From d0bcdff5cee888d5c02273508ade987dba601b14 Mon Sep 17 00:00:00 2001
From: Desour <ds.desour@proton.me>
Date: Fri, 3 Mar 2023 14:53:37 +0100
Subject: [PATCH] Use unique_ptrs for leveldb db and iterators

---
 src/database/database-leveldb.cpp | 36 +++++++++++--------------------
 src/database/database-leveldb.h   | 13 +++++------
 2 files changed, 19 insertions(+), 30 deletions(-)

diff --git a/src/database/database-leveldb.cpp b/src/database/database-leveldb.cpp
index 6e59daab3..80493d5f2 100644
--- a/src/database/database-leveldb.cpp
+++ b/src/database/database-leveldb.cpp
@@ -45,14 +45,11 @@ Database_LevelDB::Database_LevelDB(const std::string &savedir)
 {
 	leveldb::Options options;
 	options.create_if_missing = true;
+	leveldb::DB *db;
 	leveldb::Status status = leveldb::DB::Open(options,
-		savedir + DIR_DELIM + "map.db", &m_database);
+		savedir + DIR_DELIM + "map.db", &db);
 	ENSURE_STATUS_OK(status);
-}
-
-Database_LevelDB::~Database_LevelDB()
-{
-	delete m_database;
+	m_database.reset(db);
 }
 
 bool Database_LevelDB::saveBlock(const v3s16 &pos, const std::string &data)
@@ -92,26 +89,22 @@ bool Database_LevelDB::deleteBlock(const v3s16 &pos)
 
 void Database_LevelDB::listAllLoadableBlocks(std::vector<v3s16> &dst)
 {
-	leveldb::Iterator* it = m_database->NewIterator(leveldb::ReadOptions());
+	std::unique_ptr<leveldb::Iterator> it(m_database->NewIterator(leveldb::ReadOptions()));
 	for (it->SeekToFirst(); it->Valid(); it->Next()) {
 		dst.push_back(getIntegerAsBlock(stoi64(it->key().ToString())));
 	}
 	ENSURE_STATUS_OK(it->status());  // Check for any errors found during the scan
-	delete it;
 }
 
 PlayerDatabaseLevelDB::PlayerDatabaseLevelDB(const std::string &savedir)
 {
 	leveldb::Options options;
 	options.create_if_missing = true;
+	leveldb::DB *db;
 	leveldb::Status status = leveldb::DB::Open(options,
-		savedir + DIR_DELIM + "players.db", &m_database);
+		savedir + DIR_DELIM + "players.db", &db);
 	ENSURE_STATUS_OK(status);
-}
-
-PlayerDatabaseLevelDB::~PlayerDatabaseLevelDB()
-{
-	delete m_database;
+	m_database.reset(db);
 }
 
 void PlayerDatabaseLevelDB::savePlayer(RemotePlayer *player)
@@ -202,26 +195,22 @@ bool PlayerDatabaseLevelDB::loadPlayer(RemotePlayer *player, PlayerSAO *sao)
 
 void PlayerDatabaseLevelDB::listPlayers(std::vector<std::string> &res)
 {
-	leveldb::Iterator* it = m_database->NewIterator(leveldb::ReadOptions());
+	std::unique_ptr<leveldb::Iterator> it(m_database->NewIterator(leveldb::ReadOptions()));
 	res.clear();
 	for (it->SeekToFirst(); it->Valid(); it->Next()) {
 		res.push_back(it->key().ToString());
 	}
-	delete it;
 }
 
 AuthDatabaseLevelDB::AuthDatabaseLevelDB(const std::string &savedir)
 {
 	leveldb::Options options;
 	options.create_if_missing = true;
+	leveldb::DB *db;
 	leveldb::Status status = leveldb::DB::Open(options,
-		savedir + DIR_DELIM + "auth.db", &m_database);
+		savedir + DIR_DELIM + "auth.db", &db);
 	ENSURE_STATUS_OK(status);
-}
-
-AuthDatabaseLevelDB::~AuthDatabaseLevelDB()
-{
-	delete m_database;
+	m_database.reset(db);
 }
 
 bool AuthDatabaseLevelDB::getAuth(const std::string &name, AuthEntry &res)
@@ -293,12 +282,11 @@ bool AuthDatabaseLevelDB::deleteAuth(const std::string &name)
 
 void AuthDatabaseLevelDB::listNames(std::vector<std::string> &res)
 {
-	leveldb::Iterator* it = m_database->NewIterator(leveldb::ReadOptions());
+	std::unique_ptr<leveldb::Iterator> it(m_database->NewIterator(leveldb::ReadOptions()));
 	res.clear();
 	for (it->SeekToFirst(); it->Valid(); it->Next()) {
 		res.emplace_back(it->key().ToString());
 	}
-	delete it;
 }
 
 void AuthDatabaseLevelDB::reload()
diff --git a/src/database/database-leveldb.h b/src/database/database-leveldb.h
index 61def1256..812752a67 100644
--- a/src/database/database-leveldb.h
+++ b/src/database/database-leveldb.h
@@ -23,6 +23,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 #if USE_LEVELDB
 
+#include <memory>
 #include <string>
 #include "database.h"
 #include "leveldb/db.h"
@@ -31,7 +32,7 @@ class Database_LevelDB : public MapDatabase
 {
 public:
 	Database_LevelDB(const std::string &savedir);
-	~Database_LevelDB();
+	~Database_LevelDB() = default;
 
 	bool saveBlock(const v3s16 &pos, const std::string &data);
 	void loadBlock(const v3s16 &pos, std::string *block);
@@ -42,14 +43,14 @@ public:
 	void endSave() {}
 
 private:
-	leveldb::DB *m_database;
+	std::unique_ptr<leveldb::DB> m_database;
 };
 
 class PlayerDatabaseLevelDB : public PlayerDatabase
 {
 public:
 	PlayerDatabaseLevelDB(const std::string &savedir);
-	~PlayerDatabaseLevelDB();
+	~PlayerDatabaseLevelDB() = default;
 
 	void savePlayer(RemotePlayer *player);
 	bool loadPlayer(RemotePlayer *player, PlayerSAO *sao);
@@ -57,14 +58,14 @@ public:
 	void listPlayers(std::vector<std::string> &res);
 
 private:
-	leveldb::DB *m_database;
+	std::unique_ptr<leveldb::DB> m_database;
 };
 
 class AuthDatabaseLevelDB : public AuthDatabase
 {
 public:
 	AuthDatabaseLevelDB(const std::string &savedir);
-	virtual ~AuthDatabaseLevelDB();
+	virtual ~AuthDatabaseLevelDB() = default;
 
 	virtual bool getAuth(const std::string &name, AuthEntry &res);
 	virtual bool saveAuth(const AuthEntry &authEntry);
@@ -74,7 +75,7 @@ public:
 	virtual void reload();
 
 private:
-	leveldb::DB *m_database;
+	std::unique_ptr<leveldb::DB> m_database;
 };
 
 #endif // USE_LEVELDB