1 /* Get the system load averages.
2
3 Copyright (C) 1985-1989, 1991-1995, 1997, 1999-2000, 2003-2022 Free Software
4 Foundation, Inc.
5
6 NOTE: The canonical source of this file is maintained with gnulib.
7 Bugs can be reported to bug-gnulib@gnu.org.
8
9 This program is free software: you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation, either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <https://www.gnu.org/licenses/>. */
21
22 /* Compile-time symbols that this file uses:
23
24 HAVE_PSTAT_GETDYNAMIC Define this if your system has the
25 pstat_getdynamic function. I think it
26 is unique to HPUX9. The best way to get the
27 definition is through the AC_FUNC_GETLOADAVG
28 macro that comes with autoconf 2.13 or newer.
29 If that isn't an option, then just put
30 AC_CHECK_FUNCS(pstat_getdynamic) in your
31 configure.ac file.
32 HAVE_LIBPERFSTAT Define this if your system has the
33 perfstat_cpu_total function in libperfstat (AIX).
34 FIXUP_KERNEL_SYMBOL_ADDR() Adjust address in returned struct nlist.
35 KERNEL_FILE Name of the kernel file to nlist.
36 LDAV_CVT() Scale the load average from the kernel.
37 Returns a double.
38 LDAV_SYMBOL Name of kernel symbol giving load average.
39 LOAD_AVE_TYPE Type of the load average array in the kernel.
40 Must be defined unless one of
41 apollo, DGUX, NeXT, or UMAX is defined;
42 or we have libkstat;
43 otherwise, no load average is available.
44 HAVE_NLIST_H nlist.h is available. NLIST_STRUCT defaults
45 to this.
46 NLIST_STRUCT Include nlist.h, not a.out.h.
47 N_NAME_POINTER The nlist n_name element is a pointer,
48 not an array.
49 HAVE_STRUCT_NLIST_N_UN_N_NAME 'n_un.n_name' is member of 'struct nlist'.
50 LINUX_LDAV_FILE [__linux__, __ANDROID__, __CYGWIN__]: File
51 containing load averages.
52
53 Specific system predefines this file uses, aside from setting
54 default values if not emacs:
55
56 apollo
57 BSD Real BSD, not just BSD-like.
58 DGUX
59 eunice UNIX emulator under VMS.
60 hpux
61 __MSDOS__ No-op for MSDOS.
62 NeXT
63 sgi
64 UMAX
65 UMAX4_3
66 VMS
67 _WIN32 Native Windows (possibly also defined on Cygwin)
68 __linux__, __ANDROID__ Linux: assumes /proc file system mounted.
69 Support from Michael K. Johnson.
70 __CYGWIN__ Cygwin emulates linux /proc/loadavg.
71 __NetBSD__ NetBSD: assumes /kern file system mounted.
72
73 In addition, to avoid nesting many #ifdefs, we internally set
74 LDAV_DONE to indicate that the load average has been computed.
75
76 We also #define LDAV_PRIVILEGED if a program will require
77 special installation to be able to call getloadavg. */
78
79 #include <config.h>
80
81 /* Specification. */
82 #include <stdlib.h>
83
84 #include <errno.h>
85 #include <stdbool.h>
86 #include <stdio.h>
87
88 # include <sys/types.h>
89
90 # if HAVE_SYS_PARAM_H
91 # include <sys/param.h>
92 # endif
93
94 # include "intprops.h"
95
96 # if defined _WIN32 && ! defined __CYGWIN__ && ! defined WINDOWS32
97 # define WINDOWS32
98 # endif
99
100 # ifdef NeXT
101 /* NeXT in the 2.{0,1,2} releases defines BSD in <sys/param.h>, which
102 conflicts with the definition understood in this file, that this
103 really is BSD. */
104 # undef BSD
105
106 /* NeXT defines FSCALE in <sys/param.h>. However, we take FSCALE being
107 defined to mean that the nlist method should be used, which is not true. */
108 # undef FSCALE
109 # endif
110
111 /* Same issues as for NeXT apply to the HURD-based GNU system. */
112 # ifdef __GNU__
113 # undef BSD
114 # undef FSCALE
115 # endif /* __GNU__ */
116
117 /* Set values that are different from the defaults, which are
118 set a little farther down with #ifndef. */
