myvtm/libtoolkit/bus-unix.c

#include "precompile.h"
#include "bus.h"
#include "sockutil.h"
#include "url.h"
#include "spinlock.h"
#include "list.h"
#include "bus_internal.h"
#include "evtpoll.h"

#include <winpr/file.h>
#include <winpr/pipe.h>
#include <winpr/synch.h>
#include <winpr/string.h>

#include <sys/eventfd.h>

#define TAG TOOLKIT_TAG("bus")

#define BUS_RESULT_DATA		    1				// ==BUS_TYPE_PACKET, callback: callback.on_pkt,  no use
#define BUS_RESULT_INFO	    	    2				// ==BUS_TYPE_INFO, callback: callback.on_inf
#define BUS_RESULT_EVENT  	        3				// ==BUS_TYPE_EVENT, callback: callback.on_evt ,  no use
#define BUS_RESULT_SYSTEM	    4				// ==BUS_TYPE_SYSTEM, callback: callback.on_sys
#define BUS_RESULT_MSG		        5				// send package msg, callback: callback.on_msg
#define BUS_RESULT_UNKNOWN	6

typedef struct msg_t {
	struct list_head entry;
	int type;
	int nparam;
	param_size_t* params;
	HANDLE evt;
	int evt_result;
}msg_t;

struct bus_endpt_t {
	int type;
	int epid;
	union {
		HANDLE pipe_handle;
		SOCKET sock_handle;
	};
	char* url;
	/*define here or iom_t area, this is definitely a problem for now.*/
	evtpoll_t* ep;
	int msg_fd;
	event_epoll_data_t* msg_sem;
	bus_endpt_callback callback;
	struct list_head msg_list;
	spinlock_t msg_lock;
	
	HANDLE tx_evt; //manually
	HANDLE rx_evt; //manually
	OVERLAPPED rx_overlapped;
	int rx_pending;
	int rx_pending_pkt_len;
	int rx_pending_pkt_uc_len;
	iobuffer_queue_t* rx_buf_queue;
	volatile int quit_flag;
};

static void free_msg(msg_t* msg)
{
	free(msg->params);
	free(msg);
}

static __inline int bus_endpoint__data_is_handle(const bus_endpt_t* endpt, void* data)
{
	if ((endpt->type == TYPE_TCP && data == &endpt->sock_handle) ||
		(endpt->type == TYPE_PIPE && data == &endpt->pipe_handle)) {
		return 1;
	}
	return 0;
}

static int to_result(int pkt_type)
{
	switch (pkt_type) {
	case BUS_TYPE_EVENT:
		return BUS_RESULT_EVENT;
	case BUS_TYPE_SYSTEM:
		return BUS_RESULT_SYSTEM;
	case BUS_TYPE_PACKET:
		return BUS_RESULT_DATA;
	case BUS_TYPE_INFO:
		return BUS_RESULT_INFO;
	default:
		break;
	}
	return BUS_RESULT_UNKNOWN;
}

static HANDLE create_pipe_handle(const char* name)
{
	char tmp[MAX_PATH];
	HANDLE pipe = INVALID_HANDLE_VALUE;

	sprintf(tmp, "\\\\.\\pipe\\%s", name);

	for (;;) {
		pipe = CreateFileA(tmp,
			GENERIC_READ | GENERIC_WRITE,
			0,
			NULL,
			OPEN_EXISTING,
			FILE_FLAG_OVERLAPPED,
			NULL);
		if (pipe == INVALID_HANDLE_VALUE) {
			if (GetLastError() == ERROR_PIPE_BUSY) {
				if (WaitNamedPipeA(name, 20000))
					continue;
			}
		}
		break;
	}

	return pipe;
}

static SOCKET create_socket_handle(const char* ip, int port)
{
	SOCKET fd;
	struct sockaddr_in addr;
	/*Warning: only front three param is effective*/
	fd = WSASocketA(AF_INET, SOCK_STREAM, IPPROTO_TCP, NULL, 0, WSA_FLAG_OVERLAPPED);

	if (fd == INVALID_SOCKET) {
		return fd;
	}

	{
		BOOL f = TRUE;
		u_long l = TRUE;
		setsockopt(fd, SOL_SOCKET, SO_DONTLINGER, (char*)&f, sizeof(f));
		/*non block sock*/
		_ioctlsocket(fd, FIONBIO, &l);
	}

	memset(&addr, 0, sizeof(addr));
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = inet_addr(ip);
	WLog_INFO(TAG, "fd(%d) start to connect...", fd);
	if (_connect(fd, (struct sockaddr*) & addr, sizeof(addr)) != 0) {
		if (errno == EINPROGRESS) {
			WLog_WARN(TAG, "in connect progress...");
			fd_set wr_set, ex_set;
			FD_ZERO(&wr_set);
			FD_ZERO(&ex_set);
			FD_SET(fd, &wr_set);
			FD_SET(fd, &ex_set);
			if (_select(fd + 1, NULL, &wr_set, &ex_set, NULL) > 0 && FD_ISSET(fd, &wr_set)) {
				return fd;
			}
		} else {
			WLog_ERR(TAG, "_connect failed : %d", errno);
		}
		closesocket(fd);
		return INVALID_SOCKET;
	}
	WLog_WARN(TAG, "this should be appear hardly!!!");
	return  fd;
}

