lib/libkinfo/kinfo_file.c

   1 /*
   2  * Copyright (c) 2004 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Joerg Sonnenberger <joerg@bec.de>.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/lib/libkinfo/kinfo_file.c,v 1.4 2004/12/21 15:07:42 joerg Exp $
  35  */
  36
  37 #include <sys/param.h>
  38 #include <sys/sysctl.h>
  39
  40 #include <err.h>
  41 #include <errno.h>
  42 #include <kinfo.h>
  43 #include <stdlib.h>
  44
  45 #define KERN_FILE_SYSCTL "kern.file"
  46
  47 int
  48 kinfo_get_files(struct kinfo_file **file_buf, size_t *len)
  49 {
  50         int retval;
  51         void *buf;
  52         size_t new_len;
  53
  54         retval = sysctlbyname(KERN_FILE_SYSCTL, NULL, &new_len, NULL, 0);
  55         if (retval)
  56                 return(retval);
  57         if ((buf = malloc(new_len)) == NULL)
  58                 return(ENOMEM);
  59         retval = sysctlbyname(KERN_FILE_SYSCTL, buf, &new_len, NULL, 0);
  60         if (retval) {
  61                 free(buf);
  62                 return(retval);
  63         }
  64         /*
  65          * Shrink the buffer to the minimum size, this is not supposed
  66          * to fail.
  67          */
  68         if ((buf = reallocf(buf, new_len)) == NULL)
  69                 err(1, "realloc");
  70         if (new_len != 0 &&
  71             ((struct kinfo_file *)buf)->f_size != sizeof(struct kinfo_file)) {
  72                 warnx("kernel size of struct kinfo_file changed");
  73                 free(buf);
  74                 return(EOPNOTSUPP);
  75         }
  76         *len = new_len / sizeof(struct kinfo_file);
  77         *file_buf = buf;
  78         return(0);
  79 }
  80
  81 /* XXX convert kern.maxfiles to size_t */
  82 int
  83 kinfo_get_maxfiles(int *maxfiles)
  84 {
  85         size_t len = sizeof(*maxfiles);
  86
  87         return(sysctlbyname("kern.maxfiles", maxfiles, &len, NULL, 0));
  88 }
  89
  90 /* XXX convert kern.openfiles to size_t */
  91 int
  92 kinfo_get_openfiles(int *openfiles)
  93 {
  94         size_t len = sizeof(*openfiles);
  95
  96         return(sysctlbyname("kern.openfiles", openfiles, &len, NULL, 0));
  97 }