src/src/os.c

   1 /* $Cambridge: exim/src/src/os.c,v 1.2 2005/01/04 10:00:42 ph10 Exp $ */
   2
   3 /*************************************************
   4 *     Exim - an Internet mail transport agent    *
   5 *************************************************/
   6
   7 /* Copyright (c) University of Cambridge 1995 - 2005 */
   8 /* See the file NOTICE for conditions of use and distribution. */
   9
  10 #ifdef STAND_ALONE
  11 #include <signal.h>
  12 #include <stdio.h>
  13 #include <time.h>
  14 #endif
  15
  16 /* This source file contains "default" system-dependent functions which
  17 provide functionality (or lack of it) in cases where the OS-specific os.c
  18 file has not. Some of them are tailored by macros defined in os.h files. */
  19
  20
  21 #ifndef OS_RESTARTING_SIGNAL
  22 /*************************************************
  23 *          Set up restarting signal              *
  24 *************************************************/
  25
  26 /* This function has the same functionality as the ANSI C signal() function,
  27 except that it arranges that, if the signal happens during a system call, the
  28 system call gets restarted. (Also, it doesn't return a result.) Different
  29 versions of Unix have different defaults, and different ways of setting up a
  30 restarting signal handler. If the functionality is not available, the signal
  31 should be set to be ignored. This function is used only for catching SIGUSR1.
  32 */
  33
  34 void
  35 os_restarting_signal(int sig, void (*handler)(int))
  36 {
  37 /* Many systems have the SA_RESTART sigaction for specifying that a signal
  38 should restart system calls. These include SunOS5, AIX, BSDI, IRIX, FreeBSD,
  39 OSF1, Linux and HP-UX 10 (but *not* HP-UX 9). */
  40
  41 #ifdef SA_RESTART
  42 struct sigaction act;
  43 act.sa_handler = handler;
  44 sigemptyset(&(act.sa_mask));
  45 act.sa_flags = SA_RESTART;
  46 sigaction(sig, &act, NULL);
  47
  48 #ifdef STAND_ALONE
  49 printf("Used SA_RESTART\n");
  50 #endif
  51
  52 /* SunOS4 and Ultrix default to non-interruptable signals, with SV_INTERRUPT
  53 for making them interruptable. This seems to be a dying fashion. */
  54
  55 #elif defined SV_INTERRUPT
  56 signal(sig, handler);
  57
  58 #ifdef STAND_ALONE
  59 printf("Used default signal()\n");
  60 #endif
  61
  62
  63 /* If neither SA_RESTART nor SV_INTERRUPT is available we don't know how to
  64 set up a restarting signal, so simply suppress the facility. */
  65
  66 #else
  67 signal(sig, SIG_IGN);
  68
  69 #ifdef STAND_ALONE
  70 printf("Used SIG_IGN\n");
  71 #endif
  72
  73 #endif
  74 }
  75
  76 #endif  /* OS_RESTARTING_SIGNAL */
  77
  78
  79 #ifndef OS_NON_RESTARTING_SIGNAL
  80 /*************************************************
  81 *          Set up non-restarting signal          *
  82 *************************************************/
  83
  84 /* This function has the same functionality as the ANSI C signal() function,
  85 except that it arranges that, if the signal happens during a system call, the
  86 system call gets interrupted. (Also, it doesn't return a result.) Different
  87 versions of Unix have different defaults, and different ways of setting up a
  88 non-restarting signal handler. For systems for which we don't know what to do,
  89 just use the normal signal() function and hope for the best. */
  90
  91 void
  92 os_non_restarting_signal(int sig, void (*handler)(int))
  93 {
  94 /* Many systems have the SA_RESTART sigaction for specifying that a signal
  95 should restart system calls. These include SunOS5, AIX, BSDI, IRIX, FreeBSD,
  96 OSF1, Linux and HP-UX 10 (but *not* HP-UX 9). */
  97
  98 #ifdef SA_RESTART
  99 struct sigaction act;
 100 act.sa_handler = handler;
 101 sigemptyset(&(act.sa_mask));
 102 act.sa_flags = 0;
 103 sigaction(sig, &act, NULL);
 104
 105 #ifdef STAND_ALONE
 106 printf("Used sigaction() with flags = 0\n");
 107 #endif
 108
 109 /* SunOS4 and Ultrix default to non-interruptable signals, with SV_INTERRUPT
 110 for making them interruptable. This seems to be a dying fashion. */
