Avoid duplication of mod metadata in memory (#12562)

Co-authored-by: sfan5 <sfan5@live.de>

7 files changed, 153 insertions, 8 deletions

diff --git a/src/database/database-dummy.cpp b/src/database/database-dummy.cpp
index a44762d8a..ee88c6684 100644
--- a/src/database/database-dummy.cpp
+++ b/src/database/database-dummy.cpp
@@ -92,6 +92,32 @@ bool Database_Dummy::getModEntries(const std::string &modname, StringMap *storag
 	return true;
 }
 
+bool Database_Dummy::getModEntry(const std::string &modname,
+	const std::string &key, std::string *value)
+{
+	auto mod_pair = m_mod_meta_database.find(modname);
+	if (mod_pair == m_mod_meta_database.end())
+		return false;
+	const StringMap &meta = mod_pair->second;
+
+	auto pair = meta.find(key);
+	if (pair != meta.end()) {
+		*value = pair->second;
+		return true;
+	}
+	return false;
+}
+
+bool Database_Dummy::hasModEntry(const std::string &modname, const std::string &key)
+{
+	auto mod_pair = m_mod_meta_database.find(modname);
+	if (mod_pair == m_mod_meta_database.end())
+		return false;
+	const StringMap &meta = mod_pair->second;
+
+	return meta.find(key) != meta.cend();
+}
+
 bool Database_Dummy::setModEntry(const std::string &modname,
 	const std::string &key, const std::string &value)
 {
@@ -112,6 +138,16 @@ bool Database_Dummy::removeModEntry(const std::string &modname, const std::strin
 	return false;
 }
 
+bool Database_Dummy::removeModEntries(const std::string &modname)
+{
+	auto mod_pair = m_mod_meta_database.find(modname);
+	if (mod_pair != m_mod_meta_database.end() && !mod_pair->second.empty()) {
+		mod_pair->second.clear();
+		return true;
+	}
+	return false;
+}
+
 void Database_Dummy::listMods(std::vector<std::string> *res)
 {
 	for (const auto &pair : m_mod_meta_database) {
diff --git a/src/database/database-dummy.h b/src/database/database-dummy.h
index 44b9e8d68..86c680ef1 100644
--- a/src/database/database-dummy.h
+++ b/src/database/database-dummy.h
@@ -38,9 +38,13 @@ public:
 	void listPlayers(std::vector<std::string> &res);
 
 	bool getModEntries(const std::string &modname, StringMap *storage);
+	bool getModEntry(const std::string &modname,
+			const std::string &key, std::string *value);
+	bool hasModEntry(const std::string &modname, const std::string &key);
 	bool setModEntry(const std::string &modname,
 			const std::string &key, const std::string &value);
 	bool removeModEntry(const std::string &modname, const std::string &key);
+	bool removeModEntries(const std::string &modname);
 	void listMods(std::vector<std::string> *res);
 
 	void beginSave() {}
diff --git a/src/database/database-files.cpp b/src/database/database-files.cpp
index 00bc6d765..eff08de12 100644
--- a/src/database/database-files.cpp
+++ b/src/database/database-files.cpp
@@ -396,6 +396,26 @@ bool ModMetadataDatabaseFiles::getModEntries(const std::string &modname, StringM
 	return true;
 }
 
+bool ModMetadataDatabaseFiles::getModEntry(const std::string &modname,
+	const std::string &key, std::string *value)
+{
+	Json::Value *meta = getOrCreateJson(modname);
+	if (!meta)
+		return false;
+
+	if (meta->isMember(key)) {
+		*value = (*meta)[key].asString();
+		return true;
+	}
+	return false;
+}
+
+bool ModMetadataDatabaseFiles::hasModEntry(const std::string &modname, const std::string &key)
+{
+	Json::Value *meta = getOrCreateJson(modname);
+	return meta && meta->isMember(key);
+}
+
 bool ModMetadataDatabaseFiles::setModEntry(const std::string &modname,
 	const std::string &key, const std::string &value)
 {
@@ -424,6 +444,17 @@ bool ModMetadataDatabaseFiles::removeModEntry(const std::string &modname,
 	return false;
 }
 
