Win32: Shutdown the accept/listen threads a bit more gracefully. (f9bed5df) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP Apache Httpd

server/mpm/winnt/mpm_winnt.c

+46 −33

Changes for server/mpm/winnt/mpm_winnt.c: 46 added lines, 33 removed lines.
Original line number	Diff line number	Diff line
		@@ -215,6 +215,7 @@ AP_DECLARE(void) mpm_recycle_completion_context(PCOMP_CONTEXT context)
		if (context) {
		apr_pool_clear(context->ptrans);
		context->next = NULL;
		ResetEvent(context->Overlapped.hEvent);
		apr_thread_mutex_lock(qlock);
		if (qtail)
		qtail->next = context;
		@@ -261,7 +262,7 @@ AP_DECLARE(PCOMP_CONTEXT) mpm_get_completion_context(void)
		*/
		context = (PCOMP_CONTEXT) apr_pcalloc(pchild, sizeof(COMP_CONTEXT));

		context->Overlapped.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
		context->Overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
		if (context->Overlapped.hEvent == NULL) {
		/* Hopefully this is a temporary condition ... */
		ap_log_error(APLOG_MARK,APLOG_WARNING, apr_get_os_error(), ap_server_conf,
		@@ -926,25 +927,23 @@ static PCOMP_CONTEXT win9x_get_connection(PCOMP_CONTEXT context)
		static void winnt_accept(void *listen_socket)
		{
		apr_os_sock_info_t sockinfo;
		PCOMP_CONTEXT context;
		PCOMP_CONTEXT context = NULL;
		DWORD BytesRead;
		SOCKET nlsd;
		int lasterror;
		int rv;

		nlsd = (SOCKET) listen_socket;

		while (!shutdown_in_progress) {
		if (!context) {
		context = mpm_get_completion_context();
		if (!context) {
		/* Hopefully whatever is preventing us from getting a
		* completion context is a temporary resource constraint.
		* Yield the rest of our time slice.
		*/
		/* Temporary resource constraint? */
		Sleep(0);
		continue;
		}
		}

		again:
		/* Create and initialize the accept socket */
		if (context->accept_socket == INVALID_SOCKET) {
		context->accept_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
		@@ -954,7 +953,7 @@ static void winnt_accept(void *listen_socket)
		"winnt_accept: Failed to allocate an accept socket. "
		"Temporary resource constraint? Try again.");
		Sleep(100);
		goto again;
		continue;
		}
		}

		@@ -968,41 +967,53 @@ static void winnt_accept(void *listen_socket)
		PADDED_ADDR_SIZE,
		&BytesRead,
		&context->Overlapped)) {
		lasterror = apr_get_netos_error();
		if (lasterror == APR_FROM_OS_ERROR(WSAEINVAL)) {
		rv = apr_get_netos_error();
		if (rv == APR_FROM_OS_ERROR(WSAEINVAL)) {
		/* Hack alert. Occasionally, TransmitFile will not recycle the
		* accept socket (usually when the client disconnects early).
		* Get a new socket and try the call again.
		*/
		closesocket(context->accept_socket);
		context->accept_socket = INVALID_SOCKET;
		ap_log_error(APLOG_MARK, APLOG_DEBUG, lasterror, ap_server_conf,
		ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, ap_server_conf,
		"winnt_accept: AcceptEx failed due to early client "
		"disconnect. Reallocate the accept socket and try again.");
		if (shutdown_in_progress)
		break;
		else
		goto again;
		continue;
		}
		else if (lasterror != APR_FROM_OS_ERROR(ERROR_IO_PENDING)) {
		ap_log_error(APLOG_MARK,APLOG_ERR, lasterror, ap_server_conf,
		else if (rv != APR_FROM_OS_ERROR(ERROR_IO_PENDING)) {
		ap_log_error(APLOG_MARK,APLOG_ERR, rv, ap_server_conf,
		"winnt_accept: AcceptEx failed. Attempting to recover.");
		closesocket(context->accept_socket);
		context->accept_socket = INVALID_SOCKET;
		Sleep(100);
		goto again;
		continue;
		}

		/* Wait for pending i/o */
		WaitForSingleObject(context->Overlapped.hEvent, INFINITE);
		/* Wait for pending i/o. Wake up once per second to check for shutdown */
		while (1) {
		rv = WaitForSingleObject(context->Overlapped.hEvent, 1000);
		if (rv == WAIT_OBJECT_0) {
		if (!GetOverlappedResult(context->Overlapped.hEvent,
		&context->Overlapped,
		&BytesRead, FALSE)) {
		ap_log_error(APLOG_MARK,APLOG_WARNING, GetLastError(), ap_server_conf,
		"winnt_accept: Asynchronous AcceptEx failed.");
		closesocket(context->accept_socket);
		context->accept_socket = INVALID_SOCKET;
		}

		/* ### There is a race condition here. The mainline may hit
		* WSATerminate before this thread reawakens. Look First.
		*/
		break;
		}
		/* WAIT_TIMEOUT */
		if (shutdown_in_progress) {
		closesocket(context->accept_socket);
		context->accept_socket = INVALID_SOCKET;
		break;
		}
		}
		if (context->accept_socket == INVALID_SOCKET) {
		continue;
		}
		}

		/* Inherit the listen socket settings. Required for
		* shutdown() to work
		@@ -1038,12 +1049,14 @@ static void winnt_accept(void *listen_socket)
		*/
		PostQueuedCompletionStatus(ThreadDispatchIOCP, 0, IOCP_CONNECTION_ACCEPTED,
		&context->Overlapped);
		context = NULL;
		}

		if (!shutdown_in_progress) {
		/* Yow, hit an irrecoverable error! Tell the child to die. */
		SetEvent(exit_event);
		}
		ap_log_error(APLOG_MARK, APLOG_INFO, APR_SUCCESS, ap_server_conf,
		"Child %d: Accept thread exiting.", my_pid);
		}
		static PCOMP_CONTEXT winnt_get_connection(PCOMP_CONTEXT context)
		{
		@@ -1099,6 +1112,8 @@ static void worker_main(long thread_num)
		PCOMP_CONTEXT context = NULL;
		ap_sb_handle_t *sbh;

		ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, ap_server_conf,
		"Child %d: Worker thread %d starting.", my_pid, thread_num);
		while (1) {
		conn_rec *c;
		apr_int32_t disconnected;
		@@ -1147,8 +1162,8 @@ static void worker_main(long thread_num)
		ap_update_child_status_from_indexes(0, thread_num, SERVER_DEAD,
		(request_rec *) NULL);

		ap_log_error(APLOG_MARK, APLOG_INFO, APR_SUCCESS, ap_server_conf,
		"Child %d: Thread exiting.", my_pid);
		ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, ap_server_conf,
		"Child %d: Worker thread %d exiting.", my_pid, thread_num);
		}

		static void cleanup_thread(thread handles, int thread_cnt, int thread_to_clean)
		@@ -1357,17 +1372,15 @@ static void child_main()
		*/
		shutdown_in_progress = 1;

		/* Tell the worker threads they may exit when done handling
		* a connection.
		*/
		workers_may_exit = 1;

		/* Close the listening sockets. */
		for (lr = ap_listeners; lr ; lr = lr->next) {
		apr_socket_close(lr->sd);
		}
		Sleep(1000);

		/* Tell the worker threads to exit */
		workers_may_exit = 1;

		/* Release the start_mutex to let the new process (in the restart
		* scenario) a chance to begin accepting and servicing requests
		*/