Merge pull request #452 from mbiggio/wip/biggio/shared-macro

glib: glib-macros: add SharedType and Shared derive macro

Author: sdroege

.github/workflows/CI.yml

@@ -17,7 +17,7 @@ jobs:
           - stable
           - beta
           - nightly
-          - "1.48.0"
+          - "1.51.0"
         conf:
           - { name: "atk", features: "v2_34", nightly: "--all-features", test_sys: true }
           - { name: "cairo", features: "png,pdf,svg,ps,use_glib,v1_16,freetype,script,xcb,xlib,win32-surface", nightly: "--features 'png,pdf,svg,ps,use_glib,v1_16,freetype,script,xcb,xlib,win32-surface'", test_sys: true }
@@ -119,7 +119,7 @@ jobs:
           - stable
           - beta
           - nightly
-          - "1.48.0"
+          - "1.51.0"
     steps:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1

README.md

@@ -8,7 +8,7 @@ information about each crate, please refer to their `README.md` file in their di
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

atk/README.md

@@ -5,7 +5,7 @@ __Rust__ bindings and wrappers for __Atk__, part of [gtk-rs](https://github.com/
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

cairo/README.md

@@ -6,7 +6,7 @@ __Rust__ bindings for Rust and wrappers for __Cairo__.
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

gdk-pixbuf/README.md

@@ -4,7 +4,7 @@ __Rust__ bindings and wrappers for __Gdk-Pixbuf__.
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

gdk/README.md

@@ -4,7 +4,7 @@ __Rust__ bindings and wrappers for __GDK__, part of [gtk-rs](https://github.com/
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

gdkx11/README.md

@@ -4,7 +4,7 @@ __Rust__ bindings and wrappers for __GDKX11__, part of [gtk-rs](https://github.c
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

gio/README.md

@@ -4,7 +4,7 @@ __Rust__ bindings and wrappers for __GIO__, part of [gtk-rs](https://github.com/
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation
 

