1 files changed, 58 insertions, 41 deletions

diff --git a/backend/drm/udev.c b/backend/drm/udev.c
index 6921a998..438047d6 100644
--- a/backend/drm/udev.c
+++ b/backend/drm/udev.c
@@ -16,36 +16,39 @@
 #include "backend/drm/drm.h"
 #include "common/log.h"
 
-static bool device_is_kms(struct wlr_udev *udev,
-		struct wlr_session *session,
-		struct udev_device *dev,
-		int *fd_out)
-{
-	const char *path = udev_device_get_devnode(dev);
+/* Tests if 'path' is KMS compatible by trying to open it.
+ * It leaves the open device in *fd_out it it succeeds.
+ */
+static bool device_is_kms(struct wlr_session *restrict session,
+	const char *restrict path, int *restrict fd_out) {
+
 	int fd;
 
-	if (!path)
+	if (!path) {
 		return false;
+	}
 
 	fd = wlr_session_open_file(session, path);
-	if (fd < 0)
+	if (fd < 0) {
 		return false;
+	}
 
 	drmModeRes *res = drmModeGetResources(fd);
-	if (!res)
+	if (!res) {
 		goto out_fd;
+	}
 
 	if (res->count_crtcs <= 0 || res->count_connectors <= 0 ||
-	    res->count_encoders <= 0)
+		res->count_encoders <= 0) {
+
 		goto out_res;
+	}
 
 	if (*fd_out >= 0) {
 		wlr_session_close_file(session, *fd_out);
-		free(udev->drm_path);
 	}
 
 	*fd_out = fd;
-	udev->drm_path = strdup(path);
 
 	drmModeFreeResources(res);
 	return true;
@@ -57,10 +60,10 @@ out_fd:
 	return false;
 }
 
-int wlr_udev_find_gpu(struct wlr_udev *udev, struct wlr_session *session)
-{
-	int fd = -1;
-
+/* Tries to find the primary GPU by checking for the "boot_vga" attribute.
+ * If it's not found, it returns the first valid GPU it finds.
+ */
+int wlr_udev_find_gpu(struct wlr_udev *udev, struct wlr_session *session) {
 	struct udev_enumerate *en = udev_enumerate_new(udev->udev);
 	if (!en) {
 		wlr_log(L_ERROR, "Failed to create udev enumeration");
@@ -69,16 +72,20 @@ int wlr_udev_find_gpu(struct wlr_udev *udev, struct wlr_session *session)
 
 	udev_enumerate_add_match_subsystem(en, "drm");
 	udev_enumerate_add_match_sysname(en, "card[0-9]*");
-
 	udev_enumerate_scan_devices(en);
+
 	struct udev_list_entry *entry;
+	int fd = -1;
+	char *drm_path = NULL;
+
 	udev_list_entry_foreach(entry, udev_enumerate_get_list_entry(en)) {
 		bool is_boot_vga = false;
 
 		const char *path = udev_list_entry_get_name(entry);
 		struct udev_device *dev = udev_device_new_from_syspath(udev->udev, path);
-		if (!dev)
+		if (!dev) {
 			continue;
+		}
 
 		/*
 		const char *seat = udev_device_get_property_value(dev, "ID_SEAT");
@@ -90,14 +97,15 @@ int wlr_udev_find_gpu(struct wlr_udev *udev, struct wlr_session *session)
 		}
 		*/
 
+		// This is owned by 'dev', so we don't need to free it
 		struct udev_device *pci =
 			udev_device_get_parent_with_subsystem_devtype(dev, "pci", NULL);
 
 		if (pci) {
 			const char *id = udev_device_get_sysattr_value(pci, "boot_vga");
-			if (id && strcmp(id, "1") == 0)
+			if (id && strcmp(id, "1") == 0) {
 				is_boot_vga = true;
-			//udev_device_unref(pci);
+			}
 		}
 
 		// We already have a valid GPU
@@ -106,38 +114,47 @@ int wlr_udev_find_gpu(struct wlr_udev *udev, struct wlr_session *session)
 			continue;
 		}
 
-		if (!device_is_kms(udev, session, dev, &fd)) {
+		path = udev_device_get_devnode(dev);
+		if (!device_is_kms(session, path, &fd)) {
 			udev_device_unref(dev);
 			continue;
 		}
 
+		free(drm_path);
+		drm_path = strdup(path);
+
 		udev_device_unref(dev);
 
-		if (is_boot_vga)
+		// We've found the primary GPU
+		if (is_boot_vga) {
 			break;
+		}
 	}
 
 	udev_enumerate_unref(en);
 
+	udev->drm_path = drm_path;
 	return fd;
 }
 
-static int udev_event(int fd, uint32_t mask, void *data)
-{
-	struct wlr_drm_backend *backend = data;
-	struct wlr_udev *udev = &backend->udev;
+static int udev_event(int fd, uint32_t mask, void *data) {
+	struct wlr_udev *udev = data;
+	struct wlr_drm_backend *backend = wl_container_of(udev, backend, udev);
 
 	struct udev_device *dev = udev_monitor_receive_device(udev->mon);
-	if (!dev)
+	if (!dev) {
 		return 1;
+	}
 
 	const char *path = udev_device_get_devnode(dev);
-	if (!path || strcmp(path, udev->drm_path) != 0)
+	if (!path || strcmp(path, udev->drm_path) != 0) {
 		goto out;
+	}
 
 	const char *action = udev_device_get_action(dev);
-	if (!action || strcmp(action, "change") != 0)
+	if (!action || strcmp(action, "change") != 0) {
 		goto out;
+	}
 
 	wlr_drm_scan_connectors(backend);
 
@@ -146,10 +163,7 @@ out:
 	return 1;
 }
 
-bool wlr_udev_init(struct wlr_drm_backend *backend)
-{
-	struct wlr_udev *udev = &backend->udev;
-
+bool wlr_udev_init(struct wl_display *display, struct wlr_udev *udev) {
 	udev->udev = udev_new();
 	if (!udev->udev) {
 		wlr_log(L_ERROR, "Failed to create udev context");
@@ -165,10 +179,12 @@ bool wlr_udev_init(struct wlr_drm_backend *backend)
 	udev_monitor_filter_add_match_subsystem_devtype(udev->mon, "drm", NULL);
 	udev_monitor_enable_receiving(udev->mon);
 
-	backend->event_src.udev = wl_event_loop_add_fd(backend->event_loop,
-			udev_monitor_get_fd(udev->mon), WL_EVENT_READABLE,
-			udev_event, backend);
-	if (!backend->event_src.udev) {
+	struct wl_event_loop *event_loop = wl_display_get_event_loop(display);
+	int fd = udev_monitor_get_fd(udev->mon);
+
+	udev->event = wl_event_loop_add_fd(event_loop, fd, WL_EVENT_READABLE,
+		udev_event, udev);
+	if (!udev->event) {
 		wlr_log(L_ERROR, "Failed to create udev event source");
 		goto error_mon;
 	}
@@ -184,11 +200,12 @@ error_udev:
 	return false;
 }
 
-void wlr_udev_free(struct wlr_udev *udev)
-
-{
-	if (!udev)
+void wlr_udev_free(struct wlr_udev *udev) {
+	if (!udev) {
 		return;
+	}
+
+	wl_event_source_remove(udev->event);
 
 	udev_monitor_unref(udev->mon);
 	udev_unref(udev->udev);