 111
 112 #elif defined SV_INTERRUPT
 113 struct sigvec sv;
 114 sv.sv_handler = handler;
 115 sv.sv_flags = SV_INTERRUPT;
 116 sv.sv_mask = -1;
 117 sigvec(sig, &sv, NULL);
 118
 119 #ifdef STAND_ALONE
 120 printf("Used sigvec() with flags = SV_INTERRUPT\n");
 121 #endif
 122
 123 /* If neither SA_RESTART nor SV_INTERRUPT is available we don't know how to
 124 set up a restarting signal, so just use the standard signal() function. */
 125
 126 #else
 127 signal(sig, handler);
 128
 129 #ifdef STAND_ALONE
 130 printf("Used default signal()\n");
 131 #endif
 132
 133 #endif
 134 }
 135
 136 #endif  /* OS_NON_RESTARTING_SIGNAL */
 137
 138
 139
 140 #ifdef STRERROR_FROM_ERRLIST
 141 /*************************************************
 142 *     Provide strerror() for non-ANSI libraries  *
 143 *************************************************/
 144
 145 /* Some old-fashioned systems still around (e.g. SunOS4) don't have strerror()
 146 in their libraries, but can provide the same facility by this simple
 147 alternative function. */
 148
 149 char *
 150 strerror(int n)
 151 {
 152 if (n < 0 || n >= sys_nerr) return "unknown error number";
 153 return sys_errlist[n];
 154 }
 155 #endif /* STRERROR_FROM_ERRLIST */
 156
 157
 158
 159 #ifndef OS_STRSIGNAL
 160 /*************************************************
 161 *      Provide strsignal() for systems without   *
 162 *************************************************/
 163
 164 /* Some systems have strsignal() to turn signal numbers into names; others
 165 may have other means of doing this. This function is used for those systems
 166 that have nothing. It provides a basic translation for the common standard
 167 signal numbers. I've been extra cautious with the ifdef's here. Probably more
 168 than is necessary... */
 169
 170 char *
 171 os_strsignal(int n)
 172 {
 173 switch (n)
 174   {
 175   #ifdef SIGHUP
 176   case SIGHUP:  return "hangup";
 177   #endif
 178
 179   #ifdef SIGINT
 180   case SIGINT:  return "interrupt";
 181   #endif
 182
 183   #ifdef SIGQUIT
 184   case SIGQUIT: return "quit";
 185   #endif
 186
 187   #ifdef SIGILL
 188   case SIGILL:  return "illegal instruction";
 189   #endif
 190
 191   #ifdef SIGTRAP
 192   case SIGTRAP: return "trace trap";
 193   #endif
 194
 195   #ifdef SIGABRT
 196   case SIGABRT: return "abort";
 197   #endif
 198
 199   #ifdef SIGEMT
 200   case SIGEMT:  return "EMT instruction";
 201   #endif
 202
 203   #ifdef SIGFPE
 204   case SIGFPE:  return "arithmetic exception";
 205   #endif
 206
 207   #ifdef SIGKILL
 208   case SIGKILL: return "killed";
 209   #endif
 210
 211   #ifdef SIGBUS
 212   case SIGBUS:  return "bus error";
 213   #endif
 214
 215   #ifdef SIGSEGV
 216   case SIGSEGV: return "segmentation fault";
 217   #endif
 218
 219   #ifdef SIGSYS
 220   case SIGSYS:  return "bad system call";
 221   #endif
 222
 223   #ifdef SIGPIPE
 224   case SIGPIPE: return "broken pipe";
 225   #endif
 226
 227   #ifdef SIGALRM
 228   case SIGALRM: return "alarm";
 229   #endif
 230
 231   #ifdef SIGTERM
 232   case SIGTERM: return "terminated";
 233   #endif
 234
 235   #ifdef SIGUSR1
 236   case SIGUSR1: return "user signal 1";
 237   #endif
 238
 239   #ifdef SIGUSR2
 240   case SIGUSR2: return "user signal 2";
 241   #endif
 242
 243   #ifdef SIGCHLD
 244   case SIGCHLD: return "child stop or exit";
 245   #endif
 246
 247   #ifdef SIGPWR
 248   case SIGPWR:  return "power fail/restart";
 249   #endif
 250
 251   #ifdef SIGURG
 252   case SIGURG:  return "urgent condition on I/O channel";
 253   #endif
 254
 255   #ifdef SIGSTOP
 256   case SIGSTOP: return "stop";
 257   #endif
 258
 259   #ifdef SIGTSTP
 260   case SIGTSTP: return "stop from tty";
 261   #endif
 262
 263   #ifdef SIGXCPU
 264   case SIGXCPU: return "exceeded CPU limit";
 265   #endif
 266
 267   #ifdef SIGXFSZ
 268   case SIGXFSZ: return "exceeded file size limit";
 269   #endif
 270
 271   default:      return "unrecognized signal number";
 272   }
 273 }
 274 #endif /* OS_STRSIGNAL */
 275
 276
 277