glib-macros/src/gboxed_shared_derive.rs

@@ -0,0 +1,181 @@
+// Take a look at the license at the top of the repository in the LICENSE file.
+
+use crate::utils::{crate_ident_new, find_attribute_meta, find_nested_meta, parse_type_name};
+use proc_macro2::{Ident, TokenStream};
+use proc_macro_error::abort_call_site;
+use quote::quote;
+
+fn gen_impl_set_value_optional(name: &Ident, crate_ident: &Ident) -> TokenStream {
+    let refcounted_type_prefix = refcounted_type_prefix(name, crate_ident);
+
+    quote! {
+        impl #crate_ident::value::SetValueOptional for #name {
+            unsafe fn set_value_optional(value: &mut #crate_ident::value::Value, this: Option<&Self>) {
+                let ptr = match this {
+                    Some(this) => #refcounted_type_prefix::into_raw(this.0.clone()),
+                    None => std::ptr::null(),
+                };
+
+                #crate_ident::gobject_ffi::g_value_take_boxed(
+                    #crate_ident::translate::ToGlibPtrMut::to_glib_none_mut(value).0,
+                    ptr as *mut _,
+                );
+            }
+        }
+    }
+}
+
+fn gen_impl_from_value(name: &Ident, crate_ident: &Ident) -> TokenStream {
+    let refcounted_type_prefix = refcounted_type_prefix(name, crate_ident);
+
+    quote! {
+        impl<'a> #crate_ident::value::FromValue<'a> for #name {
+            unsafe fn from_value(value: &'a #crate_ident::value::Value) -> Self {
+                let ptr = #crate_ident::gobject_ffi::g_value_dup_boxed(
+                    #crate_ident::translate::ToGlibPtr::to_glib_none(value).0,
+                );
+                assert!(!ptr.is_null());
+                #name(#refcounted_type_prefix::from_raw(ptr as *mut _))
+            }
+        }
+    }
+}
+
+fn gen_ptr_to_option(name: &Ident, nullable: bool, crate_ident: &Ident) -> TokenStream {
+    let refcounted_type_prefix = refcounted_type_prefix(name, crate_ident);
+
+    if nullable {
+        quote! {
+            if ptr.is_null() {
+                None
+            } else {
+                Some(#name(#refcounted_type_prefix::from_raw(ptr as *mut _)))
+            }
+        }
+    } else {
+        quote! {
+            assert!(!ptr.is_null());
+            Some(#name(#refcounted_type_prefix::from_raw(ptr as *mut _)))
+        }
+    }
+}
+
+fn refcounted_type(input: &syn::DeriveInput) -> Option<&syn::TypePath> {
+    let fields = match &input.data {
+        syn::Data::Struct(s) => &s.fields,
+        _ => return None,
+    };
+
+    let unnamed = match fields {
+        syn::Fields::Unnamed(u) if u.unnamed.len() == 1 => &u.unnamed[0],
+        _ => return None,
+    };
+
+    let refcounted = match &unnamed.ty {
+        syn::Type::Path(p) => p,
+        _ => return None,
+    };
+
+    Some(refcounted)
+}
+
+fn refcounted_type_prefix(name: &Ident, crate_ident: &Ident) -> proc_macro2::TokenStream {
+    quote! {
+        <<#name as #crate_ident::subclass::shared::SharedType>::RefCountedType as #crate_ident::subclass::shared::RefCounted>
+    }
+}
+
+pub fn impl_gshared_boxed(input: &syn::DeriveInput) -> proc_macro2::TokenStream {
+    let refcounted_type = match refcounted_type(input) {
+        Some(p) => p,
+        _ => abort_call_site!("derive(GSharedBoxed) requires struct MyStruct(T: RefCounted)"),
+    };
+
+    let name = &input.ident;
+    let gtype_name = match parse_type_name(&input, "gshared_boxed") {
+        Ok(v) => v,
+        Err(e) => abort_call_site!(
+            "{}: derive(GSharedBoxed) requires #[gshared_boxed(type_name = \"SharedTypeName\")]",
+            e
+        ),
+    };
+
+    let meta = find_attribute_meta(&input.attrs, "gshared_boxed")
+        .unwrap()
+        .unwrap();
+    let nullable = find_nested_meta(&meta, "nullable").is_some();
+    let crate_ident = crate_ident_new();
+    let refcounted_type_prefix = refcounted_type_prefix(name, &crate_ident);
+    let ptr_to_option = gen_ptr_to_option(name, nullable, &crate_ident);
+
+    let impl_from_value = if !nullable {
+        gen_impl_from_value(name, &crate_ident)
+    } else {
+        quote! {}
+    };
+
+    let impl_set_value_optional = if nullable {
+        gen_impl_set_value_optional(name, &crate_ident)
+    } else {
+        quote! {}
+    };
+
+    quote! {
+        impl #crate_ident::subclass::shared::SharedType for #name {
+            const NAME: &'static str = #gtype_name;
+
+            type RefCountedType = #refcounted_type;
+
+            fn get_type() -> #crate_ident::Type {
+                static mut TYPE_: #crate_ident::Type = #crate_ident::Type::INVALID;
+                static ONCE: ::std::sync::Once = ::std::sync::Once::new();
+
+                ONCE.call_once(|| {
+                    let type_ = #crate_ident::subclass::shared::register_shared_type::<Self>();
+                    unsafe {
+                        TYPE_ = type_;
+                    }
+                });
+
+                unsafe { TYPE_ }
+            }
+
+            fn from_refcounted(this: Self::RefCountedType) -> Self {
+                Self(this)
+            }
+
+            fn into_refcounted(self) -> Self::RefCountedType {
+                self.0
+            }
+        }
+
+        impl #crate_ident::StaticType for #name {
+            fn static_type() -> #crate_ident::Type {
+                <#name as #crate_ident::subclass::shared::SharedType>::get_type()
+            }
+        }
+
+        impl #crate_ident::value::SetValue for #name {
+            unsafe fn set_value(value: &mut #crate_ident::value::Value, this: &Self) {
+                let ptr = #refcounted_type_prefix::into_raw(this.0.clone());
+                #crate_ident::gobject_ffi::g_value_take_boxed(
+                    #crate_ident::translate::ToGlibPtrMut::to_glib_none_mut(value).0,
+                    ptr as *mut _,
+                );
+            }
+        }
+
+        #impl_set_value_optional
+
+        impl<'a> #crate_ident::value::FromValueOptional<'a> for #name {
+            unsafe fn from_value_optional(value: &'a #crate_ident::value::Value) -> Option<Self> {
+                let ptr = #crate_ident::gobject_ffi::g_value_dup_boxed(
+                    #crate_ident::translate::ToGlibPtr::to_glib_none(value).0,
+                );
+                #ptr_to_option
+            }
+        }
+
+        #impl_from_value
+    }
+}

glib-macros/src/lib.rs

@@ -3,6 +3,7 @@
 mod clone;
 mod downgrade_derive;
 mod gboxed_derive;
+mod gboxed_shared_derive;
 mod genum_derive;
 mod gerror_domain_derive;
 mod gflags_attribute;
@@ -300,6 +301,34 @@ pub fn gboxed_derive(input: TokenStream) -> TokenStream {
     gen.into()
 }
 
