getloadavg.c

   1 /* Get the system load averages.
   2    Copyright (C) 1985, 86, 87, 88, 89, 91, 92, 93, 1994, 1995, 1997
   3         Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  18    USA.  */
  19
  20 /* Compile-time symbols that this file uses:
  21
  22    HAVE_PSTAT_GETDYNAMIC        Define this if your system has the
  23                                 pstat_getdynamic function.  I think it
  24                                 is unique to HPUX9.  The best way to get the
  25                                 definition is through the AC_FUNC_GETLOADAVG
  26                                 macro that comes with autoconf 2.13 or newer.
  27                                 If that isn't an option, then just put
  28                                 AC_CHECK_FUNCS(pstat_getdynamic) in your
  29                                 configure.in file.
  30    FIXUP_KERNEL_SYMBOL_ADDR()   Adjust address in returned struct nlist.
  31    KERNEL_FILE                  Pathname of the kernel to nlist.
  32    LDAV_CVT()                   Scale the load average from the kernel.
  33                                 Returns a double.
  34    LDAV_SYMBOL                  Name of kernel symbol giving load average.
  35    LOAD_AVE_TYPE                Type of the load average array in the kernel.
  36                                 Must be defined unless one of
  37                                 apollo, DGUX, NeXT, or UMAX is defined;
  38                                 or we have libkstat;
  39                                 otherwise, no load average is available.
  40    NLIST_STRUCT                 Include nlist.h, not a.out.h, and
  41                                 the nlist n_name element is a pointer,
  42                                 not an array.
  43    HAVE_STRUCT_NLIST_N_UN_N_NAME struct nlist has an n_un member, not n_name.
  44    LINUX_LDAV_FILE              [__linux__]: File containing load averages.
  45
  46    Specific system predefines this file uses, aside from setting
  47    default values if not emacs:
  48
  49    apollo
  50    BSD                          Real BSD, not just BSD-like.
  51    convex
  52    DGUX
  53    eunice                       UNIX emulator under VMS.
  54    hpux
  55    __MSDOS__                    No-op for MSDOS.
  56    NeXT
  57    sgi
  58    sequent                      Sequent Dynix 3.x.x (BSD)
  59    _SEQUENT_                    Sequent DYNIX/ptx 1.x.x (SYSV)
  60    sony_news                    NEWS-OS (works at least for 4.1C)
  61    UMAX
  62    UMAX4_3
  63    VMS
  64    WINDOWS32                    No-op for Windows95/NT.
  65    __linux__                    Linux: assumes /proc filesystem mounted.
  66                                 Support from Michael K. Johnson.
  67    __NetBSD__                   NetBSD: assumes /kern filesystem mounted.
  68
  69    In addition, to avoid nesting many #ifdefs, we internally set
  70    LDAV_DONE to indicate that the load average has been computed.
  71
  72    We also #define LDAV_PRIVILEGED if a program will require
  73    special installation to be able to call getloadavg.  */
  74
  75 /* This should always be first.  */
  76 #ifdef HAVE_CONFIG_H
  77 # include <config.h>
  78 #endif
  79
  80 #include <sys/types.h>
  81
  82 /* Both the Emacs and non-Emacs sections want this.  Some
  83    configuration files' definitions for the LOAD_AVE_CVT macro (like
  84    sparc.h's) use macros like FSCALE, defined here.  */
  85 #if defined (unix) || defined (__unix)
  86 # include <sys/param.h>
  87 #endif
  88
  89
  90 /* Exclude all the code except the test program at the end
  91    if the system has its own `getloadavg' function.
  92
  93    The declaration of `errno' is needed by the test program
  94    as well as the function itself, so it comes first.  */
  95
  96 #include <errno.h>
  97
  98 #ifndef errno
  99 extern int errno;
 100 #endif
 101
 102 #if HAVE_LOCALE_H
 103 # include <locale.h>
 104 #endif
 105 #if !HAVE_SETLOCALE
 106 # define setlocale(Category, Locale) /* empty */
 107 #endif
 108
 109 #ifndef HAVE_GETLOADAVG
 110
 111
 112 /* The existing Emacs configuration files define a macro called
 113    LOAD_AVE_CVT, which accepts a value of type LOAD_AVE_TYPE, and
 114    returns the load average multiplied by 100.  What we actually want
 115    is a macro called LDAV_CVT, which returns the load average as an
 116    unmultiplied double.
