gstreamer/subclass/
device_provider.rs

1// Take a look at the license at the top of the repository in the LICENSE file.
2
3use std::borrow::Cow;
4
5use glib::{prelude::*, subclass::prelude::*, translate::*};
6
7use super::prelude::*;
8use crate::{ffi, Device, DeviceProvider, LoggableError};
9
10#[derive(Debug, Clone)]
11pub struct DeviceProviderMetadata {
12    long_name: Cow<'static, str>,
13    classification: Cow<'static, str>,
14    description: Cow<'static, str>,
15    author: Cow<'static, str>,
16    additional: Cow<'static, [(Cow<'static, str>, Cow<'static, str>)]>,
17}
18
19impl DeviceProviderMetadata {
20    pub fn new(long_name: &str, classification: &str, description: &str, author: &str) -> Self {
21        Self {
22            long_name: Cow::Owned(long_name.into()),
23            classification: Cow::Owned(classification.into()),
24            description: Cow::Owned(description.into()),
25            author: Cow::Owned(author.into()),
26            additional: Cow::Borrowed(&[]),
27        }
28    }
29
30    pub fn with_additional(
31        long_name: &str,
32        classification: &str,
33        description: &str,
34        author: &str,
35        additional: &[(&str, &str)],
36    ) -> Self {
37        Self {
38            long_name: Cow::Owned(long_name.into()),
39            classification: Cow::Owned(classification.into()),
40            description: Cow::Owned(description.into()),
41            author: Cow::Owned(author.into()),
42            additional: additional
43                .iter()
44                .copied()
45                .map(|(key, value)| (Cow::Owned(key.into()), Cow::Owned(value.into())))
46                .collect(),
47        }
48    }
49
50    pub const fn with_cow(
51        long_name: Cow<'static, str>,
52        classification: Cow<'static, str>,
53        description: Cow<'static, str>,
54        author: Cow<'static, str>,
55        additional: Cow<'static, [(Cow<'static, str>, Cow<'static, str>)]>,
56    ) -> Self {
57        Self {
58            long_name,
59            classification,
60            description,
61            author,
62            additional,
63        }
64    }
65}
66
67pub trait DeviceProviderImpl: GstObjectImpl + ObjectSubclass<Type: IsA<DeviceProvider>> {
68    fn metadata() -> Option<&'static DeviceProviderMetadata> {
69        None
70    }
71
72    fn probe(&self) -> Vec<Device> {
73        self.parent_probe()
74    }
75
76    fn start(&self) -> Result<(), LoggableError> {
77        self.parent_start()
78    }
79
80    fn stop(&self) {
81        self.parent_stop()
82    }
83}
84
85pub trait DeviceProviderImplExt: DeviceProviderImpl {
86    fn parent_probe(&self) -> Vec<Device> {
87        unsafe {
88            let data = Self::type_data();
89            let parent_class = data.as_ref().parent_class() as *mut ffi::GstDeviceProviderClass;
90            if let Some(f) = (*parent_class).probe {
91                FromGlibPtrContainer::from_glib_full(f(self
92                    .obj()
93                    .unsafe_cast_ref::<DeviceProvider>()
94                    .to_glib_none()
95                    .0))
96            } else {
97                Vec::new()
98            }
99        }
100    }
101
102    fn parent_start(&self) -> Result<(), LoggableError> {
103        unsafe {
104            let data = Self::type_data();
105            let parent_class = data.as_ref().parent_class() as *mut ffi::GstDeviceProviderClass;
106            let f = (*parent_class).start.ok_or_else(|| {
107                loggable_error!(crate::CAT_RUST, "Parent function `start` is not defined")
108            })?;
109            result_from_gboolean!(
110                f(self
111                    .obj()
112                    .unsafe_cast_ref::<DeviceProvider>()
113                    .to_glib_none()
114                    .0),
115                crate::CAT_RUST,
116                "Failed to start the device provider using the parent function"
117            )
118        }
119    }
120
121    fn parent_stop(&self) {
122        unsafe {
123            let data = Self::type_data();
124            let parent_class = data.as_ref().parent_class() as *mut ffi::GstDeviceProviderClass;
125            if let Some(f) = (*parent_class).stop {
126                f(self
127                    .obj()
128                    .unsafe_cast_ref::<DeviceProvider>()
129                    .to_glib_none()
130                    .0);
131            }
132        }
133    }
134}
135
136impl<T: DeviceProviderImpl> DeviceProviderImplExt for T {}
137
138unsafe impl<T: DeviceProviderImpl> IsSubclassable<T> for DeviceProvider {
139    fn class_init(klass: &mut glib::Class<Self>) {
140        Self::parent_class_init::<T>(klass);
141        let klass = klass.as_mut();
142        klass.probe = Some(device_provider_probe::<T>);
143        klass.start = Some(device_provider_start::<T>);
144        klass.stop = Some(device_provider_stop::<T>);
145
146        unsafe {
147            if let Some(metadata) = T::metadata() {
148                ffi::gst_device_provider_class_set_metadata(
149                    klass,
150                    metadata.long_name.to_glib_none().0,
151                    metadata.classification.to_glib_none().0,
152                    metadata.description.to_glib_none().0,
153                    metadata.author.to_glib_none().0,
154                );
155
156                for (key, value) in metadata.additional.iter() {
157                    ffi::gst_device_provider_class_add_metadata(
158                        klass,
159                        key.to_glib_none().0,
160                        value.to_glib_none().0,
161                    );
162                }
163            }
164        }
165    }
166}
167
168unsafe extern "C" fn device_provider_probe<T: DeviceProviderImpl>(
169    ptr: *mut ffi::GstDeviceProvider,
170) -> *mut glib::ffi::GList {
171    let instance = &*(ptr as *mut T::Instance);
172    let imp = instance.imp();
173
174    imp.probe().to_glib_full()
175}
176
177unsafe extern "C" fn device_provider_start<T: DeviceProviderImpl>(
178    ptr: *mut ffi::GstDeviceProvider,
179) -> glib::ffi::gboolean {
180    let instance = &*(ptr as *mut T::Instance);
181    let imp = instance.imp();
182
183    match imp.start() {
184        Ok(()) => true,
185        Err(err) => {
186            err.log_with_imp(imp);
187            false
188        }
189    }
190    .into_glib()
191}
192
193unsafe extern "C" fn device_provider_stop<T: DeviceProviderImpl>(ptr: *mut ffi::GstDeviceProvider) {
194    let instance = &*(ptr as *mut T::Instance);
195    let imp = instance.imp();
196
197    imp.stop();
198}
gstreamer/subclass/device_provider.rs

gstreamer/subclass/
device_provider.rs