+/// Derive macro for defining a [`SharedType`]`::get_type` function and
+/// the [`glib::Value`] traits.
+///
+/// # Example
+///
+/// ```
+/// use glib::prelude::*;
+/// use glib::subclass::prelude::*;
+///
+/// #[derive(Clone, Debug, PartialEq, Eq)]
+/// struct MySharedInner {
+///   foo: String,
+/// }
+/// #[derive(Clone, Debug, PartialEq, Eq, glib::GSharedBoxed)]
+/// #[gshared_boxed(type_name = "MyShared")]
+/// struct MyShared(std::sync::Arc<MySharedInner>);
+/// ```
+///
+/// [`SharedType`]: subclass/shared/trait.SharedType.html
+/// [`glib::Value`]: value/struct.Value.html
+#[proc_macro_derive(GSharedBoxed, attributes(gshared_boxed))]
+#[proc_macro_error]
+pub fn gshared_boxed_derive(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+    let gen = gboxed_shared_derive::impl_gshared_boxed(&input);
+    gen.into()
+}
+
 /// Attribute macro for defining flags using the `bitflags` crate.
 /// This macro will also define a `GFlags::get_type` function and
 /// the [`glib::Value`] traits.

glib-macros/tests/test.rs

@@ -5,7 +5,7 @@
 use glib::prelude::*;
 use glib::subclass::prelude::*;
 use glib::translate::{FromGlib, ToGlib};
-use glib::{gflags, GBoxed, GEnum, GErrorDomain};
+use glib::{gflags, GBoxed, GEnum, GErrorDomain, GSharedBoxed};
 
 #[test]
 fn derive_gerror_domain() {
@@ -22,6 +22,72 @@ fn derive_gerror_domain() {
     assert!(matches!(err.kind::<TestError>(), Some(TestError::Bad)));
 }
 
+#[test]
+fn derive_shared_arc() {
+    #[derive(Debug, Eq, PartialEq, Clone)]
+    struct MyInnerShared {
+        foo: String,
+    }
+    #[derive(Debug, Eq, PartialEq, Clone, GSharedBoxed)]
+    #[gshared_boxed(type_name = "MySharedType")]
+    struct MyShared(std::sync::Arc<MyInnerShared>);
+
+    assert_eq!(MyShared::get_type().name(), "MySharedType");
+
+    let p = MyShared(std::sync::Arc::new(MyInnerShared {
+        foo: String::from("bar"),
+    }));
+
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 1);
+    let v = p.to_value();
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 2);
+    let p_clone = v.get::<MyShared>().unwrap().unwrap();
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 3);
+    drop(p_clone);
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 2);
+    drop(v);
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 1);
+}
+
+#[test]
+fn derive_shared_arc_nullable() {
+    #[derive(Debug, Eq, PartialEq, Clone)]
+    struct MyInnerNullableShared {
+        foo: String,
+    }
+    #[derive(Clone, Debug, PartialEq, Eq, GSharedBoxed)]
+    #[gshared_boxed(type_name = "MyNullableSharedType", nullable)]
+    struct MyNullableShared(std::sync::Arc<MyInnerNullableShared>);
+
+    assert_eq!(MyNullableShared::get_type().name(), "MyNullableSharedType");
+
+    let p = MyNullableShared(std::sync::Arc::new(MyInnerNullableShared {
+        foo: String::from("bar"),
+    }));
+
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 1);
+    let _v = p.to_value();
+    assert_eq!(std::sync::Arc::strong_count(&p.0), 2);
+
+    let p = Some(MyNullableShared(std::sync::Arc::new(
+        MyInnerNullableShared {
+            foo: String::from("foo"),
+        },
+    )));
+
+    assert_eq!(std::sync::Arc::strong_count(&p.as_ref().unwrap().0), 1);
+    let v = p.to_value();
+    assert_eq!(std::sync::Arc::strong_count(&p.as_ref().unwrap().0), 2);
+    assert_eq!(
+        p.as_ref().unwrap().0.foo,
+        v.get::<MyNullableShared>().unwrap().unwrap().0.foo
+    );
+
+    let b: Option<MyNullableShared> = None;
+    let v = b.to_value();
+    assert_eq!(None, v.get::<MyNullableShared>().unwrap());
+}
+
 #[test]
 fn derive_genum() {
     #[derive(Debug, Eq, PartialEq, Clone, Copy, GEnum)]

glib/README.md

@@ -4,7 +4,7 @@ __Rust__ bindings and wrappers for __GLib__, part of [gtk-rs](https://github.com
 
 ## Minimum supported Rust version
 
-Currently, the minimum supported Rust version is `1.48.0`.
+Currently, the minimum supported Rust version is `1.51.0`.
 
 ## Documentation