lib/libutil/kinfo_getvmobject.c

   1 /*
   2  * Copyright (c) 2013 Hudson River Trading LLC
   3  * Written by: John H. Baldwin <jhb@FreeBSD.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include <sys/types.h>
  32 #include <sys/sysctl.h>
  33 #include <sys/user.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36
  37 #include "libutil.h"
  38
  39 struct kinfo_vmobject *
  40 kinfo_getvmobject(int *cntp)
  41 {
  42         char *buf, *bp, *ep;
  43         struct kinfo_vmobject *kvo, *list, *kp;
  44         size_t len;
  45         int cnt, i;
  46
  47         buf = NULL;
  48         for (i = 0; i < 3; i++) {
  49                 if (sysctlbyname("vm.objects", NULL, &len, NULL, 0) < 0)
  50                         return (NULL);
  51                 buf = reallocf(buf, len);
  52                 if (buf == NULL)
  53                         return (NULL);
  54                 if (sysctlbyname("vm.objects", buf, &len, NULL, 0) == 0)
  55                         goto unpack;
  56                 if (errno != ENOMEM) {
  57                         free(buf);
  58                         return (NULL);
  59                 }
  60         }
  61         free(buf);
  62         return (NULL);
  63
  64 unpack:
  65         /* Count items */
  66         cnt = 0;
  67         bp = buf;
  68         ep = buf + len;
  69         while (bp < ep) {
  70                 kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
  71                 bp += kvo->kvo_structsize;
  72                 cnt++;
  73         }
  74
  75         list = calloc(cnt, sizeof(*list));
  76         if (list == NULL) {
  77                 free(buf);
  78                 return (NULL);
  79         }
  80
  81         /* Unpack */
  82         bp = buf;
  83         kp = list;
  84         while (bp < ep) {
  85                 kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
  86                 memcpy(kp, kvo, kvo->kvo_structsize);
  87                 bp += kvo->kvo_structsize;
  88                 kp->kvo_structsize = sizeof(*kp);
  89                 kp++;
  90         }
  91         free(buf);
  92         *cntp = cnt;
  93         return (list);
  94 }