 117
 118    For backwards compatibility, we'll define LDAV_CVT in terms of
 119    LOAD_AVE_CVT, but future machine config files should just define
 120    LDAV_CVT directly.  */
 121
 122 # if !defined(LDAV_CVT) && defined(LOAD_AVE_CVT)
 123 #  define LDAV_CVT(n) (LOAD_AVE_CVT (n) / 100.0)
 124 # endif
 125
 126 # if !defined (BSD) && defined (ultrix)
 127 /* Ultrix behaves like BSD on Vaxen.  */
 128 #  define BSD
 129 # endif
 130
 131 # ifdef NeXT
 132 /* NeXT in the 2.{0,1,2} releases defines BSD in <sys/param.h>, which
 133    conflicts with the definition understood in this file, that this
 134    really is BSD. */
 135 #  undef BSD
 136
 137 /* NeXT defines FSCALE in <sys/param.h>.  However, we take FSCALE being
 138    defined to mean that the nlist method should be used, which is not true.  */
 139 #  undef FSCALE
 140 # endif
 141
 142 /* Same issues as for NeXT apply to the HURD-based GNU system.  */
 143 # ifdef __GNU__
 144 #  undef BSD
 145 #  undef FSCALE
 146 # endif /* __GNU__ */
 147
 148 /* Set values that are different from the defaults, which are
 149    set a little farther down with #ifndef.  */
 150
 151
 152 /* Some shorthands.  */
 153
 154 # if defined (HPUX) && !defined (hpux)
 155 #  define hpux
 156 # endif
 157
 158 # if defined (__hpux) && !defined (hpux)
 159 #  define hpux
 160 # endif
 161
 162 # if defined (__sun) && !defined (sun)
 163 #  define sun
 164 # endif
 165
 166 # if defined(hp300) && !defined(hpux)
 167 #  define MORE_BSD
 168 # endif
 169
 170 # if defined(ultrix) && defined(mips)
 171 #  define decstation
 172 # endif
 173
 174 # if defined (__SVR4) && !defined (SVR4)
 175 #  define SVR4
 176 # endif
 177
 178 # if (defined(sun) && defined(SVR4)) || defined (SOLARIS2)
 179 #  define SUNOS_5
 180 # endif
 181
 182 # if defined (__osf__) && (defined (__alpha) || defined (__alpha__))
 183 #  define OSF_ALPHA
 184 #  include <sys/mbuf.h>
 185 #  include <sys/socket.h>
 186 #  include <net/route.h>
 187 #  include <sys/table.h>
 188 # endif
 189
 190 # if defined (__osf__) && (defined (mips) || defined (__mips__))
 191 #  define OSF_MIPS
 192 #  include <sys/table.h>
 193 # endif
 194
 195 /* UTek's /bin/cc on the 4300 has no architecture specific cpp define by
 196    default, but _MACH_IND_SYS_TYPES is defined in <sys/types.h>.  Combine
 197    that with a couple of other things and we'll have a unique match.  */
 198 # if !defined (tek4300) && defined (unix) && defined (m68k) && defined (mc68000) && defined (mc68020) && defined (_MACH_IND_SYS_TYPES)
 199 #  define tek4300                       /* Define by emacs, but not by other users.  */
 200 # endif
 201
 202 /* AC_FUNC_GETLOADAVG thinks QNX is SVR4, but it isn't. */
 203 # if defined(__QNX__)
 204 #  undef SVR4
 205 # endif
 206
 207 /* VAX C can't handle multi-line #ifs, or lines longer than 256 chars.  */
 208 # ifndef LOAD_AVE_TYPE
 209
 210 #  ifdef MORE_BSD
 211 #   define LOAD_AVE_TYPE long
 212 #  endif
 213
 214 #  ifdef sun
 215 #   define LOAD_AVE_TYPE long
 216 #  endif
 217
 218 #  ifdef decstation
 219 #   define LOAD_AVE_TYPE long
 220 #  endif
 221
 222 #  ifdef _SEQUENT_
 223 #   define LOAD_AVE_TYPE long
 224 #  endif
 225
 226 #  ifdef sgi
 227 #   define LOAD_AVE_TYPE long
 228 #  endif
 229
 230 #  ifdef SVR4
 231 #   define LOAD_AVE_TYPE long
 232 #  endif
 233
 234 #  ifdef sony_news
 235 #   define LOAD_AVE_TYPE long
 236 #  endif
 237
 238 #  ifdef sequent
 239 #   define LOAD_AVE_TYPE long
 240 #  endif
 241
 242 #  ifdef OSF_ALPHA
