index: Add in save and load functionality

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

design/index.txt

@@ -30,6 +30,7 @@ Index: (lib/index.cpp)
 		const set<unsigned int> &operator[](string);
 	};
 
+	File << keys.size() << endl;
 	File << key << endl;
 	File << map[key].size() << int_0 << int_1 << ... << int_n << endl;
 

include/index.h

@@ -18,6 +18,8 @@ private:
 
 public:
 	Index(std::string);
+	void save();
+	void load();
 
 	void insert(std::string, unsigned int);
 	void remove(std::string);

lib/index.cpp

@@ -10,6 +10,48 @@ Index :: Index(std::string filepath)
 
 }
 
+void Index :: save()
+{
+	std::set<std::string>::iterator k_it;
+	std::set<unsigned int>::iterator u_it;
+
+	if (file.open(OPEN_WRITE) == false)
+		return;
+
+	file << keys.size();
+	for (k_it = keys.begin(); k_it != keys.end(); k_it++) {
+		file << *k_it << std::endl;
+		file << index[*k_it].size() << " ";
+
+		for (u_it = index[*k_it].begin(); u_it != index[*k_it].end(); u_it++)
+			file << *u_it << " ";
+
+		file << std::endl;
+	}
+
+	file.close();
+}
+
+void Index :: load()
+{
+	std::string key;
+	unsigned int num_keys, num_values, value;
+
+	if (file.open(OPEN_READ) == false)
+		return;
+
+	file >> num_keys;
+	for (unsigned int i = 0; i < num_keys; i++) {
+		file >> key >> num_values;
+		for (unsigned int j = 0; j < num_values; j++) {
+			file >> value;
+			insert(key, value);
+		}
+	}
+
+	file.close();
+}
+
 void Index :: insert(std::string key, unsigned int value)
 {
 	if (index.find(key) == index.end()) {

tests/index/index.cpp

@@ -113,10 +113,37 @@ void test_2()
 	print_index(index);
 }
 
+/*
+ * Save the database to disk
+ */
+void test_3()
+{
+	print("Test 3\n");
+	Index index("test.idx");
+
+	populate_index(index);
+	remove_values(index);
+	index.save();
+}
+
+/*
+ * Reload the database from disk
+ */
+void test_4()
+{
+	print("Test 4\n");
+	Index index("test.idx");
+
+	index.load();
+	print_index(index);
+}
+
 int main(int argc, char **argv)
 {
 	test_0();
 	test_1();
 	test_2();
+	test_3();
+	test_4();
 	return 0;
 }

tests/index/index.good

@@ -73,3 +73,32 @@ index[x] = {1 2 3 4 5 6 7 8 9}
 index[y] = {2 3 4 5 6 7 8 9}
 index[z] = {3 4 5 6 7 8 9}
 
+Test 3
+Test 4
+=== Printing index ===
+Found keys: a b c d e f g h i j l m n o p q r s t u w x y z
+index[a] = {0 1 2 3 4 5 6 7 8 9}
+index[b] = {1 2 3 4 5 6 7 8 9}
+index[c] = {2 3 4 5 6 7 8 9}
+index[d] = {3 4 5 6 7 8 9}
+index[e] = {4 5 6 7 8 9}
+index[f] = {5 6 7 8 9}
+index[g] = {6 7 8 9}
+index[h] = {7 8 9}
+index[i] = {8 9}
+index[j] = {9}
+index[l] = {0 1 2 3 4 5 6 7 8 9}
+index[m] = {1 2 3 4 5 6 7 8 9}
+index[n] = {2 3 4 5 6 7 8 9}
+index[o] = {3 4 5 6 7 8 9}
+index[p] = {4 5 6 7 8 9}
+index[q] = {5 6 7 8 9}
+index[r] = {6 7 8 9}
+index[s] = {7 8 9}
+index[t] = {8 9}
+index[u] = {9}
+index[w] = {0 1 2 3 4 5 6 7 8 9}
+index[x] = {1 2 3 4 5 6 7 8 9}
+index[y] = {2 3 4 5 6 7 8 9}
+index[z] = {3 4 5 6 7 8 9}
+