rbtree: Update maximum node in LIFO order

The test sptests/sp35 showed a NULL pointer access due to an invalid
maximum node field (e.g. a tree with one element and NULL as the maximum
node).

2 files changed, 107 insertions, 9 deletions

diff --git a/testsuites/sptests/sprbtree01/init.c b/testsuites/sptests/sprbtree01/init.c
index 956271b325..2c62d12b6d 100644
--- a/testsuites/sptests/sprbtree01/init.c
+++ b/testsuites/sptests/sprbtree01/init.c
@@ -19,11 +19,13 @@ const char rtems_test_name[] = "SPRBTREE 1";
 /* forward declarations to avoid warnings */
 rtems_task Init(rtems_task_argument argument);
 
-int numbers[20] = {
-52, 99, 0, 85, 43, 44, 10, 60, 50, 19, 8, 68, 48, 57, 17, 67, 90, 12, 77, 71};
+static const int numbers[20] = {
+  52, 99, 0, 85, 43, 44, 10, 60, 50, 19, 8, 68, 48, 57, 17, 67, 90, 12, 77, 71
+};
 
-int numbers_sorted[20] = {
-  0, 8, 10, 12, 17, 19, 43, 44, 48, 50, 52, 57, 60, 67, 68, 71, 77, 85, 90, 99};
+static const int numbers_sorted[20] = {
+  0, 8, 10, 12, 17, 19, 43, 44, 48, 50, 52, 57, 60, 67, 68, 71, 77, 85, 90, 99
+};
 
 typedef struct {
   int              id;
@@ -121,11 +123,104 @@ static int rb_assert ( rtems_rbtree_node *root )
   }
 }
 
+static test_node some_nodes[] = {
+  { .key = 1 },
+  { .key = 1 },
+  { .key = 1 },
+  { .key = 2 },
+  { .key = 2 },
+  { .key = 2 }
+};
+
+static void min_max_insert(
+  rtems_rbtree_control *tree,
+  rtems_rbtree_node    *node,
+  rtems_rbtree_node    *min,
+  rtems_rbtree_node    *max
+)
+{
+  rb_insert_multi( tree, node );
+  rtems_test_assert( rb_assert( tree->root ) != -1 );
+  rtems_test_assert( tree->first[ 0 ] == min );
+  rtems_test_assert( tree->first[ 1 ] == max );
+}
+
+static void min_max_extract(
+  rtems_rbtree_control *tree,
+  rtems_rbtree_node    *node,
+  rtems_rbtree_node    *min,
+  rtems_rbtree_node    *max
+)
+{
+  rtems_rbtree_extract( tree, node );
+  rtems_test_assert( rb_assert( tree->root ) != -1 );
+  rtems_test_assert( tree->first[ 0 ] == min );
+  rtems_test_assert( tree->first[ 1 ] == max );
+}
+
+static void test_rbtree_min_max(void)
+{
+  rtems_rbtree_control  tree;
+  rtems_rbtree_node    *node;
+  rtems_rbtree_node    *min;
+  rtems_rbtree_node    *max;
+
+  puts( "INIT - Verify min/max node updates" );
+
+  rtems_rbtree_initialize_empty( &tree );
+  rtems_test_assert( rb_assert( tree.root ) == 1 );
+
+  node = &some_nodes[ 0 ].Node;
+  min = node;
+  max = node;
+  min_max_insert( &tree, node, min, max );
 
+  node = &some_nodes[ 1 ].Node;
+  max = node;
+  min_max_insert( &tree, node, min, max );
 
-rtems_task Init(
-    rtems_task_argument ignored
-    )
+  node = &some_nodes[ 2 ].Node;
+  max = node;
+  min_max_insert( &tree, node, min, max );
+
+  node = &some_nodes[ 3 ].Node;
+  max = node;
+  min_max_insert( &tree, node, min, max );
+
+  node = &some_nodes[ 4 ].Node;
+  max = node;
+  min_max_insert( &tree, node, min, max );
+
+  node = &some_nodes[ 5 ].Node;
+  max = node;
+  min_max_insert( &tree, node, min, max );
+
+  node = &some_nodes[ 1 ].Node;
+  min_max_extract( &tree, node, min, max );
+
+  node = &some_nodes[ 4 ].Node;
+  min_max_extract( &tree, node, min, max );
+
+  node = &some_nodes[ 0 ].Node;
+  min = &some_nodes[ 2 ].Node;
+  min_max_extract( &tree, node, min, max );
+
+  node = &some_nodes[ 5 ].Node;
+  max = &some_nodes[ 3 ].Node;
+  min_max_extract( &tree, node, min, max );
+
+  node = &some_nodes[ 2 ].Node;
+  min = &some_nodes[ 3 ].Node;
+  min_max_extract( &tree, node, min, max );
+
+  node = &some_nodes[ 3 ].Node;
+  min = NULL;
+  max = NULL;
+  min_max_extract( &tree, node, min, max );
+  rtems_test_assert( rtems_rbtree_is_empty( &tree ) );
+}
+
+rtems_task Init( rtems_task_argument ignored )
 {
   rtems_rbtree_control  rbtree1;
   rtems_rbtree_node    *p;
@@ -682,6 +777,8 @@ rtems_task Init(
     rtems_test_exit(0);
   }
 
+  test_rbtree_min_max();
+
   TEST_END();
   rtems_test_exit(0);
 }
diff --git a/testsuites/sptests/sprbtree01/sprbtree01.scn b/testsuites/sptests/sprbtree01/sprbtree01.scn
index 0bf200717b..0d37566770 100644
--- a/testsuites/sptests/sprbtree01/sprbtree01.scn
+++ b/testsuites/sptests/sprbtree01/sprbtree01.scn
@@ -1,4 +1,4 @@
-*** TEST OF RTEMS RBTREE API ***
+*** BEGIN OF TEST SPRBTREE 1 ***
 Init - Initialize rbtree empty
 INIT - Verify rtems_rbtree_insert with two nodes
 INIT - Verify rtems_rbtree_insert with the same value twice
@@ -31,4 +31,5 @@ INIT - Removing 100 nodes
 INIT - Verify rtems_rbtree_insert with 100 nodes value [99,0]
 INIT - Verify rtems_rbtree_find in a duplicate tree
 INIT - Removing 100 nodes
-*** END OF RTEMS RBTREE API TEST ***
+INIT - Verify min/max node updates
+*** END OF TEST SPRBTREE 1 ***