 243 #   define LOAD_AVE_TYPE long
 244 #  endif
 245
 246 #  if defined (ardent) && defined (titan)
 247 #   define LOAD_AVE_TYPE long
 248 #  endif
 249
 250 #  ifdef tek4300
 251 #   define LOAD_AVE_TYPE long
 252 #  endif
 253
 254 #  if defined(alliant) && defined(i860) /* Alliant FX/2800 */
 255 #   define LOAD_AVE_TYPE long
 256 #  endif
 257
 258 #  ifdef _AIX
 259 #   define LOAD_AVE_TYPE long
 260 #  endif
 261
 262 #  ifdef convex
 263 #   define LOAD_AVE_TYPE double
 264 #   ifndef LDAV_CVT
 265 #    define LDAV_CVT(n) (n)
 266 #   endif
 267 #  endif
 268
 269 # endif /* No LOAD_AVE_TYPE.  */
 270
 271 # ifdef OSF_ALPHA
 272 /* <sys/param.h> defines an incorrect value for FSCALE on Alpha OSF/1,
 273    according to ghazi@noc.rutgers.edu.  */
 274 #  undef FSCALE
 275 #  define FSCALE 1024.0
 276 # endif
 277
 278 # if defined(alliant) && defined(i860) /* Alliant FX/2800 */
 279 /* <sys/param.h> defines an incorrect value for FSCALE on an
 280    Alliant FX/2800 Concentrix 2.2, according to ghazi@noc.rutgers.edu.  */
 281 #  undef FSCALE
 282 #  define FSCALE 100.0
 283 # endif
 284
 285
 286 # ifndef        FSCALE
 287
 288 /* SunOS and some others define FSCALE in sys/param.h.  */
 289
 290 #  ifdef MORE_BSD
 291 #   define FSCALE 2048.0
 292 #  endif
 293
 294 #  if defined(MIPS) || defined(SVR4) || defined(decstation)
 295 #   define FSCALE 256
 296 #  endif
 297
 298 #  if defined (sgi) || defined (sequent)
 299 /* Sometimes both MIPS and sgi are defined, so FSCALE was just defined
 300    above under #ifdef MIPS.  But we want the sgi value.  */
 301 #   undef FSCALE
 302 #   define      FSCALE 1000.0
 303 #  endif
 304
 305 #  if defined (ardent) && defined (titan)
 306 #   define FSCALE 65536.0
 307 #  endif
 308
 309 #  ifdef tek4300
 310 #   define FSCALE 100.0
 311 #  endif
 312
 313 #  ifdef _AIX
 314 #   define FSCALE 65536.0
 315 #  endif
 316
 317 # endif /* Not FSCALE.  */
 318
 319 # if !defined (LDAV_CVT) && defined (FSCALE)
 320 #  define       LDAV_CVT(n) (((double) (n)) / FSCALE)
 321 # endif
 322
 323
 324 # if defined(sgi) || (defined(mips) && !defined(BSD))
 325 #  define FIXUP_KERNEL_SYMBOL_ADDR(nl) ((nl)[0].n_value &= ~(1 << 31))
 326 # endif
 327
 328
 329 # if !defined (KERNEL_FILE) && defined (sequent)
 330 #  define KERNEL_FILE "/dynix"
 331 # endif
 332
 333 # if !defined (KERNEL_FILE) && defined (hpux)
 334 #  define KERNEL_FILE "/hp-ux"
 335 # endif
 336
 337 # if !defined(KERNEL_FILE) && (defined(_SEQUENT_) || defined(MIPS) || defined(SVR4) || defined(ISC) || defined (sgi) || (defined (ardent) && defined (titan)))
 338 #  define KERNEL_FILE "/unix"
 339 # endif
 340
 341
 342 # if !defined (LDAV_SYMBOL) && defined (alliant)
 343 #  define LDAV_SYMBOL "_Loadavg"
 344 # endif
 345
 346 # if !defined(LDAV_SYMBOL) && ((defined(hpux) && !defined(hp9000s300)) || defined(_SEQUENT_) || defined(SVR4) || defined(ISC) || defined(sgi) || (defined (ardent) && defined (titan)) || defined (_AIX))
 347 #  define LDAV_SYMBOL "avenrun"
 348 # endif
 349
 350 # ifdef HAVE_UNISTD_H
 351 #  include <unistd.h>
 352 # endif
 353
 354 # include <stdio.h>
 355
 356 /* LOAD_AVE_TYPE should only get defined if we're going to use the
 357    nlist method.  */
 358 # if !defined(LOAD_AVE_TYPE) && (defined(BSD) || defined(LDAV_CVT) || defined(KERNEL_FILE) || defined(LDAV_SYMBOL))
 359 #  define LOAD_AVE_TYPE double
 360 # endif
 361
 362 # ifdef LOAD_AVE_TYPE
 363
 364 #  ifndef VMS
 365 #   ifndef __linux__
 366 #    ifdef HAVE_NLIST_H
 367 #     include <nlist.h>
 368 #    else
