C++ DEVICE::clear_unload方法代码示例

//.........这里部分代码省略.........
      unlock_reservations();

      if (status == 1) { /* found new device to use */
         /*
          * Switching devices, so acquire lock on new device,
          *   then release the old one.
          */
         dcr->dev->Lock_read_acquire();      /* lock new one */
         dev->Unlock_read_acquire();         /* release old one */
         dev = dcr->dev;                     /* get new device pointer */
         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);

/*
 * 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;
}