test/ipc/lib/rmobj.c

   1 /*
   2  * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/NoticeExplan/
  31  */
  32
  33 /**********************************************************
  34  *
  35  *    OS Testing - Silicon Graphics, Inc.
  36  *
  37  *    FUNCTION NAME     : rmobj()
  38  *
  39  *    FUNCTION TITLE    : Remove an object
  40  *
  41  *    SYNOPSIS:
  42  *      int rmobj(char *obj, char **errmsg)
  43  *
  44  *    AUTHOR            : Kent Rogers
  45  *
  46  *    INITIAL RELEASE   : UNICOS 7.0
  47  *
  48  *    USER DESCRIPTION
  49  *      This routine will remove the specified object.  If the specified
  50  *      object is a directory, it will recursively remove the directory
  51  *      and everything underneath it.  It assumes that it has privilege
  52  *      to remove everything that it tries to remove.  If rmobj() encounters
  53  *      any problems, and errmsg is not NULL, errmsg is set to point to a
  54  *      string explaining the error.
  55  *
  56  *    DETAILED DESCRIPTION
  57  *      Allocate space for the directory and its contents
  58  *      Open the directory to get access to what is in it
  59  *      Loop through the objects in the directory:
  60  *        If the object is not "." or "..":
  61  *          Determine the file type by calling lstat()
  62  *          If the object is not a directory:
  63  *            Remove the object with unlink()
  64  *         Else:
  65  *            Call rmobj(object) to remove the object's contents
  66  *            Determine the link count on object by calling lstat()
  67  *            If the link count >= 3:
  68  *              Remove the directory with unlink()
  69  *            Else
  70  *               Remove the directory with rmdir()
  71  *      Close the directory and free the pointers
  72  *
  73  *    RETURN VALUE
  74  *      If there are any problems, rmobj() will set errmsg (if it was not
  75  *      NULL) and return -1.  Otherwise it will return 0.
  76  *
  77  ************************************************************/
  78 #include <errno.h>         /* for errno */
  79 #include <stdio.h>         /* for NULL */
  80 #include <stdlib.h>        /* for malloc() */
  81 #include <string.h>        /* for string function */
  82 #include <limits.h>        /* for PATH_MAX */
  83 #include <sys/types.h>     /* for opendir(), readdir(), closedir(), stat() */
  84 #include <sys/stat.h>      /* for [l]stat() */
  85 #include <dirent.h>        /* for opendir(), readdir(), closedir() */
  86 #include <unistd.h>        /* for rmdir(), unlink() */
  87 #include "rmobj.h"
  88
  89 #define SYSERR strerror(errno)
  90
  91 int
  92 rmobj(char *obj, char **errmsg)
  93 {
  94    int           ret_val = 0;       /* return value from this routine */
  95    DIR           *dir;              /* pointer to a directory */
  96    struct dirent *dir_ent;          /* pointer to directory entries */
  97    char          dirobj[PATH_MAX];  /* object inside directory to modify */
  98    struct stat   statbuf;           /* used to hold stat information */
  99    static char   err_msg[1024];     /* error message */
 100
 101    /* Determine the file type */
 102    if ( lstat(obj, &statbuf) < 0 ) {
 103       if ( errmsg != NULL ) {
 104          sprintf(err_msg, "lstat(%s) failed; errno=%d: %s",
 105                  obj, errno, SYSERR);
 106          *errmsg = err_msg;
 107       }
 108       return -1;
 109    }
 110
 111    /* Take appropriate action, depending on the file type */
 112    if ( (statbuf.st_mode & S_IFMT) == S_IFDIR ) {
 113       /* object is a directory */
 114
 115       /* Do NOT perform the request if the directory is "/" */
 116       if ( !strcmp(obj, "/") ) {
 117          if ( errmsg != NULL ) {
 118             sprintf(err_msg, "Cannot remove /");
 119             *errmsg = err_msg;
 120          }
 121          return -1;
 122       }
 123
 124       /* Open the directory to get access to what is in it */
 125       if ( (dir = opendir(obj)) == NULL ) {
 126          if ( rmdir(obj) != 0 ) {
 127             if ( errmsg != NULL ) {
 128                sprintf(err_msg, "rmdir(%s) failed; errno=%d: %s",
 129                        obj, errno, SYSERR);
 130                *errmsg = err_msg;
 131             }
 132             return -1;
 133          } else {
 134             return 0;
 135          }
 136       }
 137
 138       /* Loop through the entries in the directory, removing each one */
 139       for ( dir_ent = (struct dirent *)readdir(dir);
 140             dir_ent != NULL;
 141             dir_ent = (struct dirent *)readdir(dir)) {
 142
 143          /* Don't remove "." or ".." */
 144          if ( !strcmp(dir_ent->d_name, ".") || !strcmp(dir_ent->d_name, "..") )
 145             continue;
 146
 147          /* Recursively call this routine to remove the current entry */
 148          sprintf(dirobj, "%s/%s", obj, dir_ent->d_name);
 149          if ( rmobj(dirobj, errmsg) != 0 )
 150             ret_val = -1;
 151       }
 152
 153       /* Close the directory */
 154       closedir(dir);
 155
 156       /* If there were problems removing an entry, don't attempt to
 157          remove the directory itself */
 158       if ( ret_val == -1 )
 159          return -1;
 160
 161       /* Get the link count, now that all the entries have been removed */
 162       if ( lstat(obj, &statbuf) < 0 ) {
 163          if ( errmsg != NULL ) {
 164             sprintf(err_msg, "lstat(%s) failed; errno=%d: %s",
 165                     obj, errno, SYSERR);
 166             *errmsg = err_msg;
 167          }
 168          return -1;
 169       }
 170
 171       /* Remove the directory itself */
 172       if ( statbuf.st_nlink >= 3 ) {
 173          /* The directory is linked; unlink() must be used */
 174          if ( unlink(obj) < 0 ) {
 175             if ( errmsg != NULL ) {
 176                sprintf(err_msg, "unlink(%s) failed; errno=%d: %s",
 177                        obj, errno, SYSERR);
 178                *errmsg = err_msg;
 179             }
 180             return -1;
 181          }
 182       } else {
 183          /* The directory is not linked; rmdir() can be used */
 184          if ( rmdir(obj) < 0 ) {
 185             if ( errmsg != NULL ) {
 186                sprintf(err_msg, "remove(%s) failed; errno=%d: %s",
 187                        obj, errno, SYSERR);
 188                *errmsg = err_msg;
 189             }
 190             return -1;
 191          }
 192       }
 193    } else {
 194       /* object is not a directory; just use unlink() */
 195       if ( unlink(obj) < 0 ) {
 196          if ( errmsg != NULL ) {
 197             sprintf(err_msg, "unlink(%s) failed; errno=%d: %s",
 198                     obj, errno, SYSERR);
 199             *errmsg = err_msg;
 200          }
 201          return -1;
 202       }
 203    }  /* if obj is a directory */
 204
 205    /*
 206     * Everything must have went ok.
 207     */
 208    return 0;
 209 }  /* rmobj() */