3038a8aa612dc62c7eb21a587d59c2061145c3ef
[dragonfly.git] / usr.bin / netstat / if.c
1 /*
2  * Copyright (c) 1983, 1988, 1993
3  *      The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *      This product includes software developed by the University of
16  *      California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#)if.c     8.3 (Berkeley) 4/28/95
34  * $FreeBSD: src/usr.bin/netstat/if.c,v 1.32.2.9 2001/09/17 14:35:46 ru Exp $
35  * $DragonFly: src/usr.bin/netstat/if.c,v 1.2 2003/06/17 04:29:30 dillon Exp $
36  */
37
38 #include <sys/types.h>
39 #include <sys/protosw.h>
40 #include <sys/socket.h>
41 #include <sys/sysctl.h>
42 #include <sys/time.h>
43
44 #include <net/if.h>
45 #include <net/if_var.h>
46 #include <net/if_dl.h>
47 #include <net/if_types.h>
48 #include <net/bridge.h>
49 #include <net/ethernet.h>
50 #include <netinet/in.h>
51 #include <netinet/in_var.h>
52 #include <netipx/ipx.h>
53 #include <netipx/ipx_if.h>
54 #ifdef NS
55 #include <netns/ns.h>
56 #include <netns/ns_if.h>
57 #endif
58 #ifdef ISO
59 #include <netiso/iso.h>
60 #include <netiso/iso_var.h>
61 #endif
62 #include <arpa/inet.h>
63
64 #include <signal.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <unistd.h>
69
70 #include "netstat.h"
71
72 #define YES     1
73 #define NO      0
74
75 static void sidewaysintpr (u_int, u_long);
76 static void catchalarm (int);
77
78 #ifdef INET6
79 char *netname6 (struct sockaddr_in6 *, struct in6_addr *);
80 static char ntop_buf[INET6_ADDRSTRLEN];         /* for inet_ntop() */
81 static int bdg_done;
82 #endif
83
84 /* print bridge statistics */
85 void
86 bdg_stats(u_long dummy __unused, char *name, int af __unused)
87 {
88     int i;
89     size_t slen ;
90     struct bdg_stats s ;
91     int mib[4] ;
92
93     slen = sizeof(s);
94
95     mib[0] = CTL_NET ;
96     mib[1] = PF_LINK ;
97     mib[2] = IFT_ETHER ;
98     mib[3] = PF_BDG ;
99     if (sysctl(mib,4, &s,&slen,NULL,0)==-1)
100         return ; /* no bridging */
101 #ifdef INET6
102     if (bdg_done != 0)
103         return;
104     else
105         bdg_done = 1;
106 #endif
107     printf("-- Bridging statistics (%s) --\n", name) ;
108     printf(
109 "Name          In      Out  Forward     Drop    Bcast    Mcast    Local  Unknown\n");
110     for (i = 0 ; i < 16 ; i++) {
111         if (s.s[i].name[0])
112         printf("%-6s %9ld%9ld%9ld%9ld%9ld%9ld%9ld%9ld\n",
113           s.s[i].name,
114           s.s[i].p_in[(int)BDG_IN],
115           s.s[i].p_in[(int)BDG_OUT],
116           s.s[i].p_in[(int)BDG_FORWARD],
117           s.s[i].p_in[(int)BDG_DROP],
118           s.s[i].p_in[(int)BDG_BCAST],
119           s.s[i].p_in[(int)BDG_MCAST],
120           s.s[i].p_in[(int)BDG_LOCAL],
121           s.s[i].p_in[(int)BDG_UNKNOWN] );
122     }
123 }
124
125
126
127
128 /*
129  * Display a formatted value, or a '-' in the same space.
130  */
131 static void
132 show_stat(const char *fmt, int width, u_long value, short showvalue)
133 {
134         char newfmt[32];
135
136         /* Construct the format string */
137         if (showvalue) {
138                 sprintf(newfmt, "%%%d%s", width, fmt);
139                 printf(newfmt, value);
140         } else {
141                 sprintf(newfmt, "%%%ds", width);
142                 printf(newfmt, "-");
143         }
144 }
145
146
147
148 /*
149  * Print a description of the network interfaces.