static int tcp_send_buf(bus_endpt_t* endpt, const char* buf, int n)
{
	DWORD left = n;
	DWORD offset = 0;
	WLog_DBG(TAG, "==> fd(%d): tcp send buf len: %d", endpt->sock_handle, n);
	while (left > 0) {
		BOOL ret;
		WSABUF wsabuf;
		DWORD dwBytesTransfer;
		OVERLAPPED overlapped;
		memset(&overlapped, 0, sizeof(overlapped));
		overlapped.hEvent = endpt->tx_evt;
		ResetEvent(endpt->tx_evt);
		wsabuf.buf = (char*)buf + offset;
		wsabuf.len = left;
		ret = FALSE;
		n = _send(endpt->sock_handle, wsabuf.buf, wsabuf.len, 0);
		if (n == -1) {
			if (errno == EAGAIN || errno == EWOULDBLOCK) {
				fd_set wfds;
				struct timeval tv;
				int retval;
				FD_ZERO(&wfds);
				FD_SET(endpt->sock_handle, &wfds);
				tv.tv_sec = 5;
				tv.tv_usec = 0;
				retval = _select(endpt->sock_handle + 1, NULL, &wfds, NULL, &tv);
				if (retval == -1) {
					WLog_ERR(TAG, "select error, errno: %s", strerror(errno));
				}
				else if (retval && FD_ISSET(endpt->sock_handle, &wfds) > 0) {
					WLog_INFO(TAG, "can write");
					n = _send(endpt->sock_handle, wsabuf.buf, wsabuf.len, 0);
					if (n >= 0) {
						ret = TRUE;
						dwBytesTransfer = n;
					}
				} else {
					WLog_WARN(TAG, "write timeout");
					ret = TRUE;
					dwBytesTransfer = 0;
				}
			}
			else {
				WLog_ERR(TAG, "_send failed: %s", strerror(errno));
			}
		}
		else {
			ret = TRUE;
			dwBytesTransfer = n;
		}
		if (ret && dwBytesTransfer) {
			offset += dwBytesTransfer;
			left -= dwBytesTransfer;
		}
		else {
			WLog_DBG(TAG, "<== error fd(%d): tcp send buf left: %d", endpt->sock_handle, left);
			return -1;
		}
	}
	WLog_DBG(TAG, "<== fd(%d): tcp send buf len: %d", endpt->sock_handle, n);
	return 0;
}

static int pipe_send_buf(bus_endpt_t* endpt, const char* buf, int n)
{
	DWORD left = n;
	DWORD offset = 0;

	while (left > 0) {
		BOOL ret;
		DWORD dwBytesTransfer;
		OVERLAPPED overlapped;
		memset(&overlapped, 0, sizeof(overlapped));
		overlapped.hEvent = endpt->tx_evt;
		ResetEvent(endpt->tx_evt);
		ret = WriteFile(endpt->pipe_handle, buf + offset, left, &dwBytesTransfer, &overlapped);
		if (!ret && GetLastError() == ERROR_IO_PENDING) {
			ret = GetOverlappedResult(endpt->pipe_handle, &overlapped, &dwBytesTransfer, TRUE);
		}
		if (ret && dwBytesTransfer) {
			offset += dwBytesTransfer;
			left -= dwBytesTransfer;
		}
		else {
			return -1;
		}
	}

	return 0;
}

static int send_buf(bus_endpt_t* endpt, const char* buf, int n)
{
	if (endpt->type == TYPE_PIPE) {
		return pipe_send_buf(endpt, buf, n);
	}
	else if (endpt->type == TYPE_TCP) {
		return tcp_send_buf(endpt, buf, n);
	}
	else {
		return -1;
	}
}

static int send_pkt_raw(bus_endpt_t* endpt, iobuffer_t* pkt)
{
	int pkt_len = iobuffer_get_length(pkt);
	int rc;

	iobuffer_write_head(pkt, IOBUF_T_I4, &pkt_len, 0);
	rc = send_buf(endpt, iobuffer_data(pkt, 0), iobuffer_get_length(pkt));

	return rc;
}

static int pipe_recv_buf(bus_endpt_t* endpt, char* buf, DWORD n)
{
	DWORD left = n;
	DWORD offset = 0;

	while (left > 0) {
		BOOL ret;
		DWORD dwBytesTransfer;
		OVERLAPPED overlapped;
		memset(&overlapped, 0, sizeof(overlapped));
		overlapped.hEvent = endpt->rx_evt;
		ResetEvent(overlapped.hEvent);
		ret = ReadFile(endpt->pipe_handle, buf + offset, left, &dwBytesTransfer, &overlapped);
		if (!ret && GetLastError() == ERROR_IO_PENDING) {
			ret = GetOverlappedResult(endpt->pipe_handle, &overlapped, &dwBytesTransfer, TRUE);
		}
		if (ret && dwBytesTransfer) {
			offset += dwBytesTransfer;
			left -= dwBytesTransfer;
		}
		else {
			return -1;
		}
	}

	return 0;
}

static int tcp_recv_buf(bus_endpt_t* endpt, char* buf, DWORD n)
{
	DWORD left = n;
	DWORD offset = 0;
	WLog_DBG(TAG, "==> fd(%d): tcp recv buf len: %d", endpt->sock_handle, n);
	while (left > 0) {
		BOOL ret;
		DWORD dwBytesTransfer;
		ret = FALSE;
		n = _recv(endpt->sock_handle, buf + offset, left, 0);
		if (n == -1) {
			if (errno == EAGAIN || errno == EWOULDBLOCK) {
				fd_set rfds;
				struct timeval tv;
				int retval;
				FD_ZERO(&rfds);
				FD_SET(endpt->sock_handle, &rfds);
				tv.tv_sec = 5;
				tv.tv_usec = 0;
				retval = _select(endpt->sock_handle + 1, &rfds, NULL, NULL, &tv);
				if (retval == -1) {
					WLog_ERR(TAG, "select failed: %s", strerror(errno));
				}
				else if (retval && FD_ISSET(endpt->sock_handle, &rfds) > 0) {
					WLog_INFO(TAG, "can read");
					n = _recv(endpt->sock_handle, buf + offset, left, 0);
					if (n >= 0) {
						ret = TRUE;
						dwBytesTransfer = n;
					}
				}
				else {
					WLog_WARN(TAG, "read timeout: %d, left: %d", retval, left);
					ret = TRUE;
					dwBytesTransfer = 0;
				}
			}
		}
		else {
			ret = TRUE;
			dwBytesTransfer = n;
		}

		if (ret && dwBytesTransfer) {
			offset += dwBytesTransfer;
			left -= dwBytesTransfer;
		}
		else if (!ret) {
			return -1;
		}
	}
	WLog_DBG(TAG, "<== fd(%d): tcp recv buf len: %d", endpt->sock_handle, n);
	return 0;
}

