Merge branch 'master' into 'master'

init: misc changes for GPU drivers

See merge request redox-os/init!7

src/main.rs

@@ -78,6 +78,36 @@ pub fn run(file: &Path) -> Result<()> {
                         println!("init: failed to run: no argument");
                     },
                     "run.d" => if let Some(new_dir) = args.next() {
+                        // On startup, the VESA display driver is started which basically makes use of the framebuffer
+                        // provided by the firmware. The GPU device are latter started by `pcid` (such as `virtio-gpu`).
+                        let mut devices = vec![];
+                        let schemes = std::fs::read_dir(":").unwrap();
+                    
+                        for entry in schemes {
+                            let path = entry.unwrap().path();
+                            let path_str = path
+                                .into_os_string()
+                                .into_string()
+                                .expect("init: failed to convert path to string");
+                    
+                            if path_str.contains("display") {
+                                println!("init: found display scheme {}", path_str);
+                                devices.push(path_str);
+                            }
+                        }
+                    
+                        let device = devices.iter().filter(|d| !d.contains("vesa")).collect::<Vec<_>>();
+                        let device = if device.is_empty() {
+                            // No GPU available, fallback to VESA display which *should* always be accessible.
+                           "vesa"
+                        } else {
+                            // :/display/virtio-gpu
+                            //           ^^^^^^^^^^
+                            device[0].split("/").nth(2).unwrap()
+                        };
+
+                        std::env::set_var("DISPLAY", &format!("display/{}:3/activate", device));
+
                         let mut entries = vec![];
                         match read_dir(&new_dir) {
                             Ok(list) => for entry_res in list {