+ /* TODO: set non-blocking */
+ return (psmb_result_t){PSMB_OK};
+}
+
+static struct in6_addr multiaddr(struct in6_addr prefix,
+ unsigned char prefixlen, uint64_t suffix)
+{
+ struct in6_addr result = prefix;
+ unsigned char len = prefixlen > 64 ? prefixlen : 64;
+ uint64_t mask = len == 64 ? ~(uint64_t)0 : ((uint64_t)1 << len) - 1;
+
+ *(uint64_t *)(&result.__in6_u.__u6_addr32[2]) &= ~mask;
+ *(uint64_t *)(&result.__in6_u.__u6_addr32[2]) |= (suffix & mask);
+ return result;
+}
+
+static psmb_result_t psmb_sub_unsub(psmb_ctx_t *ctx, char *channel, int option)
+{
+ struct ipv6_mreq mreq = { 0 };
+ char mgrp_str[INET6_ADDRSTRLEN+1];
+
+ if (ctx->fd == -1) {
+ LOG(ctx, LOG_ERR, "subscribe: psmb is not open");
+ errno = EINVAL;
+ return (psmb_result_t){PSMB_ERROR};
+ }
+ mreq.ipv6mr_multiaddr = multiaddr(ctx->prefix, ctx->prefixlen,
+ hash64(channel, strlen(channel)));
+ (void)inet_ntop(AF_INET6, &mreq.ipv6mr_multiaddr,
+ mgrp_str, sizeof(mgrp_str));
+ LOG(ctx, LOG_DEBUG, "using multiaddr %s for channel \"%s\"",
+ mgrp_str, channel);
+ mreq.ipv6mr_interface = 0; /* how to use this??? */
+ if (setsockopt(ctx->fd, IPPROTO_IPV6, option,
+ (void *)&mreq, sizeof(mreq)) == -1) {
+ int sverr = errno;
+ LOG(ctx, LOG_ERR, "add_membership(): %m");
+ errno = sverr;
+ return (psmb_result_t){PSMB_ERROR};
+ }
+ return (psmb_result_t){PSMB_OK};
+}
+
+psmb_result_t psmb_subscribe(psmb_ctx_t *ctx, char *channel)
+{
+ return psmb_sub_unsub(ctx, channel, IPV6_ADD_MEMBERSHIP);
+}
+
+psmb_result_t psmb_unsubscribe(psmb_ctx_t *ctx, char *channel)
+{
+ return psmb_sub_unsub(ctx, channel, IPV6_DROP_MEMBERSHIP);
+}
+
+psmb_result_t psmb_ev_rd(psmb_ctx_t *ctx)
+{
+ char buf[MAXBUFLEN];
+ char cmsgbuf[MAXBUFLEN];
+ struct iovec iov[1];
+ iov[0].iov_base=buf;
+ iov[0].iov_len=sizeof(buf);
+ struct cmsghdr *cmsg;
+ struct msghdr message;
+ message.msg_name=&their_addr;
+message.msg_namelen=sizeof(their_addr);
+message.msg_iov=iov;
+message.msg_iovlen=1;
+message.msg_control=cmsgbuf;
+message.msg_controllen=MAXBUFLEN;
+
+ if ((numbytes = recvmsg(sockfd, &message, 0)) == -1) {
+ /* error */ ;
+ }
+ for (cmsg = CMSG_FIRSTHDR(&message); cmsg != NULL; cmsg = CMSG_NXTHDR(&message, cmsg)) {
+ if (cmsg->cmsg_level != IPPROTO_IP || cmsg->cmsg_type != IP_PKTINFO)
+ continue;
+ struct in_pktinfo *pi = CMSG_DATA(cmsg);
+ addr = pi->ipi_spec_dst.s_addr;
+ }
+
+
+ return (psmb_result_t){PSMB_OK};
+}
+
+psmb_result_t psmb_ev_wr(psmb_ctx_t *ctx)
+{
+ sock_opt_addr.s_addr = addr;
+ setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_IF, &sock_opt_addr, sizeof(sock_opt_addr));
+ sendto(sockfd, buffer, len, 0, (struct sockaddr *)&destination, sizeof destination);
+