119
120
121 /* Some shorthands. */
122
123 # if defined (HPUX) && !defined (hpux)
124 # define hpux
125 # endif
126
127 # if defined (__hpux) && !defined (hpux)
128 # define hpux
129 # endif
130
131 # if defined (__sun) && !defined (sun)
132 # define sun
133 # endif
134
135 # if defined (hp300) && !defined (hpux)
136 # define MORE_BSD
137 # endif
138
139 # if defined (__SVR4) && !defined (SVR4)
140 # define SVR4
141 # endif
142
143 # if (defined (sun) && defined (SVR4)) || defined (SOLARIS2)
144 # define SUNOS_5
145 # endif
146
147 # if defined (__osf__) && (defined (__alpha) || defined (__alpha__))
148 # define OSF_ALPHA
149 # include <sys/mbuf.h>
150 # include <sys/socket.h>
151 # include <net/route.h>
152 # include <sys/table.h>
153 /* Tru64 4.0D's table.h redefines sys */
154 # undef sys
155 # endif
156
157 # if defined (__osf__) && (defined (mips) || defined (__mips__))
158 # define OSF_MIPS
159 # include <sys/table.h>
160 # endif
161
162
163 /* VAX C can't handle multi-line #ifs, or lines longer than 256 chars. */
164 # ifndef LOAD_AVE_TYPE
165
166 # ifdef MORE_BSD
167 # define LOAD_AVE_TYPE long
168 # endif
169
170 # ifdef sun
171 # define LOAD_AVE_TYPE long
172 # endif
173
174 # ifdef sgi
175 # define LOAD_AVE_TYPE long
176 # endif
177
178 # ifdef SVR4
179 # define LOAD_AVE_TYPE long
180 # endif
181
182 # ifdef OSF_ALPHA
183 # define LOAD_AVE_TYPE long
184 # endif
185
186 # if defined _AIX && ! defined HAVE_LIBPERFSTAT
187 # define LOAD_AVE_TYPE long
188 # endif
189
190 # endif /* No LOAD_AVE_TYPE. */
191
192 # ifdef OSF_ALPHA
193 /* <sys/param.h> defines an incorrect value for FSCALE on Alpha OSF/1,
194 according to ghazi@noc.rutgers.edu. */
195 # undef FSCALE
196 # define FSCALE 1024.0
197 # endif
198
199
200 # ifndef FSCALE
201
202 /* SunOS and some others define FSCALE in sys/param.h. */
203
204 # ifdef MORE_BSD
205 # define FSCALE 2048.0
206 # endif
207
208 # if defined (MIPS) || defined (SVR4)
209 # define FSCALE 256
210 # endif
211
212 # if defined (sgi)
213 /* Sometimes both MIPS and sgi are defined, so FSCALE was just defined
214 above under #ifdef MIPS. But we want the sgi value. */
215 # undef FSCALE
216 # define FSCALE 1000.0
217 # endif
218
219 # if defined _AIX && !defined HAVE_LIBPERFSTAT
220 # define FSCALE 65536.0
221 # endif
222
223 # endif /* Not FSCALE. */
224
225 # if !defined (LDAV_CVT) && defined (FSCALE)
226 # define LDAV_CVT(n) (((double) (n)) / FSCALE)
227 # endif
228
229 # ifndef NLIST_STRUCT
230 # if HAVE_NLIST_H
231 # define NLIST_STRUCT
232 # endif
233 # endif
234
235 # if defined (sgi) || (defined (mips) && !defined (BSD))
236 # define FIXUP_KERNEL_SYMBOL_ADDR(nl) ((nl)[0].n_value &= ~(1 << 31))
237 # endif
238
239
240 # if !defined (KERNEL_FILE) && defined (hpux)
241 # define KERNEL_FILE "/hp-ux"
242 # endif
243
244 # if !defined (KERNEL_FILE) && (defined (MIPS) || defined (SVR4) || defined (ISC) || defined (sgi))
245 # define KERNEL_FILE "/unix"
246 # endif
247
248
249 # if !defined (LDAV_SYMBOL) && (defined (hpux) || defined (SVR4) || defined (ISC) || defined (sgi) || (defined (_AIX) && !defined(HAVE_LIBPERFSTAT)))
250 # define LDAV_SYMBOL "avenrun"
251 # endif
252
253 # ifdef HAVE_UNISTD_H
254 # include <unistd.h>
255 # endif
256
257 /* LOAD_AVE_TYPE should only get defined if we're going to use the
258 nlist method. */
259 # if !defined (LOAD_AVE_TYPE) && (defined (BSD) || defined (LDAV_CVT) || defined (KERNEL_FILE) || defined (LDAV_SYMBOL))
260 # define LOAD_AVE_TYPE double
261 # endif
262
263 # ifdef LOAD_AVE_TYPE
264
265 # ifndef __VMS
266 # if !(defined __linux__ || defined __ANDROID__)
