open_file.c

   1 /*
   2  * User FTP Server,  Share folders over FTP without being root.
   3  * Copyright (C) 2008  Isaac Jurado
   4  *
   5  * This program is free software; you can redistribute it and/or modify it under
   6  * the terms of the GNU General Public License as published by the Free Software
   7  * Foundation; either version 2 of the License, or (at your option) any later
   8  * version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  12  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  13  * details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  18  */
  19
  20 #include "uftps.h"
  21 #ifdef __MINGW32__
  22 #  include "hase.h"
  23 #else
  24 #  include <sys/stat.h>
  25 #  include <unistd.h>
  26 #  include <fcntl.h>
  27 #endif
  28
  29
  30 /*
  31  * Open the file specified in the argument after performing various checks.
  32  * Returns the opened file descriptor when successful, -1 on error.  The total
  33  * size of the file is stored in "file_size".
  34  *
  35  * This function is the common code between all send_file() implementations.
  36  * Note that, on error, everybody is notified so the invocation to this function
  37  * is as simple as possible.
  38  */
  39 int open_file (off_t *file_size)
  40 {
  41         int          f, e;
  42         struct stat  s;
  43
  44         if (SS.arg == NULL)
  45         {
  46                 reply_c("501 Argument required.\r\n");
  47                 return -1;
  48         }
  49         expand_arg();
  50
  51         /* Avoid following symlinks, as usual */
  52         e = lstat(SS.arg, &s);
  53         if (e == -1 || !S_ISREG(s.st_mode))
  54         {
  55                 if (e == -1)
  56                         error("Stating file %s", SS.arg);
  57                 else
  58                         warning("%s is not a regular file", SS.arg);
  59                 reply_c("550 Not a file.\r\n");
  60                 return -1;
  61         }
  62         *file_size = s.st_size;
  63
  64         f = open(SS.arg, O_RDONLY);
  65         if (f == -1)
  66         {
  67                 error("Opening file %s", SS.arg);
  68                 reply_c("550 Could not open file.\r\n");
  69         }
  70
  71         return f;
  72 }
  73