 369 #     include <a.out.h>
 370 #    endif
 371
 372 #    ifdef SUNOS_5
 373 #     include <fcntl.h>
 374 #     include <kvm.h>
 375 #     include <kstat.h>
 376 #    endif
 377
 378 #    if defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
 379 #     include <sys/pstat.h>
 380 #    endif
 381
 382 #    ifndef KERNEL_FILE
 383 #     define KERNEL_FILE "/vmunix"
 384 #    endif /* KERNEL_FILE */
 385
 386 #    ifndef LDAV_SYMBOL
 387 #     define LDAV_SYMBOL "_avenrun"
 388 #    endif /* LDAV_SYMBOL */
 389 #   endif /* __linux__ */
 390
 391 #  else /* VMS */
 392
 393 #   ifndef eunice
 394 #    include <iodef.h>
 395 #    include <descrip.h>
 396 #   else /* eunice */
 397 #    include <vms/iodef.h>
 398 #   endif /* eunice */
 399 #  endif /* VMS */
 400
 401 #  ifndef LDAV_CVT
 402 #   define LDAV_CVT(n) ((double) (n))
 403 #  endif /* !LDAV_CVT */
 404
 405 # endif /* LOAD_AVE_TYPE */
 406
 407 # if defined(__GNU__) && !defined (NeXT)
 408 /* Note that NeXT Openstep defines __GNU__ even though it should not.  */
 409 /* GNU system acts much like NeXT, for load average purposes,
 410    but not exactly.  */
 411 #  define NeXT
 412 #  define host_self mach_host_self
 413 # endif
 414
 415 # ifdef NeXT
 416 #  ifdef HAVE_MACH_MACH_H
 417 #   include <mach/mach.h>
 418 #  else
 419 #   include <mach.h>
 420 #  endif
 421 # endif /* NeXT */
 422
 423 # ifdef sgi
 424 #  include <sys/sysmp.h>
 425 # endif /* sgi */
 426
 427 # ifdef UMAX
 428 #  include <stdio.h>
 429 #  include <signal.h>
 430 #  include <sys/time.h>
 431 #  include <sys/wait.h>
 432 #  include <sys/syscall.h>
 433
 434 #  ifdef UMAX_43
 435 #   include <machine/cpu.h>
 436 #   include <inq_stats/statistics.h>
 437 #   include <inq_stats/sysstats.h>
 438 #   include <inq_stats/cpustats.h>
 439 #   include <inq_stats/procstats.h>
 440 #  else /* Not UMAX_43.  */
 441 #   include <sys/sysdefs.h>
 442 #   include <sys/statistics.h>
 443 #   include <sys/sysstats.h>
 444 #   include <sys/cpudefs.h>
 445 #   include <sys/cpustats.h>
 446 #   include <sys/procstats.h>
 447 #  endif /* Not UMAX_43.  */
 448 # endif /* UMAX */
 449
 450 # ifdef DGUX
 451 #  include <sys/dg_sys_info.h>
 452 # endif
 453
 454 # if defined(HAVE_FCNTL_H) || defined(_POSIX_VERSION)
 455 #  include <fcntl.h>
 456 # else
 457 #  include <sys/file.h>
 458 # endif
 459 \f
 460
 461 /* Avoid static vars inside a function since in HPUX they dump as pure.  */
 462
 463 # ifdef NeXT
 464 static processor_set_t default_set;
 465 static int getloadavg_initialized;
 466 # endif /* NeXT */
 467
 468 # ifdef UMAX
 469 static unsigned int cpus = 0;
 470 static unsigned int samples;
 471 # endif /* UMAX */
 472
 473 # ifdef DGUX
 474 static struct dg_sys_info_load_info load_info;  /* what-a-mouthful! */
 475 # endif /* DGUX */
 476
 477 #if !defined(HAVE_LIBKSTAT) && defined(LOAD_AVE_TYPE)
 478 /* File descriptor open to /dev/kmem or VMS load ave driver.  */
 479 static int channel;
 480 /* Nonzero iff channel is valid.  */
 481 static int getloadavg_initialized;
 482 /* Offset in kmem to seek to read load average, or 0 means invalid.  */
 483 static long offset;
 484
 485 #if !defined(VMS) && !defined(sgi) && !defined(__linux__)
 486 static struct nlist nl[2];
 487 #endif /* Not VMS or sgi */
 488
 489 #ifdef SUNOS_5
 490 static kvm_t *kd;
 491 #endif /* SUNOS_5 */
 492
 493 #endif /* LOAD_AVE_TYPE && !HAVE_LIBKSTAT */
 494 \f
 495 /* Put the 1 minute, 5 minute and 15 minute load averages
 496    into the first NELEM elements of LOADAVG.
