socket.c

bind 9.3结合mysql数据库

/*
 * Dequeue an item off the given socket's read queue, set the result code
 * in the done event to the one provided, and send it to the task it was
 * destined for.
 *
 * If the event to be sent is on a list, remove it before sending.  If
 * asked to, send and detach from the socket as well.
 *
 * Caller must have the socket locked if the event is attached to the socket.
 */
static void
send_recvdone_event(isc_socket_t *sock, isc_socketevent_t **dev) {
	isc_task_t *task;

	task = (*dev)->ev_sender;

	(*dev)->ev_sender = sock;

	if (ISC_LINK_LINKED(*dev, ev_link)) {
		ISC_LIST_DEQUEUE(sock->recv_list, *dev, ev_link);
	}

	if (((*dev)->attributes & ISC_SOCKEVENTATTR_ATTACHED)
	    == ISC_SOCKEVENTATTR_ATTACHED)
		isc_task_sendanddetach(&task, (isc_event_t **)dev);
	else
		isc_task_send(task, (isc_event_t **)dev);
}

/*
 * See comments for send_recvdone_event() above.
 *
 * Caller must have the socket locked if the event is attached to the socket.
 */
static void
send_senddone_event(isc_socket_t *sock, isc_socketevent_t **dev) {
	isc_task_t *task;

	INSIST(dev != NULL && *dev != NULL);

	task = (*dev)->ev_sender;
	(*dev)->ev_sender = sock;

	if (ISC_LINK_LINKED(*dev, ev_link)) {
		ISC_LIST_DEQUEUE(sock->send_list, *dev, ev_link);
	}

	if (((*dev)->attributes & ISC_SOCKEVENTATTR_ATTACHED)
	    == ISC_SOCKEVENTATTR_ATTACHED)
		isc_task_sendanddetach(&task, (isc_event_t **)dev);
	else
		isc_task_send(task, (isc_event_t **)dev);
}

/*
 * Call accept() on a socket, to get the new file descriptor.  The listen
 * socket is used as a prototype to create a new isc_socket_t.  The new
 * socket has one outstanding reference.  The task receiving the event
 * will be detached from just after the event is delivered.
 *
 * On entry to this function, the event delivered is the internal
 * readable event, and the first item on the accept_list should be
 * the done event we want to send.  If the list is empty, this is a no-op,
 * so just unlock and return.
 */
static void
internal_accept(isc_socket_t *sock, int accept_errno) {
	isc_socketmgr_t *manager;
	isc_socket_newconnev_t *dev;
	isc_task_t *task;
	ISC_SOCKADDR_LEN_T addrlen;
	SOCKET fd;
	isc_result_t result = ISC_R_SUCCESS;
	char strbuf[ISC_STRERRORSIZE];

	INSIST(VALID_SOCKET(sock));

	LOCK(&sock->lock);
	socket_log(sock, NULL, TRACE,
		   isc_msgcat, ISC_MSGSET_SOCKET, ISC_MSG_ACCEPTLOCK,
		   "internal_accept called, locked socket");

	manager = sock->manager;
	INSIST(VALID_MANAGER(manager));

	INSIST(sock->listener);
	INSIST(sock->hEvent != NULL);
	INSIST(sock->pending_accept == 1);
	sock->pending_accept = 0;

	/*
	 * Check any possible error status from the event notification here.
	 * Note that we don't take any action since it was only
	 * Windows that was notifying about a network event, not the
	 * application.
	 * PDMXXX: Should we care about any of the possible event errors
	 *	   signalled? The only possible valid errors are:
	 *	   WSAENETDOWN, WSAECONNRESET, & WSAECONNABORTED
	 */
	if (accept_errno != 0) {
		switch (accept_errno) {
		case WSAENETDOWN:
		case WSAECONNRESET:
		case WSAECONNABORTED:
			break;		/* Expected errors */
		default:
			isc__strerror(accept_errno, strbuf, sizeof(strbuf));
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "internal_accept: from event wait: %s",
					 strbuf);
			break;
		}
		UNLOCK(&sock->lock);
		return;
	}
	