 278 #ifndef OS_STREXIT
 279 /*************************************************
 280 *      Provide strexit() for systems without     *
 281 *************************************************/
 282
 283 /* Actually, I don't know of any system that has a strexit() function to turn
 284 exit codes into text, but this function is implemented this way so that if any
 285 OS does have such a thing, it could be used instead of this build-in one. */
 286
 287 char *
 288 os_strexit(int n)
 289 {
 290 switch (n)
 291   {
 292   /* On systems without sysexits.h we can assume only those exit codes
 293   that are given a default value in exim.h. */
 294
 295   #ifndef NO_SYSEXITS
 296   case EX_USAGE:       return "(could mean usage or syntax error)";
 297   case EX_DATAERR:     return "(could mean error in input data)";
 298   case EX_NOINPUT:     return "(could mean input data missing)";
 299   case EX_NOUSER:      return "(could mean user nonexistent)";
 300   case EX_NOHOST:      return "(could mean host nonexistent)";
 301   case EX_SOFTWARE:    return "(could mean internal software error)";
 302   case EX_OSERR:       return "(could mean internal operating system error)";
 303   case EX_OSFILE:      return "(could mean system file missing)";
 304   case EX_IOERR:       return "(could mean input/output error)";
 305   case EX_PROTOCOL:    return "(could mean protocol error)";
 306   case EX_NOPERM:      return "(could mean permission denied)";
 307   #endif
 308
 309   case EX_EXECFAILED:  return "(could mean unable to exec or command does not exist)";
 310   case EX_UNAVAILABLE: return "(could mean service or program unavailable)";
 311   case EX_CANTCREAT:   return "(could mean can't create output file)";
 312   case EX_TEMPFAIL:    return "(could mean temporary error)";
 313   case EX_CONFIG:      return "(could mean configuration error)";
 314   default:             return "";
 315   }
 316 }
 317 #endif /* OS_STREXIT */
 318
 319
 320
 321
 322 /***********************************************************
 323 *                   Load average function                  *
 324 ***********************************************************/
 325
 326 /* Although every Unix seems to have a different way of getting the load
 327 average, a number of them have things in common. Some common variants are
 328 provided below, but if an OS has unique requirements it can be handled in
 329 a specific os.c file. What is required is a function called os_getloadavg
 330 which takes no arguments and passes back the load average * 1000 as an int,
 331 or -1 if no data is available. */
 332
 333
 334 /* ----------------------------------------------------------------------- */
 335 /* If the OS has got a BSD getloadavg() function, life is very easy. */
 336
 337 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_BSD_GETLOADAVG)
 338 #define OS_LOAD_AVERAGE
 339
 340 int
 341 os_getloadavg(void)
 342 {
 343 double avg;
 344 int loads = getloadavg (&avg, 1);
 345 if (loads != 1) return -1;
 346 return (int)(avg * 1000.0);
 347 }
 348 #endif
 349 /* ----------------------------------------------------------------------- */
 350
 351
 352
 353 /* ----------------------------------------------------------------------- */
 354 /* Only SunOS5 has the kstat functions as far as I know, but put the code
 355 here as there is the -hal variant, and other systems might follow this road one
 356 day. */
 357
 358 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_KSTAT)
 359 #define OS_LOAD_AVERAGE
 360
 361 #include <kstat.h>
 362
 363 int
 364 os_getloadavg(void)
 365 {
 366 int avg;
 367 kstat_ctl_t *kc;
 368 kstat_t *ksp;
 369 kstat_named_t *kn;
 370
 371 if ((kc = kstat_open()) == NULL ||
 372     (ksp = kstat_lookup(kc, LOAD_AVG_KSTAT_MODULE, 0, LOAD_AVG_KSTAT))
 373         == NULL ||
 374      kstat_read(kc, ksp, NULL) < 0 ||
 375     (kn = kstat_data_lookup(ksp, LOAD_AVG_SYMBOL)) == NULL)
 376   return -1;
 377
 378 avg = (int)(((double)(kn->LOAD_AVG_FIELD)/FSCALE) * 1000.0);
 379
 380 kstat_close(kc);
 381 return avg;
 382 }
 383
 384 #endif