150  */
151 void
152 intpr(int interval, u_long ifnetaddr, void (*pfunc)(char *))
153 {
154         struct ifnet ifnet;
155         struct ifnethead ifnethead;
156         union {
157                 struct ifaddr ifa;
158                 struct in_ifaddr in;
159 #ifdef INET6
160                 struct in6_ifaddr in6;
161 #endif
162                 struct ipx_ifaddr ipx;
163 #ifdef NS
164                 struct ns_ifaddr ns;
165 #endif
166 #ifdef ISO
167                 struct iso_ifaddr iso;
168 #endif
169         } ifaddr;
170         u_long ifaddraddr;
171         u_long ifaddrfound;
172         u_long ifnetfound;
173         u_long opackets;
174         u_long ipackets;
175         u_long obytes;
176         u_long ibytes;
177         u_long oerrors;
178         u_long ierrors;
179         u_long collisions;
180         short timer;
181         int drops;
182         struct sockaddr *sa = NULL;
183         char name[32], tname[16];
184         short network_layer;
185         short link_layer;
186
187         if (ifnetaddr == 0) {
188                 printf("ifnet: symbol not defined\n");
189                 return;
190         }
191         if (interval) {
192                 sidewaysintpr((unsigned)interval, ifnetaddr);
193                 return;
194         }
195         if (kread(ifnetaddr, (char *)&ifnethead, sizeof ifnethead))
196                 return;
197         ifnetaddr = (u_long)TAILQ_FIRST(&ifnethead);
198         if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet))
199                 return;
200
201         if (!pfunc) {
202                 printf("%-5.5s %-5.5s %-13.13s %-15.15s %8.8s %5.5s",
203                        "Name", "Mtu", "Network", "Address", "Ipkts", "Ierrs");
204                 if (bflag)
205                         printf(" %10.10s","Ibytes");
206                 printf(" %8.8s %5.5s", "Opkts", "Oerrs");
207                 if (bflag)
208                         printf(" %10.10s","Obytes");
209                 printf(" %5s", "Coll");
210                 if (tflag)
211                         printf(" %s", "Time");
212                 if (dflag)
213                         printf(" %s", "Drop");
214                 putchar('\n');
215         }
216         ifaddraddr = 0;
217         while (ifnetaddr || ifaddraddr) {
218                 struct sockaddr_in *sin;
219 #ifdef INET6
220                 struct sockaddr_in6 *sin6;
221 #endif
222                 register char *cp;
223                 int n, m;
224
225                 network_layer = 0;
226                 link_layer = 0;
227
228                 if (ifaddraddr == 0) {
229                         ifnetfound = ifnetaddr;
230                         if (kread(ifnetaddr, (char *)&ifnet, sizeof ifnet) ||
231                             kread((u_long)ifnet.if_name, tname, 16))
232                                 return;
233                         tname[15] = '\0';
234                         ifnetaddr = (u_long)TAILQ_NEXT(&ifnet, if_link);
235                         snprintf(name, 32, "%s%d", tname, ifnet.if_unit);
236                         if (interface != 0 && (strcmp(name, interface) != 0))
237                                 continue;
238                         cp = index(name, '\0');
239
240                         if (pfunc) {
241                                 (*pfunc)(name);
242                                 continue;
243                         }
244
245                         if ((ifnet.if_flags&IFF_UP) == 0)
246                                 *cp++ = '*';
247                         *cp = '\0';
248                         ifaddraddr = (u_long)TAILQ_FIRST(&ifnet.if_addrhead);
249                 }
250                 ifaddrfound = ifaddraddr;
251
252                 /*
253                  * Get the interface stats.  These may get
254                  * overriden below on a per-interface basis.
