Add gio::Vfs subclass

Signed-off-by: fbrouille <[email protected]>

Author: fbrouille

gio/src/subclass/mod.rs

@@ -12,6 +12,7 @@ mod list_model;
 mod output_stream;
 mod seekable;
 mod socket_control_message;
+mod vfs;
 
 pub use self::application::ArgumentList;
 
@@ -32,5 +33,6 @@ pub mod prelude {
         output_stream::{OutputStreamImpl, OutputStreamImplExt},
         seekable::{SeekableImpl, SeekableImplExt},
         socket_control_message::{SocketControlMessageImpl, SocketControlMessageImplExt},
+        vfs::{VfsImpl, VfsImplExt},
     };
 }

gio/src/subclass/vfs.rs

@@ -0,0 +1,337 @@
+// Take a look at the license at the top of the repository in the LICENSE file.
+
+use std::path::PathBuf;
+
+use glib::{prelude::*, subclass::prelude::*, translate::*, GString, GStringPtr, StrV};
+
+use libc::c_char;
+
+use crate::{ffi, File, Vfs};
+
+// Support custom implementation of virtual functions defined in `gio::ffi::GVfsClass`.
+pub trait VfsImpl: ObjectImpl + ObjectSubclass<Type: IsA<Vfs>> {
+    fn is_active(&self) -> bool {
+        self.parent_is_active()
+    }
+
+    fn get_file_for_path(&self, path: &std::path::Path) -> File {
+        self.parent_get_file_for_path(path)
+    }
+
+    fn get_file_for_uri(&self, uri: &str) -> File {
+        self.parent_get_file_for_uri(uri)
+    }
+
+    // rustdoc-stripper-ignore-next
+    /// Gets a list of URI schemes supported by vfs.
+    ///
+    /// # Safety
+    ///
+    /// Implementation has to ensure it returns a `&'static [GStringPtr]` that is a `NULL`-terminated C array,
+    /// e.g. by building a `static LazyLock<StrV>` that derefs into `&'static [glib::GStringPtr]`.
+    unsafe fn get_supported_uri_schemes(&self) -> &'static [GStringPtr] {
+        self.parent_get_supported_uri_schemes()
+    }
+
+    fn parse_name(&self, parse_name: &str) -> File {
+        self.parent_parse_name(parse_name)
+    }
+}
+
+// Support parent implementation of virtual functions defined in `gio::ffi::GVfsClass`.
+pub trait VfsImplExt: VfsImpl {
+    fn parent_is_active(&self) -> bool {
+        unsafe {
+            let data = Self::type_data();
+            let parent_class = data.as_ref().parent_class() as *const ffi::GVfsClass;
+
+            let f = (*parent_class)
+                .is_active
+                .expect("No parent class implementation for \"is_active\"");
+
+            let res = f(self.obj().unsafe_cast_ref::<Vfs>().to_glib_none().0);
+            from_glib(res)
+        }
+    }
+
+    fn parent_get_file_for_path(&self, path: &std::path::Path) -> File {
+        unsafe {
+            let data = Self::type_data();
+            let parent_class = data.as_ref().parent_class() as *const ffi::GVfsClass;
+
+            let f = (*parent_class)
+                .get_file_for_path
+                .expect("No parent class implementation for \"get_file_for_path\"");
+
+            let res = f(
+                self.obj().unsafe_cast_ref::<Vfs>().to_glib_none().0,
+                path.to_glib_none().0,
+            );
+            from_glib_full(res)
+        }
+    }
+
+    fn parent_get_file_for_uri(&self, uri: &str) -> File {
+        unsafe {
+            let data = Self::type_data();
+            let parent_class = data.as_ref().parent_class() as *const ffi::GVfsClass;
+
+            let f = (*parent_class)
+                .get_file_for_uri
+                .expect("No parent class implementation for \"get_file_for_uri\"");
+
+            let res = f(
+                self.obj().unsafe_cast_ref::<Vfs>().to_glib_none().0,
+                uri.to_glib_none().0,
+            );
+            from_glib_full(res)
+        }
+    }
+
+    fn parent_get_supported_uri_schemes(&self) -> &'static [GStringPtr] {
+        unsafe {
+            let data = Self::type_data();
+            let parent_class = data.as_ref().parent_class() as *const ffi::GVfsClass;
+
+            let f = (*parent_class)
+                .get_supported_uri_schemes
+                .expect("No parent class implementation for \"get_supported_uri_schemes\"");