/*read data block, n is the dream length of data to read which will store in buf*/
static int recv_buf(bus_endpt_t* endpt, char* buf, DWORD n)
{
	if (endpt->type == TYPE_PIPE) {
		return pipe_recv_buf(endpt, buf, n);
	}
	else if (endpt->type == TYPE_TCP) {
		return tcp_recv_buf(endpt, buf, n);
	}
	else {
		return -1;
	}
}

static int recv_pkt_raw(bus_endpt_t* endpt, iobuffer_t** pkt)
{
	int pkt_len;
	int rc = -1;

	rc = recv_buf(endpt, (char*)&pkt_len, 4);
	if (rc != 0)
		return rc;
	*pkt = iobuffer_create(-1, pkt_len);
	iobuffer_push_count(*pkt, pkt_len);
	if (pkt_len > 0) {
		rc = recv_buf(endpt, iobuffer_data(*pkt, 0), pkt_len);
	}
	if (rc < 0) {
		iobuffer_destroy(*pkt);
		*pkt = NULL;
	}

	return rc;
}

static int start_read_pkt(bus_endpt_t* endpt, iobuffer_t** p_pkt)
{
	DWORD dwBytesTransferred;
	BOOL ret;
	int rc = 0;
	iobuffer_t* pkt = NULL;

	*p_pkt = NULL;
	WLog_DBG(TAG, "==>endpt(%d): start_read_pkt", endpt->epid);
	ResetEvent(endpt->rx_evt);
	WLog_DBG(TAG, "ResetEvent(endpt->rx_evt) ???");
	endpt->rx_pending_pkt_uc_len = 0;

	if (endpt->type == TYPE_PIPE) {
		ret = ReadFile(endpt->pipe_handle,
			&endpt->rx_pending_pkt_len,
			4,
			&dwBytesTransferred,
			&endpt->rx_overlapped);
	}
	else if (endpt->type == TYPE_TCP) {
		do {
			WLog_DBG(TAG, "_recv ???");
			ret = _recv(endpt->sock_handle, (char*)&endpt->rx_pending_pkt_len, 4, 0);

		} while (ret < 0 && errno == EINTR);
		WLog_DBG(TAG, "_recv return: %d, %d", ret, errno);
	}
	else {
		WLog_ERR(TAG, "<== endpt(%d): start_read_pkt unkonwn type", endpt->epid);
		return -1;
	}
	if (ret >= 0) {
		dwBytesTransferred = ret;
		endpt->rx_pending_pkt_uc_len = ret;
		if (dwBytesTransferred == 0) {
			WLog_ERR(TAG, "<== endpt(%d): start_read_pkt dwBytesTransferred is error.", endpt->epid);
			return -1;
		}
		if (dwBytesTransferred < 4) {
			WLog_DBG(TAG, "endpt(%d): receive buffer less than dream len", endpt->epid);
			rc = recv_buf(endpt, (char*)&endpt->rx_pending_pkt_len + dwBytesTransferred, 4 - dwBytesTransferred);
			if (rc < 0) {
				WLog_ERR(TAG, "<== endpt(%d): start_read_pkt recv_buf error.", endpt->epid);
				return rc;
			}
		}
		WLog_DBG(TAG, "iobuffer_create ???");
		pkt = iobuffer_create(0, endpt->rx_pending_pkt_len);
		endpt->rx_pending_pkt_uc_len = 0;
		if (endpt->rx_pending_pkt_len > 0) {
			WLog_DBG(TAG, "endpt->rx_pending_pkt_len > 0 ???");
			rc = recv_buf(endpt, iobuffer_data(pkt, 0), endpt->rx_pending_pkt_len);
			if (rc < 0) {
				WLog_DBG(TAG, "iobuffer_destroy ???");
				iobuffer_destroy(pkt);
				WLog_ERR(TAG, "<== endpt(%d): start_read_pkt recv_buf error.", endpt->epid);
				return rc;
			}
			WLog_DBG(TAG, "iobuffer_push_count ???");
			iobuffer_push_count(pkt, endpt->rx_pending_pkt_len);
		}
		WLog_DBG(TAG, "*p_pkt = pkt ???");
		*p_pkt = pkt;
		WLog_ERR(TAG, "<== endpt(%d): start_read_pkt recv_buf succ.", endpt->epid);
		return 0;
	}
	else if(errno == EAGAIN || errno == EWOULDBLOCK) {
		WLog_DBG(TAG, "endpt(%d): set rx pending flag.", endpt->epid);
		endpt->rx_pending = 1;
		return 0;
	}
	WLog_ERR(TAG, "<== endpt(%d): start_read_pkt recv_buf failed.", endpt->epid);
	return -1;
}

static int read_left_pkt(bus_endpt_t* endpt, iobuffer_t** p_pkt)
{
	BOOL ret;
	int rc;
	DWORD dwBytesTransferred;
	iobuffer_t* pkt = NULL;
	WLog_DBG(TAG, "==> fd(%d): read left pkt", endpt->sock_handle);
	if (endpt->type == TYPE_PIPE) {
		ret = GetOverlappedResult(endpt->pipe_handle, &endpt->rx_overlapped, &dwBytesTransferred, TRUE);
	}
	else if (endpt->type == TYPE_TCP) {
		do 
		{
			ret = _recv(endpt->sock_handle,
				(char*)&endpt->rx_pending_pkt_len + endpt->rx_pending_pkt_uc_len,
				4 - endpt->rx_pending_pkt_uc_len, 0);
		} while (ret == -1 && errno == EINTR);
	}
	if (ret < 0) {
		WLog_ERR(TAG, "<== fd(%d): read left pkt failed: ret %d, err: %s", endpt->sock_handle, ret, strerror(errno));
		return -1;
	}
	else if(ret == 0) {
		WLog_WARN(TAG, "<== fd(%d): peer socket close.", endpt->sock_handle);
	}

