/* * Event notification code. * (C) 2005 FUJITA Tomonori <tomof@acm.org> * This code is licenced under the GPL. * * Some functions are based on open-iscsi code * written by Dmitry Yusupov, Alex Aizman. */#include <errno.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <unistd.h>#include <asm/types.h>#include <sys/socket.h>#include <linux/netlink.h>#include "iscsid.h"static struct sockaddr_nl src_addr, dest_addr;static int nl_write(int fd, void *data, int len){	struct iovec iov[2];	struct msghdr msg;	struct nlmsghdr nlh;	iov[0].iov_base = &nlh;	iov[0].iov_len = sizeof(nlh);	iov[1].iov_base = data;	iov[1].iov_len = NLMSG_SPACE(len) - sizeof(nlh);	nlh.nlmsg_len = NLMSG_SPACE(len);	nlh.nlmsg_pid = getpid();	nlh.nlmsg_flags = 0;	nlh.nlmsg_type = 0;	memset(&msg, 0, sizeof(msg));	msg.msg_name= (void*)&dest_addr;	msg.msg_namelen = sizeof(dest_addr);	msg.msg_iov = iov;	msg.msg_iovlen = 2;	return sendmsg(fd, &msg, 0);}static int nl_read(int fd, void *data, int len){	struct iovec iov[2];	struct msghdr msg;	struct nlmsghdr nlh;	iov[0].iov_base = &nlh;	iov[0].iov_len = sizeof(nlh);	iov[1].iov_base = data;	iov[1].iov_len = len;	memset(&msg, 0, sizeof(msg));	msg.msg_name= (void*)&src_addr;	msg.msg_namelen = sizeof(src_addr);	msg.msg_iov = iov;	msg.msg_iovlen = 2;	return recvmsg(fd, &msg, MSG_DONTWAIT);}void handle_iscsi_events(int fd){	struct session *session;	struct iet_event event;	int res;retry:	if ((res = nl_read(fd, &event, sizeof(event))) < 0) {		if (errno == EAGAIN)			return;		if (errno == EINTR)			goto retry;		log_error("read netlink fd (%d)", errno);		exit(1);	}	log_debug(1, "conn %u session %#" PRIx64 " target %u, state %u",		  event.cid, event.sid, event.tid, event.state);	switch (event.state) {	case E_CONN_CLOSE:		if (!(session = session_find_id(event.tid, event.sid))) {			log_warning("session %#" PRIx64 " not found?", event.sid);			goto retry;		}		if (!--session->conn_cnt)			session_remove(session);		break;	default:		log_warning("%s(%d) %u\n", __FUNCTION__, __LINE__, event.state);		exit(-1);		break;	}}int nl_open(void){	int nl_fd, res;	nl_fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_IET);	if (nl_fd == -1) {		log_error("%s %d\n", __FUNCTION__, errno);		return -1;	}	memset(&src_addr, 0, sizeof(src_addr));	src_addr.nl_family = AF_NETLINK;	src_addr.nl_pid = getpid();	src_addr.nl_groups = 0; /* not in mcast groups */	memset(&dest_addr, 0, sizeof(dest_addr));	dest_addr.nl_family = AF_NETLINK;	dest_addr.nl_pid = 0; /* kernel */	dest_addr.nl_groups = 0; /* unicast */	res = nl_write(nl_fd, NULL, 0);	if (res < 0) {		log_error("%s %d\n", __FUNCTION__, res);		return res;	}	return nl_fd;}