C++ DEVICE::can_append方法代码示例

/*
 * Open the first part file.
 *  - Close the fd
 *  - Reopen the device
 */
static bool dvd_open_first_part(DCR *dcr, int mode)
{
   DEVICE *dev = dcr->dev;

   Dmsg5(29, "Enter: ==== open_first_part dev=%s Vol=%s mode=%d num_dvd_parts=%d append=%d\n", dev->print_name(), 
         dev->getVolCatName(), dev->openmode, dev->num_dvd_parts, dev->can_append());


   dev->close_part(dcr);

   Dmsg2(400, "Call dev->open(vol=%s, mode=%d)\n", dcr->getVolCatName(), 
         mode);
   Dmsg0(100, "Set part=1\n");
   dev->part = 1;
   dev->part_start = 0;

   if (dev->open(dcr, mode) < 0) {
      Dmsg0(400, "open dev() failed\n");
      return false;
   }
   Dmsg2(400, "Leave open_first_part state=%s append=%d\n", dev->is_open()?"open":"not open", dev->can_append());
   
   return true;
}

//.........这里部分代码省略.........
         dev->dblock(BST_DOING_ACQUIRE);

         dcr->VolumeName[0] = 0;
         Jmsg(jcr, M_INFO, 0, _("Media Type change.  New read device %s chosen.\n"),
            dev->print_name());
         Dmsg1(50, "Media Type change.  New read device %s chosen.\n", dev->print_name());
         bstrncpy(dcr->VolumeName, vol->VolumeName, sizeof(dcr->VolumeName));
         dcr->setVolCatName(vol->VolumeName);
         bstrncpy(dcr->media_type, vol->MediaType, sizeof(dcr->media_type));
         dcr->VolCatInfo.Slot = vol->Slot;
         dcr->VolCatInfo.InChanger = vol->Slot > 0;
         bstrncpy(dcr->pool_name, store->pool_name, sizeof(dcr->pool_name));
         bstrncpy(dcr->pool_type, store->pool_type, sizeof(dcr->pool_type));
      } else {
         /* error */
         Jmsg1(jcr, M_FATAL, 0, _("No suitable device found to read Volume \"%s\"\n"),
            vol->VolumeName);
         Dmsg1(rdbglvl, "No suitable device found to read Volume \"%s\"\n", vol->VolumeName);
         goto get_out;
      }
   }
   Dmsg2(rdbglvl, "MediaType dcr=%s dev=%s\n", dcr->media_type, dev->device->media_type);

   dev->clear_unload();

   if (dev->vol && dev->vol->is_swapping()) {
      dev->vol->set_slot(vol->Slot);
      Dmsg3(rdbglvl, "swapping: slot=%d Vol=%s dev=%s\n", dev->vol->get_slot(),
         dev->vol->vol_name, dev->print_name());
   }

   init_device_wait_timers(dcr);

   tape_previously_mounted = dev->can_read() || dev->can_append() ||
                             dev->is_labeled();
// tape_initially_mounted = tape_previously_mounted;

   /* Volume info is always needed because of VolParts */
   Dmsg1(rdbglvl, "dir_get_volume_info vol=%s\n", dcr->VolumeName);
   if (!dcr->dir_get_volume_info(GET_VOL_INFO_FOR_READ)) {
      Dmsg2(rdbglvl, "dir_get_vol_info failed for vol=%s: %s\n",
            dcr->VolumeName, jcr->errmsg);
      Jmsg1(jcr, M_WARNING, 0, "Read acquire: %s", jcr->errmsg);
   }
   dev->set_load();                /* set to load volume */

   for ( ;; ) {
      /* If not polling limit retries */
      if (!dev->poll && retry++ > 10) {
         break;
      }
      dev->clear_labeled();              /* force reread of label */
      if (job_canceled(jcr)) {
         char ed1[50];
         Mmsg1(dev->errmsg, _("Job %s canceled.\n"), edit_int64(jcr->JobId, ed1));
         Jmsg(jcr, M_INFO, 0, dev->errmsg);
         goto get_out;                /* error return */
      }

      dcr->do_unload();
      dcr->do_swapping(false/*!is_writing*/);
      dcr->do_load(false /*!is_writing*/);
      set_dcr_from_vol(dcr, vol);          /* refresh dcr with desired volume info */

