backend/drm: introduce wlr_drm_connector_state

Previously, we were copying wlr_output_state on the stack and
patching it up to be guaranteed to have a proper drmModeModeInfo
stored in it (and not a custom mode). Also, we had a bunch of
helpers deriving DRM-specific information from the generic
wlr_output_state.

Copying the wlr_output_state worked fine so far, but with output
layers we'll be getting a wl_list in there. An empty wl_list stores
two pointers to itself, copying it on the stack blindly results in
infinite loops in wl_list_for_each.

To fix this, rework our DRM backend to stop copying wlr_output_state,
instead add a new struct wlr_drm_connector_state which holds both
the wlr_output_state and additional DRM-specific information.

2 files changed, 10 insertions, 7 deletions

diff --git a/include/backend/drm/drm.h b/include/backend/drm/drm.h
index 87160ac6..69e563a9 100644
--- a/include/backend/drm/drm.h
+++ b/include/backend/drm/drm.h
@@ -104,6 +104,13 @@ struct wlr_drm_mode {
 	drmModeModeInfo drm_mode;
 };
 
+struct wlr_drm_connector_state {
+	const struct wlr_output_state *base;
+	bool modeset;
+	bool active;
+	drmModeModeInfo mode;
+};
+
 struct wlr_drm_connector {
 	struct wlr_output output; // only valid if status != DISCONNECTED
 
@@ -153,12 +160,6 @@ size_t drm_crtc_get_gamma_lut_size(struct wlr_drm_backend *drm,
 
 struct wlr_drm_fb *plane_get_next_fb(struct wlr_drm_plane *plane);
 
-bool drm_connector_state_is_modeset(const struct wlr_output_state *state);
-bool drm_connector_state_active(struct wlr_drm_connector *conn,
-	const struct wlr_output_state *state);
-void drm_connector_state_mode(struct wlr_drm_connector *conn,
-	const struct wlr_output_state *state, drmModeModeInfo *mode);
-
 #define wlr_drm_conn_log(conn, verb, fmt, ...) \
 	wlr_log(verb, "connector %s: " fmt, conn->name, ##__VA_ARGS__)
 #define wlr_drm_conn_log_errno(conn, verb, fmt, ...) \
diff --git a/include/backend/drm/iface.h b/include/backend/drm/iface.h
index 98f7e06c..d52bbd3d 100644
--- a/include/backend/drm/iface.h
+++ b/include/backend/drm/iface.h
@@ -9,12 +9,14 @@
 struct wlr_drm_backend;
 struct wlr_drm_connector;
 struct wlr_drm_crtc;
+struct wlr_drm_connector_state;
 
 // Used to provide atomic or legacy DRM functions
 struct wlr_drm_interface {
 	// Commit all pending changes on a CRTC.
 	bool (*crtc_commit)(struct wlr_drm_connector *conn,
-		const struct wlr_output_state *state, uint32_t flags, bool test_only);
+		const struct wlr_drm_connector_state *state, uint32_t flags,
+		bool test_only);
 };
 
 extern const struct wlr_drm_interface atomic_iface;