4 files changed, 27 insertions, 22 deletions

diff --git a/src/database/database-leveldb.cpp b/src/database/database-leveldb.cpp
index 73cd63f6d..39f4c8442 100644
--- a/src/database/database-leveldb.cpp
+++ b/src/database/database-leveldb.cpp
@@ -70,11 +70,11 @@ bool Database_LevelDB::saveBlock(const v3s16 &pos, const std::string &data)
 
 void Database_LevelDB::loadBlock(const v3s16 &pos, std::string *block)
 {
-	std::string datastr;
 	leveldb::Status status = m_database->Get(leveldb::ReadOptions(),
-		i64tos(getBlockAsInteger(pos)), &datastr);
+		i64tos(getBlockAsInteger(pos)), block);
 
-	*block = (status.ok()) ? datastr : "";
+	if (!status.ok())
+		block->clear();	
 }
 
 bool Database_LevelDB::deleteBlock(const v3s16 &pos)
@@ -131,7 +131,7 @@ void PlayerDatabaseLevelDB::savePlayer(RemotePlayer *player)
 	std::string (long) serialized_inventory
 	*/
 
-	std::ostringstream os;
+	std::ostringstream os(std::ios_base::binary);
 	writeU8(os, 1);
 
 	PlayerSAO *sao = player->getPlayerSAO();
@@ -142,7 +142,7 @@ void PlayerDatabaseLevelDB::savePlayer(RemotePlayer *player)
 	writeF32(os, sao->getRotation().Y);
 	writeU16(os, sao->getBreath());
 
-	StringMap stringvars = sao->getMeta().getStrings();
+	const auto &stringvars = sao->getMeta().getStrings();
 	writeU32(os, stringvars.size());
 	for (const auto &it : stringvars) {
 		os << serializeString16(it.first);
@@ -170,7 +170,7 @@ bool PlayerDatabaseLevelDB::loadPlayer(RemotePlayer *player, PlayerSAO *sao)
 		player->getName(), &raw);
 	if (!s.ok())
 		return false;
-	std::istringstream is(raw);
+	std::istringstream is(raw, std::ios_base::binary);
 
 	if (readU8(is) > 1)
 		return false;
@@ -230,7 +230,7 @@ bool AuthDatabaseLevelDB::getAuth(const std::string &name, AuthEntry &res)
 	leveldb::Status s = m_database->Get(leveldb::ReadOptions(), name, &raw);
 	if (!s.ok())
 		return false;
-	std::istringstream is(raw);
+	std::istringstream is(raw, std::ios_base::binary);
 
 	/*
 	u8 version = 1
@@ -262,7 +262,7 @@ bool AuthDatabaseLevelDB::getAuth(const std::string &name, AuthEntry &res)
 
 bool AuthDatabaseLevelDB::saveAuth(const AuthEntry &authEntry)
 {
-	std::ostringstream os;
+	std::ostringstream os(std::ios_base::binary);
 	writeU8(os, 1);
 	os << serializeString16(authEntry.password);
 
diff --git a/src/database/database-postgresql.cpp b/src/database/database-postgresql.cpp
index 29ecd4223..3469f4242 100644
--- a/src/database/database-postgresql.cpp
+++ b/src/database/database-postgresql.cpp
@@ -274,10 +274,10 @@ void MapDatabasePostgreSQL::loadBlock(const v3s16 &pos, std::string *block)
 	PGresult *results = execPrepared("read_block", ARRLEN(args), args,
 		argLen, argFmt, false);
 
-	*block = "";
-
 	if (PQntuples(results))
-		*block = std::string(PQgetvalue(results, 0, 0), PQgetlength(results, 0, 0));
+		block->assign(PQgetvalue(results, 0, 0), PQgetlength(results, 0, 0));
+	else
+		block->clear();
 