267 # ifndef NLIST_STRUCT
268 # include <a.out.h>
269 # else /* NLIST_STRUCT */
270 # include <nlist.h>
271 # endif /* NLIST_STRUCT */
272
273 # ifdef SUNOS_5
274 # include <kvm.h>
275 # include <kstat.h>
276 # endif
277
278 # if defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
279 # include <sys/pstat.h>
280 # endif
281
282 # ifndef KERNEL_FILE
283 # define KERNEL_FILE "/vmunix"
284 # endif /* KERNEL_FILE */
285
286 # ifndef LDAV_SYMBOL
287 # define LDAV_SYMBOL "_avenrun"
288 # endif /* LDAV_SYMBOL */
289 # endif /* __linux__ || __ANDROID__ */
290
291 # else /* __VMS */
292
293 # ifndef eunice
294 # include <iodef.h>
295 # include <descrip.h>
296 # else /* eunice */
297 # include <vms/iodef.h>
298 # endif /* eunice */
299 # endif /* __VMS */
300
301 # ifndef LDAV_CVT
302 # define LDAV_CVT(n) ((double) (n))
303 # endif /* !LDAV_CVT */
304
305 # endif /* LOAD_AVE_TYPE */
306
307 # if defined HAVE_LIBPERFSTAT
308 # include <sys/protosw.h>
309 # include <libperfstat.h>
310 # include <sys/proc.h>
311 # ifndef SBITS
312 # define SBITS 16
313 # endif
314 # endif
315
316 # if defined (__GNU__) && !defined (NeXT)
317 /* Note that NeXT Openstep defines __GNU__ even though it should not. */
318 /* GNU system acts much like NeXT, for load average purposes,
319 but not exactly. */
320 # define NeXT
321 # define host_self mach_host_self
322 # endif
323
324 # ifdef NeXT
325 # ifdef HAVE_MACH_MACH_H
326 # include <mach/mach.h>
327 # else
328 # include <mach.h>
329 # endif
330 # endif /* NeXT */
331
332 # ifdef sgi
333 # include <sys/sysmp.h>
334 # endif /* sgi */
335
336 # ifdef UMAX
337 # include <signal.h>
338 # include <sys/time.h>
339 # include <sys/wait.h>
340 # include <sys/syscall.h>
341
342 # ifdef UMAX_43
343 # include <machine/cpu.h>
344 # include <inq_stats/statistics.h>
345 # include <inq_stats/sysstats.h>
346 # include <inq_stats/cpustats.h>
347 # include <inq_stats/procstats.h>
348 # else /* Not UMAX_43. */
349 # include <sys/sysdefs.h>
350 # include <sys/statistics.h>
351 # include <sys/sysstats.h>
352 # include <sys/cpudefs.h>
353 # include <sys/cpustats.h>
354 # include <sys/procstats.h>
355 # endif /* Not UMAX_43. */
356 # endif /* UMAX */
357
358 # ifdef DGUX
359 # include <sys/dg_sys_info.h>
360 # endif
361
362 # if (defined __linux__ || defined __ANDROID__ \
363 || defined __CYGWIN__ || defined SUNOS_5 \
364 || (defined LOAD_AVE_TYPE && ! defined __VMS))
365 # include <fcntl.h>
366 # endif
367
368 /* Avoid static vars inside a function since in HPUX they dump as pure. */
369
370 # ifdef NeXT
371 static processor_set_t default_set;
372 static bool getloadavg_initialized;
373 # endif /* NeXT */
374
375 # ifdef UMAX
376 static unsigned int cpus = 0;
377 static unsigned int samples;
378 # endif /* UMAX */
379
380 # ifdef DGUX
381 static struct dg_sys_info_load_info load_info; /* what-a-mouthful! */
382 # endif /* DGUX */
383
384 # if !defined (HAVE_LIBKSTAT) && defined (LOAD_AVE_TYPE)
385 /* File descriptor open to /dev/kmem or VMS load ave driver. */
386 static int channel;
387 /* True if channel is valid. */
388 static bool getloadavg_initialized;
389 /* Offset in kmem to seek to read load average, or 0 means invalid. */
390 static long offset;
391
392 # if ! defined __VMS && ! defined sgi && ! (defined __linux__ || defined __ANDROID__)
393 static struct nlist name_list[2];
394 # endif
395
396 # ifdef SUNOS_5
397 static kvm_t *kd;
398 # endif /* SUNOS_5 */
399
400 # endif /* LOAD_AVE_TYPE && !HAVE_LIBKSTAT */
401
402 /* Put the 1 minute, 5 minute and 15 minute load averages
403 into the first NELEM elements of LOADAVG.