+bool ModMetadataDatabaseFiles::removeModEntries(const std::string &modname)
+{
+	Json::Value *meta = getOrCreateJson(modname);
+	if (!meta || meta->empty())
+		return false;
+
+	meta->clear();
+	m_modified.insert(modname);
+	return true;
+}
+
 void ModMetadataDatabaseFiles::beginSave()
 {
 }
diff --git a/src/database/database-files.h b/src/database/database-files.h
index 962e4d7bb..089e071fe 100644
--- a/src/database/database-files.h
+++ b/src/database/database-files.h
@@ -79,9 +79,13 @@ public:
 	virtual ~ModMetadataDatabaseFiles() = default;
 
 	virtual bool getModEntries(const std::string &modname, StringMap *storage);
+	virtual bool getModEntry(const std::string &modname,
+		const std::string &key, std::string *value);
+	virtual bool hasModEntry(const std::string &modname, const std::string &key);
 	virtual bool setModEntry(const std::string &modname,
 		const std::string &key, const std::string &value);
 	virtual bool removeModEntry(const std::string &modname, const std::string &key);
+	virtual bool removeModEntries(const std::string &modname);
 	virtual void listMods(std::vector<std::string> *res);
 
 	virtual void beginSave();
diff --git a/src/database/database-sqlite3.cpp b/src/database/database-sqlite3.cpp
index 5e565be55..0406fadc8 100644
--- a/src/database/database-sqlite3.cpp
+++ b/src/database/database-sqlite3.cpp
@@ -770,9 +770,12 @@ ModMetadataDatabaseSQLite3::ModMetadataDatabaseSQLite3(const std::string &savedi
 
 ModMetadataDatabaseSQLite3::~ModMetadataDatabaseSQLite3()
 {
+	FINALIZE_STATEMENT(m_stmt_remove_all)
 	FINALIZE_STATEMENT(m_stmt_remove)
 	FINALIZE_STATEMENT(m_stmt_set)
+	FINALIZE_STATEMENT(m_stmt_has)
 	FINALIZE_STATEMENT(m_stmt_get)
+	FINALIZE_STATEMENT(m_stmt_get_all)
 }
 
 void ModMetadataDatabaseSQLite3::createDatabase()
@@ -792,31 +795,74 @@ void ModMetadataDatabaseSQLite3::createDatabase()
 
 void ModMetadataDatabaseSQLite3::initStatements()
 {
-	PREPARE_STATEMENT(get, "SELECT `key`, `value` FROM `entries` WHERE `modname` = ?");
+	PREPARE_STATEMENT(get_all, "SELECT `key`, `value` FROM `entries` WHERE `modname` = ?");
+	PREPARE_STATEMENT(get,
+		"SELECT `value` FROM `entries` WHERE `modname` = ? AND `key` = ? LIMIT 1");
+	PREPARE_STATEMENT(has,
+		"SELECT 1 FROM `entries` WHERE `modname` = ? AND `key` = ? LIMIT 1");
 	PREPARE_STATEMENT(set,
 		"REPLACE INTO `entries` (`modname`, `key`, `value`) VALUES (?, ?, ?)");
 	PREPARE_STATEMENT(remove, "DELETE FROM `entries` WHERE `modname` = ? AND `key` = ?");
+	PREPARE_STATEMENT(remove_all, "DELETE FROM `entries` WHERE `modname` = ?");
 }
 
 bool ModMetadataDatabaseSQLite3::getModEntries(const std::string &modname, StringMap *storage)
 {
 	verifyDatabase();
 
-	str_to_sqlite(m_stmt_get, 1, modname);
-	while (sqlite3_step(m_stmt_get) == SQLITE_ROW) {
-		const char *key_data = (const char *) sqlite3_column_blob(m_stmt_get, 0);
-		size_t key_len = sqlite3_column_bytes(m_stmt_get, 0);
-		const char *value_data = (const char *) sqlite3_column_blob(m_stmt_get, 1);
-		size_t value_len = sqlite3_column_bytes(m_stmt_get, 1);
+	str_to_sqlite(m_stmt_get_all, 1, modname);
+	while (sqlite3_step(m_stmt_get_all) == SQLITE_ROW) {
+		const char *key_data = (const char *) sqlite3_column_blob(m_stmt_get_all, 0);
+		size_t key_len = sqlite3_column_bytes(m_stmt_get_all, 0);
+		const char *value_data = (const char *) sqlite3_column_blob(m_stmt_get_all, 1);
+		size_t value_len = sqlite3_column_bytes(m_stmt_get_all, 1);
 		(*storage)[std::string(key_data, key_len)] = std::string(value_data, value_len);
 	}
 	sqlite3_vrfy(sqlite3_errcode(m_database), SQLITE_DONE);
 