 385 /* ----------------------------------------------------------------------- */
 386
 387
 388
 389 /* ----------------------------------------------------------------------- */
 390 /* Handle OS where a kernel symbol has to be read from /dev/kmem */
 391
 392 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_DEV_KMEM)
 393 #define OS_LOAD_AVERAGE
 394
 395 #include <nlist.h>
 396
 397 static int  avg_kd = -1;
 398 static long avg_offset;
 399
 400 int
 401 os_getloadavg(void)
 402 {
 403 LOAD_AVG_TYPE avg;
 404
 405 if (avg_kd < 0)
 406   {
 407   struct nlist nl[2];
 408   nl[0].n_name = LOAD_AVG_SYMBOL;
 409   nl[1].n_name = "";
 410   nlist (KERNEL_PATH, nl);
 411   avg_offset = (long)nl[0].n_value;
 412   avg_kd = open ("/dev/kmem", 0);
 413   if (avg_kd < 0) return -1;
 414   (void) fcntl(avg_kd, F_SETFD, FD_CLOEXEC);
 415   }
 416
 417 if (lseek (avg_kd, avg_offset, 0) == -1L
 418     || read (avg_kd, (char *)(&avg), sizeof (avg)) != sizeof(avg))
 419   return -1;
 420
 421 return (int)(((double)avg/FSCALE)*1000.0);
 422 }
 423
 424 #endif
 425 /* ----------------------------------------------------------------------- */
 426
 427
 428
 429 /* ----------------------------------------------------------------------- */
 430 /* If nothing is known about this OS, then the load average facility is
 431 not available. */
 432
 433 #ifndef OS_LOAD_AVERAGE
 434
 435 int
 436 os_getloadavg(void)
 437 {
 438 return -1;
 439 }
 440
 441 #endif
 442
 443 /* ----------------------------------------------------------------------- */
 444
 445
 446
 447 #if !defined FIND_RUNNING_INTERFACES
 448 /*************************************************
 449 *     Find all the running network interfaces    *
 450 *************************************************/
 451
 452 /* Finding all the running interfaces is something that has os-dependent
 453 tweaks, even in the IPv4 case, and it gets worse for IPv6, which is why this
 454 code is now in the os-dependent source file. There is a common function which
 455 works on most OS (except IRIX) for IPv4 interfaces, and, with some variations
 456 controlled by macros, on at least one OS for IPv6 and IPv4 interfaces. On Linux
 457 with IPv6, the common function is used for the IPv4 interfaces and additional
 458 code used for IPv6. Consequently, the real function is called
 459 os_common_find_running_interfaces() so that it can be called from the Linux
 460 function. On non-Linux systems, the macro for os_find_running_interfaces just
 461 calls the common function; on Linux it calls the Linux function.
 462
 463 This function finds the addresses of all the running interfaces on the machine.
 464 A chain of blocks containing the textual form of the addresses is returned.
 465
 466 Problems:
 467
 468   (1) Solaris 2 has the SIOGIFNUM call to get the number of interfaces, but
 469   other OS (including Solaris 1) appear not to. So just screw in a largeish
 470   fixed number, defined by MAX_INTERFACES. This is in the config.h file and
 471   can be changed in Local/Makefile. Unfortunately, the www addressing scheme
 472   means that some hosts have a very large number of virtual interfaces. Such
 473   hosts are recommended to set local_interfaces to avoid problems with this.
 474
 475   (2) If the standard code is run on IRIX, it does not return any alias
 476   interfaces. There is special purpose code for that operating system, which
 477   uses the sysctl() function. The code is in OS/os.c-IRIX, and this code isn't
 478   used on that OS.
 479
 480   (3) Some experimental/developing OS (e.g. GNU/Hurd) do not have any means
 481   of finding the interfaces. If NO_FIND_INTERFACES is set, a fudge-up is used
 482   instead.
 483
 484   (4) Some operating systems set the IP address in what SIOCGIFCONF returns;
 485   others do not, and require SIOCGIFADDR to be called to get it. For most of
 486   the former, calling the latter does no harm, but it causes grief on Linux and
 487   BSD systems in the case of IP aliasing, so a means of cutting it out is
 488   provided.
