comments: add more explainations to new code

This commit is contained in:
Victor Brekenfeld 2018-12-05 16:00:01 +01:00
parent a3734da9da
commit bbe767002d
9 changed files with 32 additions and 6 deletions

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@ -63,7 +63,7 @@ where
{
/// Try to create a new `EglDevice` from an open device.
///
/// Returns an error if the file is no valid device or context
/// Returns an error if the file is no valid device or context
/// creation was not successful.
pub fn new<L>(dev: D, logger: L) -> Result<Self>
where

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@ -88,6 +88,8 @@ unsafe impl<D: RawDevice + 'static> NativeSurface for GbmSurface<D> {
}
fn swap_buffers(&self) -> ::std::result::Result<(), SwapBuffersError> {
// this is save since `eglSwapBuffers` will have been called exactly once
// if this is used by our egl module, which is why this trait is unsafe.
unsafe { self.page_flip() }
}
}

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@ -136,6 +136,7 @@ impl<D: RawDevice + ControlDevice + 'static> Device for GbmDevice<D> {
let drm_surface = Device::create_surface(&mut **self.dev.borrow_mut(), crtc)
.chain_err(|| ErrorKind::UnderlyingBackendError)?;
// initialize the surface
let (w, h) = drm_surface
.pending_mode()
.map(|mode| mode.size())
@ -150,6 +151,7 @@ impl<D: RawDevice + ControlDevice + 'static> Device for GbmDevice<D> {
BufferObjectFlags::SCANOUT | BufferObjectFlags::RENDERING,
).chain_err(|| ErrorKind::SurfaceCreationFailed)?;
// initialize a buffer for the cursor image
let cursor = Cell::new((
self.dev
.borrow()

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@ -284,6 +284,11 @@ pub struct GbmSurface<D: RawDevice + 'static>(pub(super) Rc<GbmSurfaceInternal<D
impl<D: RawDevice + 'static> GbmSurface<D> {
/// Flips the underlying buffers.
///
/// The surface will reported being already flipped until the matching events
/// was processed either by calling `GbmDevice::process_events` manually after the flip
/// (bad idea performance-wise) or by binding the device to an event-loop by using
/// `device_bind`.
///
/// *Note*: This might trigger a full modeset on the underlying device,
/// potentially causing some flickering. In that case this operation is
/// blocking until the crtc is in the desired state.

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@ -60,6 +60,9 @@ impl<A: AsRawFd + 'static> Drop for Dev<A> {
fn drop(&mut self) {
info!(self.logger, "Dropping device: {:?}", self.dev_path());
if self.active.load(Ordering::SeqCst) {
// Here we restore the tty to it's previous state.
// In case e.g. getty was running on the tty sets the correct framebuffer again,
// so that getty will be visible.
let old_state = self.old_state.clone();
for (handle, (info, connectors)) in old_state {
if let Err(err) = crtc::set(
@ -113,6 +116,7 @@ impl<A: AsRawFd + 'static> LegacyDrmDevice<A> {
dev.priviledged = false;
};
// enumerate (and save) the current device state
let res_handles = ControlDevice::resource_handles(&dev).chain_err(|| {
ErrorKind::DrmDev(format!("Error loading drm resources on {:?}", dev.dev_path()))
})?;
@ -138,7 +142,6 @@ impl<A: AsRawFd + 'static> LegacyDrmDevice<A> {
}
Ok(LegacyDrmDevice {
// Open the drm device and create a context based on that
dev: Rc::new(dev),
dev_id,
active,
@ -182,6 +185,8 @@ impl<A: AsRawFd + 'static> Device for LegacyDrmDevice<A> {
bail!(ErrorKind::DeviceInactive);
}
// Try to enumarate the current state to set the initial state variable correctly
let crtc_info = crtc::Info::load_from_device(self, crtc)
.chain_err(|| ErrorKind::DrmDev(format!("Error loading crtc info on {:?}", self.dev_path())))?;

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@ -3,7 +3,7 @@
//! to an open [`Session`](../../session/trait.Session.html).
//!
use drm::control::{crtc};
use drm::control::crtc;
use drm::Device as BasicDevice;
use nix::libc::dev_t;
use nix::sys::stat;
@ -52,6 +52,8 @@ impl<A: AsRawFd + 'static> SessionObserver for LegacyDrmDeviceObserver<A> {
if let Some(device) = self.dev.upgrade() {
if let Some(backends) = self.backends.upgrade() {
for surface in backends.borrow().values().filter_map(Weak::upgrade) {
// other ttys that use no cursor, might not clear it themselves.
// This makes sure our cursor won't stay visible.
let _ = crtc::clear_cursor(&*device, surface.crtc);
}
}

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@ -131,7 +131,7 @@ impl<A: AsRawFd + 'static> Surface for LegacyDrmSurfaceInternal<A> {
fn use_mode(&self, mode: Option<Mode>) -> Result<()> {
let mut pending = self.pending.write().unwrap();
// check the connectors
// check the connectors to see if this mode is supported
if let Some(mode) = mode {
for connector in &pending.connectors {
if !connector::Info::load_from_device(self, *connector)
@ -236,6 +236,15 @@ impl<A: AsRawFd + 'static> Drop for LegacyDrmSurfaceInternal<A> {
/// Open raw crtc utilizing legacy mode-setting
pub struct LegacyDrmSurface<A: AsRawFd + 'static>(pub(super) Rc<LegacyDrmSurfaceInternal<A>>);
impl<A: AsRawFd + 'static> AsRawFd for LegacyDrmSurface<A> {
fn as_raw_fd(&self) -> RawFd {
self.0.as_raw_fd()
}
}
impl<A: AsRawFd + 'static> BasicDevice for LegacyDrmSurface<A> {}
impl<A: AsRawFd + 'static> ControlDevice for LegacyDrmSurface<A> {}
impl<'a, A: AsRawFd + 'static> CursorBackend<'a> for LegacyDrmSurface<A> {
type CursorFormat = &'a Buffer;
type Error = Error;

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@ -36,8 +36,9 @@
//!
pub use drm::{
control::{connector, crtc, framebuffer, Device as ControlDevice, Mode, ResourceHandles, ResourceInfo},
Device as BasicDevice,
buffer::Buffer,
control::{connector, crtc, framebuffer, Mode, ResourceHandles, ResourceInfo, Device as ControlDevice},
};
pub use nix::libc::dev_t;

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@ -49,7 +49,7 @@ pub trait GLGraphicsBackend {
///
/// This remains valid as long as the underlying `GLGraphicsBackend` is alive
/// and may only be used in combination with the backend. Using this with any
/// other gl context may cause undefined behavior.
/// other gl context *may* cause undefined behavior.
pub fn load_raw_gl<B: GLGraphicsBackend>(backend: &B) -> Gles2 {
Gles2::load_with(|s| unsafe { backend.get_proc_address(s) as *const _ })
}