404 Return the number written (never more than 3, but may be less than NELEM),
405 or -1 (setting errno) if an error occurred. */
406
407 int
408 getloadavg (double loadavg[], int nelem)
409 {
410 int elem = 0; /* Return value. */
411
412 # ifdef NO_GET_LOAD_AVG
413 # define LDAV_DONE
414 errno = ENOSYS;
415 elem = -1;
416 # endif
417
418 # if !defined (LDAV_DONE) && defined (HAVE_LIBKSTAT) /* Solaris <= 2.6 */
419 /* Use libkstat because we don't have to be root. */
420 # define LDAV_DONE
421 kstat_ctl_t *kc;
422 kstat_t *ksp;
423 kstat_named_t *kn;
424 int saved_errno;
425
426 kc = kstat_open ();
427 if (kc == NULL)
428 return -1;
429 ksp = kstat_lookup (kc, "unix", 0, "system_misc");
430 if (ksp == NULL)
431 return -1;
432 if (kstat_read (kc, ksp, 0) == -1)
433 return -1;
434
435
436 kn = kstat_data_lookup (ksp, "avenrun_1min");
437 if (kn == NULL)
438 {
439 /* Return -1 if no load average information is available. */
440 nelem = 0;
441 elem = -1;
442 }
443
444 if (nelem >= 1)
445 loadavg[elem++] = (double) kn->value.ul / FSCALE;
446
447 if (nelem >= 2)
448 {
449 kn = kstat_data_lookup (ksp, "avenrun_5min");
450 if (kn != NULL)
451 {
452 loadavg[elem++] = (double) kn->value.ul / FSCALE;
453
454 if (nelem >= 3)
455 {
456 kn = kstat_data_lookup (ksp, "avenrun_15min");
457 if (kn != NULL)
458 loadavg[elem++] = (double) kn->value.ul / FSCALE;
459 }
460 }
461 }
462
463 saved_errno = errno;
464 kstat_close (kc);
465 errno = saved_errno;
466 # endif /* HAVE_LIBKSTAT */
467
468 # if !defined (LDAV_DONE) && defined (hpux) && defined (HAVE_PSTAT_GETDYNAMIC)
469 /* HP-UX */
470 /* Use pstat_getdynamic() because we don't have to be root. */
471 # define LDAV_DONE
472 # undef LOAD_AVE_TYPE
473
474 struct pst_dynamic dyn_info;
475 if (pstat_getdynamic (&dyn_info, sizeof (dyn_info), 0, 0) < 0)
476 return -1;
477 if (nelem > 0)
478 loadavg[elem++] = dyn_info.psd_avg_1_min;
479 if (nelem > 1)
480 loadavg[elem++] = dyn_info.psd_avg_5_min;
481 if (nelem > 2)
482 loadavg[elem++] = dyn_info.psd_avg_15_min;
483
484 # endif /* hpux && HAVE_PSTAT_GETDYNAMIC */
485
486 # if ! defined LDAV_DONE && defined HAVE_LIBPERFSTAT /* AIX */
487 # define LDAV_DONE
488 # undef LOAD_AVE_TYPE
489 /* Use perfstat_cpu_total because we don't have to be root. */
490 {
491 perfstat_cpu_total_t cpu_stats;
492 int result = perfstat_cpu_total (NULL, &cpu_stats, sizeof cpu_stats, 1);
493 if (result == -1)
494 return result;
495 loadavg[0] = cpu_stats.loadavg[0] / (double)(1 << SBITS);
496 loadavg[1] = cpu_stats.loadavg[1] / (double)(1 << SBITS);
497 loadavg[2] = cpu_stats.loadavg[2] / (double)(1 << SBITS);
498 elem = 3;
499 }
500 # endif
501
502 # if !defined (LDAV_DONE) && (defined __linux__ || defined __ANDROID__ || defined __CYGWIN__)
503 /* Linux without glibc, Android, Cygwin */
504 # define LDAV_DONE
505 # undef LOAD_AVE_TYPE
506
507 # ifndef LINUX_LDAV_FILE
508 # define LINUX_LDAV_FILE "/proc/loadavg"
509 # endif
510
511 char ldavgbuf[3 * (INT_STRLEN_BOUND (int) + sizeof ".00 ")];
512 char const *ptr = ldavgbuf;
513 int fd, count, saved_errno;
514
515 fd = open (LINUX_LDAV_FILE, O_RDONLY | O_CLOEXEC);
516 if (fd == -1)
517 return -1;