 489
 490 Arguments:    none
 491 Returns:      a chain of ip_address_items, each pointing to a textual
 492               version of an IP address, with the port field set to zero
 493 */
 494
 495
 496 #ifndef NO_FIND_INTERFACES
 497
 498 /* If there is IPv6 support, and SIOCGLIFCONF is defined, define macros to
 499 use these new, longer versions of the old IPv4 interfaces. Otherwise, define
 500 the macros to use the historical versions. */
 501
 502 #if HAVE_IPV6 && defined SIOCGLIFCONF
 503 #define V_ifconf        lifconf
 504 #define V_ifreq         lifreq
 505 #define V_GIFADDR       SIOCGLIFADDR
 506 #define V_GIFCONF       SIOCGLIFCONF
 507 #define V_GIFFLAGS      SIOCGLIFFLAGS
 508 #define V_ifc_buf       lifc_buf
 509 #define V_ifc_family    lifc_family
 510 #define V_ifc_flags     lifc_flags
 511 #define V_ifc_len       lifc_len
 512 #define V_ifr_addr      lifr_addr
 513 #define V_ifr_flags     lifr_flags
 514 #define V_ifr_name      lifr_name
 515 #define V_FAMILY_QUERY  AF_UNSPEC
 516 #define V_family        ss_family
 517 #else
 518 #define V_ifconf        ifconf
 519 #define V_ifreq         ifreq
 520 #define V_GIFADDR       SIOCGIFADDR
 521 #define V_GIFCONF       SIOCGIFCONF
 522 #define V_GIFFLAGS      SIOCGIFFLAGS
 523 #define V_ifc_buf       ifc_buf
 524 #define V_ifc_family    ifc_family
 525 #define V_ifc_flags     ifc_flags
 526 #define V_ifc_len       ifc_len
 527 #define V_ifr_addr      ifr_addr
 528 #define V_ifr_flags     ifr_flags
 529 #define V_ifr_name      ifr_name
 530 #define V_family        sa_family
 531 #endif
 532
 533 /* In all cases of IPv6 support, use an IPv6 socket. Otherwise (at least on
 534 Solaris 8) the call to read the flags doesn't work for IPv6 interfaces. If
 535 we find we can't actually make an IPv6 socket, the code will revert to trying
 536 an IPv4 socket. */
 537
 538 #if HAVE_IPV6
 539 #define FAMILY          AF_INET6
 540 #else
 541 #define FAMILY          AF_INET
 542 #endif
 543
 544 /* OK, after all that preliminary stuff, here's the code. */
 545
 546 ip_address_item *
 547 os_common_find_running_interfaces(void)
 548 {
 549 struct V_ifconf ifc;
 550 struct V_ifreq ifreq;
 551 int vs;
 552 ip_address_item *yield = NULL;
 553 ip_address_item *last = NULL;
 554 ip_address_item  *next;
 555 char *cp;
 556 char buf[MAX_INTERFACES*sizeof(struct V_ifreq)];
 557 struct sockaddr *addrp;
 558 size_t len = 0;
 559 char addrbuf[256];
 560
 561 /* We have to create a socket in order to do ioctls on it to find out
 562 what we want to know. */
 563
 564 if ((vs = socket(FAMILY, SOCK_DGRAM, 0)) < 0)
 565   {
 566   #if HAVE_IPV6
 567   DEBUG(D_interface)
 568     debug_printf("Unable to create IPv6 socket to find interface addresses:\n  "
 569       "error %d %s\nTrying for an IPv4 socket\n", errno, strerror(errno));
 570   vs = socket(AF_INET, SOCK_DGRAM, 0);
 571   if (vs < 0)
 572   #endif
 573   log_write(0, LOG_PANIC_DIE, "Unable to create IPv4 socket to find interface "
 574     "addresses: %d %s", errno, strerror(errno));
 575   }
 576
 577 /* Get the interface configuration. Some additional data is required when the
 578 new structures are in use. */
 579
 580 ifc.V_ifc_len = sizeof(buf);
 581 ifc.V_ifc_buf = buf;
 582
 583 #ifdef V_FAMILY_QUERY
 584 ifc.V_ifc_family = V_FAMILY_QUERY;
 585 ifc.V_ifc_flags = 0;
 586 #endif
 587
 588 if (ioctl(vs, V_GIFCONF, (char *)&ifc) < 0)
 589   log_write(0, LOG_PANIC_DIE, "Unable to get interface configuration: %d %s",
 590     errno, strerror(errno));
 591
 592 /* If the buffer is big enough, the ioctl sets the value of ifc.V_ifc_len to
 593 the amount actually used. If the buffer isn't big enough, at least on some
 594 operating systems, ifc.V_ifc_len still gets set to correspond to the total
 595 number of interfaces, even though they don't all fit in the buffer. */
 596
 597 if (ifc.V_ifc_len > sizeof(buf))
 598   {
 599   ifc.V_ifc_len = sizeof(buf);
 600   DEBUG(D_interface)
 601     debug_printf("more than %d interfaces found: remainder not used\n"
 602       "(set MAX_INTERFACES in Local/Makefile and rebuild if you want more)\n",
 603       MAX_INTERFACES);
 604   }
 605
 606 /* For each interface, check it is an IP interface, get its flags, and see if
 607 it is up; if not, skip.