-	sqlite3_reset(m_stmt_get);
+	sqlite3_reset(m_stmt_get_all);
 
 	return true;
 }
 
+bool ModMetadataDatabaseSQLite3::getModEntry(const std::string &modname,
+	const std::string &key, std::string *value)
+{
+	verifyDatabase();
+
+	str_to_sqlite(m_stmt_get, 1, modname);
+	SQLOK(sqlite3_bind_blob(m_stmt_get, 2, key.data(), key.size(), NULL),
+		"Internal error: failed to bind query at " __FILE__ ":" TOSTRING(__LINE__));
+	bool found = sqlite3_step(m_stmt_get) == SQLITE_ROW;
+	if (found) {
+		const char *value_data = (const char *) sqlite3_column_blob(m_stmt_get, 0);
+		size_t value_len = sqlite3_column_bytes(m_stmt_get, 0);
+		value->assign(value_data, value_len);
+		sqlite3_step(m_stmt_get);
+	}
+
+	sqlite3_reset(m_stmt_get);
+
+	return found;
+}
+
+bool ModMetadataDatabaseSQLite3::hasModEntry(const std::string &modname,
+		const std::string &key)
+{
+	verifyDatabase();
+
+	str_to_sqlite(m_stmt_has, 1, modname);
+	SQLOK(sqlite3_bind_blob(m_stmt_has, 2, key.data(), key.size(), NULL),
+		"Internal error: failed to bind query at " __FILE__ ":" TOSTRING(__LINE__));
+	bool found = sqlite3_step(m_stmt_has) == SQLITE_ROW;
+	if (found)
+		sqlite3_step(m_stmt_has);
+
+	sqlite3_reset(m_stmt_has);
+
+	return found;
+}
+
 bool ModMetadataDatabaseSQLite3::setModEntry(const std::string &modname,
 	const std::string &key, const std::string &value)
 {
@@ -850,6 +896,19 @@ bool ModMetadataDatabaseSQLite3::removeModEntry(const std::string &modname,
 	return changes > 0;
 }
 
+bool ModMetadataDatabaseSQLite3::removeModEntries(const std::string &modname)
+{
+	verifyDatabase();
+
+	str_to_sqlite(m_stmt_remove_all, 1, modname);
+	sqlite3_vrfy(sqlite3_step(m_stmt_remove_all), SQLITE_DONE);
+	int changes = sqlite3_changes(m_database);
+
+	sqlite3_reset(m_stmt_remove_all);
+
+	return changes > 0;
+}
+
 void ModMetadataDatabaseSQLite3::listMods(std::vector<std::string> *res)
 {
 	verifyDatabase();
diff --git a/src/database/database-sqlite3.h b/src/database/database-sqlite3.h
index 5e3d7c96c..566f6cebb 100644
--- a/src/database/database-sqlite3.h
+++ b/src/database/database-sqlite3.h
@@ -240,9 +240,13 @@ public:
 	virtual ~ModMetadataDatabaseSQLite3();
 
 	virtual bool getModEntries(const std::string &modname, StringMap *storage);
+	virtual bool getModEntry(const std::string &modname,
+		const std::string &key, std::string *value);
+	virtual bool hasModEntry(const std::string &modname, const std::string &key);
 	virtual bool setModEntry(const std::string &modname,
 		const std::string &key, const std::string &value);
 	virtual bool removeModEntry(const std::string &modname, const std::string &key);
+	virtual bool removeModEntries(const std::string &modname);
 	virtual void listMods(std::vector<std::string> *res);
 
 	virtual void beginSave() { Database_SQLite3::beginSave(); }
@@ -253,7 +257,10 @@ protected:
 	virtual void initStatements();
 
 private:
+	sqlite3_stmt *m_stmt_get_all = nullptr;
 	sqlite3_stmt *m_stmt_get = nullptr;
+	sqlite3_stmt *m_stmt_has = nullptr;
 	sqlite3_stmt *m_stmt_set = nullptr;
 	sqlite3_stmt *m_stmt_remove = nullptr;
+	sqlite3_stmt *m_stmt_remove_all = nullptr;
 };
diff --git a/src/database/database.h b/src/database/database.h
index fbb5befea..0f22deebc 100644
--- a/src/database/database.h
+++ b/src/database/database.h
@@ -92,8 +92,12 @@ public:
 	virtual ~ModMetadataDatabase() = default;
 
 	virtual bool getModEntries(const std::string &modname, StringMap *storage) = 0;
+	virtual bool hasModEntry(const std::string &modname, const std::string &key) = 0;
+	virtual bool getModEntry(const std::string &modname,
+		const std::string &key, std::string *value) = 0;
 	virtual bool setModEntry(const std::string &modname,
 		const std::string &key, const std::string &value) = 0;
 	virtual bool removeModEntry(const std::string &modname, const std::string &key) = 0;
+	virtual bool removeModEntries(const std::string &modname) = 0;
 	virtual void listMods(std::vector<std::string> *res) = 0;
 };