255                  */
256                 opackets = ifnet.if_opackets;
257                 ipackets = ifnet.if_ipackets;
258                 obytes = ifnet.if_obytes;
259                 ibytes = ifnet.if_ibytes;
260                 oerrors = ifnet.if_oerrors;
261                 ierrors = ifnet.if_ierrors;
262                 collisions = ifnet.if_collisions;
263                 timer = ifnet.if_timer;
264                 drops = ifnet.if_snd.ifq_drops;
265
266                 if (ifaddraddr == 0) {
267                         printf("%-5.5s %-5lu ", name, ifnet.if_mtu);
268                         printf("%-13.13s ", "none");
269                         printf("%-15.15s ", "none");
270                 } else {
271                         if (kread(ifaddraddr, (char *)&ifaddr, sizeof ifaddr)) {
272                                 ifaddraddr = 0;
273                                 continue;
274                         }
275 #define CP(x) ((char *)(x))
276                         cp = (CP(ifaddr.ifa.ifa_addr) - CP(ifaddraddr)) +
277                                 CP(&ifaddr);
278                         sa = (struct sockaddr *)cp;
279                         if (af != AF_UNSPEC && sa->sa_family != af) {
280                                 ifaddraddr =
281                                     (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
282                                 continue;
283                         }
284                         printf("%-5.5s %-5lu ", name, ifnet.if_mtu);
285                         switch (sa->sa_family) {
286                         case AF_UNSPEC:
287                                 printf("%-13.13s ", "none");
288                                 printf("%-15.15s ", "none");
289                                 break;
290                         case AF_INET:
291                                 sin = (struct sockaddr_in *)sa;
292 #ifdef notdef
293                                 /* can't use inet_makeaddr because kernel
294                                  * keeps nets unshifted.
295                                  */
296                                 in = inet_makeaddr(ifaddr.in.ia_subnet,
297                                         INADDR_ANY);
298                                 printf("%-13.13s ", netname(in.s_addr,
299                                     ifaddr.in.ia_subnetmask));
300 #else
301                                 printf("%-13.13s ",
302                                     netname(htonl(ifaddr.in.ia_subnet),
303                                     ifaddr.in.ia_subnetmask));
304 #endif
305                                 printf("%-15.15s ",
306                                     routename(sin->sin_addr.s_addr));
307
308                                 network_layer = 1;
309                                 break;
310 #ifdef INET6
311                         case AF_INET6:
312                                 sin6 = (struct sockaddr_in6 *)sa;
313                                 printf("%-11.11s ",
314                                        netname6(&ifaddr.in6.ia_addr,
315                                                 &ifaddr.in6.ia_prefixmask.sin6_addr));
316                                 printf("%-17.17s ",
317                                     (char *)inet_ntop(AF_INET6,
318                                         &sin6->sin6_addr,
319                                         ntop_buf, sizeof(ntop_buf)));
320
321                                 network_layer = 1;
322                                 break;
323 #endif /*INET6*/
324                         case AF_IPX:
325                                 {
326                                 struct sockaddr_ipx *sipx =
327                                         (struct sockaddr_ipx *)sa;
328                                 u_long net;
329                                 char netnum[10];
330
331                                 *(union ipx_net *) &net = sipx->sipx_addr.x_net;
332                                 sprintf(netnum, "%lx", (u_long)ntohl(net));
333                                 printf("ipx:%-8s  ", netnum);
334 /*                              printf("ipx:%-8s ", netname(net, 0L)); */
335                                 printf("%-15s ",
336                                     ipx_phost((struct sockaddr *)sipx));
337                                 }
338                                 break;
339
340                         case AF_APPLETALK:
341                                 printf("atalk:%-12.12s ",atalk_print(sa,0x10) );
342                                 printf("%-9.9s  ",atalk_print(sa,0x0b) );
343                                 break;
344 #ifdef NS
345                         case AF_NS:
346                                 {
347                                 struct sockaddr_ns *sns =
348                                         (struct sockaddr_ns *)sa;
349                                 u_long net;
350                                 char netnum[10];
351
352                                 *(union ns_net *) &net = sns->sns_addr.x_net;