	if (dwBytesTransferred < 4) {
		rc = recv_buf(endpt, (char*)&endpt->rx_pending_pkt_len + dwBytesTransferred, 4 - dwBytesTransferred);
		if (rc < 0)
			return rc;
	}
	/*the first 4 bytes indicates the length of content and then read the buffer content.*/
	pkt = iobuffer_create(-1, endpt->rx_pending_pkt_len);
	WLog_DBG(TAG, "after read pkt len, start to read pkt's content: %d", endpt->rx_pending_pkt_len);
	rc = recv_buf(endpt, iobuffer_data(pkt, 0), endpt->rx_pending_pkt_len);
	if (rc < 0) {
		iobuffer_destroy(pkt);
		return rc;
	}

	iobuffer_push_count(pkt, endpt->rx_pending_pkt_len);
	*p_pkt = pkt;
	WLog_DBG(TAG, "endpt(%d): reset rx_pending and return!", endpt->epid);
	endpt->rx_pending = 0;
	return 0;
}

static int append_rx_pkt(bus_endpt_t* endpt, iobuffer_t* pkt)
{
	int type;
	int read_state;

	read_state = iobuffer_get_read_state(pkt);
	iobuffer_read(pkt, IOBUF_T_I4, &type, 0);
	iobuffer_restore_read_state(pkt, read_state);
	if (type == BUS_TYPE_PACKET || type == BUS_TYPE_INFO || type == BUS_TYPE_EVENT || type == BUS_TYPE_SYSTEM) {
		iobuffer_queue_enqueue(endpt->rx_buf_queue, pkt);
		WLog_DBG(TAG, "<== append_rx_pkt finished");
		return 1;
	}
	else {
		WLog_DBG(TAG, "<== append_rx_pkt failed!");
		return -1;
	}
}

TOOLKIT_API int bus_endpt_create(const char* url, int epid, const bus_endpt_callback* callback, bus_endpt_t** p_endpt)
{
	bus_endpt_t* endpt = NULL;
	char* tmp_url;
	url_fields uf;
	int rc;
	int v;
	iobuffer_t* buf = NULL;
	iobuffer_t* ans_buf = NULL;

	if (!url)
		return -1;

	tmp_url = _strdup(url);

	if (url_parse(tmp_url, &uf) < 0) {
		free(tmp_url);
		return -1;
	}

	endpt = ZALLOC_T(bus_endpt_t);
	endpt->sock_handle = -1;
	endpt->msg_fd = -1;
	endpt->ep = NULL;
	endpt->url = tmp_url;

	if (_stricmp(uf.scheme, "tcp") == 0) {
		endpt->type = TYPE_TCP;
		endpt->sock_handle = create_socket_handle(uf.host, uf.port);
		if (endpt->sock_handle == INVALID_SOCKET)
			goto on_error;
		WLog_INFO(TAG, "bus endpt socket fd: %d", endpt->sock_handle);
	}
	else if (_stricmp(uf.scheme, "pipe") == 0) {
		endpt->type = TYPE_PIPE;
		endpt->pipe_handle = create_pipe_handle(uf.host);
		if (endpt->pipe_handle == INVALID_HANDLE_VALUE)
			goto on_error;
		WLog_INFO(TAG, "bus endpt pipe fd: %d", endpt->sock_handle);
	}
	else {
		goto on_error;
	}

	endpt->ep = evtpoll_create();
	if (!endpt->ep) {
		WLog_ERR(TAG, "evtpoll create failed!");
		goto on_error;
	}

	endpt->epid = epid;
	endpt->tx_evt = CreateEventA(NULL, TRUE, FALSE, NULL);
	endpt->rx_evt = CreateEventA(NULL, TRUE, FALSE, NULL);
	endpt->rx_buf_queue = iobuffer_queue_create();
	endpt->msg_fd = eventfd(0, EFD_CLOEXEC | EFD_SEMAPHORE);
	if (endpt->msg_fd == -1) {
		WLog_ERR(TAG, "create event fd failed: %s(%d)", strerror(errno), errno);
		goto on_error;
	}

	INIT_LIST_HEAD(&endpt->msg_list);
	spinlock_init(&endpt->msg_lock);
	memcpy(&endpt->callback, callback, sizeof(bus_endpt_callback));

	buf = iobuffer_create(-1, -1);
	v = BUS_TYPE_ENDPT_REGISTER;
	iobuffer_write(buf, IOBUF_T_I4, &v, 0);
	v = endpt->epid;
	iobuffer_write(buf, IOBUF_T_I4, &v, 0);
	WLog_DBG(TAG, "start to send_pkt_raw");
	rc = send_pkt_raw(endpt, buf);
	WLog_INFO(TAG, "send_pkt_raw return %d", rc);
	if (rc != 0)
		goto on_error;
	rc = recv_pkt_raw(endpt, &ans_buf);
	WLog_INFO(TAG, "recv_pkt_raw return %d", rc);
	if (rc != 0) {
		goto on_error;
	}
	iobuffer_read(ans_buf, IOBUF_T_I4, &v, 0);
	iobuffer_read(ans_buf, IOBUF_T_I4, &rc, 0);
	if (rc != 0)
		goto on_error;

	url_free_fields(&uf);
	if (buf)
		iobuffer_destroy(buf);
	if (ans_buf)
		iobuffer_destroy(ans_buf);

	if (-1 == evtpoll_attach(endpt->ep, endpt->msg_fd)) {
		goto on_error;
	}
	if (evtpoll_subscribe(endpt->ep, EV_READ, endpt->msg_fd, &endpt->msg_fd, NULL)) {
		WLog_ERR(TAG, "epoll subscribe bus endpt eventfd failed.");
		goto on_error_msg;
	}

