The Tcpdump Group git mirrors - libpcap/blob - testprogs/threadsignaltest.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 #include "varattrs.h"
  23
  24 #ifndef lint
  25 static const char copyright[] _U_ =
  26     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
  27 The Regents of the University of California.  All rights reserved.\n";
  28 #endif
  29
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <stdarg.h>
  34 #include <limits.h>
  35 #ifdef _WIN32
  36   #include <winsock2.h>
  37   #include <windows.h>
  38
  39   #define THREAD_HANDLE                 HANDLE
  40   #define THREAD_FUNC_ARG_TYPE          LPVOID
  41   #define THREAD_FUNC_RETURN_TYPE       DWORD __stdcall
  42
  43   #include "getopt.h"
  44 #else
  45   #include <pthread.h>
  46   #include <signal.h>
  47   #include <unistd.h>
  48
  49   #define THREAD_HANDLE                 pthread_t
  50   #define THREAD_FUNC_ARG_TYPE          void *
  51   #define THREAD_FUNC_RETURN_TYPE       void *
  52 #endif
  53 #include <errno.h>
  54 #include <sys/types.h>
  55
  56 #include <pcap.h>
  57
  58 #include "pcap/funcattrs.h"
  59
  60 #ifdef _WIN32
  61   #include "portability.h"
  62 #endif
  63
  64 static char *program_name;
  65
  66 /* Forwards */
  67 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  68 static void PCAP_NORETURN usage(void);
  69 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  70 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  71 static char *copy_argv(char **);
  72
  73 static pcap_t *pd;
  74
  75 #ifdef _WIN32
  76 /*
  77  * Generate a string for a Win32-specific error (i.e. an error generated when
  78  * calling a Win32 API).
  79  * For errors occurred during standard C calls, we still use pcap_strerror()
  80  */
  81 #define ERRBUF_SIZE     1024
  82 static const char *
  83 win32_strerror(DWORD error)
  84 {
  85   static char errbuf[ERRBUF_SIZE+1];
  86   size_t errlen;
  87
  88   FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
  89                 ERRBUF_SIZE, NULL);
  90
  91   /*
  92    * "FormatMessage()" "helpfully" sticks CR/LF at the end of the
  93    * message.  Get rid of it.
  94    */
  95   errlen = strlen(errbuf);
  96   if (errlen >= 2) {
  97     errbuf[errlen - 1] = '\0';
  98     errbuf[errlen - 2] = '\0';
  99     errlen -= 2;
 100   }
 101   return errbuf;
 102 }
 103 #else
 104 static void
 105 catch_sigusr1(int sig _U_)
 106 {
 107         printf("Got SIGUSR1\n");
 108 }
 109 #endif
 110
 111 static void
 112 sleep_secs(int secs)
 113 {
 114 #ifdef _WIN32
 115         Sleep(secs*1000);
 116 #else
 117         unsigned secs_remaining;
 118
 119         if (secs <= 0)
 120                 return;
 121         secs_remaining = secs;
 122         while (secs_remaining != 0)
 123                 secs_remaining = sleep(secs_remaining);
 124 #endif
 125 }
 126
 127 static THREAD_FUNC_RETURN_TYPE
 128 capture_thread_func(THREAD_FUNC_ARG_TYPE arg)
 129 {
 130         char *device = arg;
 131         int packet_count;
 132         int status;
 133 #ifndef _WIN32
 134         struct sigaction action;
 135         sigset_t mask;
 136 #endif
 137
 138 #ifndef _WIN32
 139         sigemptyset(&mask);
 140         action.sa_handler = catch_sigusr1;
 141         action.sa_mask = mask;
 142         action.sa_flags = 0;
 143         if (sigaction(SIGUSR1, &action, NULL) == -1)
 144                 error("Can't catch SIGUSR1: %s", strerror(errno));
 145 #endif
 146
 147         printf("Listening on %s\n", device);
 148         for (;;) {
 149                 packet_count = 0;
 150                 status = pcap_dispatch(pd, -1, countme,
 151                     (u_char *)&packet_count);
 152                 if (status < 0)
 153                         break;
 154                 if (status != 0) {
 155                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 156                             status, packet_count);
 157                 } else
 158                         printf("No packets seen by pcap_dispatch\n");
 159         }
 160         if (status == PCAP_ERROR_BREAK) {
 161                 /*
 162                  * We got interrupted, so perhaps we didn't
 163                  * manage to finish a line we were printing.
