+ T: Interface,
+{
+ type Target = T;
+ fn deref(&self) -> &T {
+ unsafe { &*self.as_raw_ptr() }
+ }
+}
+impl<T> Clone for ComRef<T>
+where
+ T: Interface,
+{
+ fn clone(&self) -> Self {
+ unsafe {
+ self.as_unknown().AddRef();
+ ComRef::from_raw(self.as_raw())
+ }
+ }
+}
+impl<T> Drop for ComRef<T>
+where
+ T: Interface,
+{
+ fn drop(&mut self) {
+ unsafe {
+ self.as_unknown().Release();
+ }
+ }
+}
+
+/// A scope for automatic COM initialization and deinitialization.
+///
+/// Functions that need COM initialized can take a `&ComApartmentScope` argument and be sure that
+/// it is so. It's recommended to use a thread local for this through the
+/// [`INIT_MTA`](constant.INIT_MTA.html) or [`INIT_STA`](constant.INIT_STA.html) statics.
+#[derive(Debug, Default)]
+pub struct ComApartmentScope {
+ /// PhantomData used in lieu of unstable impl !Send + !Sync.
+ /// It must be dropped on the same thread it was created on so it can't be Send,
+ /// and references are meant to indicate that COM has been inited on the current thread so it
+ /// can't be Sync.
+ _do_not_send: PhantomData<Rc<()>>,
+}
+
+impl ComApartmentScope {
+ /// This thread should be the sole occupant of a single thread apartment
+ pub fn init_sta() -> Result<Self, HResult> {
+ unsafe { check_succeeded!(CoInitializeEx(ptr::null_mut(), COINIT_APARTMENTTHREADED)) }?;
+
+ Ok(Default::default())
+ }
+
+ /// This thread should join the process's multithreaded apartment
+ pub fn init_mta() -> Result<Self, HResult> {
+ unsafe { check_succeeded!(CoInitializeEx(ptr::null_mut(), COINIT_MULTITHREADED)) }?;
+
+ Ok(Default::default())
+ }
+}
+
+impl Drop for ComApartmentScope {
+ fn drop(&mut self) {
+ unsafe {
+ CoUninitialize();
+ }
+ }
+}
+
+thread_local! {
+ // TODO these examples should probably be in convenience functions.
+ /// A single thread apartment scope for the duration of the current thread.
+ ///
+ /// # Example
+ /// ```
+ /// use comedy::com::{ComApartmentScope, INIT_STA};
+ ///
+ /// fn do_com_stuff(_com: &ComApartmentScope) {
+ /// }
+ ///
+ /// INIT_STA.with(|com| {
+ /// let com = match com {
+ /// Err(e) => return Err(e.clone()),
+ /// Ok(ref com) => com,
+ /// };
+ /// do_com_stuff(com);
+ /// Ok(())
+ /// }).unwrap()
+ /// ```
+ pub static INIT_STA: Result<ComApartmentScope, HResult> = ComApartmentScope::init_sta();
+
+ /// A multithreaded apartment scope for the duration of the current thread.
+ ///
+ /// # Example
+ /// ```
+ /// use comedy::com::{ComApartmentScope, INIT_MTA};
+ ///
+ /// fn do_com_stuff(_com: &ComApartmentScope) {
+ /// }
+ ///
+ /// INIT_MTA.with(|com| {
+ /// let com = match com {
+ /// Err(e) => return Err(e.clone()),
+ /// Ok(ref com) => com,
+ /// };
+ /// do_com_stuff(com);
+ /// Ok(())
+ /// }).unwrap()
+ /// ```
+ pub static INIT_MTA: Result<ComApartmentScope, HResult> = ComApartmentScope::init_mta();
+}
+
+/// Create an instance of a COM class.
+///
+/// This is mostly just a call to `CoCreateInstance` with some error handling.
+/// The CLSID of the class and the IID of the interface come from the winapi `RIDL` macro, which
+/// defines `Class` and `Interface` implementations.
+///
+/// [`create_instance_local_server`](fn.create_instance_local_server.html) and
+/// [`create_instance_inproc_server`](fn.create_instance_inproc_server.html) are convenience
+/// functions for typical contexts.
+pub fn create_instance<C, I>(ctx: CLSCTX) -> Result<ComRef<I>, HResult>
+where
+ C: Class,
+ I: Interface,
+{
+ get(|interface| unsafe {
+ CoCreateInstance(
+ &C::uuidof(),
+ ptr::null_mut(), // pUnkOuter
+ ctx,
+ &I::uuidof(),
+ interface as *mut *mut _,
+ )
+ })
+ .function("CoCreateInstance")
+}
+
+/// Create an instance of a COM class in the current process (`CLSCTX_LOCAL_SERVER`).
