Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 964 insertions, 0 deletions

diff --git a/third_party/rust/comedy/src/com.rs b/third_party/rust/comedy/src/com.rs
new file mode 100644
index 0000000000..bce77576ac
--- /dev/null
+++ b/third_party/rust/comedy/src/com.rs
@@ -0,0 +1,478 @@
+// 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!()
+    }
+}
diff --git a/third_party/rust/comedy/src/error.rs b/third_party/rust/comedy/src/error.rs
new file mode 100644
index 0000000000..fdaae493c1
--- /dev/null
+++ b/third_party/rust/comedy/src/error.rs
@@ -0,0 +1,377 @@
+// 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.
+
+//! Wrap several flavors of Windows error into a `Result`.
+
+use std::error::Error;
+use std::fmt;
+
+use winapi::shared::minwindef::DWORD;
+use winapi::shared::winerror::{
+    ERROR_SUCCESS, FACILITY_WIN32, HRESULT, HRESULT_FROM_WIN32, SUCCEEDED, S_OK,
+};
+use winapi::um::errhandlingapi::GetLastError;
+
+/// An error code, optionally with information about the failing call.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct ErrorAndSource<T: ErrorCode> {
+    code: T,
+    function: Option<&'static str>,
+    file_line: Option<FileLine>,
+}
+
+/// A wrapper for an error code.
+pub trait ErrorCode:
+    Copy + fmt::Debug + Eq + PartialEq + fmt::Display + Send + Sync + 'static
+{
+    type InnerT: Copy + Eq + PartialEq;
+
+    fn get(&self) -> Self::InnerT;
+}
+
+impl<T> ErrorAndSource<T>
+where
+    T: ErrorCode,
+{
+    /// Get the underlying error code.
+    pub fn code(&self) -> T::InnerT {
+        self.code.get()
+    }
+
+    /// Add the name of the failing function to the error.
+    pub fn function(self, function: &'static str) -> Self {
+        Self {
+            function: Some(function),
+            ..self
+        }
+    }
+
+    /// Get the name of the failing function, if known.
+    pub fn get_function(&self) -> Option<&'static str> {
+        self.function
+    }
+
+    /// Add the source file name and line number of the call to the error.
+    pub fn file_line(self, file: &'static str, line: u32) -> Self {
+        Self {
+            file_line: Some(FileLine(file, line)),
+            ..self
+        }
+    }
+
+    /// Get the source file name and line number of the failing call.
+    pub fn get_file_line(&self) -> &Option<FileLine> {
+        &self.file_line
+    }
+}
+
+impl<T> fmt::Display for ErrorAndSource<T>
+where
+    T: ErrorCode,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        if let Some(function) = self.function {
+            if let Some(ref file_line) = self.file_line {
+                write!(f, "{} ", file_line)?;
+            }
+
+            write!(f, "{} ", function)?;
+
+            write!(f, "error: ")?;
+        }
+
+        write!(f, "{}", self.code)?;
+
+        Ok(())
+    }
+}
+
+impl<T> Error for ErrorAndSource<T> where T: ErrorCode {}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct FileLine(pub &'static str, pub u32);
+
+impl fmt::Display for FileLine {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(f, "{}:{}", self.0, self.1)
+    }
+}
+
+/// A [Win32 error code](https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/18d8fbe8-a967-4f1c-ae50-99ca8e491d2d),
+/// usually from `GetLastError()`.
+///
+/// Includes optional function name, source file name, and line number. See
+/// [`ErrorAndSource`](struct.ErrorAndSource.html) for additional methods.
+pub type Win32Error = ErrorAndSource<Win32ErrorInner>;
+
+impl Win32Error {
+    /// Create from an error code.
