+
+/*
+ * Return user specified netmask, modified by any mask we might determine
+ * for address `addr' (in network byte order).
+ * Here we scan through the system's list of interfaces, looking for
+ * any non-point-to-point interfaces which might appear to be on the same
+ * network as `addr'. If we find any, we OR in their netmask to the
+ * user-specified netmask.
+ */
+#define MAX_IFS 32
+
+u_int32_t
+GetMask(addr)
+ u_int32_t addr;
+{
+ u_int32_t mask, nmask, ina;
+ struct ifreq *ifr, *ifend, ifreq;
+ struct ifconf ifc;
+ struct ifreq ifs[MAX_IFS];
+
+ addr = ntohl(addr);
+ if (IN_CLASSA(addr)) /* determine network mask for address class */
+ nmask = IN_CLASSA_NET;
+ else if (IN_CLASSB(addr))
+ nmask = IN_CLASSB_NET;
+ else
+ nmask = IN_CLASSC_NET;
+ /* class D nets are disallowed by bad_ip_adrs */
+ mask = netmask | htonl(nmask);
+
+ /*
+ * Scan through the system's network interfaces.
+ */
+ ifc.ifc_len = sizeof(ifs);
+ ifc.ifc_req = ifs;
+ if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0) {
+ syslog(LOG_WARNING, "ioctl(SIOCGIFCONF): %m");
+ return mask;
+ }
+ ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
+ for (ifr = ifc.ifc_req; ifr < ifend; ++ifr) {
+ /*
+ * Check the interface's internet address.
+ */
+ if (ifr->ifr_addr.sa_family != AF_INET)
+ continue;
+ ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
+ if ((ntohl(ina) & nmask) != (addr & nmask))
+ continue;
+ /*
+ * Check that the interface is up, and not point-to-point or loopback.
+ */
+ strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
+ if (ioctl(sockfd, SIOCGIFFLAGS, &ifreq) < 0)
+ continue;
+ if ((ifreq.ifr_flags & (IFF_UP|IFF_POINTOPOINT|IFF_LOOPBACK))
+ != IFF_UP)
+ continue;
+ /*
+ * Get its netmask and OR it into our mask.
+ */
+ if (ioctl(sockfd, SIOCGIFNETMASK, &ifreq) < 0)
+ continue;
+ mask |= ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr.s_addr;
+ }
+
+ return mask;
+}
+
+/*
+ * Code for locking/unlocking the serial device.
+ * This code is derived from chat.c.
+ */
+
+#if defined(SUNOS) && SUNOS >= 41 && !defined(HDB)
+#define HDB 1
+#endif
+
+#ifndef LOCK_DIR
+# ifdef HDB
+# define PIDSTRING
+# define LOCK_PREFIX "/usr/spool/locks/LCK.."
+# else /* HDB */
+# define LOCK_PREFIX "/usr/spool/uucp/LCK.."
+# endif /* HDB */
+#endif /* LOCK_DIR */
+
+/*
+ * lock - create a lock file for the named device.
+ */
+int
+lock(dev)
+ char *dev;
+{
+ char hdb_lock_buffer[12];
+ int fd, pid, n;
+ char *p;
+
+ if ((p = strrchr(dev, '/')) != NULL)
+ dev = p + 1;
+ lock_file = malloc(strlen(LOCK_PREFIX) + strlen(dev) + 1);
+ if (lock_file == NULL)
+ novm("lock file name");
+ strcat(strcpy(lock_file, LOCK_PREFIX), dev);
+
+ while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
+ if (errno == EEXIST
+ && (fd = open(lock_file, O_RDONLY, 0)) >= 0) {
+ /* Read the lock file to find out who has the device locked */
+#ifdef PIDSTRING
+ n = read(fd, hdb_lock_buffer, 11);
+ if (n > 0) {
+ hdb_lock_buffer[n] = 0;
+ pid = atoi(hdb_lock_buffer);
+ }
+#else
+ n = read(fd, &pid, sizeof(pid));
+#endif
+ if (n <= 0) {
+ syslog(LOG_ERR, "Can't read pid from lock file %s", lock_file);
+ close(fd);
+ } else {
+ if (kill(pid, 0) == -1 && errno == ESRCH) {
+ /* pid no longer exists - remove the lock file */
+ if (unlink(lock_file) == 0) {
+ close(fd);
+ syslog(LOG_NOTICE, "Removed stale lock on %s (pid %d)",
+ dev, pid);
+ continue;
+ } else
+ syslog(LOG_WARNING, "Couldn't remove stale lock on %s",
+ dev);
+ } else
+ syslog(LOG_NOTICE, "Device %s is locked by pid %d",
+ dev, pid);
+ }
+ close(fd);
+ } else
+ syslog(LOG_ERR, "Can't create lock file %s: %m", lock_file);
+ free(lock_file);
+ lock_file = NULL;
+ return -1;
+ }
+
+#ifdef PIDSTRING
+ sprintf(hdb_lock_buffer, "%10d\n", getpid());
+ write(fd, hdb_lock_buffer, 11);
+#else
+ pid = getpid();
+ write(fd, &pid, sizeof pid);
+#endif
+
+ close(fd);
+ return 0;
+}
+
+/*
+ * unlock - remove our lockfile
+ */
+void
+unlock()
+{
+ if (lock_file) {
+ unlink(lock_file);
+ free(lock_file);
+ lock_file = NULL;
+ }
+}