sockfilt.c: clean up threaded approach and add documentation (42c04eb1) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP curl

tests/server/sockfilt.c

+137 −48

Original line number	Diff line number	Diff line
		@@ -506,102 +506,170 @@ static void lograw(unsigned char *buffer, ssize_t len)
		* to re-create a select() function with support for other handle types.
		*
		* select() function with support for WINSOCK2 sockets and all
		* other handle types supported by WaitForMultipleObjectsEx().
		*
		* TODO: Differentiate between read/write/except for non-SOCKET handles.
		* other handle types supported by WaitForMultipleObjectsEx() as
		* well as disk files, anonymous and names pipes, and character input.
		*
		* http://msdn.microsoft.com/en-us/library/windows/desktop/ms687028.aspx
		* http://msdn.microsoft.com/en-us/library/windows/desktop/ms741572.aspx
		*/
		static DWORD WINAPI select_ws_stdin_wait_thread(LPVOID lpParameter)
		struct select_ws_wait_data {
		HANDLE handle; /* actual handle to wait for during select */
		HANDLE event; /* internal event to abort waiting thread */
		};
		static DWORD WINAPI select_ws_wait_thread(LPVOID lpParameter)
		{
		struct select_ws_wait_data *data;
		HANDLE handle, handles[2];
		INPUT_RECORD inputrecord;
		LARGE_INTEGER size, pos;
		DWORD type, length;

		handle = GetStdHandle(STD_INPUT_HANDLE);
		handles[0] = (HANDLE) lpParameter;
		/* retrieve handles from internal structure */
		data = (struct select_ws_wait_data *) lpParameter;
		if(data) {
		handle = data->handle;
		handles[0] = data->event;
		handles[1] = handle;
		type = GetFileType(handle);
		free(data);
		}
		else
		return -1;

		/* retrieve the type of file to wait on */
		type = GetFileType(handle);
		switch(type) {
		case FILE_TYPE_DISK:
		/* The handle represents a file on disk, this means:
		* - WaitForMultipleObjectsEx will always be signalled for it.
		* - comparison of current position in file and total size of
		* the file can be used to check if we reached the end yet.
		*
		* Approach: Loop till either the internal event is signalled
		* or if the end of the file has already been reached.
		*/
		while(WaitForMultipleObjectsEx(2, handles, FALSE, INFINITE, FALSE)
		== WAIT_OBJECT_0 + 1) {
		/* get total size of file */
		size.QuadPart = 0;
		if(GetFileSizeEx(handle, &size)) {
		/* get the current position within the file */
		pos.QuadPart = 0;
		if(SetFilePointerEx(handle, pos, &pos, FILE_CURRENT)) {
		if(size.QuadPart == pos.QuadPart)
		/* compare position with size, abort if not equal */
		if(size.QuadPart == pos.QuadPart) {
		/* sleep and continue waiting */
		SleepEx(100, FALSE);
		else
		break;
		continue;
		}
		else
		break;
		}
		else
		}
		/* there is some data available, stop waiting */
		break;
		}
		break;

		case FILE_TYPE_CHAR:
		/* The handle represents a character input, this means:
		* - WaitForMultipleObjectsEx will be signalled on any kind of input,
		* including mouse and window size events we do not care about.
		*
		* Approach: Loop till either the internal event is signalled
		* or we get signalled for an actual key-event.
		*/
		while(WaitForMultipleObjectsEx(2, handles, FALSE, INFINITE, FALSE)
		== WAIT_OBJECT_0 + 1) {
		/* check if this is an actual console handle */
		if(GetConsoleMode(handle, &length)) {
		/* retrieve an event from the console buffer */
		length = 0;
		if(PeekConsoleInput(handle, &inputrecord, 1, &length)) {
		if(length == 1 && inputrecord.EventType != KEY_EVENT)
		/* check if the event is not an actual key-event */
		if(length == 1 && inputrecord.EventType != KEY_EVENT) {
		/* purge the non-key-event and continue waiting */
		ReadConsoleInput(handle, &inputrecord, 1, &length);
		else
		break;
		continue;
		}
		else
		break;
		}
		else
		}
		/* there is some data available, stop waiting */
		break;
		}
		break;

		case FILE_TYPE_PIPE:
		/* The handle represents an anonymous or named pipe, this means:
		* - WaitForMultipleObjectsEx will always be signalled for it.
		* - peek into the pipe and retrieve the amount of data available.
		*
		* Approach: Loop till either the internal event is signalled
		* or there is data in the pipe available for reading.
		*/
		while(WaitForMultipleObjectsEx(2, handles, FALSE, INFINITE, FALSE)
		== WAIT_OBJECT_0 + 1) {
		/* peek into the pipe and retrieve the amount of data available */
		if(PeekNamedPipe(handle, NULL, 0, NULL, &length, NULL)) {
		if(length == 0)
		/* if there is no data available, sleep and continue waiting */
		if(length == 0) {
		SleepEx(100, FALSE);
		else
		break;
		continue;
		}
		}
		else {
		if(GetLastError() == ERROR_BROKEN_PIPE)
		/* if the pipe has been closed, sleep and continue waiting */
		if(GetLastError() == ERROR_BROKEN_PIPE) {
		SleepEx(100, FALSE);
		else
		break;
		continue;
		}
		}
		/* there is some data available, stop waiting */
		break;
		}
		break;

		default:
		/* The handle has an unknown type, try to wait on it */
		WaitForMultipleObjectsEx(2, handles, FALSE, INFINITE, FALSE);
		break;
		}

		return 0;
		}
		static HANDLE select_ws_wait(HANDLE handle, HANDLE event)
		{
		struct select_ws_wait_data *data;
		HANDLE thread = NULL;

