database: Add a function for clearing databases

Signed-off-by: Anna Schumaker <schumaker.anna@gmail.com>

design/database.txt

@@ -88,6 +88,11 @@ Database: (lib/database.cpp)
 	void Database :: save();
 		Saves the database to disk.
 
+	void Database :: clear();
+		This function exists only if CONFIG_DEBUG is enabled.
+		Clear the database contents in-memory, but do NOT write
+		to disk.
+
 	void Database :: print()
 		This function exists only If CONFIG_DEBUG is enabled.
 		Following a similar format for writing to disk, print the

include/database.h

@@ -42,6 +42,7 @@ public:
 	void save();
 	void load();
 #ifdef CONFIG_DEBUG
+	void clear();
 	void print();
 #endif /* CONFIG_DEBUG */
 

include/database.hpp

@@ -55,6 +55,14 @@ void Database<T> :: load()
 	file.close();
 }
 
+#ifdef CONFIG_DEBUG
+template <class T>
+void Database<T> :: clear()
+{
+	db.clear();
+	_size = 0;
+}
+
 template <class T>
 void Database<T> :: print()
 {
@@ -68,6 +76,7 @@ void Database<T> :: print()
 		:: print("\n");
 	}
 }
+#endif /* CONFIG_DEBUG */
 
 template <class T>
 unsigned int Database<T> :: insert(T val)

tests/database/database.cpp

@@ -149,6 +149,20 @@ void test_5()
 	db.print();
 }
 
+/*
+ * Test the database's clear() function
+ */
+void test_6()
+{
+	print("\nTest 6\n");
+	Database<DBTest> db("", DB_NORMAL);
+	for (unsigned int i = 0; i < 10; i++)
+		db.insert(DBTest(i));
+	db.print();
+	db.clear();
+	db.print();
+}
+
 int main(int argc, char **argv)
 {
 	test_0();
@@ -157,6 +171,7 @@ int main(int argc, char **argv)
 	test_3();
 	test_4();
 	test_5();
+	test_6();
 
 	return 0;
 }

tests/database/database.good

@@ -300052,3 +300052,19 @@ db[6] = 6
 db[7] = 7
 db[8] = 8
 db[9] = 9
+
+Test 6
+Database size: 10
+Valid rows: 10
+db[0] = 0
+db[1] = 1
+db[2] = 2
+db[3] = 3
+db[4] = 4
+db[5] = 5
+db[6] = 6
+db[7] = 7
+db[8] = 8
+db[9] = 9
+Database size: 0
+Valid rows: 0