 497    Return the number written (never more than 3, but may be less than NELEM),
 498    or -1 if an error occurred.  */
 499
 500 int
 501 getloadavg (loadavg, nelem)
 502      double loadavg[];
 503      int nelem;
 504 {
 505   int elem = 0;                 /* Return value.  */
 506
 507 # ifdef NO_GET_LOAD_AVG
 508 #  define LDAV_DONE
 509   /* Set errno to zero to indicate that there was no particular error;
 510      this function just can't work at all on this system.  */
 511   errno = 0;
 512   elem = -1;
 513 # endif
 514
 515 # if !defined (LDAV_DONE) && defined (HAVE_LIBKSTAT)
 516 /* Use libkstat because we don't have to be root.  */
 517 #  define LDAV_DONE
 518   kstat_ctl_t *kc;
 519   kstat_t *ksp;
 520   kstat_named_t *kn;
 521
 522   kc = kstat_open ();
 523   if (kc == 0)
 524     return -1;
 525   ksp = kstat_lookup (kc, "unix", 0, "system_misc");
 526   if (ksp == 0 )
 527     return -1;
 528   if (kstat_read (kc, ksp, 0) == -1)
 529     return -1;
 530
 531
 532   kn = kstat_data_lookup (ksp, "avenrun_1min");
 533   if (kn == 0)
 534     {
 535       /* Return -1 if no load average information is available.  */
 536       nelem = 0;
 537       elem = -1;
 538     }
 539
 540   if (nelem >= 1)
 541     loadavg[elem++] = (double) kn->value.ul/FSCALE;
 542
 543   if (nelem >= 2)
 544     {
 545       kn = kstat_data_lookup (ksp, "avenrun_5min");
 546       if (kn != 0)
 547         {
 548           loadavg[elem++] = (double) kn->value.ul/FSCALE;
 549
 550           if (nelem >= 3)
 551             {
 552               kn = kstat_data_lookup (ksp, "avenrun_15min");
 553               if (kn != 0)
 554                 loadavg[elem++] = (double) kn->value.ul/FSCALE;
 555             }
 556         }
 557     }
 558
 559   kstat_close (kc);
 560 # endif /* HAVE_LIBKSTAT */
 561
 562 # if !defined (LDAV_DONE) && defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
 563 /* Use pstat_getdynamic() because we don't have to be root.  */
 564 #  define LDAV_DONE
 565 #  undef LOAD_AVE_TYPE
 566
 567   struct pst_dynamic dyn_info;
 568   if (pstat_getdynamic (&dyn_info, sizeof (dyn_info), 0, 0) < 0)
 569     return -1;
 570   if (nelem > 0)
 571     loadavg[elem++] = dyn_info.psd_avg_1_min;
 572   if (nelem > 1)
 573     loadavg[elem++] = dyn_info.psd_avg_5_min;
 574   if (nelem > 2)
 575     loadavg[elem++] = dyn_info.psd_avg_15_min;
 576
 577 # endif /* hpux && HAVE_PSTAT_GETDYNAMIC */
 578
 579 # if !defined (LDAV_DONE) && defined (__linux__)
 580 #  define LDAV_DONE
 581 #  undef LOAD_AVE_TYPE
 582
 583 #  ifndef LINUX_LDAV_FILE
 584 #   define LINUX_LDAV_FILE "/proc/loadavg"
 585 #  endif
 586
 587   char ldavgbuf[40];
 588   double load_ave[3];
 589   int fd, count;
 590
 591   fd = open (LINUX_LDAV_FILE, O_RDONLY);
 592   if (fd == -1)
 593     return -1;
 594   count = read (fd, ldavgbuf, 40);
 595   (void) close (fd);
 596   if (count <= 0)
 597     return -1;
 598
 599   /* The following sscanf must use the C locale.  */
 600   setlocale (LC_NUMERIC, "C");
 601   count = sscanf (ldavgbuf, "%lf %lf %lf",
 602                   &load_ave[0], &load_ave[1], &load_ave[2]);
 603   setlocale (LC_NUMERIC, "");
 604   if (count < 1)
 605     return -1;
 606
 607   for (elem = 0; elem < nelem && elem < count; elem++)
 608     loadavg[elem] = load_ave[elem];
 609
 610   return elem;
 611
 612 # endif /* __linux__ */
 613
 614 # if !defined (LDAV_DONE) && defined (__NetBSD__)
 615 #  define LDAV_DONE
 616 #  undef LOAD_AVE_TYPE
 617
 618 #  ifndef NETBSD_LDAV_FILE
 619 #   define NETBSD_LDAV_FILE "/kern/loadavg"
 620 #  endif
 621
 622   unsigned long int load_ave[3], scale;
 623   int count;
 624   FILE *fp;
 625
 626   fp = fopen (NETBSD_LDAV_FILE, "r");
 627   if (fp == NULL)
 628     return -1;
 629   count = fscanf (fp, "%lu %lu %lu %lu\n",
 630                   &load_ave[0], &load_ave[1], &load_ave[2],
 631                   &scale);
 632   (void) fclose (fp);
 633   if (count != 4)
 634     return -1;
 635
 636   for (elem = 0; elem < nelem; elem++)
 637     loadavg[elem] = (double) load_ave[elem] / (double) scale;
 638
 639   return elem;
 640
 641 # endif /* __NetBSD__ */
 642
 643 # if !defined (LDAV_DONE) && defined (NeXT)
 644 #  define LDAV_DONE
 645   /* The NeXT code was adapted from iscreen 3.2.  */
 646
 647   host_t host;
 648   struct processor_set_basic_info info;
 649   unsigned info_count;
 650
 651   /* We only know how to get the 1-minute average for this system,
 652      so even if the caller asks for more than 1, we only return 1.  */
 653
 654   if (!getloadavg_initialized)
 655     {
 656       if (processor_set_default (host_self (), &default_set) == KERN_SUCCESS)
 657         getloadavg_initialized = 1;
 658     }
 659
 660   if (getloadavg_initialized)
 661     {
 662       info_count = PROCESSOR_SET_BASIC_INFO_COUNT;
 663       if (processor_set_info (default_set, PROCESSOR_SET_BASIC_INFO, &host,
 664                               (processor_set_info_t) &info, &info_count)
 665           != KERN_SUCCESS)
 666         getloadavg_initialized = 0;
 667       else
 668         {
 669           if (nelem > 0)
 670             loadavg[elem++] = (double) info.load_average / LOAD_SCALE;
 671         }
 672     }
 673
 674   if (!getloadavg_initialized)
 675     return -1;
 676 # endif /* NeXT */
 677
 678 # if !defined (LDAV_DONE) && defined (UMAX)
 679 #  define LDAV_DONE
 680 /* UMAX 4.2, which runs on the Encore Multimax multiprocessor, does not
 681    have a /dev/kmem.  Information about the workings of the running kernel
 682    can be gathered with inq_stats system calls.
