/*
 *
 *   scan.c scan a directory (on a removable file) for a valid
 *      Volume name. If found, open the file for append.
 *
 *    Kern Sibbald, MMVI
 *
 *   Version $Id: scan.c 4992 2007-06-07 14:46:43Z kerns $
 */
/*
   Bacula® - The Network Backup Solution

   Copyright (C) 2006-2006 Free Software Foundation Europe e.V.

   The main author of Bacula is Kern Sibbald, with contributions from
   many others, a complete list can be found in the file AUTHORS.
   This program is Free Software; you can redistribute it and/or
   modify it under the terms of version two of the GNU General Public
   License as published by the Free Software Foundation and included
   in the file LICENSE.

   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.

   Bacula® is a registered trademark of John Walker.
   The licensor of Bacula is the Free Software Foundation Europe
   (FSFE), Fiduciary Program, Sumatrastrasse 25, 8006 Zürich,
   Switzerland, email:ftf@fsfeurope.org.
*/

#include "bacula.h"
#include "stored.h"

/* Forward referenced functions */
static bool is_volume_name_legal(char *name);


bool DEVICE::scan_dir_for_volume(DCR *dcr)
{
   DIR* dp;
   struct dirent *entry, *result;
   int name_max;
   char *mount_point;
   VOLUME_CAT_INFO dcrVolCatInfo, devVolCatInfo;
   char VolumeName[MAX_NAME_LENGTH];
   struct stat statp;
   bool found = false;
   POOL_MEM fname(PM_FNAME);
   bool need_slash = false;
   int len;

   dcrVolCatInfo = dcr->VolCatInfo;     /* structure assignment */
   devVolCatInfo = VolCatInfo;          /* structure assignment */
   bstrncpy(VolumeName, dcr->VolumeName, sizeof(VolumeName));

   name_max = pathconf(".", _PC_NAME_MAX);
   if (name_max < 1024) {
      name_max = 1024;
   }

   if (device->mount_point) {
      mount_point = device->mount_point;
   } else {
      mount_point = device->device_name;
   }
      
   if (!(dp = opendir(mount_point))) {
      berrno be;
      dev_errno = errno;
      Dmsg3(29, "scan_dir_for_vol: failed to open dir %s (dev=%s), ERR=%s\n", 
            mount_point, print_name(), be.bstrerror());
      goto get_out;
   }
   
   len = strlen(mount_point);
   if (len > 0) {
      need_slash = !IsPathSeparator(mount_point[len - 1]);
   }
   entry = (struct dirent *)malloc(sizeof(struct dirent) + name_max + 1000);
   for ( ;; ) {
      if ((readdir_r(dp, entry, &result) != 0) || (result == NULL)) {
         dev_errno = EIO;
         Dmsg2(129, "scan_dir_for_vol: failed to find suitable file in dir %s (dev=%s)\n", 
               mount_point, print_name());
         break;
      }
      if (strcmp(result->d_name, ".") == 0 || 
          strcmp(result->d_name, "..") == 0) {
         continue;
      }
       
      if (!is_volume_name_legal(result->d_name)) {
         continue;
      }
      pm_strcpy(fname, mount_point);
      if (need_slash) {
         pm_strcat(fname, "/");
      }
      pm_strcat(fname, result->d_name);
      if (lstat(fname.c_str(), &statp) != 0 ||
          !S_ISREG(statp.st_mode)) {
         continue;                 /* ignore directories & special files */
      }

      /*
       * OK, we got a different volume mounted. First save the
       *  requested Volume info (dcr) structure, then query if
       *  this volume is really OK. If not, put back the desired
       *  volume name, mark it not in changer and continue.
       */
      /* Check if this is a valid Volume in the pool */
      bstrncpy(dcr->VolumeName, result->d_name, sizeof(dcr->VolumeName));
      if (!dir_get_volume_info(dcr, GET_VOL_INFO_FOR_WRITE)) {
         continue;
      }
      /* This was not the volume we expected, but it is OK with
       * the Director, so use it.
       */
      VolCatInfo = dcr->VolCatInfo;       /* structure assignment */
      found = true;
      break;                /* got a Volume */
   }
   free(entry);
   closedir(dp);
   
get_out:
   if (!found) {
      /* Restore VolumeName we really wanted */
      bstrncpy(dcr->VolumeName, VolumeName, sizeof(dcr->VolumeName));
      dcr->VolCatInfo = dcrVolCatInfo;     /* structure assignment */
      VolCatInfo = devVolCatInfo;          /* structure assignment */
   }
   sm_check(__FILE__, __LINE__, false);
   return found;
}

/*
 * Check if the Volume name has legal characters
 * If ua is non-NULL send the message
 */
static bool is_volume_name_legal(char *name)
{
   int len;
   const char *p;
   const char *accept = ":.-_";

   /* Restrict the characters permitted in the Volume name */
   for (p=name; *p; p++) {
      if (B_ISALPHA(*p) || B_ISDIGIT(*p) || strchr(accept, (int)(*p))) {
         continue;
      }
      return false;
   }
   len = strlen(name);
   if (len >= MAX_NAME_LENGTH) {
      return false;
   }
   if (len == 0) {
      return false;
   }
   return true;
}