sbin/sysctl/pathconf.c

   1 /*
   2  * Copyright (c) 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)pathconf.c       8.1 (Berkeley) 6/6/93
  35  * $FreeBSD: src/sbin/sysctl/pathconf.c,v 1.4 1999/08/28 00:14:30 peter Exp $
  36  * $DragonFly: src/sbin/sysctl/pathconf.c,v 1.5 2004/12/18 22:43:46 swildner Exp $
  37  */
  38
  39 #include <sys/param.h>
  40 #include <sys/sysctl.h>
  41 #include <sys/unistd.h>
  42
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49
  50 #define PC_NAMES { \
  51         { 0, 0 }, \
  52         { "link_max", CTLTYPE_INT }, \
  53         { "max_canon", CTLTYPE_INT }, \
  54         { "max_input", CTLTYPE_INT }, \
  55         { "name_max", CTLTYPE_INT }, \
  56         { "path_max", CTLTYPE_INT }, \
  57         { "pipe_buf", CTLTYPE_INT }, \
  58         { "chown_restricted", CTLTYPE_INT }, \
  59         { "no_trunc", CTLTYPE_INT }, \
  60         { "vdisable", CTLTYPE_INT }, \
  61 }
  62 #define PC_MAXID 10
  63
  64 struct ctlname pcnames[] = PC_NAMES;
  65 char names[BUFSIZ];
  66
  67 struct list {
  68         struct  ctlname *list;
  69         int     size;
  70 };
  71 struct list pclist = { pcnames, PC_MAXID };
  72
  73 int     Aflag, aflag, nflag, wflag, stdinflag;
  74
  75 int findname(char *, char *, char**, struct list *);
  76 void listall(char *, struct list *);
  77 void parse(char *, char *, int);
  78 static void usage(void);
  79
  80 int
  81 main(int argc, char **argv)
  82 {
  83         char *path;
  84         int ch;
  85
  86         while ((ch = getopt(argc, argv, "Aan")) != -1) {
  87                 switch (ch) {
  88
  89                 case 'A':
  90                         Aflag = 1;
  91                         break;
  92
  93                 case 'a':
  94                         aflag = 1;
  95                         break;
  96
  97                 case 'n':
  98                         nflag = 1;
  99                         break;
 100
 101                 default:
 102                         usage();
 103                 }
 104         }
 105         argc -= optind;
 106         argv += optind;
 107
 108         if (argc == 0)
 109                 usage();
 110         path = *argv++;
 111         if (strcmp(path, "-") == 0)
 112                 stdinflag = 1;
 113         argc--;
 114         if (Aflag || aflag) {
 115                 listall(path, &pclist);
 116                 exit(0);
 117         }
 118         if (argc == 0)
 119                 usage();
 120         while (argc-- > 0)
 121                 parse(path, *argv, 1);
 122         exit(0);
 123 }
 124
 125 /*
 126  * List all variables known to the system.
 127  */
 128 void
 129 listall(char *path, struct list *lp)
 130 {
 131         int lvl2;
 132
 133         if (lp->list == 0)
 134                 return;
 135         for (lvl2 = 0; lvl2 < lp->size; lvl2++) {
 136                 if (lp->list[lvl2].ctl_name == 0)
 137                         continue;
 138                 parse(path, lp->list[lvl2].ctl_name, Aflag);
 139         }
 140 }
 141
 142 /*
 143  * Parse a name into an index.
 144  * Lookup and print out the attribute if it exists.
 145  */
 146 void
 147 parse(char *pathname, char *string, int flags)
 148 {
 149         int indx, value;
 150         char *bufp, buf[BUFSIZ];
 151
 152         bufp = buf;
 153         snprintf(buf, BUFSIZ, "%s", string);
 154         if ((indx = findname(string, "top", &bufp, &pclist)) == -1)
 155                 return;
 156         if (bufp) {
 157                 warnx("name %s in %s is unknown", *bufp, string);
 158                 return;
 159         }
 160         if (stdinflag)
 161                 value = fpathconf(0, indx);
 162         else
 163                 value = pathconf(pathname, indx);
 164         if (value == -1) {
 165                 if (flags == 0)
 166                         return;
 167                 switch (errno) {
 168                 case EOPNOTSUPP:
 169                         warnx("%s: value is not available", string);
 170                         return;
 171                 case ENOTDIR:
 172                         warnx("%s: specification is incomplete", string);
 173                         return;
 174                 case ENOMEM:
 175                         warnx("%s: type is unknown to this program", string);
 176                         return;
 177                 default:
 178                         warn("%s", string);
 179                         return;
 180                 }
 181         }
 182         if (!nflag)
 183                 fprintf(stdout, "%s = ", string);
 184         fprintf(stdout, "%d\n", value);
 185 }
 186
 187 /*
 188  * Scan a list of names searching for a particular name.
 189  */
 190 int
 191 findname(char *string, char *level, char **bufp, struct list *namelist)
 192         char *string;
 193         char *level;
 194         char **bufp;
 195         struct list *namelist;
 196 {
 197         char *name;
 198         int i;
 199
 200         if (namelist->list == 0 || (name = strsep(bufp, ".")) == NULL) {
 201                 warnx("%s: incomplete specification", string);
 202                 return (-1);
 203         }
 204         for (i = 0; i < namelist->size; i++)
 205                 if (namelist->list[i].ctl_name != NULL &&
 206                     strcmp(name, namelist->list[i].ctl_name) == 0)
 207                         break;
 208         if (i == namelist->size) {
 209                 warnx("%s level name %s in %s is invalid", level, name, string);
 210                 return (-1);
 211         }
 212         return (i);
 213 }
 214
 215 static void
 216 usage(void)
 217 {
 218
 219         fprintf(stderr, "%s\n%s\n%s\n",
 220                 "usage: pathname [-n] variable ...",
 221                 "       pathname [-n] -a",
 222                 "       pathname [-n] -A");
 223         exit(1);
 224 }