 	PQclear(results);
 }
@@ -496,6 +496,7 @@ void PlayerDatabasePostgreSQL::savePlayer(RemotePlayer *player)
 	execPrepared("remove_player_inventory_items", 1, rmvalues);
 
 	std::vector<const InventoryList*> inventory_lists = sao->getInventory()->getLists();
+	std::ostringstream oss;
 	for (u16 i = 0; i < inventory_lists.size(); i++) {
 		const InventoryList* list = inventory_lists[i];
 		const std::string &name = list->getName();
@@ -512,9 +513,10 @@ void PlayerDatabasePostgreSQL::savePlayer(RemotePlayer *player)
 		execPrepared("add_player_inventory", 5, inv_values);
 
 		for (u32 j = 0; j < list->getSize(); j++) {
-			std::ostringstream os;
-			list->getItem(j).serialize(os);
-			std::string itemStr = os.str(), slotId = itos(j);
+			oss.str("");
+			oss.clear();
+			list->getItem(j).serialize(oss);
+			std::string itemStr = oss.str(), slotId = itos(j);
 
 			const char* invitem_values[] = {
 				player->getName(),
diff --git a/src/database/database-redis.cpp b/src/database/database-redis.cpp
index 096ea504d..5ffff67b7 100644
--- a/src/database/database-redis.cpp
+++ b/src/database/database-redis.cpp
@@ -127,8 +127,7 @@ void Database_Redis::loadBlock(const v3s16 &pos, std::string *block)
 
 	switch (reply->type) {
 	case REDIS_REPLY_STRING: {
-		*block = std::string(reply->str, reply->len);
-		// std::string copies the memory so this won't cause any problems
+		block->assign(reply->str, reply->len);
 		freeReplyObject(reply);
 		return;
 	}
@@ -141,8 +140,7 @@ void Database_Redis::loadBlock(const v3s16 &pos, std::string *block)
 			"Redis command 'HGET %s %s' errored: ") + errstr);
 	}
 	case REDIS_REPLY_NIL: {
-		*block = "";
-		// block not found in database
+		block->clear();
 		freeReplyObject(reply);
 		return;
 	}
diff --git a/src/database/database-sqlite3.cpp b/src/database/database-sqlite3.cpp
index 4560743b9..898acc265 100644
--- a/src/database/database-sqlite3.cpp
+++ b/src/database/database-sqlite3.cpp
@@ -302,7 +302,10 @@ void MapDatabaseSQLite3::loadBlock(const v3s16 &pos, std::string *block)
 	const char *data = (const char *) sqlite3_column_blob(m_stmt_read, 0);
 	size_t len = sqlite3_column_bytes(m_stmt_read, 0);
 
-	*block = (data) ? std::string(data, len) : "";
+	if (data)
+		block->assign(data, len);
+	else
+		block->clear();
 
 	sqlite3_step(m_stmt_read);
 	// We should never get more than 1 row, so ok to reset
@@ -491,6 +494,7 @@ void PlayerDatabaseSQLite3::savePlayer(RemotePlayer *player)
 	sqlite3_reset(m_stmt_player_remove_inventory_items);
 
 	std::vector<const InventoryList*> inventory_lists = sao->getInventory()->getLists();
+	std::ostringstream oss;
 	for (u16 i = 0; i < inventory_lists.size(); i++) {
 		const InventoryList* list = inventory_lists[i];
 
@@ -503,9 +507,10 @@ void PlayerDatabaseSQLite3::savePlayer(RemotePlayer *player)
 		sqlite3_reset(m_stmt_player_add_inventory);
 
 		for (u32 j = 0; j < list->getSize(); j++) {
-			std::ostringstream os;
-			list->getItem(j).serialize(os);
-			std::string itemStr = os.str();
+			oss.str("");
+			oss.clear();
+			list->getItem(j).serialize(oss);
+			std::string itemStr = oss.str();
 
 			str_to_sqlite(m_stmt_player_add_inventory_items, 1, player->getName());
 			int_to_sqlite(m_stmt_player_add_inventory_items, 2, i);