 608
 609 BSD systems differ from others in what SIOCGIFCONF returns. Other systems
 610 return a vector of ifreq structures whose size is as defined by the structure.
 611 BSD systems allow sockaddrs to be longer than their sizeof, which in turn makes
 612 the ifreq structures longer than their sizeof. The code below has its origins
 613 in amd and ifconfig; it uses the sa_len field of each sockaddr to determine
 614 each item's length.
 615
 616 This is complicated by the fact that, at least on BSD systems, the data in the
 617 buffer is not guaranteed to be aligned. Thus, we must first copy the basic
 618 struct to some aligned memory before looking at the field in the fixed part to
 619 find its length, and then recopy the correct length. */
 620
 621 for (cp = buf; cp < buf + ifc.V_ifc_len; cp += len)
 622   {
 623   memcpy((char *)&ifreq, cp, sizeof(ifreq));
 624
 625   #ifndef HAVE_SA_LEN
 626   len = sizeof(struct V_ifreq);
 627
 628   #else
 629   len = ((ifreq.ifr_addr.sa_len > sizeof(ifreq.ifr_addr))?
 630           ifreq.ifr_addr.sa_len : sizeof(ifreq.ifr_addr)) +
 631          sizeof(ifreq.V_ifr_name);
 632   if (len > sizeof(addrbuf))
 633     log_write(0, LOG_PANIC_DIE, "Address for %s interface is absurdly long",
 634         ifreq.V_ifr_name);
 635
 636   #endif
 637
 638   /* If not an IP interface, skip */
 639
 640   if (ifreq.V_ifr_addr.V_family != AF_INET
 641   #if HAVE_IPV6
 642     && ifreq.V_ifr_addr.V_family != AF_INET6
 643   #endif
 644     ) continue;
 645
 646   /* Get the interface flags, and if the interface is down, continue. Formerly,
 647   we treated the inability to get the flags as a panic-die error. However, it
 648   seems that on some OS (Solaris 9 being the case noted), it is possible to
 649   have an interface in this list for which this call fails because the
 650   interface hasn't been "plumbed" to any protocol (IPv4 or IPv6). Therefore,
 651   we now just treat this case as "down" as well. */
 652
 653   if (ioctl(vs, V_GIFFLAGS, (char *)&ifreq) < 0)
 654     {
 655     continue;
 656     /*************
 657     log_write(0, LOG_PANIC_DIE, "Unable to get flags for %s interface: %d %s",
 658       ifreq.V_ifr_name, errno, strerror(errno));
 659     *************/
 660     }
 661   if ((ifreq.V_ifr_flags & IFF_UP) == 0) continue;
 662
 663   /* On some operating systems we have to get the IP address of the interface
 664   by another call. On others, it's already there, but we must reinstate the
 665   data in ifreq, because SIOCGIFFLAGS may wreck it. */
 666
 667   #ifndef SIOCGIFCONF_GIVES_ADDR
 668   if (ioctl(vs, V_GIFADDR, (char *)&ifreq) < 0)
 669     log_write(0, LOG_PANIC_DIE, "Unable to get IP address for %s interface: "
 670       "%d %s", ifreq.V_ifr_name, errno, strerror(errno));
 671   addrp = &ifreq.V_ifr_addr;
 672
 673   #else
 674   memcpy((char *)&ifreq, cp, sizeof(ifreq));
 675   memcpy(addrbuf, (char *)&(ifreq.V_ifr_addr), len - sizeof(ifreq.V_ifr_name));
 676   addrp = (struct sockaddr *)addrbuf;
 677   #endif
 678
 679   /* Create a data block for the address, fill in the data, and put it on the
 680   chain. */
 681
 682   next = store_get(sizeof(ip_address_item));
 683   next->next = NULL;
 684   next->port = 0;
 685   (void)host_ntoa(-1, addrp, next->address, NULL);
 686