	/* subscribe read event [3/27/2020 Gifur] */
	if (evtpoll_attach(endpt->ep, endpt->sock_handle)) {
		WLog_ERR(TAG, "epoll attch bus endpt failed.");
		goto on_error_msg;
	}
	if (evtpoll_subscribe(endpt->ep, EV_READ, endpt->sock_handle, &endpt->sock_handle, NULL)) {
		WLog_ERR(TAG, "epoll subscribe bus endpt failed.");
		goto on_error_handle;
	}
	*p_endpt = endpt;
	return 0;

on_error_handle:
	evtpoll_detach(endpt->ep, endpt->sock_handle);
on_error_msg:
	evtpoll_detach(endpt->ep, endpt->msg_fd);
on_error:
	if (endpt->type == TYPE_TCP) {
		closesocket(endpt->sock_handle);
	}
	else if (endpt->type == TYPE_PIPE) {
		CloseHandle(endpt->pipe_handle);
	}
	if (endpt->msg_fd > 0)
		close(endpt->msg_fd);
	if (endpt->tx_evt)
		CloseHandle(endpt->tx_evt);
	if (endpt->rx_evt)
		CloseHandle(endpt->rx_evt);
	if (endpt->rx_buf_queue)
		iobuffer_queue_destroy(endpt->rx_buf_queue);
	if (endpt->url)
		free(endpt->url);
	free(endpt);
	url_free_fields(&uf);
	if (buf)
		iobuffer_destroy(buf);
	if (ans_buf)
		iobuffer_destroy(ans_buf);
	if (endpt->ep != NULL) {
		evtpoll_destroy(endpt->ep);
	}
	return -1;
}

TOOLKIT_API void bus_endpt_destroy(bus_endpt_t* endpt)
{
	int rc = -1;
	iobuffer_t* buf = NULL;
	iobuffer_t* ans_buf = NULL;
	int v;

	assert(endpt);

	buf = iobuffer_create(-1, -1);
	v = BUS_TYPE_ENDPT_UNREGISTER;
	iobuffer_write(buf, IOBUF_T_I4, &v, 0);
	v = endpt->epid;
	iobuffer_write(buf, IOBUF_T_I4, &v, 0);
	rc = send_pkt_raw(endpt, buf);
	if (rc != 0)
		goto on_error;
	rc = recv_pkt_raw(endpt, &ans_buf);
	if (rc != 0)
		goto on_error;
	iobuffer_read(ans_buf, IOBUF_T_I4, &v, 0);
	iobuffer_read(ans_buf, IOBUF_T_I4, &rc, 0);
	{
		msg_t* msg, * t;
		list_for_each_entry_safe(msg, t, &endpt->msg_list, msg_t, entry) {
			list_del(&msg->entry);
			if (msg->evt)
				CloseHandle(msg->evt);
			free(msg);
		}
	}

on_error:

	if (buf)
		iobuffer_destroy(buf);
	if (ans_buf)
		iobuffer_destroy(ans_buf);
	if (endpt->type == TYPE_TCP) {
		closesocket(endpt->sock_handle);
	}
	else if (endpt->type == TYPE_PIPE) {
		CloseHandle(endpt->pipe_handle);
	}
	if (endpt->msg_fd)
		close(endpt->msg_fd);
	if (endpt->tx_evt)
		CloseHandle(endpt->tx_evt);
	if (endpt->rx_evt)
		CloseHandle(endpt->rx_evt);
	if (endpt->rx_buf_queue)
		iobuffer_queue_destroy(endpt->rx_buf_queue);

	assert(endpt->ep);
	evtpoll_destroy(endpt->ep);

	if (endpt->url)
		free(endpt->url);
	free(endpt);
}

// 1 : recv ok
// 0 : time out
// <0 : error
static int bus_endpt_poll_internal(bus_endpt_t* endpt, int* result, int timeout)
{
	iobuffer_t* pkt = NULL;
	int rc;
	BOOL ret;

	assert(endpt);

	// peek first packge type
	if (iobuffer_queue_count(endpt->rx_buf_queue) > 0) {
		pkt = iobuffer_queue_head(endpt->rx_buf_queue);
	}
	else {
		// no received package, try to receive one
		if (!endpt->rx_pending) {
			rc = start_read_pkt(endpt, &pkt);
			if (rc < 0) {
				WLog_ERR(TAG, "start read pkt failed.");
				return rc;
			}
			if (pkt) {
				WLog_INFO(TAG, "pkt has read");
				rc = append_rx_pkt(endpt, pkt); // append pkt to rx_buf_queue
				if (rc < 0) {
					iobuffer_destroy(pkt);
					return -1;
				}
			}
		}
		else {
			//WLog_ERR(TAG, "is pending now.");
		}
		// if receive is pending, wait for send or receive complete event
		if (!pkt) {
			//WLog_DBG(TAG, "wait msg sem or received event. tiemout: %d", timeout);
			{
				int nfds;
				int ret;
				int i;
				struct epoll_event events[MAX_EPOLL_EVENT];
				struct epoll_event* pe;
				nfds = evtpoll_wait(endpt->ep, events, MAX_EPOLL_EVENT, timeout);
				if (nfds == 0) {
					//WLog_DBG(TAG, "epoll wait timeout.");
					return 0; //timeout
				}
				if (nfds == -1) {
					return -1;
				}
				WLog_DBG(TAG, "epoll wait return nfd: %d", nfds);
				for (i = 0; i < nfds; ++i) {
					void* pdata = NULL;
					pe = events + i;
					WLog_INFO(TAG, "loop events[%d]::fd(0x%08X) OUT:%d, IN:%d", i, pe->data.fd,
						pe->events & EPOLLOUT ? 1 : 0, pe->events & EPOLLIN ? 1 : 0);
					assert(pe->events & EPOLLIN);
					ret = evtpoll_deal(endpt->ep, pe, &pdata, 0);
					if (!ret) {
						assert(pdata);
						if(bus_endpoint__data_is_handle(endpt, pdata))
						{
							rc = read_left_pkt(endpt, &pkt);
							if (rc < 0)
								return rc;
							if (pkt) {
								rc = append_rx_pkt(endpt, pkt);
								if (rc < 0) {
									iobuffer_destroy(pkt);
									return -1;
								}
							}
						}
						else if (pdata == &endpt->msg_fd) {
							uint64_t rdata;
							WLog_DBG(TAG, "message arrive.");
							do 
							{
								ret = read(endpt->msg_fd, &rdata, sizeof rdata);
							} while (ret < 0 && errno == EINTR);