+pub fn create_instance_local_server<C, I>() -> Result<ComRef<I>, HResult>
+where
+ C: Class,
+ I: Interface,
+{
+ create_instance::<C, I>(CLSCTX_LOCAL_SERVER)
+}
+
+/// Create an instance of a COM class in a separate process space on the same machine
+/// (`CLSCTX_INPROC_SERVER`).
+pub fn create_instance_inproc_server<C, I>() -> Result<ComRef<I>, HResult>
+where
+ C: Class,
+ I: Interface,
+{
+ create_instance::<C, I>(CLSCTX_INPROC_SERVER)
+}
+
+/// Call a COM method, returning a `Result`.
+///
+/// An error is returned if the call fails. The error is augmented with the name of the interface
+/// and method, and the file name and line number of the macro usage.
+///
+/// `QueryInterface` is not used, the receiving interface must already be the given type.
+///
+/// # Example
+///
+/// ```no_run
+/// # extern crate winapi;
+/// #
+/// # use winapi::um::bits::IBackgroundCopyJob;
+/// #
+/// # use comedy::com::ComRef;
+/// # use comedy::{com_call, HResult};
+/// #
+/// fn cancel_job(job: &ComRef<IBackgroundCopyJob>) -> Result<(), HResult> {
+/// unsafe {
+/// com_call!(job, IBackgroundCopyJob::Cancel())?;
+/// }
+/// Ok(())
+/// }
+/// ```
+#[macro_export]
+macro_rules! com_call {
+ ($obj:expr, $interface:ident :: $method:ident ( $($arg:expr),* )) => {{
+ use $crate::error::ResultExt;
+ $crate::error::succeeded_or_err({
+ let obj: &$interface = &*$obj;
+ obj.$method($($arg),*)
+ }).function(concat!(stringify!($interface), "::", stringify!($method)))
+ .file_line(file!(), line!())
+ }};
+
+ // support for trailing comma in method argument list
+ ($obj:expr, $interface:ident :: $method:ident ( $($arg:expr),+ , )) => {{
+ $crate::com_call!($obj, $interface::$method($($arg),+))
+ }};
+}
+
+/// Get an interface pointer that is returned through an output parameter.
+///
+/// If the call returns a failure `HRESULT`, return an error.
+///
+///
+/// # Null and Enumerators
+/// If the method succeeds but the resulting interface pointer is null, this will return an
+/// `HResult` error with the successful return code. In particular this can happen with
+/// enumeration interfaces, which return `S_FALSE` when they write less than the requested number
+/// of results.
+pub fn get<I, F>(getter: F) -> Result<ComRef<I>, HResult>
+where
+ I: Interface,
+ F: FnOnce(*mut *mut I) -> HRESULT,
+{
+ let mut interface: *mut I = ptr::null_mut();
+
+ let hr = succeeded_or_err(getter(&mut interface as *mut *mut I))?;
+
+ NonNull::new(interface)
+ .map(|interface| unsafe { ComRef::from_raw(interface) })
+ .ok_or_else(|| HResult::new(hr))
+}
+
+/// Call a COM method, create a [`ComRef`](com/struct.ComRef.html) from an output parameter.
+///
+/// An error is returned if the call fails. The error is augmented with the name of the interface
+/// and method, and the file name and line number of the macro usage.
+///
+/// # Null and Enumerators
+/// If the method succeeds but the resulting interface pointer is null, this will return an
+/// `HResult` error with the successful return code. In particular this can happen with
+/// enumeration interfaces, which return `S_FALSE` when they write less than the requested number
+/// of results.
+///
+/// # Example
+///
+/// ```no_run
+/// # extern crate winapi;
+/// # use winapi::shared::guiddef::GUID;
+/// # use winapi::um::bits::{IBackgroundCopyManager, IBackgroundCopyJob};
+/// # use comedy::com::ComRef;
+/// # use comedy::{com_call_getter, HResult};
+///
+/// fn create_job(bcm: &ComRef<IBackgroundCopyManager>, id: &GUID)
+/// -> Result<ComRef<IBackgroundCopyJob>, HResult>
+/// {
+/// unsafe {
+/// com_call_getter!(
+/// |job| bcm,
+/// IBackgroundCopyManager::GetJob(id, job)
+/// )
+/// }
+/// }
+/// ```
+#[macro_export]
+macro_rules! com_call_getter {
+ (| $outparam:ident | $obj:expr, $interface:ident :: $method:ident ( $($arg:expr),* )) => {{
+ use $crate::error::ResultExt;
+ let obj: &$interface = &*$obj;
+ $crate::com::get(|$outparam| {
+ obj.$method($($arg),*)
+ }).function(concat!(stringify!($interface), "::", stringify!($method)))
+ .file_line(file!(), line!())
+ }};
+
+ // support for trailing comma in method argument list
+ (| $outparam:ident | $obj:expr, $interface:ident :: $method:ident ( $($arg:expr),+ , )) => {
+ $crate::com_call_getter!(|$outparam| $obj, $interface::$method($($arg),+))
+ };
+}
+
+/// Get a task memory pointer that is returned through an output parameter.