+
+            let res = f(self.obj().unsafe_cast_ref::<Vfs>().to_glib_none().0);
+            StrV::from_glib_borrow(res)
+        }
+    }
+
+    fn parent_parse_name(&self, parse_name: &str) -> File {
+        unsafe {
+            let data = Self::type_data();
+            let parent_class = data.as_ref().parent_class() as *const ffi::GVfsClass;
+
+            let f = (*parent_class)
+                .parse_name
+                .expect("No parent class implementation for \"parse_name\"");
+
+            let res = f(
+                self.obj().unsafe_cast_ref::<Vfs>().to_glib_none().0,
+                parse_name.to_glib_none().0,
+            );
+            from_glib_full(res)
+        }
+    }
+}
+
+impl<T: VfsImpl> VfsImplExt for T {}
+
+// Implement virtual functions defined in `gio::ffi::GVfsClass`.
+unsafe impl<T: VfsImpl> IsSubclassable<T> for Vfs {
+    fn class_init(class: &mut ::glib::Class<Self>) {
+        Self::parent_class_init::<T>(class);
+
+        let klass = class.as_mut();
+        klass.is_active = Some(is_active::<T>);
+        klass.get_file_for_path = Some(get_file_for_path::<T>);
+        klass.get_file_for_uri = Some(get_file_for_uri::<T>);
+        klass.get_supported_uri_schemes = Some(get_supported_uri_schemes::<T>);
+        klass.parse_name = Some(parse_name::<T>);
+    }
+}
+
+unsafe extern "C" fn is_active<T: VfsImpl>(vfs: *mut ffi::GVfs) -> glib::ffi::gboolean {
+    let instance = &*(vfs as *mut T::Instance);
+    let imp = instance.imp();
+
+    let res = imp.is_active();
+
+    res.into_glib()
+}
+
+unsafe extern "C" fn get_file_for_path<T: VfsImpl>(
+    vfs: *mut ffi::GVfs,
+    path: *const c_char,
+) -> *mut ffi::GFile {
+    let instance = &*(vfs as *mut T::Instance);
+    let imp = instance.imp();
+
+    let file = imp.get_file_for_path(&PathBuf::from_glib_none(path));
+
+    file.into_glib_ptr()
+}
+
+unsafe extern "C" fn get_file_for_uri<T: VfsImpl>(
+    vfs: *mut ffi::GVfs,
+    uri: *const c_char,
+) -> *mut ffi::GFile {
+    let instance = &*(vfs as *mut T::Instance);
+    let imp = instance.imp();
+
+    let file = imp.get_file_for_uri(&GString::from_glib_borrow(uri));
+
+    file.into_glib_ptr()
+}
+
+unsafe extern "C" fn get_supported_uri_schemes<T: VfsImpl>(
+    vfs: *mut ffi::GVfs,
+) -> *const *const c_char {
+    let instance = &*(vfs as *mut T::Instance);
+    let imp = instance.imp();
+
+    let supported_uri_schemes = imp.get_supported_uri_schemes();
+    let ptr = supported_uri_schemes.as_ptr() as *const *const c_char;
+
+    // Verify ptr is a `NULL`-terminated C array.
+    assert!((*ptr.add(supported_uri_schemes.len())).is_null(), "get_supported_uri_schemes must return a &'static [GStringPtr] that is a `NULL`-terminated C array");
+
+    ptr
+}
+
+unsafe extern "C" fn parse_name<T: VfsImpl>(
+    vfs: *mut ffi::GVfs,
+    parse_name: *const c_char,
+) -> *mut ffi::GFile {
+    let instance = &*(vfs as *mut T::Instance);
+    let imp = instance.imp();
+
+    let file = imp.parse_name(&GString::from_glib_borrow(parse_name));
+
+    file.into_glib_ptr()
+}
+
+#[cfg(test)]
+mod tests {
+    // The following tests rely on a custom type `MyLocalVfs` that extends the existing GIO type `GLocalVfs`.
+    // For each virtual method defined in class `gio::ffi::GVfsClass`, a test checks that `MyLocalVfs` and `GLocalVfs` return the same results.
+    // Note that a `MyLocalVfs` instance is built explicitly by calling `glib::Object::builder` whereas a a `GLocalVfs` instance is created by calling `gio::auto::Vfs::local`.
+
+    use super::*;
+    use crate::prelude::*;
+
+    // Binding of existing GIO type GLocalVfs.
+    mod ffi {
+        use crate::ffi;
+
+        #[derive(Copy, Clone)]
+        #[repr(C)]
+        pub struct GLocalVfs {
+            pub parent_instance: ffi::GVfs,
+        }
+
+        #[derive(Copy, Clone)]
+        #[repr(C)]
+        pub struct GLocalVfsClass {
+            pub parent_class: ffi::GVfsClass,
+        }
+    }
+
+    glib::wrapper! {