518 count = read (fd, ldavgbuf, sizeof ldavgbuf - 1);
519 saved_errno = errno;
520 (void) close (fd);
521 errno = saved_errno;
522 if (count <= 0)
523 return -1;
524 ldavgbuf[count] = '\0';
525
526 for (elem = 0; elem < nelem; elem++)
527 {
528 double numerator = 0;
529 double denominator = 1;
530
531 while (*ptr == ' ')
532 ptr++;
533
534 /* Finish if this number is missing, and report an error if all
535 were missing. */
536 if (! ('0' <= *ptr && *ptr <= '9'))
537 {
538 if (elem == 0)
539 {
540 errno = ENOTSUP;
541 return -1;
542 }
543 break;
544 }
545
546 while ('0' <= *ptr && *ptr <= '9')
547 numerator = 10 * numerator + (*ptr++ - '0');
548
549 if (*ptr == '.')
550 for (ptr++; '0' <= *ptr && *ptr <= '9'; ptr++)
551 numerator = 10 * numerator + (*ptr - '0'), denominator *= 10;
552
553 loadavg[elem] = numerator / denominator;
554 }
555
556 return elem;
557
558 # endif /* __linux__ || __ANDROID__ || __CYGWIN__ */
559
560 # if !defined (LDAV_DONE) && defined (__NetBSD__) /* NetBSD < 0.9 */
561 # define LDAV_DONE
562 # undef LOAD_AVE_TYPE
563
564 # ifndef NETBSD_LDAV_FILE
565 # define NETBSD_LDAV_FILE "/kern/loadavg"
566 # endif
567
568 unsigned long int load_ave[3], scale;
569 int count;
570 char readbuf[4 * INT_BUFSIZE_BOUND (unsigned long int) + 1];
571 int fd = open (NETBSD_LDAV_FILE, O_RDONLY | O_CLOEXEC);
572 if (fd < 0)
573 return fd;
574 int nread = read (fd, readbuf, sizeof readbuf - 1);
575 int err = errno;
576 close (fd);
577 if (nread < 0)
578 {
579 errno = err;
580 return -1;
581 }
582 readbuf[nread] = '\0';
583 count = sscanf (readbuf, "%lu %lu %lu %lu\n",
584 &load_ave[0], &load_ave[1], &load_ave[2],
585 &scale);
586 if (count != 4)
587 {
588 errno = ENOTSUP;
589 return -1;
590 }
591
592 for (elem = 0; elem < nelem; elem++)
593 loadavg[elem] = (double) load_ave[elem] / (double) scale;
594
595 return elem;
596
597 # endif /* __NetBSD__ */
598
599 # if !defined (LDAV_DONE) && defined (NeXT) /* NeXTStep */
600 # define LDAV_DONE
601 /* The NeXT code was adapted from iscreen 3.2. */
602
603 host_t host;
604 struct processor_set_basic_info info;
605 unsigned int info_count;
606
607 /* We only know how to get the 1-minute average for this system,
608 so even if the caller asks for more than 1, we only return 1. */
609
610 if (!getloadavg_initialized)
611 {
612 if (processor_set_default (host_self (), &default_set) == KERN_SUCCESS)
613 getloadavg_initialized = true;
614 }
615
616 if (getloadavg_initialized)
617 {
618 info_count = PROCESSOR_SET_BASIC_INFO_COUNT;
619 if (processor_set_info (default_set, PROCESSOR_SET_BASIC_INFO, &host,
620 (processor_set_info_t) &info, &info_count)
621 != KERN_SUCCESS)
622 getloadavg_initialized = false;
623 else
624 {
625 if (nelem > 0)
626 loadavg[elem++] = (double) info.load_average / LOAD_SCALE;
627 }
628 }
629
630 if (!getloadavg_initialized)
631 {
632 errno = ENOTSUP;
633 return -1;
634 }
635 # endif /* NeXT */
636
637 # if !defined (LDAV_DONE) && defined (UMAX)
638 # define LDAV_DONE
639 /* UMAX 4.2, which runs on the Encore Multimax multiprocessor, does not
640 have a /dev/kmem. Information about the workings of the running kernel
641 can be gathered with inq_stats system calls.
