Add dbiIndexSetPruneSet helper

Also make pruning from an empty set non-fatal.

(cherry picked from commit 8d54160ecea351e5b5ef055ceb1378cb6adaf8e4)

2 files changed, 20 insertions, 1 deletions

diff --git a/lib/backend/dbiset.c b/lib/backend/dbiset.c
index 9ad143f28..649ea8866 100644
--- a/lib/backend/dbiset.c
+++ b/lib/backend/dbiset.c
@@ -126,7 +126,9 @@ int dbiIndexSetPrune(dbiIndexSet set, dbiIndexItem recs,
     unsigned int numCopied = 0;
     size_t recsize = sizeof(*recs);
 
-    assert(set->count > 0);
+    if (num == 0 || nrecs == 0)
+	return 1;
+
     if (nrecs > 1 && !sorted)
 	qsort(recs, nrecs, recsize, hdrNumCmp);
 
@@ -143,6 +145,13 @@ int dbiIndexSetPrune(dbiIndexSet set, dbiIndexItem recs,
     return (numCopied == num);
 }
 
+int dbiIndexSetPruneSet(dbiIndexSet set, dbiIndexSet oset, int sortset)
+{
+    if (oset == NULL)
+	return 1;
+    return dbiIndexSetPrune(set, oset->recs, oset->count, sortset);
+}
+
 unsigned int dbiIndexSetCount(dbiIndexSet set)
 {
     return (set != NULL) ? set->count : 0;
diff --git a/lib/backend/dbiset.h b/lib/backend/dbiset.h
index 88182d24a..506375865 100644
--- a/lib/backend/dbiset.h
+++ b/lib/backend/dbiset.h
@@ -76,6 +76,16 @@ RPM_GNUC_INTERNAL
 int dbiIndexSetPrune(dbiIndexSet set, dbiIndexItem recs,
 		     unsigned int nrecs, int sorted);
 
+/**
+ * Remove an index set from another.
+ * @param set          set of index database items
+ * @param oset         set of entries that should be removed
+ * @param sorted       oset is already sorted?
+ * @return             0 success, 1 failure (no items found)
+ */
+RPM_GNUC_INTERNAL
+int dbiIndexSetPruneSet(dbiIndexSet set, dbiIndexSet oset, int sorted);
+
 /* Count items in index database set. */
 RPM_GNUC_INTERNAL
 unsigned int dbiIndexSetCount(dbiIndexSet set);