Merge branch 'master' into blender2.8

2 files changed, 35 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_listbase.h b/source/blender/blenlib/BLI_listbase.h
index 4ec222c073e..5f57f46066f 100644
--- a/source/blender/blenlib/BLI_listbase.h
+++ b/source/blender/blenlib/BLI_listbase.h
@@ -67,6 +67,7 @@ void *BLI_poptail(ListBase *listbase) ATTR_NONNULL(1);
 void BLI_addhead(struct ListBase *listbase, void *vlink) ATTR_NONNULL(1);
 void BLI_insertlinkbefore(struct ListBase *listbase, void *vnextlink, void *vnewlink) ATTR_NONNULL(1);
 void BLI_insertlinkafter(struct ListBase *listbase, void *vprevlink, void *vnewlink) ATTR_NONNULL(1);
+void BLI_insertlinkreplace(ListBase *listbase, void *v_l_src, void *v_l_dst) ATTR_NONNULL(1, 2, 3);
 void BLI_listbase_sort(struct ListBase *listbase, int (*cmp)(const void *, const void *)) ATTR_NONNULL(1, 2);
 void BLI_listbase_sort_r(ListBase *listbase, int (*cmp)(void *, const void *, const void *), void *thunk) ATTR_NONNULL(1, 2);
 bool BLI_listbase_link_move(ListBase *listbase, void *vlink, int step) ATTR_NONNULL();
diff --git a/source/blender/blenlib/intern/listbase.c b/source/blender/blenlib/intern/listbase.c
index 3bf0dfa09fa..abc4a773328 100644
--- a/source/blender/blenlib/intern/listbase.c
+++ b/source/blender/blenlib/intern/listbase.c
@@ -370,6 +370,40 @@ void BLI_insertlinkbefore(ListBase *listbase, void *vnextlink, void *vnewlink)
 	}
 }
 
+
+/**
+ * Insert a link in place of another, without changing it's position in the list.
+ *
+ * Puts `vnewlink` in the position of `vreplacelink`, removing `vreplacelink`.
+ * - `vreplacelink` *must* be in the list.
+ * - `vnewlink` *must not* be in the list.
+ */
+void BLI_insertlinkreplace(ListBase *listbase, void *vreplacelink, void *vnewlink)
+{
+	Link *l_old = vreplacelink;
+	Link *l_new = vnewlink;
+
+	/* update adjacent links */
+	if (l_old->next != NULL) {
+		l_old->next->prev = l_new;
+	}
+	if (l_old->prev != NULL) {
+		l_old->prev->next = l_new;
+	}
+
+	/* set direct links */
+	l_new->next = l_old->next;
+	l_new->prev = l_old->prev;
+
+	 /* update list */
+	if (listbase->first == l_old) {
+		listbase->first = l_new;
+	}
+	if (listbase->last == l_old) {
+		listbase->last = l_new;
+	}
+}
+
 /**
  * Reinsert \a vlink relative to its current position but offset by \a step. Doesn't move
  * item if new position would exceed list (could optionally move to head/tail).