							if (ret < 0) {
								WLog_ERR(TAG, "read msg fd failed: %s", strerror(errno));
								abort();
							}
							*result = BUS_RESULT_MSG;
							return 1;
						}
					}
				}
			}
		}
		else {
			WLog_ERR(TAG, "pkt has readed");
		}
	}

	if (pkt) {
		int type;
		int read_state = iobuffer_get_read_state(pkt);
		iobuffer_read(pkt, IOBUF_T_I4, &type, 0);
		iobuffer_restore_read_state(pkt, read_state);
		*result = to_result(type);
		if (*result == BUS_RESULT_UNKNOWN) {
			WLog_ERR(TAG, "bug: unknown pkt type!");
			return -1;
		}
		return 1;
	}
	return -1;
}

static int recv_until(bus_endpt_t* endpt, int type, iobuffer_t** p_ansbuf)
{
	int rc;
	iobuffer_t* ans_pkt = NULL;
	int ans_type;
	WLog_DBG(TAG, "==>endpt(%d): recv until type: 0x%08X", endpt->epid, type);
	for (;;) {
		if (!endpt->rx_pending) {
			rc = start_read_pkt(endpt, &ans_pkt);
			if (rc < 0) {
				break;
			}
		} else {
			WLog_DBG(TAG, "endpt(%d) is pending", endpt->epid);
		}
		if (!ans_pkt) {
			int nfds;
			int ret;
			int i, flag = 0;
			struct epoll_event events[MAX_EPOLL_EVENT];
			struct epoll_event* pe;
			nfds = evtpoll_wait(endpt->ep, events, MAX_EPOLL_EVENT, -1);
			if (nfds == 0) {
				continue;
			}
			if (nfds == -1) {
				return -1;
			}
			WLog_DBG(TAG, "epoll wait return nfd: %d", nfds);
			for (i = 0; i < nfds; ++i) {
				void* pdata = NULL;
				pe = events + i;
				ret = evtpoll_deal(endpt->ep, pe, &pdata, 0);
				if (!ret && bus_endpoint__data_is_handle(endpt, pdata)) {
					flag = 1;
					break;
				}
			}
			if (flag) {
				rc = read_left_pkt(endpt, &ans_pkt);
				if (rc < 0) {
					break;
				}
			}
		}
		if (ans_pkt) {
			int read_state = iobuffer_get_read_state(ans_pkt);
			iobuffer_read(ans_pkt, IOBUF_T_I4, &ans_type, 0);
			iobuffer_restore_read_state(ans_pkt, read_state);
			if (ans_type == type) {
				*p_ansbuf = ans_pkt;
				break;
			}
			else {
				rc = append_rx_pkt(endpt, ans_pkt);
				if (rc < 0) {
					iobuffer_destroy(ans_pkt);
					break;
				}
				else {
					ans_pkt = NULL;
				}
			}
		}
	}
	return rc;
}

static int recv_until_result(bus_endpt_t* endpt, int* p_result)
{
	int rc;
	iobuffer_t* ans_pkt = NULL;
	int type, error;

	rc = recv_until(endpt, BUS_TYPE_ERROR, &ans_pkt);
	if (rc < 0)
		return rc;

	iobuffer_read(ans_pkt, IOBUF_T_I4, &type, 0);
	iobuffer_read(ans_pkt, IOBUF_T_I4, &error, 0);
	iobuffer_destroy(ans_pkt);

	*p_result = error;

	return rc;
}

static int recv_until_state(bus_endpt_t* endpt, int* p_state)
{
	int rc;
	iobuffer_t* ans_pkt = NULL;
	int type, epid, state;

	rc = recv_until(endpt, BUS_TYPE_ENDPT_GET_STATE, &ans_pkt);
	if (rc < 0)
		return rc;
	iobuffer_read(ans_pkt, IOBUF_T_I4, &type, 0);
	iobuffer_read(ans_pkt, IOBUF_T_I4, &epid, 0);
	iobuffer_read(ans_pkt, IOBUF_T_I4, &state, 0);
	iobuffer_destroy(ans_pkt);
	WLog_DBG(TAG, "state address: 0x%08X", p_state);
	*p_state = state;
	return rc;
}

TOOLKIT_API int bus_endpt_send_pkt(bus_endpt_t* endpt, int epid, int type, iobuffer_t* pkt)
{
	int t;
	int rc;
	int read_state;
	int write_state;
	int error;

	assert(endpt);

	read_state = iobuffer_get_read_state(pkt);
	write_state = iobuffer_get_write_state(pkt);

	t = epid; // remote epid
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = endpt->epid; // local epid
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = type; // user type
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = BUS_TYPE_PACKET; // type
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);

	rc = send_pkt_raw(endpt, pkt);

	iobuffer_restore_read_state(pkt, read_state);
	iobuffer_restore_write_state(pkt, write_state);

	if (rc < 0)
		return rc;

	rc = recv_until_result(endpt, &error);

	if (rc == 0 && error != 0)
		rc = error;

	return rc;
}

TOOLKIT_API int bus_endpt_send_info(bus_endpt_t* endpt, int epid, int type, iobuffer_t* pkt)
{
	int t;
	int rc;
	int read_state;
	int write_state;

	assert(endpt);
	WLog_DBG(TAG, "==> endpt(%d) send info: %d, 0x%08X.", endpt->epid, epid, type);
	read_state = iobuffer_get_read_state(pkt);
	write_state = iobuffer_get_write_state(pkt);