	/*
	 * Get the first item off the accept list.
	 * If it is empty, unlock the socket and return.
	 */
	dev = ISC_LIST_HEAD(sock->accept_list);
	if (dev == NULL) {
		isc_sockaddr_t from;
		/*
		 * This should only happen if WSAEventSelect() fails
		 * below or in isc_socket_cancel().
		 */
		addrlen = sizeof(from.type);
		fd = accept(sock->fd, &from.type.sa, &addrlen);
		if (fd != INVALID_SOCKET) {
			char addrbuf[ISC_SOCKADDR_FORMATSIZE];
			isc_sockaddr_format(&from, addrbuf, sizeof(addrbuf));
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "sock->accept_list empty: "
					 "dropping TCP request from %s",
					 addrbuf);
			(void)closesocket(fd);
		}
		UNLOCK(&sock->lock);
		return;
	}

	/*
	 * Try to accept the new connection.  If the accept fails with
	 * EAGAIN or EINTR, the event wait will be notified again since
	 * the event will be reset on return to caller.
	 */
	addrlen = sizeof(dev->newsocket->address.type);
	memset(&dev->newsocket->address.type.sa, 0, addrlen);
	fd = accept(sock->fd, &dev->newsocket->address.type.sa,
		    (void *)&addrlen);
	if (fd == INVALID_SOCKET) {
		accept_errno = WSAGetLastError();
		if (SOFT_ERROR(accept_errno) || accept_errno == WSAECONNRESET) {
			goto soft_error;
		} else {
			isc__strerror(accept_errno, strbuf, sizeof(strbuf));
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "internal_accept: accept() %s: %s",
					 isc_msgcat_get(isc_msgcat,
							ISC_MSGSET_GENERAL,
							ISC_MSG_FAILED,
							"failed"),
					 strbuf);
			fd = INVALID_SOCKET;
			result = ISC_R_UNEXPECTED;
		}
	} else {
		if (addrlen == 0) {
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "internal_accept(): "
					 "accept() failed to return "
					 "remote address");

			(void)closesocket(fd);
			goto soft_error;
		} else if (dev->newsocket->address.type.sa.sa_family !=
			   sock->pf)
		{
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "internal_accept(): "
					 "accept() returned peer address "
					 "family %u (expected %u)", 
					 dev->newsocket->address.
					 type.sa.sa_family,
					 sock->pf);
			(void)closesocket(fd);
			goto soft_error;
		}
	}

	if (fd != INVALID_SOCKET) {
		dev->newsocket->address.length = addrlen;
		dev->newsocket->pf = sock->pf;
	}

	/*
	 * Pull off the done event.
	 */
	ISC_LIST_UNLINK(sock->accept_list, dev, ev_link);

	/*
	 * Stop listing for connects.
	 */
	if (ISC_LIST_EMPTY(sock->accept_list) &&
	    WSAEventSelect(sock->fd, sock->hEvent, FD_CLOSE) != 0) {
		int stat;
		const char *msg;
		stat = WSAGetLastError();
		isc__strerror(stat, strbuf, sizeof(strbuf));
		msg = isc_msgcat_get(isc_msgcat, ISC_MSGSET_GENERAL,	
				     ISC_MSG_FAILED, "failed");
		UNEXPECTED_ERROR(__FILE__, __LINE__, "WSAEventSelect: %s: %s",
				 msg, strbuf);
	}

	UNLOCK(&sock->lock);

	if (fd != INVALID_SOCKET) {
		isc_result_t tresult;
		tresult = make_nonblock(fd);
		if (tresult != ISC_R_SUCCESS) {
			closesocket(fd);
			fd = INVALID_SOCKET;
			result = tresult;
		}
	}

	/*
	 * INVALID_SOCKET means the new socket didn't happen.
	 */
	if (fd != INVALID_SOCKET) {
		LOCK(&manager->lock);
		ISC_LIST_APPEND(manager->socklist, dev->newsocket, link);

		dev->newsocket->fd = fd;
		dev->newsocket->bound = 1;
		dev->newsocket->connected = 1;

