text: /****************************************************************************
   * Copyright (c) 1998,2001,2003 Free Software Foundation, Inc.              *
   *                                                                          *
   * Permission is hereby granted, free of charge, to any person obtaining a  *
   * copy of this software and associated documentation files (the            *
   * "Software"), to deal in the Software without restriction, including      *
   * without limitation the rights to use, copy, modify, merge, publish,      *
   * distribute, distribute with modifications, sublicense, and/or sell       *
   * copies of the Software, and to permit persons to whom the Software is    *
   * furnished to do so, subject to the following conditions:                 *
   *                                                                          *
   * The above copyright notice and this permission notice shall be included  *
   * in all copies or substantial portions of the Software.                   *
   *                                                                          *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
   * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
   * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
   * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
   * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
   * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
   *                                                                          *
   * Except as contained in this notice, the name(s) of the above copyright   *
   * holders shall not be used in advertising or otherwise to promote the     *
   * sale, use or other dealings in this Software without prior written       *
   * authorization.                                                           *
   ****************************************************************************/
  
  /****************************************************************************
   *  Author: Thomas E. Dickey <dickey@clark.net> 1998,2000,2001              *
   ****************************************************************************/
  
  #include <curses.priv.h>
  #include <tic.h>
  #include <nc_alloc.h>
  
  MODULE_ID("$Id: access.c,v 1.10 2003/07/05 19:31:28 tom Exp $")
  
  #define LOWERCASE(c) ((isalpha(UChar(c)) && isupper(UChar(c))) ? tolower(UChar(c)) : (c))
  
  NCURSES_EXPORT(char *)
  _nc_rootname(char *path)
  {
      char *result = _nc_basename(path);
  #if !defined(MIXEDCASE_FILENAMES) || defined(PROG_EXT)
      static char *temp;
      char *s;
  
      temp = strdup(result);
      result = temp;
  #if !defined(MIXEDCASE_FILENAMES)
      int n;
      for (s = result; *s != '\0'; ++s) {
  	*s = LOWERCASE(*s);
      }
  #endif
  #if defined(PROG_EXT)
      if ((s = strrchr(result, '.')) != 0) {
  	if (!strcmp(s, PROG_EXT))
  	    *s = '\0';
      }
  #endif
  #endif
      return result;
  }
  
  /*
   * Return index of the basename
   */
  NCURSES_EXPORT(unsigned)
  _nc_pathlast(const char *path)
  {
      const char *test = strrchr(path, '/');
  #ifdef __EMX__
      if (test == 0)
  	test = strrchr(path, '\\');
  #endif
      if (test == 0)
  	test = path;
      else
  	test++;
      return (test - path);
  }
  
  NCURSES_EXPORT(char *)
  _nc_basename(char *path)
  {
      return path + _nc_pathlast(path);
  }
  
  NCURSES_EXPORT(int)
  _nc_access(const char *path, int mode)
  {
      if (access(path, mode) < 0) {
  	if ((mode & W_OK) != 0
  	    && errno == ENOENT
  	    && strlen(path) < PATH_MAX) {
  	    char head[PATH_MAX];
  	    char *leaf = _nc_basename(strcpy(head, path));
  
  	    if (leaf == 0)
  		leaf = head;
  	    *leaf = '\0';
  	    if (head == leaf)
  		(void) strcpy(head, ".");
  
  	    return access(head, R_OK | W_OK | X_OK);
  	}
  	return -1;
      }
      return 0;
  }
  
  #ifndef USE_ROOT_ENVIRON
  /*
   * Returns true if we allow application to use environment variables that are
   * used for searching lists of directories, etc.
   */
  NCURSES_EXPORT(int)
  _nc_env_access(void)
  {
  #if HAVE_ISSETUGID
      if (issetugid())
  	return FALSE;
  #elif HAVE_GETEUID && HAVE_GETEGID
      if (getuid() != geteuid()
  	|| getgid() != getegid())
  	return FALSE;
  #endif
      return getuid() != 0 && geteuid() != 0;	/* ...finally, disallow root */
  }
  #endif
  