+        #[doc(alias = "GLocalVfs")]
+        pub struct LocalVfs(Object<ffi::GLocalVfs, ffi::GLocalVfsClass>) @extends Vfs;
+
+        match fn {
+            type_ => || {
+                use std::sync::Once;
+                static ONCE: Once = Once::new();
+
+                // ensure type is initialized by calling `gio::auto::File::for_path` to create a `GLocalFile` instance.
+                ONCE.call_once(|| unsafe {
+                    let _ = File::for_path("path");
+                });
+                glib::gobject_ffi::g_type_from_name("GLocalVfs".to_glib_none().0)
+            },
+        }
+    }
+
+    pub trait LocalVfsImpl: ObjectImpl + ObjectSubclass<Type: IsA<LocalVfs> + IsA<Vfs>> {}
+
+    unsafe impl<T: LocalVfsImpl + VfsImpl> IsSubclassable<T> for LocalVfs {}
+
+    // Define `MyLocalVfs` as a subclass of `GLocalVfs`.
+    mod imp {
+        use super::*;
+
+        #[derive(Default)]
+        pub struct MyLocalVfs;
+
+        #[glib::object_subclass]
+        impl ObjectSubclass for MyLocalVfs {
+            const NAME: &'static str = "MyLocalVfs";
+            type Type = super::MyLocalVfs;
+            type ParentType = LocalVfs;
+        }
+
+        impl ObjectImpl for MyLocalVfs {}
+
+        // Implements `VfsImpl` with default implementation, which calls the parent's implementation.
+        impl VfsImpl for MyLocalVfs {}
+
+        impl LocalVfsImpl for MyLocalVfs {}
+    }
+
+    glib::wrapper! {
+        pub struct MyLocalVfs(ObjectSubclass<imp::MyLocalVfs>) @extends LocalVfs, Vfs;
+    }
+
+    #[test]
+    fn vfs_is_active() {
+        // invoke `MyLocalVfs` implementation of `gio::ffi::GVfsClass::is_active`
+        let my_local_vfs = glib::Object::new::<MyLocalVfs>();
+        let active = my_local_vfs.is_active();
+
+        // invoke `LocalVfs` implementation of `gio::ffi::GVfsClass::is_active`
+        let expected = Vfs::local().is_active();
+
+        // both results should equal
+        assert_eq!(active, expected);
+    }
+
+    #[test]
+    fn vfs_get_file_for_path() {
+        // invoke `MyLocalVfs` implementation of `gio::ffi::GVfsClass::get_file_for_path`
+        let my_local_vfs = glib::Object::new::<MyLocalVfs>();
+        let file = my_local_vfs.file_for_path("/path");
+
+        // invoke `LocalVfs` implementation of `gio::ffi::GVfsClass::get_file_for_path`
+        let expected = Vfs::local().file_for_path("/path");
+
+        // both files should equal
+        assert!(file.equal(&expected));
+    }
+
+    #[test]
+    fn vfs_get_file_for_uri() {
+        // invoke `MyLocalVfs` implementation of `gio::ffi::GVfsClass::get_file_for_uri`
+        let my_local_vfs = glib::Object::new::<MyLocalVfs>();
+        let file = my_local_vfs.file_for_uri("file:///path");
+
+        // invoke `LocalVfs` implementation of `gio::ffi::GVfsClass::get_file_for_uri`
+        let expected = Vfs::local().file_for_uri("file:///path");
+
+        // both files should equal
+        assert!(file.equal(&expected));
+    }
+
+    #[test]
+    fn vfs_get_supported_uri_schemes() {
+        // invoke `MyLocalVfs` implementation of `gio::ffi::GVfsClass::supported_uri_schemes`
+        let my_local_vfs = glib::Object::new::<MyLocalVfs>();
+        let schemes = my_local_vfs.supported_uri_schemes();
+
+        // invoke `LocalVfs` implementation of `gio::ffi::GVfsClass::supported_uri_schemes`
+        let expected = Vfs::local().supported_uri_schemes();
+
+        // both results should equal
+        assert_eq!(schemes, expected);
+    }
+
+    #[test]
+    fn vfs_parse_name() {
+        // invoke `MyLocalVfs` implementation of `gio::ffi::GVfsClass::parse_name`
+        let my_local_vfs = glib::Object::new::<MyLocalVfs>();
+        let file = my_local_vfs.parse_name("file:///path");
+
+        // invoke `LocalVfs` implementation of `gio::ffi::GVfsClass::parse_name`
+        let expected = Vfs::local().parse_name("file:///path");
+
+        // both files should equal
+        assert!(file.equal(&expected));
+    }
+}