642 We only know how to get the 1-minute average for this system. */
643
644 struct proc_summary proc_sum_data;
645 struct stat_descr proc_info;
646 double load;
647 register unsigned int i, j;
648
649 if (cpus == 0)
650 {
651 register unsigned int c, i;
652 struct cpu_config conf;
653 struct stat_descr desc;
654
655 desc.sd_next = 0;
656 desc.sd_subsys = SUBSYS_CPU;
657 desc.sd_type = CPUTYPE_CONFIG;
658 desc.sd_addr = (char *) &conf;
659 desc.sd_size = sizeof conf;
660
661 if (inq_stats (1, &desc))
662 return -1;
663
664 c = 0;
665 for (i = 0; i < conf.config_maxclass; ++i)
666 {
667 struct class_stats stats;
668 memset (&stats, 0, sizeof stats);
669
670 desc.sd_type = CPUTYPE_CLASS;
671 desc.sd_objid = i;
672 desc.sd_addr = (char *) &stats;
673 desc.sd_size = sizeof stats;
674
675 if (inq_stats (1, &desc))
676 return -1;
677
678 c += stats.class_numcpus;
679 }
680 cpus = c;
681 samples = cpus < 2 ? 3 : (2 * cpus / 3);
682 }
683
684 proc_info.sd_next = 0;
685 proc_info.sd_subsys = SUBSYS_PROC;
686 proc_info.sd_type = PROCTYPE_SUMMARY;
687 proc_info.sd_addr = (char *) &proc_sum_data;
688 proc_info.sd_size = sizeof (struct proc_summary);
689 proc_info.sd_sizeused = 0;
690
691 if (inq_stats (1, &proc_info) != 0)
692 return -1;
693
694 load = proc_sum_data.ps_nrunnable;
695 j = 0;
696 for (i = samples - 1; i > 0; --i)
697 {
698 load += proc_sum_data.ps_nrun[j];
699 if (j++ == PS_NRUNSIZE)
700 j = 0;
701 }
702
703 if (nelem > 0)
704 loadavg[elem++] = load / samples / cpus;
705 # endif /* UMAX */
706
707 # if !defined (LDAV_DONE) && defined (DGUX)
708 # define LDAV_DONE
709 /* This call can return -1 for an error, but with good args
710 it's not supposed to fail. The first argument is for no
711 apparent reason of type 'long int *'. */
712 dg_sys_info ((long int *) &load_info,
713 DG_SYS_INFO_LOAD_INFO_TYPE,
714 DG_SYS_INFO_LOAD_VERSION_0);
715
716 if (nelem > 0)
717 loadavg[elem++] = load_info.one_minute;
718 if (nelem > 1)
719 loadavg[elem++] = load_info.five_minute;
720 if (nelem > 2)
721 loadavg[elem++] = load_info.fifteen_minute;
722 # endif /* DGUX */
723
724 # if !defined (LDAV_DONE) && defined (apollo)
725 # define LDAV_DONE
726 /* Apollo code from lisch@mentorg.com (Ray Lischner).
