list_delete_node function & tests

diff --git a/source/list/list.c b/source/list/list.c
index b2a0e92bbf84aa6735e08b9163d6746f7bcf2237..52ade37b8f46865b7a9418d12c3a9ffca1f3d650 100644 (file)
--- a/source/list/list.c
+++ b/source/list/list.c
@@ -203,6 +203,28 @@ list_node_t* list_delete( list_t* list, size_t index)
     return node;
 }
 
+void list_delete_node(list_t* list, list_node_t* node)
+{
+    if (NULL != list && NULL != node)
+    {
+        /* not using list_prev so node not found case can be handled properly */
+        list_node_t* prev = NULL;
+        list_node_t* edon = list->head;
+        while(NULL != edon && edon != node)
+        {
+            prev = edon;
+            edon = edon->next;
+        }
+        if( NULL != edon)
+        {
+            if(NULL != prev) prev->next = node->next;
+            if(list->head == node) list->head = node->next;
+            if(list->tail == node) list->tail = prev;
+            node->next = NULL;
+        } /* else node not found, do nothing. */
+    }
+}
+
 void list_clear(list_t* list)
 {
     if (NULL != list->head)

diff --git a/source/list/list.h b/source/list/list.h
index 3fc787ff6b8ed8e654788e67aa4f4a66ecab5ae8..bd8d08638e22b70149c19ecccd581babcc880188 100644 (file)
--- a/source/list/list.h
+++ b/source/list/list.h
@@ -184,6 +184,20 @@ list_node_t* list_insert( list_t* list, size_t index, void* contents);
  **/
 list_node_t* list_delete(list_t* list, size_t index);
 
+/**
+ * @brief Delete a node from the supplied list.
+ *
+ * This function differs from the above list_delete in that it is given a 
+ * pointer to a node to be deleted instead of an index.
+ * //TODO: verify node->next should be set to NULL following successful deletion
+ * //TODO: verify node->next should not be touched if node not present in list
+ * //TODO: verify node should not be freed following deletion
+ *
+ * @param list          The list to operate on.
+ * @param node          A pointer to the node to delete.
+ */
+void list_delete_node(list_t* list, list_node_t* node);
+
 /**
  * @brief Deletes all elements in the provided list
  *

diff --git a/tests/test_list.c b/tests/test_list.c
index d6168650c74a38d4efb18630c48f354a47cf3301..2347e288031d091e38364ec810fb55f751ca22d6 100644 (file)
--- a/tests/test_list.c
+++ b/tests/test_list.c
@@ -468,6 +468,113 @@ TEST_SUITE(List) {
         mem_release(list);
     }
 
+    //-------------------------------------------------------------------------
+    // Test list_delete_node function
+    //-------------------------------------------------------------------------
+    TEST(Verify_delete_node_does_nothing_if_list_is_empty)
+    {
+        list_t list = { NULL, NULL };
+        list_node_t bogus = { NULL, NULL };
+        list_delete_node(&list, NULL);
+        CHECK( NULL == list.head);
+        CHECK( NULL == list.tail);
+        list_delete_node(&list, &bogus);
+        CHECK( NULL == list.head);
+        CHECK( NULL == list.tail);
+    }
+
+    TEST(Verify_delete_node_does_nothing_if_given_node_not_in_list)
+    {
+        list_node_t node3 = { NULL, NULL };
+        list_node_t node2 = { NULL, &node3 };
+        list_node_t node1 = { NULL, &node2 };
+        list_t list = { &node1, &node3 };
+        list_node_t bogus = { NULL, &node2 };
+        list_delete_node(&list, &bogus);
+        CHECK( &node2 == bogus.next );
+        CHECK( &node1 == list.head );
+        CHECK( &node2 == node1.next );
+        CHECK( &node3 == node2.next );
+        CHECK( NULL == node3.next );
+        CHECK( &node3 == list.tail );
+    }
+
+    TEST(Verify_delete_node_deletes_the_head_node_of_a_list_of_length_1)
+    {
+        list_node_t node1 = { NULL, NULL };
+        list_t list = { &node1, &node1 };
+        list_delete_node(&list, &node1);
+        CHECK( NULL == node1.next );
+        CHECK( NULL == list.head );
+        CHECK( NULL == list.tail );
+    }
+
+    TEST(Verify_delete_node_deletes_the_first_element_of_a_list_of_length_2)
+    {
+        list_node_t node2 = { NULL, NULL };
+        list_node_t node1 = { NULL, &node2 };
+        list_t list = { &node1, &node2 };
+        list_delete_node(&list, &node1);
+        CHECK( NULL == node1.next );
+        CHECK( &node2 == list.head );
+        CHECK( NULL == node2.next );
+        CHECK( &node2 == list.tail );
+    }
+
+    TEST(Verify_delete_node_deletes_the_second_element_of_a_list_of_length_2)
+    {
+        list_node_t node2 = { NULL, NULL };
+        list_node_t node1 = { NULL, &node2 };
+        list_t list = { &node1, &node2 };
+        list_delete_node(&list, &node2);
+        CHECK( NULL == node2.next );
+        CHECK( &node1 == list.head );
+        CHECK( NULL == node1.next );
+        CHECK( &node1 == list.tail );
+    }
+
+    TEST(Verify_delete_node_deletes_the_first_element_of_a_list_of_length_3)
+    {
+        list_node_t node3 = { NULL, NULL };
+        list_node_t node2 = { NULL, &node3 };
+        list_node_t node1 = { NULL, &node2 };
+        list_t list = { &node1, &node3 };
+        list_delete_node(&list, &node1);
+        CHECK( NULL == node1.next );
+        CHECK( &node2 == list.head );
+        CHECK( &node3 == node2.next );
+        CHECK( NULL == node3.next );
+        CHECK( &node3 == list.tail );
+    }
+
+    TEST(Verify_delete_node_deletes_the_second_element_of_a_list_of_length_3)
+    {
+        list_node_t node3 = { NULL, NULL };
+        list_node_t node2 = { NULL, &node3 };
+        list_node_t node1 = { NULL, &node2 };
+        list_t list = { &node1, &node3 };
+        list_delete_node(&list, &node2);
+        CHECK( NULL == node2.next );
+        CHECK( &node1 == list.head );
+        CHECK( &node3 == node1.next );
+        CHECK( NULL == node3.next );
+        CHECK( &node3 == list.tail );
+    }
+
+    TEST(Verify_delete_node_deletes_the_third_element_of_a_list_of_length_3)
+    {
+        list_node_t node3 = { NULL, NULL };
+        list_node_t node2 = { NULL, &node3 };
+        list_node_t node1 = { NULL, &node2 };
+        list_t list = { &node1, &node3 };
+        list_delete_node(&list, &node3);
+        CHECK( NULL == node3.next );
+        CHECK( &node1 == list.head );
+        CHECK( &node2 == node1.next );
+        CHECK( NULL == node2.next );
+        CHECK( &node2 == list.tail );
+    }
+
     //-------------------------------------------------------------------------
     // Test list_clear function
     //-------------------------------------------------------------------------