+    pub fn new(code: DWORD) -> Self {
+        Win32Error {
+            code: Win32ErrorInner(code),
+            function: None,
+            file_line: None,
+        }
+    }
+
+    /// Create from `GetLastError()`
+    pub fn get_last_error() -> Self {
+        Win32Error::new(unsafe { GetLastError() })
+    }
+}
+
+#[doc(hidden)]
+#[repr(transparent)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct Win32ErrorInner(DWORD);
+
+impl ErrorCode for Win32ErrorInner {
+    type InnerT = DWORD;
+
+    fn get(&self) -> DWORD {
+        self.0
+    }
+}
+
+impl fmt::Display for Win32ErrorInner {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(f, "{:#010x}", self.0)
+    }
+}
+
+/// An [HRESULT error code](https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/0642cb2f-2075-4469-918c-4441e69c548a).
+/// These usually come from COM APIs.
+///
+/// Includes optional function name, source file name, and line number. See
+/// [`ErrorAndSource`](struct.ErrorAndSource.html) for additional methods.
+pub type HResult = ErrorAndSource<HResultInner>;
+
+impl HResult {
+    /// Create from an `HRESULT`.
+    pub fn new(hr: HRESULT) -> Self {
+        HResult {
+            code: HResultInner(hr),
+            function: None,
+            file_line: None,
+        }
+    }
+
+    /// Get the result code portion of the `HRESULT`
+    pub fn extract_code(&self) -> HRESULT {
+        // from winerror.h HRESULT_CODE macro
+        self.code.0 & 0xFFFF
+    }
+
+    /// Get the facility portion of the `HRESULT`
+    pub fn extract_facility(&self) -> HRESULT {
+        // from winerror.h HRESULT_FACILITY macro
+        (self.code.0 >> 16) & 0x1fff
+    }
+
+    /// If the `HResult` corresponds to a Win32 error, convert.
+    ///
+    /// Returns the original `HResult` as an error on failure.
+    pub fn try_into_win32_err(self) -> Result<Win32Error, Self> {
+        let code = if self.code() == S_OK {
+            // Special case, facility is not set.
+            ERROR_SUCCESS
+        } else if self.extract_facility() == FACILITY_WIN32 {
+            self.extract_code() as DWORD
+        } else {
+            return Err(self);
+        };
+
+        Ok(Win32Error {
+            code: Win32ErrorInner(code),
+            function: self.function,
+            file_line: self.file_line,
+        })
+    }
+}
+
+#[doc(hidden)]
+#[repr(transparent)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct HResultInner(HRESULT);
+
+impl ErrorCode for HResultInner {
+    type InnerT = HRESULT;
+
+    fn get(&self) -> HRESULT {
+        self.0
+    }
+}
+
+impl fmt::Display for HResultInner {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(f, "HRESULT {:#010x}", self.0)
+    }
+}
+
+/// Extra functions to work with a `Result<T, ErrorAndSource>`.
+pub trait ResultExt<T, E> {
+    type Code;
+
+    /// Add the name of the failing function to the error.
+    fn function(self, function: &'static str) -> Self;
+
+    /// Add the source file name and line number of the call to the error.
+    fn file_line(self, file: &'static str, line: u32) -> Self;
+
+    /// Replace `Err(code)` with `Ok(replacement)`.
+    fn allow_err(self, code: Self::Code, replacement: T) -> Self;
+
+    /// Replace `Err(code)` with `Ok(replacement())`.
+    fn allow_err_with<F>(self, code: Self::Code, replacement: F) -> Self
+    where
+        F: FnOnce() -> T;
+}
+
+impl<T, EC> ResultExt<T, ErrorAndSource<EC>> for Result<T, ErrorAndSource<EC>>
+where
+    EC: ErrorCode,
+{
+    type Code = EC::InnerT;
+
+    fn function(self, function: &'static str) -> Self {
+        self.map_err(|e| e.function(function))
+    }
+
+    fn file_line(self, file: &'static str, line: u32) -> Self {
+        self.map_err(|e| e.file_line(file, line))
+    }
+
+    fn allow_err(self, code: Self::Code, replacement: T) -> Self {
+        self.or_else(|e| {
+            if e.code() == code {
+                Ok(replacement)
+            } else {
+                Err(e)
+            }
+        })
+    }
+
+    fn allow_err_with<F>(self, code: Self::Code, replacement: F) -> Self
+    where
+        F: FnOnce() -> T,
+    {
+        self.or_else(|e| {
+            if e.code() == code {
+                Ok(replacement())
+            } else {
+                Err(e)
+            }
+        })
+    }
+}
+
+impl From<Win32Error> for HResult {
+    fn from(win32_error: Win32Error) -> Self {
+        HResult {
+            code: HResultInner(HRESULT_FROM_WIN32(win32_error.code())),
+            function: win32_error.function,
+            file_line: win32_error.file_line,
+        }
+    }
+}
+
+/// Convert an `HRESULT` into a `Result`.