727
728 This system call is not documented. The load average is obtained as
729 three long integers, for the load average over the past minute,
730 five minutes, and fifteen minutes. Each value is a scaled integer,
731 with 16 bits of integer part and 16 bits of fraction part.
732
733 I'm not sure which operating system first supported this system call,
734 but I know that SR10.2 supports it. */
735
736 extern void proc1_$get_loadav ();
737 unsigned long load_ave[3];
738
739 proc1_$get_loadav (load_ave);
740
741 if (nelem > 0)
742 loadavg[elem++] = load_ave[0] / 65536.0;
743 if (nelem > 1)
744 loadavg[elem++] = load_ave[1] / 65536.0;
745 if (nelem > 2)
746 loadavg[elem++] = load_ave[2] / 65536.0;
747 # endif /* apollo */
748
749 # if !defined (LDAV_DONE) && defined (OSF_MIPS)
750 # define LDAV_DONE
751
752 struct tbl_loadavg load_ave;
753 table (TBL_LOADAVG, 0, &load_ave, 1, sizeof (load_ave));
754 loadavg[elem++]
755 = (load_ave.tl_lscale == 0
756 ? load_ave.tl_avenrun.d[0]
757 : (load_ave.tl_avenrun.l[0] / (double) load_ave.tl_lscale));
758 # endif /* OSF_MIPS */
759
760 # if !defined (LDAV_DONE) && (defined (__MSDOS__) || defined (WINDOWS32))
761 /* DJGPP */
762 # define LDAV_DONE
763
764 /* A faithful emulation is going to have to be saved for a rainy day. */
765 for ( ; elem < nelem; elem++)
766 {
767 loadavg[elem] = 0.0;
768 }
769 # endif /* __MSDOS__ || WINDOWS32 */
770
771 # if !defined (LDAV_DONE) && defined (OSF_ALPHA) /* OSF/1 */
772 # define LDAV_DONE
773
774 struct tbl_loadavg load_ave;
775 table (TBL_LOADAVG, 0, &load_ave, 1, sizeof (load_ave));
776 for (elem = 0; elem < nelem; elem++)
777 loadavg[elem]
778 = (load_ave.tl_lscale == 0
779 ? load_ave.tl_avenrun.d[elem]
780 : (load_ave.tl_avenrun.l[elem] / (double) load_ave.tl_lscale));
781 # endif /* OSF_ALPHA */
782
783 # if ! defined LDAV_DONE && defined __VMS /* VMS */
784 /* VMS specific code -- read from the Load Ave driver. */
785
786 LOAD_AVE_TYPE load_ave[3];
787 static bool getloadavg_initialized;
788 # ifdef eunice
789 struct
790 {
791 int dsc$w_length;
792 char *dsc$a_pointer;
793 } descriptor;
794 # endif
795
796 /* Ensure that there is a channel open to the load ave device. */
797 if (!getloadavg_initialized)
798 {
799 /* Attempt to open the channel. */
800 # ifdef eunice
801 descriptor.dsc$w_length = 18;
802 descriptor.dsc$a_pointer = "$$VMS_LOAD_AVERAGE";
803 # else
804 $DESCRIPTOR (descriptor, "LAV0:");
805 # endif
806 if (sys$assign (&descriptor, &channel, 0, 0) & 1)
807 getloadavg_initialized = true;
808 }
809
810 /* Read the load average vector. */
811 if (getloadavg_initialized
812 && !(sys$qiow (0, channel, IO$_READVBLK, 0, 0, 0,
813 load_ave, 12, 0, 0, 0, 0) & 1))
814 {
815 sys$dassgn (channel);
816 getloadavg_initialized = false;
817 }
818
819 if (!getloadavg_initialized)
820 {
821 errno = ENOTSUP;
822 return -1;
823 }
824 # endif /* ! defined LDAV_DONE && defined __VMS */
825
826 # if ! defined LDAV_DONE && defined LOAD_AVE_TYPE && ! defined __VMS
827 /* IRIX, other old systems */
828
829 /* UNIX-specific code -- read the average from /dev/kmem. */
830