353                                 sprintf(netnum, "%lxH", ntohl(net));
354                                 upHex(netnum);
355                                 printf("ns:%-8s ", netnum);
356                                 printf("%-15s ",
357                                     ns_phost((struct sockaddr *)sns));
358                                 }
359                                 break;
360 #endif
361                         case AF_LINK:
362                                 {
363                                 struct sockaddr_dl *sdl =
364                                         (struct sockaddr_dl *)sa;
365                                 char linknum[10];
366                                 cp = (char *)LLADDR(sdl);
367                                 n = sdl->sdl_alen;
368                                 sprintf(linknum, "<Link#%d>", sdl->sdl_index);
369                                 m = printf("%-11.11s ", linknum);
370                                 }
371                                 goto hexprint;
372                         default:
373                                 m = printf("(%d)", sa->sa_family);
374                                 for (cp = sa->sa_len + (char *)sa;
375                                         --cp > sa->sa_data && (*cp == 0);) {}
376                                 n = cp - sa->sa_data + 1;
377                                 cp = sa->sa_data;
378                         hexprint:
379                                 while (--n >= 0)
380                                         m += printf("%02x%c", *cp++ & 0xff,
381                                                     n > 0 ? ':' : ' ');
382                                 m = 30 - m;
383                                 while (m-- > 0)
384                                         putchar(' ');
385
386                                 link_layer = 1;
387                                 break;
388                         }
389
390                         /*
391                          * Fixup the statistics for interfaces that
392                          * update stats for their network addresses
393                          */
394                         if (network_layer) {
395                                 opackets = ifaddr.in.ia_ifa.if_opackets;
396                                 ipackets = ifaddr.in.ia_ifa.if_ipackets;
397                                 obytes = ifaddr.in.ia_ifa.if_obytes;
398                                 ibytes = ifaddr.in.ia_ifa.if_ibytes;
399                         }
400
401                         ifaddraddr = (u_long)TAILQ_NEXT(&ifaddr.ifa, ifa_link);
402                 }
403
404                 show_stat("lu", 8, ipackets, link_layer|network_layer);
405                 printf(" ");
406                 show_stat("lu", 5, ierrors, link_layer);
407                 printf(" ");
408                 if (bflag) {
409                         show_stat("lu", 10, ibytes, link_layer|network_layer);
410                         printf(" ");
411                 }
412                 show_stat("lu", 8, opackets, link_layer|network_layer);
413                 printf(" ");
414                 show_stat("lu", 5, oerrors, link_layer);
415                 printf(" ");
416                 if (bflag) {
417                         show_stat("lu", 10, obytes, link_layer|network_layer);
418                         printf(" ");
419                 }
420                 show_stat("lu", 5, collisions, link_layer);
421                 if (tflag) {
422                         printf(" ");
423                         show_stat("d", 3, timer, link_layer);
424                 }
425                 if (dflag) {
426                         printf(" ");
427                         show_stat("d", 3, drops, link_layer);
428                 }
429                 putchar('\n');
430                 if (aflag && ifaddrfound) {
431                         /*
432                          * Print family's multicast addresses
433                          */
434                         u_long multiaddr;
435                         struct ifmultiaddr ifma;
436                         union {
437                                 struct sockaddr sa;
438                                 struct sockaddr_in in;
439 #ifdef INET6
440                                 struct sockaddr_in6 in6;
441 #endif /* INET6 */
442                                 struct sockaddr_dl dl;
443                         } msa;
444                         const char *fmt;
445
446                         for(multiaddr = (u_long)ifnet.if_multiaddrs.lh_first;
447                             multiaddr;
448                             multiaddr = (u_long)ifma.ifma_link.le_next) {
449                                 if (kread(multiaddr, (char *)&ifma,
450                                           sizeof ifma))
451                                         break;
452                                 if (kread((u_long)ifma.ifma_addr, (char *)&msa,
453                                           sizeof msa))