 687   if (yield == NULL) yield = last = next; else
 688     {
 689     last->next = next;
 690     last = next;
 691     }
 692
 693   DEBUG(D_interface) debug_printf("Actual local interface address is %s (%s)\n",
 694     last->address, ifreq.V_ifr_name);
 695   }
 696
 697 /* Close the socket, and return the chain of data blocks. */
 698
 699 close(vs);
 700 return yield;
 701 }
 702
 703 #else  /* NO_FIND_INTERFACES */
 704
 705 /* Some experimental or developing OS (e.g. GNU/Hurd) do not have the ioctls,
 706 and there is no other way to get a list of the (IP addresses of) local
 707 interfaces. We just return the loopback address(es). */
 708
 709 ip_address_item *
 710 os_common_find_running_interfaces(void)
 711 {
 712 ip_address_item *yield = store_get(sizeof(address_item));
 713 yield->address = US"127.0.0.1";
 714 yield->port = 0;
 715 yield->next = NULL;
 716
 717 #if HAVE_IPV6
 718 yield->next = store_get(sizeof(address_item));
 719 yield->next->address = US"::1";
 720 yield->next->port = 0;
 721 yield->next->next = NULL;
 722 #endif
 723
 724 DEBUG(D_interface) debug_printf("Unable to find local interface addresses "
 725   "on this OS: returning loopback address(es)\n");
 726 return yield;
 727 }
 728
 729 #endif /* NO_FIND_INTERFACES */
 730 #endif /* FIND_RUNNING_INTERFACES */
 731
 732
 733
 734
 735
 736 /*************************************************
 737 **************************************************
 738 *             Stand-alone test program           *
 739 **************************************************
 740 *************************************************/
 741
 742
 743 #ifdef STAND_ALONE
 744
 745 #ifdef CLOCKS_PER_SEC
 746 #define REAL_CLOCK_TICK CLOCKS_PER_SEC
 747 #else
 748   #ifdef CLK_TCK
 749   #define REAL_CLOCK_TICK CLK_TCK
 750   #else
 751   #define REAL_CLOCK_TICK 1000000   /* SunOS4 */
 752   #endif
 753 #endif
 754
 755
 756 int main(int argc, char **argv)
 757 {
 758 char buffer[128];
 759 int fd = fileno(stdin);
 760 int rc;
 761
 762 printf("Testing restarting signal; wait for handler message, then type a line\n");
 763 strcpy(buffer, "*** default ***\n");
 764 os_restarting_signal(SIGALRM, sigalrm_handler);
 765 alarm(2);
 766 if ((rc = read(fd, buffer, sizeof(buffer))) < 0)
 767   printf("No data read\n");
 768 else
 769   {
 770   buffer[rc] = 0;
 771   printf("Read: %s", buffer);
 772   }
 773 alarm(0);
 774
 775 printf("Testing non-restarting signal; should read no data after handler message\n");
 776 strcpy(buffer, "*** default ***\n");
 777 os_non_restarting_signal(SIGALRM, sigalrm_handler);
 778 alarm(2);
 779 if ((rc = read(fd, buffer, sizeof(buffer))) < 0)
 780   printf("No data read\n");
 781 else
 782   {
 783   buffer[rc] = 0;
 784   printf("Read: %s", buffer);
 785   }
 786 alarm(0);
 787
 788 printf("Testing load averages (last test - ^C to kill)\n");
 789 for (;;)
 790   {
 791   int avg;
 792   clock_t used;
 793   clock_t before = clock();
 794   avg = os_getloadavg();
 795   used = clock() - before;
 796   printf("cpu time = %.2f ", (double)used/REAL_CLOCK_TICK);
 797   if (avg < 0)
 798     {
 799     printf("load average not available\n");
 800     break;
 801     }
 802   printf("load average = %.2f\n", (double)avg/1000.0);
 803   sleep(2);
 804   }
 805 return 0;
 806 }
 807
 808 #endif
 809
 810 /* End of os.c */