		/*
		 * The accept socket inherits the listen socket's
		 * selected events. Remove this socket from all events
		 * as it is handled by IOCP. (Joe Quanaim, lucent.com)
		 */
		if (WSAEventSelect(dev->newsocket->fd, 0, 0) != 0) {
			/* this is an unlikely but non-fatal error */
			int stat;
			const char *msg;
			stat = WSAGetLastError();
			isc__strerror(stat, strbuf, sizeof(strbuf));
			msg = isc_msgcat_get(isc_msgcat, ISC_MSGSET_GENERAL,	
					     ISC_MSG_FAILED, "failed");
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "WSAEventSelect: %s: %s", msg, strbuf);
		}

		/*
		 * Save away the remote address
		 */
		dev->address = dev->newsocket->address;

		socket_log(sock, &dev->newsocket->address, CREATION,
			   isc_msgcat, ISC_MSGSET_SOCKET, ISC_MSG_ACCEPTEDCXN,
			   "accepted connection, new socket %p",
			   dev->newsocket);

		UNLOCK(&manager->lock);
	} else {
		dev->newsocket->references--;
		free_socket(&dev->newsocket);
	}

	/*
	 * Fill in the done event details and send it off.
	 */
	dev->result = result;
	task = dev->ev_sender;
	dev->ev_sender = sock;

	isc_task_sendanddetach(&task, (isc_event_t **)&dev);
	return;

 soft_error:
	UNLOCK(&sock->lock);
	return;
}

/*
 * Called when a socket with a pending connect() finishes.
 */
static void
internal_connect(isc_socket_t *sock, int connect_errno) {
	isc_socket_connev_t *dev;
	isc_task_t *task;
	char strbuf[ISC_STRERRORSIZE];

	INSIST(VALID_SOCKET(sock));

	LOCK(&sock->lock);

	/*
	 * Has this event been canceled?
	 */
	dev = sock->connect_ev;
	if (dev == NULL) {
		INSIST(!sock->connecting);
		UNLOCK(&sock->lock);
		return;
	}

	INSIST(sock->connecting);
	sock->connecting = 0;

	/*
	 * Check possible Windows network event error status here.
	 */
	if (connect_errno != 0) {
		/*
		 * If the error is EAGAIN, just try again on this
		 * fd and pretend nothing strange happened.
		 */
		if (SOFT_ERROR(connect_errno) ||
		    connect_errno == WSAEINPROGRESS)
		{
			sock->connecting = 1;
			UNLOCK(&sock->lock);
			return;
		}

		/*
		 * Translate other errors into ISC_R_* flavors.
		 */
		switch (connect_errno) {
#define ERROR_MATCH(a, b) case a: dev->result = b; break;
			ERROR_MATCH(WSAEACCES, ISC_R_NOPERM);
			ERROR_MATCH(WSAEADDRNOTAVAIL, ISC_R_ADDRNOTAVAIL);
			ERROR_MATCH(WSAEAFNOSUPPORT, ISC_R_ADDRNOTAVAIL);
			ERROR_MATCH(WSAECONNREFUSED, ISC_R_CONNREFUSED);
			ERROR_MATCH(WSAEHOSTUNREACH, ISC_R_HOSTUNREACH);
			ERROR_MATCH(WSAEHOSTDOWN, ISC_R_HOSTDOWN);
			ERROR_MATCH(WSAENETUNREACH, ISC_R_NETUNREACH);
			ERROR_MATCH(WSAENETDOWN, ISC_R_NETDOWN);
			ERROR_MATCH(WSAENOBUFS, ISC_R_NORESOURCES);
			ERROR_MATCH(WSAECONNRESET, ISC_R_CONNECTIONRESET);
			ERROR_MATCH(WSAECONNABORTED, ISC_R_CONNECTIONRESET);
			ERROR_MATCH(WSAETIMEDOUT, ISC_R_TIMEDOUT);
#undef ERROR_MATCH
		default:
			dev->result = ISC_R_UNEXPECTED;
			isc__strerror(connect_errno, strbuf, sizeof(strbuf));
			UNEXPECTED_ERROR(__FILE__, __LINE__,
					 "internal_connect: connect() %s",
					 strbuf);
		}
	} else {
		dev->result = ISC_R_SUCCESS;
		sock->connected = 1;
		sock->bound = 1;
	}

	sock->connect_ev = NULL;

