Improve HRESULT ergonomics (#2843)

microsoft · Feb 13, 2024 · 7ce7894 · 7ce7894
1 parent ed2ef0d
commit 7ce7894
Show file tree

Hide file tree

Showing 529 changed files with 52,162 additions and 52,147 deletions.
diff --git a/crates/libs/bindgen/src/rust/com_methods.rs b/crates/libs/bindgen/src/rust/com_methods.rs
@@ -33,7 +33,7 @@ pub fn writer(writer: &Writer, def: metadata::TypeDef, kind: metadata::Interface
                 #features
                 pub unsafe fn #name<#generics>(&self, #params) -> ::windows_core::Result<T> #where_clause {
                     let mut result__ = ::std::ptr::null_mut();
-                    (::windows_core::Interface::vtable(self)#bases.#vname)(::windows_core::Interface::as_raw(self), #args).from_abi(result__)
+                    (::windows_core::Interface::vtable(self)#bases.#vname)(::windows_core::Interface::as_raw(self), #args).and_then(||::windows_core::Type::from_abi(result__))
                 }
             }
         }
@@ -54,13 +54,20 @@ pub fn writer(writer: &Writer, def: metadata::TypeDef, kind: metadata::Interface
             let args = writer.win32_args(&signature.params, kind);
             let params = writer.win32_params(&signature.params, kind);
             let return_type = signature.params[signature.params.len() - 1].ty.deref();
+
+            let map = if metadata::type_is_blittable(&return_type) {
+                quote! { map(||result__) }
+            } else {
+                quote! { and_then(||::windows_core::Type::from_abi(result__)) }
+            };
+
             let return_type = writer.type_name(&return_type);
 
             quote! {
                 #features
                 pub unsafe fn #name<#generics>(&self, #params) -> ::windows_core::Result<#return_type> #where_clause {
                     let mut result__ = ::std::mem::zeroed();
-                    (::windows_core::Interface::vtable(self)#bases.#vname)(::windows_core::Interface::as_raw(self), #args).from_abi(result__)
+                    (::windows_core::Interface::vtable(self)#bases.#vname)(::windows_core::Interface::as_raw(self), #args).#map
                 }
             }
         }
@@ -80,24 +87,33 @@ pub fn writer(writer: &Writer, def: metadata::TypeDef, kind: metadata::Interface
             let params = writer.win32_params(&signature.params, kind);
             let return_type = signature.params[signature.params.len() - 1].ty.deref();
             let is_nullable = metadata::type_is_nullable(&return_type);
-            let return_type = writer.type_name(&return_type);
 
             if is_nullable {
+                let return_type = writer.type_name(&return_type);
+
                 quote! {
                     #features
                     pub unsafe fn #name<#generics>(&self, #params) -> ::windows_core::Result<#return_type> #where_clause {
                         let mut result__ = ::std::mem::zeroed();
                         (::windows_core::Interface::vtable(self)#bases.#vname)(::windows_core::Interface::as_raw(self), #args);
-                        ::windows_core::from_abi(result__)
+                        ::windows_core::Type::from_abi(result__)
                     }
                 }
             } else {
+                let map = if metadata::type_is_blittable(&return_type) {
+                    quote! { result__ }
+                } else {
+                    quote! { ::std::mem::transmute(result__) }
+                };
+
+                let return_type = writer.type_name(&return_type);
+
                 quote! {
                     #features
                     pub unsafe fn #name<#generics>(&self, #params) -> #return_type #where_clause {
                         let mut result__ = ::std::mem::zeroed();
                         (::windows_core::Interface::vtable(self)#bases.#vname)(::windows_core::Interface::as_raw(self), #args);
-                        ::std::mem::transmute(result__)
+                        #map
                     }
                 }
             }

diff --git a/crates/libs/bindgen/src/rust/functions.rs b/crates/libs/bindgen/src/rust/functions.rs
@@ -53,7 +53,7 @@ fn gen_win_function(writer: &Writer, namespace: &str, def: metadata::MethodDef)
                 pub unsafe fn #name<#generics>(#params) -> ::windows_core::Result<T> #where_clause {
                     #link
                     let mut result__ = ::std::ptr::null_mut();
-                    #name(#args).from_abi(result__)
+                    #name(#args).and_then(||::windows_core::Type::from_abi(result__))
                 }
             }
         }
@@ -76,6 +76,13 @@ fn gen_win_function(writer: &Writer, namespace: &str, def: metadata::MethodDef)
             let args = writer.win32_args(&signature.params, kind);
             let params = writer.win32_params(&signature.params, kind);
             let return_type = signature.params[signature.params.len() - 1].ty.deref();
+
+            let map = if metadata::type_is_blittable(&return_type) {
+                quote! { map(||result__) }
+            } else {
+                quote! { and_then(||::windows_core::Type::from_abi(result__)) }
+            };
+
             let return_type = writer.type_name(&return_type);
 
