The Tcpdump Group git mirrors - libpcap/blob - tests/nonblocktest.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
   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: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #ifndef lint
  23 static const char copyright[] =
  24     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
  25 The Regents of the University of California.  All rights reserved.\n";
  26 #endif
  27
  28 #include <pcap.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <stdarg.h>
  33 #include <unistd.h>
  34 #include <errno.h>
  35 #include <sys/types.h>
  36 #include <sys/select.h>
  37 #include <poll.h>
  38
  39 char *program_name;
  40
  41 /* Forwards */
  42 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  43 static void usage(void) __attribute__((noreturn));
  44 static void error(const char *, ...);
  45 static void warning(const char *, ...);
  46 static char *copy_argv(char **);
  47
  48 static pcap_t *pd;
  49
  50 extern int optind;
  51 extern int opterr;
  52 extern char *optarg;
  53
  54 int
  55 main(int argc, char **argv)
  56 {
  57         register int op;
  58         bpf_u_int32 localnet, netmask;
  59         register char *cp, *cmdbuf, *device;
  60         struct bpf_program fcode;
  61         char ebuf[PCAP_ERRBUF_SIZE];
  62         int status;
  63         int packet_count;
  64
  65         device = NULL;
  66         if ((cp = strrchr(argv[0], '/')) != NULL)
  67                 program_name = cp + 1;
  68         else
  69                 program_name = argv[0];
  70
  71         opterr = 0;
  72         while ((op = getopt(argc, argv, "i:")) != -1) {
  73                 switch (op) {
  74
  75                 case 'i':
  76                         device = optarg;
  77                         break;
  78
  79                 default:
  80                         usage();
  81                         /* NOTREACHED */
  82                 }
  83         }
  84
  85         if (device == NULL) {
  86                 device = pcap_lookupdev(ebuf);
  87                 if (device == NULL)
  88                         error("%s", ebuf);
  89         }
  90         *ebuf = '\0';
  91         pd = pcap_open_live(device, 65535, 0, 1000, ebuf);
  92         if (pd == NULL)
  93                 error("%s", ebuf);
  94         else if (*ebuf)
  95                 warning("%s", ebuf);
  96         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
  97                 localnet = 0;
  98                 netmask = 0;
  99                 warning("%s", ebuf);
 100         }
 101         cmdbuf = copy_argv(&argv[optind]);
 102
 103         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 104                 error("%s", pcap_geterr(pd));
 105
 106         if (pcap_setfilter(pd, &fcode) < 0)
 107                 error("%s", pcap_geterr(pd));
 108         if (pcap_setnonblock(pd, 1, ebuf) == -1)
 109                 error("pcap_setnonblock failed: %s", ebuf);
 110         printf("Listening on %s\n", device);
 111         for (;;) {
 112                 packet_count = 0;
 113                 status = pcap_dispatch(pd, -1, countme,
 114                     (u_char *)&packet_count);
 115                 if (status < 0)
 116                         break;
 117                 if (status != 0) {
 118                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 119                             status, packet_count);
 120                 }
 121         }
 122         if (status == -2) {
 123                 /*
 124                  * We got interrupted, so perhaps we didn't
 125                  * manage to finish a line we were printing.
 126                  * Print an extra newline, just in case.
 127                  */
 128                 putchar('\n');
 129         }
 130         (void)fflush(stdout);
 131         if (status == -1) {
 132                 /*
 133                  * Error.  Report it.
 134                  */
 135                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 136                     program_name, pcap_geterr(pd));
 137         }
 138         pcap_close(pd);
 139         exit(status == -1 ? 1 : 0);
 140 }
 141
 142 static void
 143 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 144 {
 145         int *counterp = (int *)user;
 146
 147         (*counterp)++;
 148 }
 149
 150 static void
 151 usage(void)
 152 {
 153         (void)fprintf(stderr, "Usage: %s [ -sptn ] [ -i interface ] [expression]\n",
 154             program_name);
 155         exit(1);
 156 }
 157
 158 /* VARARGS */
 159 static void
 160 error(const char *fmt, ...)
 161 {
 162         va_list ap;
 163
 164         (void)fprintf(stderr, "%s: ", program_name);
 165         va_start(ap, fmt);
 166         (void)vfprintf(stderr, fmt, ap);
 167         va_end(ap);
 168         if (*fmt) {
 169                 fmt += strlen(fmt);
 170                 if (fmt[-1] != '\n')
 171                         (void)fputc('\n', stderr);
 172         }
 173         exit(1);
 174         /* NOTREACHED */
 175 }
 176
 177 /* VARARGS */
 178 static void
 179 warning(const char *fmt, ...)
 180 {
 181         va_list ap;
 182
 183         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 184         va_start(ap, fmt);
 185         (void)vfprintf(stderr, fmt, ap);
 186         va_end(ap);
 187         if (*fmt) {
 188                 fmt += strlen(fmt);
 189                 if (fmt[-1] != '\n')
 190                         (void)fputc('\n', stderr);
 191         }
 192 }
 193
 194 /*
 195  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 196  */
 197 static char *
 198 copy_argv(register char **argv)
 199 {
 200         register char **p;
 201         register u_int len = 0;
 202         char *buf;
 203         char *src, *dst;
 204
 205         p = argv;
 206         if (*p == 0)
 207                 return 0;
 208
 209         while (*p)
 210                 len += strlen(*p++) + 1;
 211
 212         buf = (char *)malloc(len);
 213         if (buf == NULL)
 214                 error("copy_argv: malloc");
 215
 216         p = argv;
 217         dst = buf;
 218         while ((src = *p++) != NULL) {
 219                 while ((*dst++ = *src++) != '\0')
 220                         ;
 221                 dst[-1] = ' ';
 222         }
 223         dst[-1] = '\0';
 224
 225         return buf;
 226 }