 683    We only know how to get the 1-minute average for this system.  */
 684
 685   struct proc_summary proc_sum_data;
 686   struct stat_descr proc_info;
 687   double load;
 688   register unsigned int i, j;
 689
 690   if (cpus == 0)
 691     {
 692       register unsigned int c, i;
 693       struct cpu_config conf;
 694       struct stat_descr desc;
 695
 696       desc.sd_next = 0;
 697       desc.sd_subsys = SUBSYS_CPU;
 698       desc.sd_type = CPUTYPE_CONFIG;
 699       desc.sd_addr = (char *) &conf;
 700       desc.sd_size = sizeof conf;
 701
 702       if (inq_stats (1, &desc))
 703         return -1;
 704
 705       c = 0;
 706       for (i = 0; i < conf.config_maxclass; ++i)
 707         {
 708           struct class_stats stats;
 709           bzero ((char *) &stats, sizeof stats);
 710
 711           desc.sd_type = CPUTYPE_CLASS;
 712           desc.sd_objid = i;
 713           desc.sd_addr = (char *) &stats;
 714           desc.sd_size = sizeof stats;
 715
 716           if (inq_stats (1, &desc))
 717             return -1;
 718
 719           c += stats.class_numcpus;
 720         }
 721       cpus = c;
 722       samples = cpus < 2 ? 3 : (2 * cpus / 3);
 723     }
 724
 725   proc_info.sd_next = 0;
 726   proc_info.sd_subsys = SUBSYS_PROC;
 727   proc_info.sd_type = PROCTYPE_SUMMARY;
 728   proc_info.sd_addr = (char *) &proc_sum_data;
 729   proc_info.sd_size = sizeof (struct proc_summary);
 730   proc_info.sd_sizeused = 0;
 731
 732   if (inq_stats (1, &proc_info) != 0)
 733     return -1;
 734
 735   load = proc_sum_data.ps_nrunnable;
 736   j = 0;
 737   for (i = samples - 1; i > 0; --i)
 738     {
 739       load += proc_sum_data.ps_nrun[j];
 740       if (j++ == PS_NRUNSIZE)
 741         j = 0;
 742     }
 743
 744   if (nelem > 0)
 745     loadavg[elem++] = load / samples / cpus;
 746 # endif /* UMAX */
 747
 748 # if !defined (LDAV_DONE) && defined (DGUX)
 749 #  define LDAV_DONE
 750   /* This call can return -1 for an error, but with good args
 751      it's not supposed to fail.  The first argument is for no
 752      apparent reason of type `long int *'.  */
 753   dg_sys_info ((long int *) &load_info,
 754                DG_SYS_INFO_LOAD_INFO_TYPE,
 755                DG_SYS_INFO_LOAD_VERSION_0);
 756
 757   if (nelem > 0)
 758     loadavg[elem++] = load_info.one_minute;
 759   if (nelem > 1)
 760     loadavg[elem++] = load_info.five_minute;
 761   if (nelem > 2)
 762     loadavg[elem++] = load_info.fifteen_minute;
 763 # endif /* DGUX */
 764
 765 # if !defined (LDAV_DONE) && defined (apollo)
 766 #  define LDAV_DONE
 767 /* Apollo code from lisch@mentorg.com (Ray Lischner).
 768
 769    This system call is not documented.  The load average is obtained as
 770    three long integers, for the load average over the past minute,
 771    five minutes, and fifteen minutes.  Each value is a scaled integer,
 772    with 16 bits of integer part and 16 bits of fraction part.
