[PATCH weston v5 09/11] drm: Don't hang onto the backend config object post-backend_init

[Bryce Harrington]

The drm backend was copying most everything out of the config object
already, but now also copy the use_current_mode parameter and the
config_output function pointer, so that there are no remaining
references to the config object passed into backend_init().

By decoupling the config struct to the backend, if in the future if the
structure definition changes in non-backwards compatible ways, then any
version compatibility adaptation will be limited to just the
backend_init() routine.

Signed-off-by: Bryce Harrington <bryce at osg.samsung.com>
---
 src/compositor-drm.c | 24 +++++++++++++++---------
 src/compositor-drm.h |  3 ++-
 src/main.c           | 18 ++++++++----------
 3 files changed, 25 insertions(+), 20 deletions(-)

diff --git a/src/compositor-drm.c b/src/compositor-drm.c
index 38296e2..722cc6a 100644
--- a/src/compositor-drm.c
+++ b/src/compositor-drm.c
@@ -121,7 +121,17 @@ struct drm_backend {
 	int32_t cursor_width;
 	int32_t cursor_height;
 
-	struct weston_drm_backend_config *config;
+        /** Callback used to configure the outputs.
+	 *
+         * This function will be called by the backend when a new DRM
+         * output needs to be configured.
+         */
+        enum weston_drm_backend_output_mode
+	(*configure_output)(struct weston_compositor *compositor,
+			    bool use_current_mode,
+			    const char *name,
+			    struct weston_drm_backend_output_config *output_config);
+	bool use_current_mode;
 };
 
 struct drm_mode {
@@ -2311,8 +2321,8 @@ create_output_for_connector(struct drm_backend *b,
 	output->base.serial_number = "unknown";
 	wl_list_init(&output->base.mode_list);
 
-	mode = b->config->configure_output(b->compositor, b->config,
-					   output->base.name, &config);
+	mode = b->configure_output(b->compositor, b->use_current_mode,
+				   output->base.name, &config);
 	if (parse_gbm_format(config.gbm_format, b->gbm_format, &output->gbm_format) == -1)
 		output->gbm_format = b->gbm_format;
 
@@ -2699,11 +2709,6 @@ drm_destroy(struct weston_compositor *ec)
 	weston_launcher_destroy(ec->launcher);
 
 	close(b->drm.fd);
-
-	free(b->config->gbm_format);
-	free(b->config->seat_id);
-	free(b->config);
-
 	free(b);
 }
 
@@ -3054,7 +3059,8 @@ drm_backend_create(struct weston_compositor *compositor,
 	b->sprites_are_broken = 1;
 	b->compositor = compositor;
 	b->use_pixman = config->use_pixman;
-	b->config = config;
+	b->configure_output = config->configure_output;
+	b->use_current_mode = config->use_current_mode;
 
 	if (parse_gbm_format(config->gbm_format, GBM_FORMAT_XRGB8888, &b->gbm_format) < 0)
 		goto err_compositor;
diff --git a/src/compositor-drm.h b/src/compositor-drm.h
index 3b54ca5..7e0913a 100644
--- a/src/compositor-drm.h
+++ b/src/compositor-drm.h
@@ -112,9 +112,10 @@ struct weston_drm_backend_config {
 	 */
 	enum weston_drm_backend_output_mode
 		(*configure_output)(struct weston_compositor *compositor,
-				    struct weston_drm_backend_config *backend_config,
+				    bool use_current_mode,
 				    const char *name,
 				    struct weston_drm_backend_output_config *output_config);
+	bool use_current_mode;
 };
 
 #ifdef  __cplusplus
diff --git a/src/main.c b/src/main.c
index f652701..c499fd0 100644
--- a/src/main.c
+++ b/src/main.c
@@ -683,11 +683,10 @@ struct drm_config {
 
 static enum weston_drm_backend_output_mode
 drm_configure_output(struct weston_compositor *c,
-		     struct weston_drm_backend_config *backend_config,
+		     bool use_current_mode,
 		     const char *name,
 		     struct weston_drm_backend_output_config *config)
 {
-	struct drm_config *drm_config = (struct drm_config *)backend_config;
 	struct weston_config *wc = weston_compositor_get_user_data(c);
 	struct weston_config_section *section;
 	char *s;
@@ -702,7 +701,7 @@ drm_configure_output(struct weston_compositor *c,
 		return WESTON_DRM_BACKEND_OUTPUT_OFF;
 	}
 
-	if (drm_config->use_current_mode || strcmp(s, "current") == 0) {
+	if (use_current_mode || strcmp(s, "current") == 0) {
 		mode = WESTON_DRM_BACKEND_OUTPUT_CURRENT;
 	} else if (strcmp(s, "preferred") != 0) {
 		config->modeline = s;
@@ -756,13 +755,12 @@ load_drm_backend(struct weston_compositor *c, const char *backend,
 	config->base.base.struct_size = sizeof(struct weston_drm_backend_config);
 	config->base.configure_output = drm_configure_output;
 
-	if (load_backend_new(c, backend,
-			     (struct weston_backend_config *)(&config->base)) < 0) {
-		ret = -1;
-		free(config->base.gbm_format);
-		free(config->base.seat_id);
-		free(config);
-	}
+	ret = load_backend_new(c, backend,
+			       (struct weston_backend_config *)(&config->base));
+
+	free(config->base.gbm_format);
+	free(config->base.seat_id);
+	free(config);
 
 	return ret;
 }
-- 
1.9.1