database: Implement quick removal of items

Items will be marked "invalid" rather than directly removed from the
database.  This make it easier, since I won't need to reassign IDs to
every database item after the removed one.

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

include/database.h

@@ -29,6 +29,7 @@ public:
 	~Database();
 
 	unsigned int insert(T);
+	void remove(unsigned int);
 	unsigned int size();
 	unsigned int num_rows();
 

include/database.hpp

@@ -27,6 +27,13 @@ unsigned int Database<T> :: insert(T val)
 	return db.size() - 1;
 }
 
+template <class T>
+void Database<T> :: remove(unsigned int id)
+{
+	db[id].valid = false;
+	_size--;
+}
+
 template <class T>
 unsigned int Database<T> :: size()
 {

tests/database/database.cpp

@@ -30,14 +30,18 @@ void print_db(Database<DBTest> &db)
 
 void test_insertion(Database<DBTest> &db)
 {
-	for (unsigned int i = 1; i <= 10; i++)
+	for (unsigned int i = 1; i <= 1000; i++)
 		db.insert(DBTest(i));
-
 	print_db(db);
 }
 
 void test_deletion(Database<DBTest> &db)
 {
+	for (unsigned int i = db.first(); i < db.num_rows(); i = db.next(i)) {
+		db.remove(i);
+		i = db.next(i);
+	}
+	print_db(db);
 }
 
 int main(int argc, char **argv)
@@ -46,6 +50,7 @@ int main(int argc, char **argv)
 
 	test_insertion(db);
 	test_deletion(db);
+	test_deletion(db);
 
 	return 0;
 }