      /*
       * This code ensures that the device is ready for

/*
 * Acquire device for writing. We permit multiple writers.
 *  If this is the first one, we read the label.
 *
 *  Returns: NULL if failed for any reason
 *           dcr if successful.
 *   Note, normally reserve_device_for_append() is called
 *   before this routine.
 */
DCR *acquire_device_for_append(DCR *dcr)
{
   DEVICE *dev = dcr->dev;
   JCR *jcr = dcr->jcr;
   bool ok = false;
   bool have_vol = false;

   Enter(200);
   init_device_wait_timers(dcr);

   dev->Lock_acquire();             /* only one job at a time */
   dev->Lock();
   Dmsg1(100, "acquire_append device is %s\n", dev->is_tape() ? "tape" : "disk");

   /*
    * With the reservation system, this should not happen
    */
   if (dev->can_read()) {
      Jmsg1(jcr, M_FATAL, 0, _("Want to append, but device %s is busy reading.\n"), dev->print_name());
      Dmsg1(200, "Want to append but device %s is busy reading.\n", dev->print_name());
      goto get_out;
   }

   dev->clear_unload();

   /*
    * have_vol defines whether or not mount_next_write_volume should
    *   ask the Director again about what Volume to use.
    */
   if (dev->can_append() && dcr->is_suitable_volume_mounted() &&
       !bstrcmp(dcr->VolCatInfo.VolCatStatus, "Recycle")) {
      Dmsg0(190, "device already in append.\n");
      /*
       * At this point, the correct tape is already mounted, so
       *   we do not need to do mount_next_write_volume(), unless
       *   we need to recycle the tape.
       */
       if (dev->num_writers == 0) {
          dev->VolCatInfo = dcr->VolCatInfo;   /* structure assignment */
       }
       have_vol = dcr->is_tape_position_ok();
   }

   if (!have_vol) {
      dev->rLock(true);
      block_device(dev, BST_DOING_ACQUIRE);
      dev->Unlock();
      Dmsg1(190, "jid=%u Do mount_next_write_vol\n", (uint32_t)jcr->JobId);
      if (!dcr->mount_next_write_volume()) {
         if (!job_canceled(jcr)) {
            /* Reduce "noise" -- don't print if job canceled */
            Jmsg(jcr, M_FATAL, 0, _("Could not ready device %s for append.\n"),
               dev->print_name());
            Dmsg1(200, "Could not ready device %s for append.\n",
               dev->print_name());
         }
         dev->Lock();
         unblock_device(dev);
         goto get_out;
      }
      Dmsg2(190, "Output pos=%u:%u\n", dcr->dev->file, dcr->dev->block_num);
      dev->Lock();
      unblock_device(dev);
   }

   dev->num_writers++;                /* we are now a writer */
   if (jcr->NumWriteVolumes == 0) {
      jcr->NumWriteVolumes = 1;
   }
   dev->VolCatInfo.VolCatJobs++;              /* increment number of jobs on vol */
   Dmsg4(100, "=== nwriters=%d nres=%d vcatjob=%d dev=%s\n",
         dev->num_writers, dev->num_reserved(), dev->VolCatInfo.VolCatJobs, dev->print_name());
   dcr->dir_update_volume_info(false, false); /* send Volume info to Director */
   ok = true;

get_out:
   /* Don't plugin close here, we might have multiple writers */
   dcr->clear_reserved();
   dev->Unlock();
   dev->Unlock_acquire();
   Leave(200);
   return ok ? dcr : NULL;
}

