Fix T52332: crash when duplicating sequencer strips.

Bug introduced in recent ID copying refactor.

This commit basically sanitizes seq strip copying behavior, by making
destination scene pointer mandatory (and source one a const one).
Nothing then prevents you from using same pointer as source and
destination!

1 files changed, 13 insertions, 10 deletions

diff --git a/source/blender/blenkernel/intern/sequencer.c b/source/blender/blenkernel/intern/sequencer.c
index a7991139b3f..76335f484cf 100644
--- a/source/blender/blenkernel/intern/sequencer.c
+++ b/source/blender/blenkernel/intern/sequencer.c
@@ -5371,9 +5371,8 @@ Sequence *BKE_sequencer_add_movie_strip(bContext *C, ListBase *seqbasep, SeqLoad
 	return seq;
 }
 
-static Sequence *seq_dupli(Scene *scene, Scene *scene_to, Sequence *seq, int dupe_flag, const int flag)
+static Sequence *seq_dupli(const Scene *scene, Scene *scene_to, Sequence *seq, int dupe_flag, const int flag)
 {
-	Scene *sce_audio = scene_to ? scene_to : scene;
 	Sequence *seqn = MEM_dupallocN(seq);
 
 	seq->tmp = seqn;
@@ -5416,7 +5415,7 @@ static Sequence *seq_dupli(Scene *scene, Scene *scene_to, Sequence *seq, int dup
 	else if (seq->type == SEQ_TYPE_SCENE) {
 		seqn->strip->stripdata = NULL;
 		if (seq->scene_sound)
-			seqn->scene_sound = BKE_sound_scene_add_scene_sound_defaults(sce_audio, seqn);
+			seqn->scene_sound = BKE_sound_scene_add_scene_sound_defaults(scene_to, seqn);
 	}
 	else if (seq->type == SEQ_TYPE_MOVIECLIP) {
 		/* avoid assert */
@@ -5433,7 +5432,7 @@ static Sequence *seq_dupli(Scene *scene, Scene *scene_to, Sequence *seq, int dup
 		seqn->strip->stripdata =
 		        MEM_dupallocN(seq->strip->stripdata);
 		if (seq->scene_sound)
-			seqn->scene_sound = BKE_sound_add_scene_sound_defaults(sce_audio, seqn);
+			seqn->scene_sound = BKE_sound_add_scene_sound_defaults(scene_to, seqn);
 
 		if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
 			id_us_plus((ID *)seqn->sound);
@@ -5457,11 +5456,15 @@ static Sequence *seq_dupli(Scene *scene, Scene *scene_to, Sequence *seq, int dup
 		BLI_assert(0);
 	}
 
-	if (dupe_flag & SEQ_DUPE_UNIQUE_NAME)
-		BKE_sequence_base_unique_name_recursive(&scene->ed->seqbase, seqn);
+	if (scene == scene_to) {
+		if (dupe_flag & SEQ_DUPE_UNIQUE_NAME) {
+			BKE_sequence_base_unique_name_recursive(&scene_to->ed->seqbase, seqn);
+		}
 
-	if (dupe_flag & SEQ_DUPE_ANIM)
-		BKE_sequencer_dupe_animdata(scene, seq->name + 2, seqn->name + 2);
+		if (dupe_flag & SEQ_DUPE_ANIM) {
+			BKE_sequencer_dupe_animdata(scene_to, seq->name + 2, seqn->name + 2);
+		}
+	}
 
 	return seqn;
 }
@@ -5488,7 +5491,7 @@ static void seq_new_fix_links_recursive(Sequence *seq)
 	}
 }
 
-Sequence *BKE_sequence_dupli_recursive(Scene *scene, Scene *scene_to, Sequence *seq, int dupe_flag)
+Sequence *BKE_sequence_dupli_recursive(const Scene *scene, Scene *scene_to, Sequence *seq, int dupe_flag)
 {
 	Sequence *seqn;
 
@@ -5522,7 +5525,7 @@ void BKE_sequence_base_dupli_recursive(
 	for (seq = seqbase->first; seq; seq = seq->next) {
 		seq->tmp = NULL;
 		if ((seq->flag & SELECT) || (dupe_flag & SEQ_DUPE_ALL)) {
-			seqn = seq_dupli((Scene *)scene, scene_to, seq, dupe_flag, flag);
+			seqn = seq_dupli(scene, scene_to, seq, dupe_flag, flag);
 			if (seqn) { /*should never fail */
 				if (dupe_flag & SEQ_DUPE_CONTEXT) {
 					seq->flag &= ~SEQ_ALLSEL;