 773
 774    I'm not sure which operating system first supported this system call,
 775    but I know that SR10.2 supports it.  */
 776
 777   extern void proc1_$get_loadav ();
 778   unsigned long load_ave[3];
 779
 780   proc1_$get_loadav (load_ave);
 781
 782   if (nelem > 0)
 783     loadavg[elem++] = load_ave[0] / 65536.0;
 784   if (nelem > 1)
 785     loadavg[elem++] = load_ave[1] / 65536.0;
 786   if (nelem > 2)
 787     loadavg[elem++] = load_ave[2] / 65536.0;
 788 # endif /* apollo */
 789
 790 # if !defined (LDAV_DONE) && defined (OSF_MIPS)
 791 #  define LDAV_DONE
 792
 793   struct tbl_loadavg load_ave;
 794   table (TBL_LOADAVG, 0, &load_ave, 1, sizeof (load_ave));
 795   loadavg[elem++]
 796     = (load_ave.tl_lscale == 0
 797        ? load_ave.tl_avenrun.d[0]
 798        : (load_ave.tl_avenrun.l[0] / (double) load_ave.tl_lscale));
 799 # endif /* OSF_MIPS */
 800
 801 # if !defined (LDAV_DONE) && (defined (__MSDOS__) || defined (WINDOWS32))
 802 #  define LDAV_DONE
 803
 804   /* A faithful emulation is going to have to be saved for a rainy day.  */
 805   for ( ; elem < nelem; elem++)
 806     {
 807       loadavg[elem] = 0.0;
 808     }
 809 # endif  /* __MSDOS__ || WINDOWS32 */
 810
 811 # if !defined (LDAV_DONE) && defined (OSF_ALPHA)
 812 #  define LDAV_DONE
 813
 814   struct tbl_loadavg load_ave;
 815   table (TBL_LOADAVG, 0, &load_ave, 1, sizeof (load_ave));
 816   for (elem = 0; elem < nelem; elem++)
 817     loadavg[elem]
 818       = (load_ave.tl_lscale == 0
 819        ? load_ave.tl_avenrun.d[elem]
 820        : (load_ave.tl_avenrun.l[elem] / (double) load_ave.tl_lscale));
 821 # endif /* OSF_ALPHA */
 822
 823 # if !defined (LDAV_DONE) && defined (VMS)
 824   /* VMS specific code -- read from the Load Ave driver.  */
 825
 826   LOAD_AVE_TYPE load_ave[3];
 827   static int getloadavg_initialized = 0;
 828 #  ifdef eunice
 829   struct
 830   {
 831     int dsc$w_length;
 832     char *dsc$a_pointer;
 833   } descriptor;
 834 #  endif
 835
 836   /* Ensure that there is a channel open to the load ave device.  */
 837   if (!getloadavg_initialized)
 838     {
 839       /* Attempt to open the channel.  */
 840 #  ifdef eunice
 841       descriptor.dsc$w_length = 18;
 842       descriptor.dsc$a_pointer = "$$VMS_LOAD_AVERAGE";
 843 #  else
 844       $DESCRIPTOR (descriptor, "LAV0:");
 845 #  endif
 846       if (sys$assign (&descriptor, &channel, 0, 0) & 1)
 847         getloadavg_initialized = 1;
 848     }
 849
 850   /* Read the load average vector.  */
 851   if (getloadavg_initialized
 852       && !(sys$qiow (0, channel, IO$_READVBLK, 0, 0, 0,
 853                      load_ave, 12, 0, 0, 0, 0) & 1))
 854     {
 855       sys$dassgn (channel);
 856       getloadavg_initialized = 0;
 857     }
 858
 859   if (!getloadavg_initialized)
 860     return -1;
 861 # endif /* VMS */
 862
 863 # if !defined (LDAV_DONE) && defined(LOAD_AVE_TYPE) && !defined(VMS)
 864
 865   /* UNIX-specific code -- read the average from /dev/kmem.  */
 866
 867 #  define LDAV_PRIVILEGED               /* This code requires special installation.  */
 868
 869   LOAD_AVE_TYPE load_ave[3];
 870
 871   /* Get the address of LDAV_SYMBOL.  */
 872   if (offset == 0)
 873     {
 874 #  ifndef sgi
 875 #   ifndef NLIST_STRUCT
 876       strcpy (nl[0].n_name, LDAV_SYMBOL);
 877       strcpy (nl[1].n_name, "");
 878 #   else /* NLIST_STRUCT */
 879 #    ifdef HAVE_STRUCT_NLIST_N_UN_N_NAME
 880       nl[0].n_un.n_name = LDAV_SYMBOL;
 881       nl[1].n_un.n_name = 0;
 882 #    else /* not HAVE_STRUCT_NLIST_N_UN_N_NAME */
 883       nl[0].n_name = LDAV_SYMBOL;
 884       nl[1].n_name = 0;
 885 #    endif /* not HAVE_STRUCT_NLIST_N_UN_N_NAME */
 886 #   endif /* NLIST_STRUCT */
 887
 888 #   ifndef SUNOS_5
 889       if (
 890 #    if !(defined (_AIX) && !defined (ps2))
 891           nlist (KERNEL_FILE, nl)
 892 #    else  /* _AIX */
 893           knlist (nl, 1, sizeof (nl[0]))
 894 #    endif
 895           >= 0)
 896           /* Omit "&& nl[0].n_type != 0 " -- it breaks on Sun386i.  */
