source: trunk/yat/utility/FileUtil.cc @ 2121

// $Id: FileUtil.cc 2121 2009-12-13 16:17:07Z peter $

/*
  Copyright (C) 2004 Jari Häkkinen
  Copyright (C) 2005 Peter Johansson
  Copyright (C) 2006 Jari Häkkinen
  Copyright (C) 2007, 2008 Jari Häkkinen, Peter Johansson
  Copyright (C) 2009 Peter Johansson

  This file is part of the yat library, http://dev.thep.lu.se/yat

  The yat library 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 3 of the
  License, or (at your option) any later version.

  The yat library 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 yat. If not, see <http://www.gnu.org/licenses/>.
*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "FileUtil.h"

#include "Exception.h"

#include <cerrno>
#include <cstddef>
#include <cstring>
#include <iostream>
#include <stdexcept>
#include <sstream>
#include <string>

#include <sys/stat.h>
#include <unistd.h>


namespace theplu {
namespace yat {
namespace utility {


  FileUtil::FileUtil(const std::string& path)
    : path_(path)
  {
  }


  int FileUtil::permissions(const std::string& bits) const
  {
    std::string tryme=path_;
    if (!exists()) {
      std::string::size_type pos=path_.find_last_of('/');
      tryme = ( (pos!=std::string::npos) ? path_.substr(0,pos) : "." );
    }

    int mode=0;
    bool ok = true;
    for (size_t i=0; i<bits.length(); i++)
      switch (bits[i]) {
          case 'r':
            mode|=R_OK;
            break;
          case 'w':
            mode|=W_OK;
            break;
          case 'x':
            mode|=X_OK;
            break;
          case 'd':
            struct stat nodestat;
            stat(tryme.c_str(),&nodestat);
            if (!S_ISDIR(nodestat.st_mode))
              ok = false;
            break;
          default:
            throw std::invalid_argument("FileUtil::permission: "+bits);
      }
    if (!ok)
      return -1;
    return access(tryme.c_str(),mode);
  }


  bool FileUtil::exists(void) const
  {
    struct stat statt;
    return exists_common(stat(path_.c_str(),&statt));
  }


  bool FileUtil::exists_common(bool failed) const
  {
    if ( failed && (errno!=ENOENT) ) {
      std::stringstream ss;
      ss << "stat(2) call failed with errno: " << errno << "\n"
         << strerror(errno);
      throw IO_error(ss.str());
    }
    return !failed;
  }


  bool FileUtil::lexists(void) const
  {
    struct stat statt;
    return exists_common(lstat(path_.c_str(),&statt));
  }


  const std::string& FileUtil::path(void) const
  {
    return path_;
  }

}}} // of namespace utility, yat, and theplu