+pub fn succeeded_or_err(hr: HRESULT) -> Result<HRESULT, HResult> {
+    if !SUCCEEDED(hr) {
+        Err(HResult::new(hr))
+    } else {
+        Ok(hr)
+    }
+}
+
+/// Call a function that returns an `HRESULT`, convert to a `Result`.
+///
+/// The error will be augmented with the name of the function and the file and line number of
+/// the macro usage.
+///
+/// # Example
+/// ```no_run
+/// # extern crate winapi;
+/// # use std::ptr;
+/// # use winapi::um::combaseapi::CoUninitialize;
+/// # use winapi::um::objbase::CoInitialize;
+/// # use comedy::{check_succeeded, HResult};
+/// #
+/// fn coinit() -> Result<(), HResult> {
+///     unsafe {
+///         check_succeeded!(CoInitialize(ptr::null_mut()))?;
+///
+///         CoUninitialize();
+///     }
+///     Ok(())
+/// }
+/// ```
+#[macro_export]
+macro_rules! check_succeeded {
+    ($f:ident ( $($arg:expr),* )) => {
+        {
+            use $crate::error::ResultExt;
+            $crate::error::succeeded_or_err($f($($arg),*))
+                .function(stringify!($f))
+                .file_line(file!(), line!())
+        }
+    };
+
+    // support for trailing comma in argument list
+    ($f:ident ( $($arg:expr),+ , )) => {
+        $crate::check_succeeded!($f($($arg),+))
+    };
+}
+
+/// Convert an integer return value into a `Result`, using `GetLastError()` if zero.
+pub fn true_or_last_err<T>(rv: T) -> Result<T, Win32Error>
+where
+    T: Eq,
+    T: From<bool>,
+{
+    if rv == T::from(false) {
+        Err(Win32Error::get_last_error())
+    } else {
+        Ok(rv)
+    }
+}
+
+/// Call a function that returns a integer, convert to a `Result`, using `GetLastError()` if zero.
+///
+/// The error will be augmented with the name of the function and the file and line number of
+/// the macro usage.
+///
+/// # Example
+/// ```no_run
+/// # extern crate winapi;
+/// # use winapi::shared::minwindef::BOOL;
+/// # use winapi::um::fileapi::FlushFileBuffers;
+/// # use winapi::um::winnt::HANDLE;
+/// # use comedy::{check_true, Win32Error};
+/// #
+/// fn flush(file: HANDLE) -> Result<(), Win32Error> {
+///     unsafe {
+///         check_true!(FlushFileBuffers(file))?;
+///     }
+///     Ok(())
+/// }
+/// ```
+#[macro_export]
+macro_rules! check_true {
+    ($f:ident ( $($arg:expr),* )) => {
+        {
+            use $crate::error::ResultExt;
+            $crate::error::true_or_last_err($f($($arg),*))
+                .function(stringify!($f))
+                .file_line(file!(), line!())
+        }
+    };
+
+    // support for trailing comma in argument list
+    ($f:ident ( $($arg:expr),+ , )) => {
+        $crate::check_true!($f($($arg),+))
+    };
+}
diff --git a/third_party/rust/comedy/src/handle.rs b/third_party/rust/comedy/src/handle.rs
new file mode 100644
index 0000000000..e31d53773e
--- /dev/null
+++ b/third_party/rust/comedy/src/handle.rs
@@ -0,0 +1,91 @@
+// 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.