/*
 * Open the next part file.
 *  - Close the fd
 *  - Increment part number 
 *  - Reopen the device
 */
int dvd_open_next_part(DCR *dcr)
{
   DEVICE *dev = dcr->dev;

   Dmsg6(29, "Enter: == open_next_part part=%d npart=%d dev=%s vol=%s mode=%d file_addr=%d\n", 
      dev->part, dev->num_dvd_parts, dev->print_name(),
         dev->getVolCatName(), dev->openmode, dev->file_addr);
   if (!dev->is_dvd()) {
      Dmsg1(100, "Device %s is not dvd!!!!\n", dev->print_name()); 
      return -1;
   }
   
   /* When appending, do not open a new part if the current is empty */
   if (dev->can_append() && (dev->part > dev->num_dvd_parts) && 
       (dev->part_size == 0)) {
      Dmsg0(29, "open_next_part exited immediately (dev->part_size == 0).\n");
      return dev->fd();
   }

   dev->close_part(dcr);               /* close current part */
   
   /*
    * If we have a spooled part open, write it to the
    *  DVD before opening the next part.
    */
   if (dev->is_part_spooled()) {
      Dmsg2(100, "Before open next write previous. part=%d num_parts=%d\n",
         dev->part, dev->num_dvd_parts);
      if (!dvd_write_part(dcr)) {
         Dmsg0(29, "Error in dvd_write part.\n");
         return -1;
      }
   }
     
   dev->part_start += dev->part_size;
   dev->part++;
   Dmsg2(29, "Inc part=%d num_dvd_parts=%d\n", dev->part, dev->num_dvd_parts);

   /* Are we working on a part past what is written in the DVD? */
   if (dev->num_dvd_parts < dev->part) {
      POOL_MEM archive_name(PM_FNAME);
      struct stat buf;
      /* 
       * First check what is on DVD.  If our part is there, we
       *   are in trouble, so bail out.
       * NB: This is however not a problem if we are writing the first part.
       * It simply means that we are over writing an existing volume...
       */
      if (dev->num_dvd_parts > 0) {
         make_mounted_dvd_filename(dev, archive_name);   /* makes dvd name */
         Dmsg1(100, "Check if part on DVD: %s\n", archive_name.c_str());
         if (stat(archive_name.c_str(), &buf) == 0) {
            /* bad news bail out */
            dev->set_part_spooled(false);
            Mmsg1(&dev->errmsg, _("Next Volume part already exists on DVD. Cannot continue: %s\n"),
               archive_name.c_str());
            return -1;
         }
      }

#ifdef neeeded
      Dmsg2(400, "num_dvd_parts=%d part=%d\n", dev->num_dvd_parts, dev->part);
      make_spooled_dvd_filename(dev, archive_name);   /* makes spool name */
      
      /* Check if the next part exists in spool directory . */
      Dmsg1(100, "Check if part on spool: %s\n", archive_name.c_str());
      if ((stat(archive_name.c_str(), &buf) == 0) || (errno != ENOENT)) {
         Dmsg1(29, "======= Part %s is in the way, deleting it...\n", archive_name.c_str());
         /* Then try to unlink it */
         if (unlink(archive_name.c_str()) < 0) {
            berrno be;
            dev->set_part_spooled(false);
            dev->dev_errno = errno;
            Mmsg2(dev->errmsg, _("open_next_part can't unlink existing part %s, ERR=%s\n"), 
                   archive_name.c_str(), be.bstrerror());
            return -1;
         }
      }
#endif
   }

   Dmsg2(400, "Call dev->open(vol=%s, mode=%d)\n", dcr->getVolCatName(), 
         dev->openmode);

   /* Open next part.  Note, this sets part_size for part opened. */
   if (dev->open(dcr, OPEN_READ_ONLY) < 0) {
      return -1;
   } 
   dev->set_labeled();                   /* all next parts are "labeled" */
   
   return dev->fd();
}