Method ControlFile

src/remote/server/ReplServer.cpp:152–220

	public:
		ControlFile(const PathName& directory,
					const Guid& guid, FB_UINT64 sequence,
					TransactionList& transactions)
			: AutoFile(init(directory, guid))
		{
			char guidStr[GUID_BUFF_SIZE];
			GuidToString(guidStr, &guid);

			const PathName filename = directory + guidStr;

#ifdef WIN_NT
			string name;
			name.printf("firebird_replctl_%s", guidStr);
			m_mutex = CreateMutex(ISC_get_security_desc(), FALSE, name.c_str());
			if (WaitForSingleObject(m_mutex, INFINITE) != WAIT_OBJECT_0)
#else // POSIX
#ifdef HAVE_FLOCK
			if (flock(m_handle, LOCK_EX))
#else
			if (lockf(m_handle, F_LOCK, 0))
#endif
#endif
			{
				raiseError("Control file %s lock failed (error: %d)", filename.c_str(), ERRNO);
			}

			memset(&m_data, 0, sizeof(Data));
			strcpy(m_data.signature, CTL_SIGNATURE);
			m_data.version = CTL_CURRENT_VERSION;

			const size_t length = (size_t) lseek(m_handle, 0, SEEK_END);

			if (!length)
			{
				m_data.sequence = sequence ? sequence - 1 : 0;
				m_data.offset = 0;
				m_data.db_sequence = 0;

				lseek(m_handle, 0, SEEK_SET);
				if (write(m_handle, &m_data, sizeof(Data)) != sizeof(Data))
					raiseError("Control file %s cannot be written", filename.c_str());
 			}
			else if (length >= sizeof(DataV1))
			{
				lseek(m_handle, 0, SEEK_SET);
				if (read(m_handle, &m_data, sizeof(DataV1)) != sizeof(DataV1))
					raiseError("Control file %s appears corrupted", filename.c_str());

				if (strcmp(m_data.signature, CTL_SIGNATURE) ||
					(m_data.version != CTL_VERSION1))
				{
					raiseError("Control file %s appears corrupted", filename.c_str());
				}

				ActiveTransaction* const ptr =
					m_data.txn_count ? transactions.getBuffer(m_data.txn_count) : NULL;
				const ULONG txn_size = m_data.txn_count * sizeof(ActiveTransaction);