		/* allocate internal waiting data structure */
		data = malloc(sizeof(struct select_ws_wait_data));
		if(data) {
		data->handle = handle;
		data->event = event;

		/* launch waiting thread */
		thread = CreateThread(NULL, 0,
		&select_ws_wait_thread,
		data, 0, NULL);

		/* free data if thread failed to launch */
		if(!thread) {
		free(data);
		}
		}

		return thread;
		}
		static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		fd_set exceptfds, struct timeval timeout)
		{
		DWORD milliseconds, wait, idx;
		WSAEVENT wsaevent, *wsaevents;
		WSANETWORKEVENTS wsanetevents;
		HANDLE handle, *handles;
		HANDLE handle, handles, threads;
		curl_socket_t sock, fdarr, wsasocks;
		long networkevents;
		int error, fds;
		HANDLE threadevent = NULL, threadhandle = NULL;
		DWORD nfd = 0, wsa = 0;
		HANDLE waitevent = NULL;
		DWORD nfd = 0, thd = 0, wsa = 0;
		int ret = 0;

		/* check if the input value is valid */
		@@ -616,6 +684,13 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		return 0;
		}

		/* create internal event to signal waiting threads */
		waitevent = CreateEvent(NULL, TRUE, FALSE, NULL);
		if(!waitevent) {
		errno = ENOMEM;
		return -1;
		}

		/* allocate internal array for the original input handles */
		fdarr = malloc(nfds * sizeof(curl_socket_t));
		if(fdarr == NULL) {
		@@ -631,9 +706,19 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		return -1;
		}

		/* allocate internal array for the internal threads handles */
		threads = malloc(nfds * sizeof(HANDLE));
		if(threads == NULL) {
		free(handles);
		free(fdarr);
		errno = ENOMEM;
		return -1;
		}

		/* allocate internal array for the internal socket handles */
		wsasocks = malloc(nfds * sizeof(curl_socket_t));
		if(wsasocks == NULL) {
		free(threads);
		free(handles);
		free(fdarr);
		errno = ENOMEM;
		@@ -643,6 +728,7 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		/* allocate internal array for the internal WINSOCK2 events */
		wsaevents = malloc(nfds * sizeof(WSAEVENT));
		if(wsaevents == NULL) {
		free(threads);
		free(wsasocks);
		free(handles);
		free(fdarr);
		@@ -668,11 +754,11 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		if(networkevents) {
		fdarr[nfd] = curlx_sitosk(fds);
		if(fds == fileno(stdin)) {
		threadevent = CreateEvent(NULL, TRUE, FALSE, NULL);
		threadhandle = CreateThread(NULL, 0,
		&select_ws_stdin_wait_thread,
		threadevent, 0, NULL);
		handles[nfd] = threadhandle;
		handle = GetStdHandle(STD_INPUT_HANDLE);
		handle = select_ws_wait(handle, waitevent);
		handles[nfd] = handle;
		threads[thd] = handle;
		thd++;
		}
		else if(fds == fileno(stdout)) {
		handles[nfd] = GetStdHandle(STD_OUTPUT_HANDLE);
		@@ -685,14 +771,19 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		if(wsaevent != WSA_INVALID_EVENT) {
		error = WSAEventSelect(fds, wsaevent, networkevents);
		if(error != SOCKET_ERROR) {
		handles[nfd] = wsaevent;
		handle = (HANDLE) wsaevent;
		handles[nfd] = handle;
		wsasocks[wsa] = curlx_sitosk(fds);
		wsaevents[wsa] = wsaevent;
		wsa++;
		}
		else {
		handles[nfd] = (HANDLE) curlx_sitosk(fds);
		WSACloseEvent(wsaevent);
		handle = (HANDLE) curlx_sitosk(fds);
		handle = select_ws_wait(handle, waitevent);
		handles[nfd] = handle;
		threads[thd] = handle;
		thd++;
		}
		}
		}
		@@ -711,10 +802,8 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		/* wait for one of the internal handles to trigger */
		wait = WaitForMultipleObjectsEx(nfd, handles, FALSE, milliseconds, FALSE);

		/* signal the event handle for the waiting thread */
		if(threadevent) {
		SetEvent(threadevent);
		}
		/* signal the event handle for the waiting threads */
		SetEvent(waitevent);

		/* loop over the internal handles returned in the descriptors */
		for(idx = 0; idx < nfd; idx++) {
		@@ -783,16 +872,16 @@ static int select_ws(int nfds, fd_set readfds, fd_set writefds,
		WSACloseEvent(wsaevents[idx]);
		}

		if(threadhandle) {
		WaitForSingleObject(threadhandle, INFINITE);
		CloseHandle(threadhandle);
		}
		if(threadevent) {
		CloseHandle(threadevent);
		for(idx = 0; idx < thd; idx++) {
		WaitForSingleObject(threads[thd], INFINITE);
		CloseHandle(threads[thd]);
		}

		CloseHandle(waitevent);

		free(wsaevents);
		free(wsasocks);
		free(threads);
		free(handles);
		free(fdarr);