usr/src/lib/libproc/common/Pisprocdir.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #pragma ident   "%Z%%M% %I%     %E% SMI"
  27
  28 #include <string.h>
  29 #include <limits.h>
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32 #include "Pcontrol.h"
  33
  34 /*
  35  * Return TRUE iff dir is the /proc directory.
  36  */
  37 int
  38 Pisprocdir(struct ps_prochandle *Pr, const char *dir)
  39 {
  40         char path[PATH_MAX];
  41         struct stat statb;
  42         struct statvfs statvfsb;
  43
  44         if (*dir == '/')
  45                 (void) snprintf(path, sizeof (path), "%s/%d/root%s",
  46                     procfs_path, (int)Pr->pid, dir);
  47         else
  48                 (void) snprintf(path, sizeof (path), "%s/%d/cwd/%s",
  49                     procfs_path, (int)Pr->pid, dir);
  50
  51         /*
  52          * We can't compare the statb.st_fstype string to "proc" because
  53          * a loop-back mount of /proc would show "lofs" instead of "proc".
  54          * Instead we use the statvfs() f_basetype string.
  55          */
  56         return (stat(path, &statb) == 0 &&
  57             statvfs(path, &statvfsb) == 0 &&
  58             (statb.st_mode & S_IFMT) == S_IFDIR &&
  59             statb.st_ino == 2 &&
  60             strcmp(statvfsb.f_basetype, "proc") == 0);
  61 }