454                                         break;
455                                 if (msa.sa.sa_family != sa->sa_family)
456                                         continue;
457                                 
458                                 fmt = 0;
459                                 switch (msa.sa.sa_family) {
460                                 case AF_INET:
461                                         fmt = routename(msa.in.sin_addr.s_addr);
462                                         break;
463 #ifdef INET6
464                                 case AF_INET6:
465                                         printf("%23s %-19.19s(refs: %d)\n", "",
466                                                inet_ntop(AF_INET6,
467                                                          &msa.in6.sin6_addr,
468                                                          ntop_buf,
469                                                          sizeof(ntop_buf)),
470                                                ifma.ifma_refcount);
471                                         break;
472 #endif /* INET6 */
473                                 case AF_LINK:
474                                         switch (msa.dl.sdl_type) {
475                                         case IFT_ETHER:
476                                         case IFT_FDDI:
477                                                 fmt = ether_ntoa(
478                                                         (struct ether_addr *)
479                                                         LLADDR(&msa.dl));
480                                                 break;
481                                         }
482                                         break;
483                                 }
484                                 if (fmt)
485                                         printf("%23s %s\n", "", fmt);
486                         }
487                 }
488         }
489 }
490
491 struct  iftot {
492         SLIST_ENTRY(iftot) chain;
493         char    ift_name[16];           /* interface name */
494         u_long  ift_ip;                 /* input packets */
495         u_long  ift_ie;                 /* input errors */
496         u_long  ift_op;                 /* output packets */
497         u_long  ift_oe;                 /* output errors */
498         u_long  ift_co;                 /* collisions */
499         u_int   ift_dr;                 /* drops */
500         u_long  ift_ib;                 /* input bytes */
501         u_long  ift_ob;                 /* output bytes */
502 };
503
504 u_char  signalled;                      /* set if alarm goes off "early" */
505
506 /*
507  * Print a running summary of interface statistics.
508  * Repeat display every interval seconds, showing statistics
509  * collected over that interval.  Assumes that interval is non-zero.
510  * First line printed at top of screen is always cumulative.
511  * XXX - should be rewritten to use ifmib(4).
512  */
513 static void
514 sidewaysintpr(unsigned interval, u_long off)
515 {
516         struct ifnet ifnet;
517         u_long firstifnet;
518         struct ifnethead ifnethead;
519         struct iftot *iftot, *ip, *ipn, *total, *sum, *interesting;
520         register int line;
521         int oldmask, first;
522         u_long interesting_off;
523
524         if (kread(off, (char *)&ifnethead, sizeof ifnethead))
525                 return;
526         firstifnet = (u_long)TAILQ_FIRST(&ifnethead);
527
528         if ((iftot = malloc(sizeof(struct iftot))) == NULL) {
529                 printf("malloc failed\n");
530                 exit(1);
531         }
532         memset(iftot, 0, sizeof(struct iftot));
533
534         interesting = NULL;
535         interesting_off = 0;
536         for (off = firstifnet, ip = iftot; off;) {
537                 char name[16], tname[16];
538
539                 if (kread(off, (char *)&ifnet, sizeof ifnet))
540                         break;
541                 if (kread((u_long)ifnet.if_name, tname, 16))
542                         break;
543                 tname[15] = '\0';
544                 snprintf(name, 16, "%s%d", tname, ifnet.if_unit);
545                 if (interface && strcmp(name, interface) == 0) {
546                         interesting = ip;
547                         interesting_off = off;
548                 }
549                 snprintf(ip->ift_name, 16, "(%s)", name);;
550                 if ((ipn = malloc(sizeof(struct iftot))) == NULL) {
551                         printf("malloc failed\n");
552                         exit(1);
553                 }
554                 memset(ipn, 0, sizeof(struct iftot));
555                 SLIST_NEXT(ip, chain) = ipn;
556                 ip = ipn;
557                 off = (u_long)TAILQ_NEXT(&ifnet, if_link);
558         }
559         if ((total = malloc(sizeof(struct iftot))) == NULL) {
560                 printf("malloc failed\n");
561                 exit(1);
562         }