	t = epid; // remote epid
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = endpt->epid; // local epid
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = type; // user type
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = BUS_TYPE_INFO; // type
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);

	rc = send_pkt_raw(endpt, pkt);

	iobuffer_restore_read_state(pkt, read_state);
	iobuffer_restore_write_state(pkt, write_state);

	return rc;
}

TOOLKIT_API int bus_endpt_bcast_evt(bus_endpt_t* endpt, int type, iobuffer_t* pkt)
{
	int t;
	int rc;
	int read_state;
	int write_state;

	assert(endpt);

	read_state = iobuffer_get_read_state(pkt);
	write_state = iobuffer_get_write_state(pkt);

	t = endpt->epid;
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = type;
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);
	t = BUS_TYPE_EVENT;
	iobuffer_write_head(pkt, IOBUF_T_I4, &t, 0);

	rc = send_pkt_raw(endpt, pkt);

	iobuffer_restore_read_state(pkt, read_state);
	iobuffer_restore_write_state(pkt, write_state);

	return rc;
}

static int bus_endpt_recv_pkt(bus_endpt_t* endpt, int* p_epid, int* p_type, iobuffer_t** p_pkt)
{
	if (iobuffer_queue_count(endpt->rx_buf_queue) > 0) {
		iobuffer_t* pkt = iobuffer_queue_head(endpt->rx_buf_queue);
		int read_state = iobuffer_get_read_state(pkt);
		int pkt_type, usr_type, from_epid, to_epid;
		iobuffer_read(pkt, IOBUF_T_I4, &pkt_type, 0);
		if (pkt_type == BUS_TYPE_PACKET || pkt_type == BUS_TYPE_INFO) {
			iobuffer_read(pkt, IOBUF_T_I4, &usr_type, 0);
			iobuffer_read(pkt, IOBUF_T_I4, &from_epid, 0);
			iobuffer_read(pkt, IOBUF_T_I4, &to_epid, 0);
			if (p_epid)
				*p_epid = from_epid;
			if (p_type)
				*p_type = usr_type;
			iobuffer_queue_deque(endpt->rx_buf_queue);
			if (p_pkt) {
				*p_pkt = pkt;
			}
			else {
				iobuffer_destroy(pkt);
			}
			return 0;
		}
		else {
			iobuffer_restore_read_state(pkt, read_state);
		}
	}
	return -1;
}

static int bus_endpt_recv_evt(bus_endpt_t* endpt, int* p_epid, int* p_type, iobuffer_t** p_pkt)
{
	if (iobuffer_queue_count(endpt->rx_buf_queue) > 0) {
		iobuffer_t* pkt = iobuffer_queue_head(endpt->rx_buf_queue);
		int read_state = iobuffer_get_read_state(pkt);
		int pkt_type, usr_type, from_epid;
		iobuffer_read(pkt, IOBUF_T_I4, &pkt_type, 0);
		if (pkt_type == BUS_TYPE_EVENT) {
			iobuffer_read(pkt, IOBUF_T_I4, &usr_type, 0);
			iobuffer_read(pkt, IOBUF_T_I4, &from_epid, 0);
			if (p_epid)
				*p_epid = from_epid;
			if (p_type)
				*p_type = usr_type;
			iobuffer_queue_deque(endpt->rx_buf_queue);
			if (p_pkt) {
				*p_pkt = pkt;
			}
			else {
				iobuffer_destroy(pkt);
			}
			return 0;
		}
		else {
			iobuffer_restore_read_state(pkt, read_state);
		}
	}
	return -1;
}

static int bus_endpt_recv_sys(bus_endpt_t* endpt, int* p_epid, int* p_state)
{
	if (iobuffer_queue_count(endpt->rx_buf_queue) > 0) {
		iobuffer_t* pkt = iobuffer_queue_head(endpt->rx_buf_queue);
		int read_state = iobuffer_get_read_state(pkt);
		int pkt_type, epid, state;
		iobuffer_read(pkt, IOBUF_T_I4, &pkt_type, 0);
		if (pkt_type == BUS_TYPE_SYSTEM) {
			iobuffer_read(pkt, IOBUF_T_I4, &epid, 0);
			iobuffer_read(pkt, IOBUF_T_I4, &state, 0);
			if (p_epid)
				*p_epid = epid;
			if (p_state)
				*p_state = state;
			iobuffer_queue_deque(endpt->rx_buf_queue);
			iobuffer_destroy(pkt);
			return 0;
		}
		else {
			iobuffer_restore_read_state(pkt, read_state);
		}
	}
	return -1;
}

static int bus_endpt_recv_msg(bus_endpt_t* endpt, msg_t** p_msg)
{
	int rc = -1;

	assert(endpt);
	assert(p_msg);

	spinlock_enter(&endpt->msg_lock, -1);
	if (!list_empty(&endpt->msg_list)) {
		msg_t* e = list_first_entry(&endpt->msg_list, msg_t, entry);
		list_del(&e->entry);
		rc = 0;
		*p_msg = e;
	}
	spinlock_leave(&endpt->msg_lock);

	return rc;
}

TOOLKIT_API int bus_endpt_get_state(bus_endpt_t* endpt, int epid, int* p_state)
{
	iobuffer_t* buf = NULL;
	int v;
	int rc = -1;

	assert(endpt);

	buf = iobuffer_create(-1, -1);
	v = BUS_TYPE_ENDPT_GET_STATE;
	iobuffer_write(buf, IOBUF_T_I4, &v, 0);
	v = epid;
	iobuffer_write(buf, IOBUF_T_I4, &v, 0);

	rc = send_pkt_raw(endpt, buf);
	if (rc < 0) {
		WLog_ERR(TAG, "send pkt raw failed.");
		goto on_error;
	}
	rc = recv_until_state(endpt, p_state);

on_error:

	if (buf)
		iobuffer_destroy(buf);