+///
+/// If the call returns a failure `HRESULT`, return an error.
+///
+/// # Null
+/// If the method succeeds but the resulting pointer is null, this will return an
+/// `Err(HResult)` with the successful return code.
+pub fn get_cotaskmem<F, T>(getter: F) -> Result<CoTaskMem<T>, HResult>
+where
+ F: FnOnce(*mut *mut T) -> HRESULT,
+{
+ let mut ptr = ptr::null_mut() as *mut T;
+
+ let hr = succeeded_or_err(getter(&mut ptr))?;
+
+ NonNull::new(ptr)
+ .map(|ptr| unsafe { CoTaskMem::new(ptr) })
+ .ok_or_else(|| HResult::new(hr))
+}
+
+/// Call a COM method, create a [`CoTaskMem`](handle/struct.CoTaskMem.html) from an output
+/// parameter.
+///
+/// An error is returned if the call fails or if the pointer is null. The error is augmented with
+/// the name of the interface and method, and the file name and line number of the macro usage.
+///
+/// # Null
+/// If the method succeeds but the resulting pointer is null, this will return an `HResult`
+/// error with the successful return code.
+///
+/// # Example
+///
+/// ```no_run
+/// # extern crate winapi;
+/// # use winapi::shared::winerror::HRESULT;
+/// # use winapi::um::bits::IBackgroundCopyManager;
+/// # use comedy::com::{ComRef, CoTaskMem};
+/// # use comedy::{com_call_taskmem_getter, HResult};
+/// #
+/// fn get_error_description(bcm: &ComRef<IBackgroundCopyManager>, lang_id: u32, hr: HRESULT)
+/// -> Result<CoTaskMem<u16>, HResult>
+/// {
+/// unsafe {
+/// com_call_taskmem_getter!(
+/// |desc| bcm,
+/// IBackgroundCopyManager::GetErrorDescription(hr, lang_id, desc)
+/// )
+/// }
+/// }
+/// ```
+#[macro_export]
+macro_rules! com_call_taskmem_getter {
+ (| $outparam:ident | $obj:expr, $interface:ident :: $method:ident ( $($arg:expr),* )) => {{
+ use $crate::error::ResultExt;
+ $crate::com::get_cotaskmem(|$outparam| {
+ $obj.$method($($arg),*)
+ }).function(concat!(stringify!($interface), "::", stringify!($method)))
+ .file_line(file!(), line!())
+ }};
+
+ // support for trailing comma in method argument list
+ (| $outparam:ident | $obj:expr, $interface:ident :: $method:ident ( $($arg:expr),+ , )) => {
+ $crate::com_call_taskmem_getter!(|$outparam| $obj, $interface::$method($($arg),+))
+ };
+}
+
+/// A Windows COM task memory pointer that will be automatically freed.
+// I have only found this useful with strings, so that is the only access provided here by
+// `as_slice_until_null()`. `Deref<Target=T>` would not be generally useful as task memory
+// is usually encountered as variable length structures.
+#[repr(transparent)]
+#[derive(Debug)]
+pub struct CoTaskMem<T>(NonNull<T>);
+
+impl<T> CoTaskMem<T> {
+ /// Take ownership of COM task memory, which will be freed with `CoTaskMemFree()` upon drop.
+ ///
+ /// # Safety
+ ///
+ /// `p` should be the only copy of the pointer.
+ pub unsafe fn new(p: NonNull<T>) -> CoTaskMem<T> {
+ CoTaskMem(p)
+ }
+}
+
+impl<T> Drop for CoTaskMem<T> {
+ fn drop(&mut self) {
+ unsafe {
+ CoTaskMemFree(self.0.as_ptr() as LPVOID);
+ }
+ }
+}
+
+impl CoTaskMem<u16> {
+ /// Interpret as a null-terminated `u16` array, return as a slice without terminator.
+ pub unsafe fn as_slice_until_null(&self) -> &[u16] {
+ for i in 0.. {
+ if *self.0.as_ptr().offset(i) == 0 {
+ return slice::from_raw_parts(self.0.as_ptr(), i as usize);
+ }
+ }
+ unreachable!()
+ }
+}