831 # define LDAV_PRIVILEGED /* This code requires special installation. */
832
833 LOAD_AVE_TYPE load_ave[3];
834
835 /* Get the address of LDAV_SYMBOL. */
836 if (offset == 0)
837 {
838 # ifndef sgi
839 # if ! defined NLIST_STRUCT || ! defined N_NAME_POINTER
840 strcpy (name_list[0].n_name, LDAV_SYMBOL);
841 strcpy (name_list[1].n_name, "");
842 # else /* NLIST_STRUCT */
843 # ifdef HAVE_STRUCT_NLIST_N_UN_N_NAME
844 name_list[0].n_un.n_name = LDAV_SYMBOL;
845 name_list[1].n_un.n_name = 0;
846 # else /* not HAVE_STRUCT_NLIST_N_UN_N_NAME */
847 name_list[0].n_name = LDAV_SYMBOL;
848 name_list[1].n_name = 0;
849 # endif /* not HAVE_STRUCT_NLIST_N_UN_N_NAME */
850 # endif /* NLIST_STRUCT */
851
852 # ifndef SUNOS_5
853 if (
854 # if !defined (_AIX)
855 nlist (KERNEL_FILE, name_list)
856 # else /* _AIX */
857 knlist (name_list, 1, sizeof (name_list[0]))
858 # endif
859 >= 0)
860 /* Omit "&& name_list[0].n_type != 0 " -- it breaks on Sun386i. */
861 {
862 # ifdef FIXUP_KERNEL_SYMBOL_ADDR
863 FIXUP_KERNEL_SYMBOL_ADDR (name_list);
864 # endif
865 offset = name_list[0].n_value;
866 }
867 # endif /* !SUNOS_5 */
868 # else /* sgi */
869 ptrdiff_t ldav_off = sysmp (MP_KERNADDR, MPKA_AVENRUN);
870 if (ldav_off != -1)
871 offset = (long int) ldav_off & 0x7fffffff;
872 # endif /* sgi */
873 }
874
875 /* Make sure we have /dev/kmem open. */
876 if (!getloadavg_initialized)
877 {
878 # ifndef SUNOS_5
879 int fd = open ("/dev/kmem", O_RDONLY | O_CLOEXEC);
880 if (0 <= fd)
881 {
882 channel = fd;
883 getloadavg_initialized = true;
884 }
885 # else /* SUNOS_5 */
886 /* We pass 0 for the kernel, corefile, and swapfile names
887 to use the currently running kernel. */
888 kd = kvm_open (0, 0, 0, O_RDONLY, 0);
889 if (kd != NULL)
890 {
891 /* nlist the currently running kernel. */
892 kvm_nlist (kd, name_list);
893 offset = name_list[0].n_value;
894 getloadavg_initialized = true;
895 }
896 # endif /* SUNOS_5 */
897 }
898
899 /* If we can, get the load average values. */
900 if (offset && getloadavg_initialized)
901 {
902 /* Try to read the load. */
903 # ifndef SUNOS_5
904 if (lseek (channel, offset, 0) == -1L
905 || read (channel, (char *) load_ave, sizeof (load_ave))
906 != sizeof (load_ave))
907 {
908 close (channel);
909 getloadavg_initialized = false;
910 }
911 # else /* SUNOS_5 */
912 if (kvm_read (kd, offset, (char *) load_ave, sizeof (load_ave))
913 != sizeof (load_ave))
914 {
915 kvm_close (kd);
916 getloadavg_initialized = false;
917 }
918 # endif /* SUNOS_5 */
919 }
920
921 if (offset == 0 || !getloadavg_initialized)
922 {
923 errno = ENOTSUP;
924 return -1;
925 }
926 # endif /* ! defined LDAV_DONE && defined LOAD_AVE_TYPE && ! defined __VMS */
927
928 # if !defined (LDAV_DONE) && defined (LOAD_AVE_TYPE) /* Including VMS. */
929 if (nelem > 0)
930 loadavg[elem++] = LDAV_CVT (load_ave[0]);
931 if (nelem > 1)
932 loadavg[elem++] = LDAV_CVT (load_ave[1]);
933 if (nelem > 2)
934 loadavg[elem++] = LDAV_CVT (load_ave[2]);
935
936 # define LDAV_DONE
937 # endif /* !LDAV_DONE && LOAD_AVE_TYPE */
938
939 # if !defined LDAV_DONE
940 errno = ENOSYS;
941 elem = -1;
942 # endif
943 return elem;
944 }