+
+//! Wrapping and automatically closing handles.
+
+use winapi::shared::minwindef::DWORD;
+use winapi::shared::ntdef::NULL;
+use winapi::um::errhandlingapi::GetLastError;
+use winapi::um::handleapi::{CloseHandle, INVALID_HANDLE_VALUE};
+use winapi::um::winnt::HANDLE;
+
+/// Check and automatically close a Windows `HANDLE`.
+#[repr(transparent)]
+#[derive(Debug)]
+pub struct Handle(HANDLE);
+
+impl Handle {
+    /// Take ownership of a `HANDLE`, which will be closed with `CloseHandle` upon drop.
+    /// Returns an error in case of `INVALID_HANDLE_VALUE` or `NULL`.
+    ///
+    /// # Safety
+    ///
+    /// `h` should be the only copy of the handle. `GetLastError()` is called to
+    /// return an error, so the last Windows API called on this thread should have been
+    /// what produced the invalid handle.
+    pub unsafe fn new(h: HANDLE) -> Result<Handle, DWORD> {
+        if h == NULL || h == INVALID_HANDLE_VALUE {
+            Err(GetLastError())
+        } else {
+            Ok(Handle(h))
+        }
+    }
+
+    /// Obtains the raw `HANDLE` without transferring ownership.
+    ///
+    /// Do __not__ close this handle because it is still owned by the `Handle`.
+    ///
+    /// Do __not__ use this handle beyond the lifetime of the `Handle`.
+    pub fn as_raw(&self) -> HANDLE {
+        self.0
+    }
+}
+
+impl Drop for Handle {
+    fn drop(&mut self) {
+        unsafe {
+            CloseHandle(self.0);
+        }
+    }
+}
+
+/// Call a function that returns a `HANDLE` (`NULL` or `INVALID_HANDLE_VALUE` on failure), wrap result.
+///
+/// The handle is wrapped in a [`Handle`](handle/struct.Handle.html) which will automatically call
+/// `CloseHandle()` on it. If the function fails, the error is retrieved via `GetLastError()` and
+/// augmented with the name of the function and the file and line number of the macro usage.
+///
+/// # Example
+///
+/// ```no_run
+/// # extern crate winapi;
+/// # use std::ptr;
+/// # use winapi::um::fileapi::FindFirstFileW;
+/// # use winapi::um::minwinbase::WIN32_FIND_DATAW;
+/// # use comedy::handle::Handle;
+/// # use comedy::{call_handle_getter, Win32Error};
+/// #
+/// unsafe fn find_first(name: &[u16], data: &mut WIN32_FIND_DATAW) -> Result<Handle, Win32Error> {
+///     call_handle_getter!(FindFirstFileW(name.as_ptr(), data))
+/// }
+/// ```
+#[macro_export]
+macro_rules! call_handle_getter {
+    ($f:ident ( $($arg:expr),* )) => {
+        {
+            use $crate::error::{ErrorCode, FileLine, ResultExt, Win32Error};
+            $crate::handle::Handle::new($f($($arg),*))
+                .map_err(Win32Error::new)
+                    .function(stringify!($f))
+                    .file_line(file!(), line!())
+        }
+    };
+
+    // support for trailing comma in argument list
+    ($f:ident ( $($arg:expr),+ , )) => {
+        $crate::call_valid_handle_getter!($f($($arg),*))
+    };
+}
diff --git a/third_party/rust/comedy/src/lib.rs b/third_party/rust/comedy/src/lib.rs
new file mode 100644
index 0000000000..3fd906ba36
--- /dev/null
+++ b/third_party/rust/comedy/src/lib.rs
@@ -0,0 +1,18 @@
+// 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.
+#![cfg(windows)]
+
+//! Windows error handling, COM, and handles
+//!
+//! See macros for examples.
+
+extern crate winapi;
+
+pub mod com;
+pub mod error;
+pub mod handle;
+
+pub use error::{HResult, ResultExt, Win32Error};