 897           {
 898 #    ifdef FIXUP_KERNEL_SYMBOL_ADDR
 899             FIXUP_KERNEL_SYMBOL_ADDR (nl);
 900 #    endif
 901             offset = nl[0].n_value;
 902           }
 903 #   endif /* !SUNOS_5 */
 904 #  else  /* sgi */
 905       int ldav_off;
 906
 907       ldav_off = sysmp (MP_KERNADDR, MPKA_AVENRUN);
 908       if (ldav_off != -1)
 909         offset = (long) ldav_off & 0x7fffffff;
 910 #  endif /* sgi */
 911     }
 912
 913   /* Make sure we have /dev/kmem open.  */
 914   if (!getloadavg_initialized)
 915     {
 916 #  ifndef SUNOS_5
 917       channel = open ("/dev/kmem", 0);
 918       if (channel >= 0)
 919         {
 920           /* Set the channel to close on exec, so it does not
 921              litter any child's descriptor table.  */
 922 #   ifdef F_SETFD
 923 #    ifndef FD_CLOEXEC
 924 #     define FD_CLOEXEC 1
 925 #    endif
 926           (void) fcntl (channel, F_SETFD, FD_CLOEXEC);
 927 #   endif
 928           getloadavg_initialized = 1;
 929         }
 930 #  else /* SUNOS_5 */
 931       /* We pass 0 for the kernel, corefile, and swapfile names
 932          to use the currently running kernel.  */
 933       kd = kvm_open (0, 0, 0, O_RDONLY, 0);
 934       if (kd != 0)
 935         {
 936           /* nlist the currently running kernel.  */
 937           kvm_nlist (kd, nl);
 938           offset = nl[0].n_value;
 939           getloadavg_initialized = 1;
 940         }
 941 #  endif /* SUNOS_5 */
 942     }
 943
 944   /* If we can, get the load average values.  */
 945   if (offset && getloadavg_initialized)
 946     {
 947       /* Try to read the load.  */
 948 #  ifndef SUNOS_5
 949       if (lseek (channel, offset, 0) == -1L
 950           || read (channel, (char *) load_ave, sizeof (load_ave))
 951           != sizeof (load_ave))
 952         {
 953           close (channel);
 954           getloadavg_initialized = 0;
 955         }
 956 #  else  /* SUNOS_5 */
 957       if (kvm_read (kd, offset, (char *) load_ave, sizeof (load_ave))
 958           != sizeof (load_ave))
 959         {
 960           kvm_close (kd);
 961           getloadavg_initialized = 0;
 962         }
 963 #  endif /* SUNOS_5 */
 964     }
 965
 966   if (offset == 0 || !getloadavg_initialized)
 967     return -1;
 968 # endif /* LOAD_AVE_TYPE and not VMS */
 969
 970 # if !defined (LDAV_DONE) && defined (LOAD_AVE_TYPE) /* Including VMS.  */
 971   if (nelem > 0)
 972     loadavg[elem++] = LDAV_CVT (load_ave[0]);
 973   if (nelem > 1)
 974     loadavg[elem++] = LDAV_CVT (load_ave[1]);
 975   if (nelem > 2)
 976     loadavg[elem++] = LDAV_CVT (load_ave[2]);
 977
 978 #  define LDAV_DONE
 979 # endif /* !LDAV_DONE && LOAD_AVE_TYPE */
 980
 981 # ifdef LDAV_DONE
 982   return elem;
 983 # else
 984   /* Set errno to zero to indicate that there was no particular error;
 985      this function just can't work at all on this system.  */
 986   errno = 0;
 987   return -1;
 988 # endif
 989 }
 990
 991 #endif /* ! HAVE_GETLOADAVG */
 992 \f
 993 #ifdef TEST
 994 #include "make.h"
 995
 996 int
 997 main (argc, argv)
 998      int argc;
 999      char **argv;
1000 {
1001   int naptime = 0;
1002
1003   if (argc > 1)
1004     naptime = atoi (argv[1]);
1005
1006   while (1)
1007     {
1008       double avg[3];
1009       int loads;
1010
1011       errno = 0;                /* Don't be misled if it doesn't set errno.  */
1012       loads = getloadavg (avg, 3);
1013       if (loads == -1)
1014         {
1015           perror ("Error getting load average");
1016           exit (1);
1017         }
1018       if (loads > 0)
1019         printf ("1-minute: %f  ", avg[0]);
1020       if (loads > 1)
1021         printf ("5-minute: %f  ", avg[1]);
1022       if (loads > 2)
1023         printf ("15-minute: %f  ", avg[2]);
1024       if (loads > 0)
1025         putchar ('\n');
1026
1027       if (naptime == 0)
1028         break;
1029       sleep (naptime);
1030     }
1031
1032   exit (0);
1033 }
1034 #endif /* TEST */