 164                  * Print an extra newline, just in case.
 165                  */
 166                 putchar('\n');
 167                 printf("Loop got broken\n");
 168         }
 169         (void)fflush(stdout);
 170         if (status == PCAP_ERROR) {
 171                 /*
 172                  * Error.  Report it.
 173                  */
 174                 (void)fprintf(stderr, "%s: pcap_dispatch: %s\n",
 175                     program_name, pcap_geterr(pd));
 176         }
 177         return 0;
 178 }
 179
 180 int
 181 main(int argc, char **argv)
 182 {
 183         register int op;
 184         register char *cp, *cmdbuf, *device;
 185         int do_wakeup = 1;
 186         pcap_if_t *devlist;
 187         bpf_u_int32 localnet, netmask;
 188         struct bpf_program fcode;
 189         char ebuf[PCAP_ERRBUF_SIZE];
 190         int status;
 191         THREAD_HANDLE capture_thread;
 192 #ifndef _WIN32
 193         void *retval;
 194 #endif
 195
 196         device = NULL;
 197         if ((cp = strrchr(argv[0], '/')) != NULL)
 198                 program_name = cp + 1;
 199         else
 200                 program_name = argv[0];
 201
 202         opterr = 0;
 203         while ((op = getopt(argc, argv, "i:n")) != -1) {
 204                 switch (op) {
 205
 206                 case 'i':
 207                         device = optarg;
 208                         break;
 209
 210                 case 'n':
 211                         do_wakeup = 0;
 212                         break;
 213
 214                 default:
 215                         usage();
 216                         /* NOTREACHED */
 217                 }
 218         }
 219
 220         if (device == NULL) {
 221                 if (pcap_findalldevs(&devlist, ebuf) == -1)
 222                         error("%s", ebuf);
 223                 if (devlist == NULL)
 224                         error("no interfaces available for capture");
 225                 device = strdup(devlist->name);
 226                 pcap_freealldevs(devlist);
 227         }
 228         *ebuf = '\0';
 229         pd = pcap_create(device, ebuf);
 230         if (pd == NULL)
 231                 error("%s", ebuf);
 232         status = pcap_set_snaplen(pd, 65535);
 233         if (status != 0)
 234                 error("%s: pcap_set_snaplen failed: %s",
 235                             device, pcap_statustostr(status));
 236         status = pcap_set_timeout(pd, 5*60*1000);
 237         if (status != 0)
 238                 error("%s: pcap_set_timeout failed: %s",
 239                     device, pcap_statustostr(status));
 240         status = pcap_activate(pd);
 241         if (status < 0) {
 242                 /*
 243                  * pcap_activate() failed.
 244                  */
 245                 error("%s: %s\n(%s)", device,
 246                     pcap_statustostr(status), pcap_geterr(pd));
 247         } else if (status > 0) {
 248                 /*
 249                  * pcap_activate() succeeded, but it's warning us
 250                  * of a problem it had.
 251                  */
 252                 warning("%s: %s\n(%s)", device,
 253                     pcap_statustostr(status), pcap_geterr(pd));
 254         }
 255         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 256                 localnet = 0;
 257                 netmask = 0;
 258                 warning("%s", ebuf);
 259         }
 260         cmdbuf = copy_argv(&argv[optind]);
 261
 262         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 263                 error("%s", pcap_geterr(pd));
 264
 265         if (pcap_setfilter(pd, &fcode) < 0)
 266                 error("%s", pcap_geterr(pd));
 267
 268 #ifdef _WIN32
 269         capture_thread = CreateThread(NULL, 0, capture_thread_func, device,
 270             0, NULL);
 271         if (capture_thread == NULL)
 272                 error("Can't create capture thread: %s",
 273                     win32_strerror(GetLastError()));
 274 #else
 275         status = pthread_create(&capture_thread, NULL, capture_thread_func,
 276             device);
 277         if (status != 0)
 278                 error("Can't create capture thread: %s", strerror(status));
 279 #endif
 280         sleep_secs(60);
 281         printf("Doing pcap_breakloop()\n");
 282         pcap_breakloop(pd);
 283         if (do_wakeup) {
 284                 /*
 285                  * Force a wakeup in the capture thread.
