source: trunk/essentials/app-arch/cpio/src/makepath.c

/* makepath.c -- Ensure that a directory path exists.
   Copyright (C) 1990, 2006 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public
   License along with this program; if not, write to the Free
   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301 USA.  */

/* Written by David MacKenzie <djm@gnu.ai.mit.edu> and
   Jim Meyering <meyering@cs.utexas.edu>.  */

/* This copy of makepath is almost like the fileutils one, but has
   changes for HPUX CDF's.  Maybe the 2 versions of makepath can
   come together again in the future.  */

#include <system.h>

#ifdef __GNUC__
#define alloca __builtin_alloca
#else
#ifdef HAVE_ALLOCA_H
#include <alloca.h>
#else
#ifdef _AIX
 #pragma alloca
#else
char *alloca ();
#endif
#endif
#endif

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#if !defined(S_ISDIR) && defined(S_IFDIR)
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif

#include <errno.h>
#ifdef STDC_HEADERS
#include <stdlib.h>
#else
extern int errno;
#endif

#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
#include <string.h>
#ifndef index
#define index strchr
#endif
#else
#include <strings.h>
#endif

/* Ensure that the directory ARGPATH exists.
   Remove any trailing slashes from ARGPATH before calling this function.

   Make any leading directories that don't already exist, with
   permissions PARENT_MODE.
   If the last element of ARGPATH does not exist, create it as
   a new directory with permissions MODE.
   If OWNER and GROUP are non-negative, make them the UID and GID of
   created directories.
   If VERBOSE_FMT_STRING is nonzero, use it as a printf format
   string for printing a message after successfully making a directory,
   with the name of the directory that was just made as an argument.

   Return 0 if ARGPATH exists as a directory with the proper
   ownership and permissions when done, otherwise 1.  */

int
make_path (char *argpath,
           int mode,
           int parent_mode,
           uid_t owner,
           gid_t group,
           char *verbose_fmt_string)
{
  char *dirpath;                /* A copy we can scribble NULs on.  */
  struct stat stats;
  int retval = 0;
  int oldmask = umask (0);
  dirpath = alloca (strlen (argpath) + 1);
  strcpy (dirpath, argpath);

  if (stat (dirpath, &stats))
    {
      char *slash;
      int tmp_mode;             /* Initial perms for leading dirs.  */
      int re_protect;           /* Should leading dirs be unwritable? */
      struct ptr_list
      {
        char *dirname_end;
        struct ptr_list *next;
      };
      struct ptr_list *p, *leading_dirs = NULL;

      /* If leading directories shouldn't be writable or executable,
         or should have set[ug]id or sticky bits set and we are setting
         their owners, we need to fix their permissions after making them.  */
      if (((parent_mode & 0300) != 0300)
          || (owner != (uid_t) -1 && group != (gid_t) -1
              && (parent_mode & 07000) != 0))
        {
          tmp_mode = 0700;
          re_protect = 1;
        }
      else
        {
          tmp_mode = parent_mode;
          re_protect = 0;
        }

      slash = dirpath;
      while (*slash == '/')
        slash++;
      while ((slash = strchr (slash, '/')))
        {
#ifdef HPUX_CDF
          int   iscdf;
          iscdf = 0;
#endif
          *slash = '\0';
          if (stat (dirpath, &stats))
            {
#ifdef HPUX_CDF
              /* If this component of the pathname ends in `+' and is
                 followed by 2 `/'s, then this is a CDF.  We remove the
                 `+' from the name and create the directory.  Later
                 we will "hide" the directory.  */
              if ( (*(slash +1) == '/') && (*(slash -1) == '+') )
                { 
                  iscdf = 1;
                  *(slash -1) = '\0';
                }
#endif
              if (mkdir (dirpath, tmp_mode))
                {
                  error (0, errno, _("cannot make directory `%s'"), dirpath);
                  umask (oldmask);
                  return 1;
                }
              else
                {
                  if (verbose_fmt_string != NULL)
                    error (0, 0, verbose_fmt_string, dirpath);