	UNLOCK(&sock->lock);

	task = dev->ev_sender;
	dev->ev_sender = sock;
	isc_task_sendanddetach(&task, (isc_event_t **)&dev);
}

static void
internal_recv(isc_socket_t *sock, isc_socketevent_t *dev,
	      struct msghdr *messagehdr, int nbytes, int recv_errno)
{
	isc_socketevent_t *ldev;
	int io_state;
	int cc;

	INSIST(VALID_SOCKET(sock));

	LOCK(&sock->lock);
	socket_log(sock, NULL, IOEVENT,
		   isc_msgcat, ISC_MSGSET_SOCKET, ISC_MSG_INTERNALRECV,
		   "internal_recv: task got socket event %p", dev);

	INSIST(sock->pending_recv > 0);
	sock->pending_recv--;
	/* If the event is no longer in the list we can just return */
	ldev = ISC_LIST_HEAD(sock->recv_list);
	while (ldev != NULL && ldev != dev) {
		ldev = ISC_LIST_NEXT(ldev, ev_link);
	}
	if (ldev == NULL)
		goto done;

	/*
	 * Try to do as much I/O as possible on this socket.  There are no
	 * limits here, currently.
	 */
	switch (completeio_recv(sock, dev, messagehdr, nbytes, recv_errno)) {
	case DOIO_SOFT:
		cc = 0;
		recv_errno = 0;
		io_state = startio_recv(sock, dev, &cc, &recv_errno);
		goto done;

	case DOIO_EOF:
		/*
		 * read of 0 means the remote end was closed.
		 * Run through the event queue and dispatch all
		 * the events with an EOF result code.
		 */
		dev->result = ISC_R_EOF;
		send_recvdone_event(sock, &dev);
		goto done;

	case DOIO_SUCCESS:
	case DOIO_HARD:
		send_recvdone_event(sock, &dev);
		break;
	}
 done:
	UNLOCK(&sock->lock);
}

static void
internal_send(isc_socket_t *sock, isc_socketevent_t *dev,
	      struct msghdr *messagehdr, int nbytes, int send_errno)
{
	isc_socketevent_t *ldev;
	int io_state;
	int cc;

	/*
	 * Find out what socket this is and lock it.
	 */
	INSIST(VALID_SOCKET(sock));

	LOCK(&sock->lock);
	socket_log(sock, NULL, IOEVENT,
		   isc_msgcat, ISC_MSGSET_SOCKET, ISC_MSG_INTERNALSEND,
		   "internal_send: task got socket event %p", dev);

	INSIST(sock->pending_send > 0);
	sock->pending_send--;

	/* If the event is no longer in the list we can just return */
	ldev = ISC_LIST_HEAD(sock->send_list);
	while (ldev != NULL && ldev != dev) {
		ldev = ISC_LIST_NEXT(ldev, ev_link);
	}
	if (ldev == NULL)
		goto done;
	/*
	 * Try to do as much I/O as possible on this socket.  There are no
	 * limits here, currently.
	 */
	switch (completeio_send(sock, dev, messagehdr, nbytes, send_errno)) {
	case DOIO_SOFT:
		cc = 0;
		send_errno = 0;
		io_state = startio_send(sock, dev, &cc, &send_errno);
		goto done;

	case DOIO_HARD:
	case DOIO_SUCCESS:
		send_senddone_event(sock, &dev);
		break;
	}


 done:
	UNLOCK(&sock->lock);
}

/*
 * This is the I/O Completion Port Worker Function. It loops forever
 * waiting for I/O to complete and then forwards them for further
 * processing. There are a number of these in separate threads.
 */
static isc_threadresult_t WINAPI
SocketIoThread(LPVOID ThreadContext) {
	isc_socketmgr_t *manager = ThreadContext;
	BOOL bSuccess = FALSE;
	DWORD nbytes;
	IoCompletionInfo *lpo = NULL;
	isc_socket_t *sock = NULL;
	int request;
	isc_socketevent_t *dev = NULL;
	struct msghdr *messagehdr = NULL;
	int errval;
	char strbuf[ISC_STRERRORSIZE];
	int errstatus;

	REQUIRE(VALID_MANAGER(manager));

	/*	Set the thread priority high enough so I/O will
	 *	preempt normal recv packet processing, but not
	 * 	higher than the timer sync thread.
	 */
	if (!SetThreadPriority(GetCurrentThre