 286                  *
 287                  * On some platforms, with some devices,, pcap_breakloop()
 288                  * can't do that itself.  On Windows, poke the device's
 289                  * event handle; on UN*X, send a SIGUSR1 to the thread.
 290                  */
 291 #ifdef _WIN32
 292                 printf("Setting event\n");
 293                 if (!SetEvent(pcap_getevent(pd)))
 294                         error("Can't set event for pcap_t: %s",
 295                             win32_strerror(GetLastError()));
 296 #else
 297                 printf("Sending SIGUSR1\n");
 298                 status = pthread_kill(capture_thread, SIGUSR1);
 299                 if (status != 0)
 300                         warning("Can't interrupt capture thread: %s",
 301                         strerror(status));
 302 #endif
 303         }
 304
 305         /*
 306          * Now wait for the capture thread to terminate.
 307          */
 308 #ifdef _WIN32
 309         if (WaitForSingleObject(capture_thread, INFINITE) == WAIT_FAILED)
 310                 error("Wait for thread termination failed: %s",
 311                     win32_strerror(GetLastError()));
 312         CloseHandle(capture_thread);
 313 #else
 314         status = pthread_join(capture_thread, &retval);
 315         if (status != 0)
 316                 error("Wait for thread termination failed: %s",
 317                     strerror(status));
 318 #endif
 319
 320         pcap_close(pd);
 321         pcap_freecode(&fcode);
 322         exit(status == -1 ? 1 : 0);
 323 }
 324
 325 static void
 326 countme(u_char *user, const struct pcap_pkthdr *h _U_, const u_char *sp _U_)
 327 {
 328         int *counterp = (int *)user;
 329
 330         (*counterp)++;
 331 }
 332
 333 static void
 334 usage(void)
 335 {
 336         (void)fprintf(stderr, "Usage: %s [ -n ] [ -i interface ] [ expression ]\n",
 337             program_name);
 338         exit(1);
 339 }
 340
 341 /* VARARGS */
 342 static void
 343 error(const char *fmt, ...)
 344 {
 345         va_list ap;
 346
 347         (void)fprintf(stderr, "%s: ", program_name);
 348         va_start(ap, fmt);
 349         (void)vfprintf(stderr, fmt, ap);
 350         va_end(ap);
 351         if (*fmt) {
 352                 fmt += strlen(fmt);
 353                 if (fmt[-1] != '\n')
 354                         (void)fputc('\n', stderr);
 355         }
 356         exit(1);
 357         /* NOTREACHED */
 358 }
 359
 360 /* VARARGS */
 361 static void
 362 warning(const char *fmt, ...)
 363 {
 364         va_list ap;
 365
 366         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 367         va_start(ap, fmt);
 368         (void)vfprintf(stderr, fmt, ap);
 369         va_end(ap);
 370         if (*fmt) {
 371                 fmt += strlen(fmt);
 372                 if (fmt[-1] != '\n')
 373                         (void)fputc('\n', stderr);
 374         }
 375 }
 376
 377 /*
 378  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 379  */
 380 static char *
 381 copy_argv(register char **argv)
 382 {
 383         register char **p;
 384         register size_t len = 0;
 385         char *buf;
 386         char *src, *dst;
 387
 388         p = argv;
 389         if (*p == 0)
 390                 return 0;
 391
 392         while (*p)
 393                 len += strlen(*p++) + 1;
 394
 395         buf = (char *)malloc(len);
 396         if (buf == NULL)
 397                 error("copy_argv: malloc");
 398
 399         p = argv;
 400         dst = buf;
 401         while ((src = *p++) != NULL) {
 402                 while ((*dst++ = *src++) != '\0')
 403                         ;
 404                 dst[-1] = ' ';
 405         }
 406         dst[-1] = '\0';
 407
 408         return buf;
 409 }