                  if (owner != (uid_t) -1 && group != (gid_t) -1
                      && chown (dirpath, owner, group)
#ifdef AFS
                      && errno != EPERM
#endif
                      )
                    {
                      chown_error_details (dirpath, owner, group);
                      retval = 1;
                    }
                  if (re_protect)
                    {
                      struct ptr_list *new = (struct ptr_list *)
                        alloca (sizeof (struct ptr_list));
                      new->dirname_end = slash;
                      new->next = leading_dirs;
                      leading_dirs = new;
                    }
#ifdef HPUX_CDF
                  if (iscdf)
                    {
                      /*  If this is a CDF, "hide" the directory by setting
                          its hidden/setuid bit.  Also add the `+' back to
                          its name (since once it's "hidden" we must refer
                          to as `name+' instead of `name').  */
                      chmod (dirpath, 04700);
                      *(slash - 1) = '+';
                    }
#endif
                }
            }
          else if (!S_ISDIR (stats.st_mode))
            {
              error (0, 0, _("`%s' exists but is not a directory"), dirpath);
              umask (oldmask);
              return 1;
            }

          *slash++ = '/';

          /* Avoid unnecessary calls to `stat' when given
             pathnames containing multiple adjacent slashes.  */
          while (*slash == '/')
            slash++;
        }

      /* We're done making leading directories.
         Make the final component of the path. */

      if (mkdir (dirpath, mode))
        {
          /* In some cases, if the final component in dirpath was `.' then we 
             just got an EEXIST error from that last mkdir().  If that's
             the case, ignore it.  */
          if ( (errno != EEXIST) ||
               (stat (dirpath, &stats) != 0) ||
               (!S_ISDIR (stats.st_mode) ) )
            {
              error (0, errno, _("cannot make directory `%s'"), dirpath);
              umask (oldmask);
              return 1;
            }
        }
      if (verbose_fmt_string != NULL)
        error (0, 0, verbose_fmt_string, dirpath);

      if (owner != (uid_t) -1 && group != (gid_t) -1)
        {
          if (chown (dirpath, owner, group)
#ifdef AFS
              && errno != EPERM
#endif
              )
            {
              chown_error_details (dirpath, owner, group);
              retval = 1;
            }
        }
      /* chown may have turned off some permission bits we wanted.  */
      if ((mode & 07000) != 0 && chmod (dirpath, mode))
        {
          chmod_error_details (dirpath, mode);
          retval = 1;
        }

      /* If the mode for leading directories didn't include owner "wx"
         privileges, we have to reset their protections to the correct
         value.  */
      for (p = leading_dirs; p != NULL; p = p->next)
        {
          *p->dirname_end = '\0';
#if 0
          /* cpio always calls make_path with parent mode 0700, so
             we don't have to do this.  If we ever do have to do this,
             we have to stat the directory first to get the setuid
             bit so we don't break HP CDF's.  */
          if (chmod (dirpath, parent_mode))
            {
              chmod_error_details (dirpath, parent_mode);
              retval = 1;
            }
#endif

        }
    }
  else
    {
      /* We get here if the entire path already exists.  */

      if (!S_ISDIR (stats.st_mode))
        {
          error (0, 0, _("`%s' exists but is not a directory"), dirpath);
          umask (oldmask);
          return 1;
        }

      /* chown must precede chmod because on some systems,
         chown clears the set[ug]id bits for non-superusers,
         resulting in incorrect permissions.
         On System V, users can give away files with chown and then not
         be able to chmod them.  So don't give files away.  */

      if (owner != (uid_t) -1 && group != (gid_t) -1
          && chown (dirpath, owner, group)
#ifdef AFS
          && errno != EPERM
#endif
          )
        {
          chown_error_details (dirpath, owner, group);
          retval = 1;
        }
      if (chmod (dirpath, mode))
        {
          chmod_error_details (dirpath, mode);
          retval = 1;
        }
    }

  umask (oldmask);
  return retval;
}