             quote! {
@@ -84,7 +91,7 @@ fn gen_win_function(writer: &Writer, namespace: &str, def: metadata::MethodDef)
                 pub unsafe fn #name<#generics>(#params) -> ::windows_core::Result<#return_type> #where_clause {
                     #link
                     let mut result__ = ::std::mem::zeroed();
-                    #name(#args).from_abi(result__)
+                    #name(#args).#map
                 }
             }
         }
@@ -106,28 +113,37 @@ fn gen_win_function(writer: &Writer, namespace: &str, def: metadata::MethodDef)
             let params = writer.win32_params(&signature.params, kind);
             let return_type = signature.params[signature.params.len() - 1].ty.deref();
             let is_nullable = metadata::type_is_nullable(&return_type);
-            let return_type = writer.type_name(&return_type);
 
             if is_nullable {
+                let return_type = writer.type_name(&return_type);
+
                 quote! {
                     #features
                     #[inline]
                     pub unsafe fn #name<#generics>(#params) -> ::windows_core::Result<#return_type> #where_clause {
                         #link
                         let mut result__ = ::std::mem::zeroed();
                         #name(#args);
-                        ::windows_core::from_abi(result__.assume_init())
+                        ::windows_core::Type::from_abi(result__.assume_init())
                     }
                 }
             } else {
+                let map = if metadata::type_is_blittable(&return_type) {
+                    quote! { result__ }
+                } else {
+                    quote! { ::std::mem::transmute(result__) }
+                };
+
+                let return_type = writer.type_name(&return_type);
+
                 quote! {
                     #features
                     #[inline]
                     pub unsafe fn #name<#generics>(#params) -> #return_type #where_clause {
                         #link
                         let mut result__ = ::std::mem::zeroed();
                         #name(#args);
-                        ::std::mem::transmute(result__)
+                        #map
                     }
                 }
             }

diff --git a/crates/libs/bindgen/src/rust/winrt_methods.rs b/crates/libs/bindgen/src/rust/winrt_methods.rs
@@ -49,14 +49,20 @@ pub fn writer(writer: &Writer, def: metadata::TypeDef, generic_types: &[metadata
             quote! {
                 let mut result__ = ::core::mem::MaybeUninit::zeroed();
                 (::windows_core::Interface::vtable(this).#vname)(::windows_core::Interface::as_raw(this), #args #return_arg)
-                    .and_then(|| result__.assume_init())
+                    .map(|| result__.assume_init())
             }
         }
         _ => {
+            let map = if metadata::type_is_blittable(&signature.return_type) {
+                quote! { map(||result__) }
+            } else {
+                quote! { and_then(|| ::windows_core::Type::from_abi(result__)) }
+            };
+
             quote! {
                 let mut result__ = ::std::mem::zeroed();
                     (::windows_core::Interface::vtable(this).#vname)(::windows_core::Interface::as_raw(this), #args #return_arg)
-                        .from_abi(result__)
+                        .#map
             }
         }
     };

diff --git a/crates/libs/core/src/hresult.rs b/crates/libs/core/src/hresult.rs
@@ -40,44 +40,26 @@ impl HRESULT {
         }
     }
 
-    /// Returns the [`Option`] as a [`Result`] if the option is a [`Some`] value, returning
-    /// a suitable error if not.
-    pub fn and_some<T: Interface>(self, some: Option<T>) -> Result<T> {
-        if self.is_ok() {
-            if let Some(result) = some {
-                Ok(result)
-            } else {
-                Err(Error::OK)
-            }
-        } else {
-            Err(Error::from(self))
-        }
-    }
-
     /// Calls `op` if `self` is a success code, otherwise returns [`HRESULT`]
     /// converted to [`Result<T>`].
     #[inline]
-    pub fn and_then<F, T>(self, op: F) -> Result<T>
+    pub fn map<F, T>(self, op: F) -> Result<T>
     where
         F: FnOnce() -> T,
     {
         self.ok()?;
         Ok(op())
     }
 
-    /// If the [`Result`] is [`Ok`] converts the `T::Abi` into `T`.
-    ///
-    /// # Safety
-    ///
-    /// Safe to call if
-    /// * `abi` is initialized if `self` is `Ok`
-    /// * `abi` can be safely transmuted to `T`
-    pub unsafe fn from_abi<T: Type<T>>(self, abi: T::Abi) -> Result<T> {
-        if self.is_ok() {
-            T::from_abi(abi)
-        } else {
-            Err(Error::from(self))
-        }
+    /// Calls `op` if `self` is a success code, otherwise returns [`HRESULT`]
+    /// converted to [`Result<T>`].
+    #[inline]
+    pub fn and_then<F, T>(self, op: F) -> Result<T>
+    where
+        F: FnOnce() -> Result<T>,
+    {
+        self.ok()?;
+        op()
     }
 
     /// The error message describing the error.