	return rc;
}

TOOLKIT_API int bus_endpt_post_msg(bus_endpt_t* endpt, int msg, int nparam, param_size_t params[])
{
	msg_t* e;
	int rc;
	uint64_t wdata = 0;
	assert(endpt);
	WLog_DBG(TAG, "==> endpt(%d) post msg: %d", endpt->epid, msg);
	e = MALLOC_T(msg_t);
	e->type = msg;
	e->nparam = nparam;
	if (nparam) {
		e->params = (param_size_t*)malloc(sizeof(param_size_t) * nparam);
		memcpy(e->params, params, sizeof(param_size_t) * nparam);
	}
	else {
		e->params = NULL;
	}
	e->evt = NULL;
	spinlock_enter(&endpt->msg_lock, -1);
	list_add_tail(&e->entry, &endpt->msg_list);
	spinlock_leave(&endpt->msg_lock);
	wdata = 1;
	rc = write(endpt->msg_fd, &wdata, sizeof wdata);
	if (rc == -1) {
		WLog_ERR(TAG, "write to eventfd failed: %s(%d)", strerror(errno), errno);
		return -1;
	}
	return 0;
}

TOOLKIT_API int bus_endpt_send_msg(bus_endpt_t* endpt, int msg, int nparam, param_size_t params[])
{
	msg_t e;
	int rc;
	uint64_t wdata = 0;
	assert(endpt);
	WLog_DBG(TAG, "==> endpt(%d) send msg: epid %d, param counts %d", endpt->epid, msg, nparam);
	e.type = msg;
	e.nparam = nparam;
	if (nparam) {
		e.params = (param_size_t*)malloc(sizeof(param_size_t) * nparam);
		memcpy(e.params, params, sizeof(param_size_t) * nparam);
	}
	else {
		e.params = NULL;
	}
	e.evt_result = 0;
	e.evt = CreateEventA(NULL, TRUE, FALSE, NULL);
	assert(e.evt != NULL);
	spinlock_enter(&endpt->msg_lock, -1);
	list_add_tail(&e.entry, &endpt->msg_list);
	spinlock_leave(&endpt->msg_lock);
	wdata = 1;
	rc = write(endpt->msg_fd, &wdata, sizeof wdata);
	if (rc == -1) {
		WLog_ERR(TAG, "write to eventfd failed: %s(%d)", strerror(errno), errno);
		CloseHandle(e.evt);
		if (nparam) {
			free(e.params);
		}
		WLog_DBG(TAG, "<== error endpt(%d) send msg: %d", endpt->epid, msg);
		return -1;
	}
	WaitForSingleObject(e.evt, INFINITE);
	CloseHandle(e.evt);

	if (nparam) {
		free(e.params);
	}
	WLog_DBG(TAG, "<== endpt(%d) send msg: epid %d, evt_res: %d", endpt->epid, msg, e.evt_result);
	return e.evt_result;
}

TOOLKIT_API int bus_endpt_get_epid(bus_endpt_t* endpt)
{
	return endpt->epid;
}

TOOLKIT_API const char* bus_endpt_get_url(bus_endpt_t* endpt)
{
	return endpt->url;
}

TOOLKIT_API int bus_endpt_poll(bus_endpt_t* endpt, int timeout)
{
	int result;
	int rc;
	int epid, type, state;
	iobuffer_t* pkt = NULL;

	rc = bus_endpt_poll_internal(endpt, &result, timeout);
	//WLog_DBG(TAG, "bus endpt poll internal: %d, %d", rc, result);
	if (rc > 0) {
		if (result == BUS_RESULT_DATA) {
			bus_endpt_recv_pkt(endpt, &epid, &type, &pkt);
			if (endpt->callback.on_pkt)
				endpt->callback.on_pkt(endpt, epid, type, &pkt, endpt->callback.user_data);
			if (pkt)
				iobuffer_dec_ref(pkt);
		}
		else if (result == BUS_RESULT_INFO) {
			bus_endpt_recv_pkt(endpt, &epid, &type, &pkt);
			if (endpt->callback.on_inf)
				endpt->callback.on_inf(endpt, epid, type, &pkt, endpt->callback.user_data);
			if (pkt)
				iobuffer_dec_ref(pkt);
		}
		else if (result == BUS_RESULT_EVENT) {
			bus_endpt_recv_evt(endpt, &epid, &type, &pkt);
			if (endpt->callback.on_evt)
				endpt->callback.on_evt(endpt, epid, type, &pkt, endpt->callback.user_data);
			if (pkt)
				iobuffer_dec_ref(pkt);
		}
		else if (result == BUS_RESULT_SYSTEM) {
			bus_endpt_recv_sys(endpt, &epid, &state);
			if (endpt->callback.on_sys)
				endpt->callback.on_sys(endpt, epid, state, endpt->callback.user_data);
		}
		else if (result == BUS_RESULT_MSG) {
			msg_t* msg = NULL;
			bus_endpt_recv_msg(endpt, &msg);
			if (endpt->callback.on_msg) {
				endpt->callback.on_msg(endpt, 
					msg->type,
					msg->nparam, 
					msg->params, 
					msg->evt ? &msg->evt_result : NULL,
					endpt->callback.user_data);
				if (msg->evt) {
					WLog_DBG(TAG, "after recv msg, send finished evt.");
					SetEvent(msg->evt);
				}
				else {
					WLog_DBG(TAG, "free msg");
					free_msg(msg);
				}
			}
			else {
				if (msg->evt) {
					msg->evt_result = -1;
					WLog_DBG(TAG, "after on msg failed, send finished evt.");
					SetEvent(msg->evt);
				}
				else {
					WLog_DBG(TAG, "free msg");
					free_msg(msg);
				}
			}
		}
		else {
			assert(0);
			rc = -1;
		}
	}

	return rc;
}

TOOLKIT_API int bus_endpt_set_quit_flag(bus_endpt_t* endpt)
{
	endpt->quit_flag = 1;
	return 0;
}

TOOLKIT_API int bus_endpt_get_quit_flag(bus_endpt_t* endpt)
{
	return endpt->quit_flag;
}