| 2206 | |
| 2207 | |
| 2208 | DDLGuard::DDLGuard(Map & map_, SharedMutex & db_mutex_, std::unique_lock<std::mutex> guards_lock_, const String & elem, const String & database_name) |
| 2209 | : map(map_), db_mutex(db_mutex_), guards_lock(std::move(guards_lock_)) |
| 2210 | { |
| 2211 | it = map.emplace(elem, Entry{std::make_unique<std::mutex>(), 0}).first; |
| 2212 | ++it->second.counter; |
| 2213 | guards_lock.unlock(); |
| 2214 | table_lock = std::unique_lock(*it->second.mutex); |
| 2215 | is_database_guard = elem.empty(); |
| 2216 | if (!is_database_guard) |
| 2217 | { |
| 2218 | static constexpr int MAX_TRY = 10; |
| 2219 | static constexpr UInt64 INTERVAL_MS = 100; |
| 2220 | bool acquired_db_mutex_lock = false; |
| 2221 | for (int i = 0; i < MAX_TRY; ++i) |
| 2222 | { |
| 2223 | acquired_db_mutex_lock = db_mutex.try_lock_shared(); |
| 2224 | if (acquired_db_mutex_lock) |
| 2225 | break; |
| 2226 | |
| 2227 | if (!DatabaseCatalog::instance().isDatabaseExist(database_name)) |
| 2228 | { |
| 2229 | releaseTableLock(); |
| 2230 | throw Exception(ErrorCodes::UNKNOWN_DATABASE, "Database {} is currently dropped or renamed", database_name); |
| 2231 | } |
| 2232 | |
| 2233 | sleepForMilliseconds(INTERVAL_MS); |
| 2234 | } |
| 2235 | if (!acquired_db_mutex_lock) |
| 2236 | { |
| 2237 | releaseTableLock(); |
| 2238 | throw Exception( |
| 2239 | ErrorCodes::TIMEOUT_EXCEEDED, |
| 2240 | "Unable to acquire the database lock of {} after {} ms", |
| 2241 | database_name, |
| 2242 | MAX_TRY * INTERVAL_MS); |
| 2243 | } |
| 2244 | } |
| 2245 | } |
| 2246 | |
| 2247 | void DDLGuard::releaseTableLock() noexcept |
| 2248 | { |
nothing calls this directly
no test coverage detected