563         memset(total, 0, sizeof(struct iftot));
564         if ((sum = malloc(sizeof(struct iftot))) == NULL) {
565                 printf("malloc failed\n");
566                 exit(1);
567         }
568         memset(sum, 0, sizeof(struct iftot));
569
570
571         (void)signal(SIGALRM, catchalarm);
572         signalled = NO;
573         (void)alarm(interval);
574         first = 1;
575 banner:
576         printf("%17s %14s %16s", "input",
577             interesting ? interesting->ift_name : "(Total)", "output");
578         putchar('\n');
579         printf("%10s %5s %10s %10s %5s %10s %5s",
580             "packets", "errs", "bytes", "packets", "errs", "bytes", "colls");
581         if (dflag)
582                 printf(" %5.5s", "drops");
583         putchar('\n');
584         fflush(stdout);
585         line = 0;
586 loop:
587         if (interesting != NULL) {
588                 ip = interesting;
589                 if (kread(interesting_off, (char *)&ifnet, sizeof ifnet)) {
590                         printf("???\n");
591                         exit(1);
592                 };
593                 if (!first) {
594                         printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
595                                 ifnet.if_ipackets - ip->ift_ip,
596                                 ifnet.if_ierrors - ip->ift_ie,
597                                 ifnet.if_ibytes - ip->ift_ib,
598                                 ifnet.if_opackets - ip->ift_op,
599                                 ifnet.if_oerrors - ip->ift_oe,
600                                 ifnet.if_obytes - ip->ift_ob,
601                                 ifnet.if_collisions - ip->ift_co);
602                         if (dflag)
603                                 printf(" %5u", ifnet.if_snd.ifq_drops - ip->ift_dr);
604                 }
605                 ip->ift_ip = ifnet.if_ipackets;
606                 ip->ift_ie = ifnet.if_ierrors;
607                 ip->ift_ib = ifnet.if_ibytes;
608                 ip->ift_op = ifnet.if_opackets;
609                 ip->ift_oe = ifnet.if_oerrors;
610                 ip->ift_ob = ifnet.if_obytes;
611                 ip->ift_co = ifnet.if_collisions;
612                 ip->ift_dr = ifnet.if_snd.ifq_drops;
613         } else {
614                 sum->ift_ip = 0;
615                 sum->ift_ie = 0;
616                 sum->ift_ib = 0;
617                 sum->ift_op = 0;
618                 sum->ift_oe = 0;
619                 sum->ift_ob = 0;
620                 sum->ift_co = 0;
621                 sum->ift_dr = 0;
622                 for (off = firstifnet, ip = iftot;
623                      off && SLIST_NEXT(ip, chain) != NULL;
624                      ip = SLIST_NEXT(ip, chain)) {
625                         if (kread(off, (char *)&ifnet, sizeof ifnet)) {
626                                 off = 0;
627                                 continue;
628                         }
629                         sum->ift_ip += ifnet.if_ipackets;
630                         sum->ift_ie += ifnet.if_ierrors;
631                         sum->ift_ib += ifnet.if_ibytes;
632                         sum->ift_op += ifnet.if_opackets;
633                         sum->ift_oe += ifnet.if_oerrors;
634                         sum->ift_ob += ifnet.if_obytes;
635                         sum->ift_co += ifnet.if_collisions;
636                         sum->ift_dr += ifnet.if_snd.ifq_drops;
637                         off = (u_long)TAILQ_NEXT(&ifnet, if_link);
638                 }
639                 if (!first) {
640                         printf("%10lu %5lu %10lu %10lu %5lu %10lu %5lu",
641                                 sum->ift_ip - total->ift_ip,
642                                 sum->ift_ie - total->ift_ie,
643                                 sum->ift_ib - total->ift_ib,
644                                 sum->ift_op - total->ift_op,
645                                 sum->ift_oe - total->ift_oe,
646                                 sum->ift_ob - total->ift_ob,
647                                 sum->ift_co - total->ift_co);
648                         if (dflag)
649                                 printf(" %5u", sum->ift_dr - total->ift_dr);
650                 }
651                 *total = *sum;
652         }
653         if (!first)
654                 putchar('\n');
655         fflush(stdout);
656         oldmask = sigblock(sigmask(SIGALRM));
657         if (! signalled) {
658                 sigpause(0);
659         }
660         sigsetmask(oldmask);
661         signalled = NO;
662         (void)alarm(interval);
663         line++;
664         first = 0;
665         if (line == 21)
666                 goto banner;
667         else
668                 goto loop;
669         /*NOTREACHED*/
670 }
671
672 /*
673  * Called if an interval expires before sidewaysintpr has completed a loop.
674  * Sets a flag to not wait for the alarm.
675  */
676 static void
677 catchalarm(int signo __unused)
678 {
679         signalled = YES;
680 }