C++ DEVICE::open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.........

   /* 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
       * reading. If it is a file, it opens it.
       * If it is a tape, it checks the volume name
       */
      Dmsg1(rdbglvl, "stored: open vol=%s\n", dcr->VolumeName);
      if (!dev->open(dcr, OPEN_READ_ONLY)) {
         if (!dev->poll) {
            Jmsg3(jcr, M_WARNING, 0, _("Read open device %s Volume \"%s\" failed: ERR=%s\n"),
                  dev->print_name(), dcr->VolumeName, dev->bstrerror());
         }
         goto default_path;
      }
      Dmsg1(rdbglvl, "opened dev %s OK\n", dev->print_name());

      /* Read Volume Label */
      Dmsg0(rdbglvl, "calling read-vol-label\n");
      vol_label_status = read_dev_volume_label(dcr);
      switch (vol_label_status) {
      case VOL_OK:
         Dmsg0(rdbglvl, "Got correct volume.\n");
         ok = true;
         dev->VolCatInfo = dcr->VolCatInfo;     /* structure assignment */
         break;                    /* got it */
      case VOL_IO_ERROR:
         Dmsg0(rdbglvl, "IO Error\n");
         /*
          * Send error message generated by read_dev_volume_label()
          *  only we really had a tape mounted. This supresses superfluous
          *  error messages when nothing is mounted.
          */
         if (tape_previously_mounted) {
            Jmsg(jcr, M_WARNING, 0, "Read acquire: %s", jcr->errmsg);
         }
         goto default_path;
      case VOL_NAME_ERROR:
         Dmsg3(rdbglvl, "Vol name=%s want=%s drv=%s.\n", dev->VolHdr.VolumeName,
               dcr->VolumeName, dev->print_name());

/*
 * 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();
}

/*
 * Write a Volume Label
 *  !!! Note, this is ONLY used for writing
 *            a fresh volume label.  Any data
 *            after the label will be destroyed,
 *            in fact, we write the label 5 times !!!!
 *
 *  This routine should be used only when labeling a blank tape.
 */
bool write_new_volume_label_to_dev(DCR *dcr, const char *VolName,
                                   const char *PoolName, bool relabel)
{
   JCR *jcr = dcr->jcr;
   DEVICE *dev = dcr->dev;
   DEV_BLOCK *block = dcr->block;

   Dmsg0(150, "write_volume_label()\n");
   if (*VolName == 0) {
      Pmsg0(0, "=== ERROR: write_new_volume_label_to_dev called with NULL VolName\n");
      goto bail_out;
   }

   if (relabel) {
      volume_unused(dcr);             /* mark current volume unused */
      /* Truncate device */
      if (!dev->truncate(dcr)) {
         goto bail_out;
      }
      if (!dev->is_tape()) {
         dev->close(dcr);             /* make sure file closed for rename */
      }
   }

   /* Set the new filename for open, ... */
   dev->setVolCatName(VolName);
   dcr->setVolCatName(VolName);
   Dmsg1(150, "New VolName=%s\n", VolName);
   if (!dev->open(dcr, OPEN_READ_WRITE)) {
      /* If device is not tape, attempt to create it */
      if (dev->is_tape() || !dev->open(dcr, CREATE_READ_WRITE)) {
         Jmsg3(jcr, M_WARNING, 0, _("Open device %s Volume \"%s\" failed: ERR=%s\n"),
               dev->print_name(), dcr->VolumeName, dev->bstrerror());
         goto bail_out;
      }
   }
   Dmsg1(150, "Label type=%d\n", dev->label_type);

   /*
    * Let any stored plugin know that we are about to write a new label to the volume.
    */
   if (generate_plugin_event(jcr, bsdEventLabelWrite, dcr) != bRC_OK) {
      Dmsg0(200, "Error from bsdEventLabelWrite plugin event.\n");
      goto bail_out;
   }

   for ( ;; ) {
      empty_block(block);
      if (!dev->rewind(dcr)) {
         Dmsg2(130, "Bad status on %s from rewind: ERR=%s\n", dev->print_name(), dev->print_errmsg());
         if (!forge_on) {
            goto bail_out;
         }
      }

      /* Temporarily mark in append state to enable writing */
      dev->set_append();

      /* Create PRE_LABEL */
      create_volume_label(dev, VolName, PoolName);

      /*
       * If we have already detected an ANSI label, re-read it
       *   to skip past it. Otherwise, we write a new one if
       *   so requested.
       */
      if (dev->label_type != B_BAREOS_LABEL) {
         if (read_ansi_ibm_label(dcr) != VOL_OK) {
            dev->rewind(dcr);
            goto bail_out;
         }
      } else if (!write_ansi_ibm_labels(dcr, ANSI_VOL_LABEL, VolName)) {
         goto bail_out;
      }

      create_volume_label_record(dcr, dev, dcr->rec);
      dcr->rec->Stream = 0;
      dcr->rec->maskedStream = 0;

      if (!write_record_to_block(dcr, dcr->rec)) {
         Dmsg2(130, "Bad Label write on %s: ERR=%s\n", dev->print_name(), dev->print_errmsg());
         goto bail_out;
      } else {
         Dmsg2(130, "Wrote label of %d bytes to %s\n", dcr->rec->data_len, dev->print_name());
      }

      Dmsg0(130, "Call write_block_to_dev()\n");
      if (!dcr->write_block_to_dev()) {
         Dmsg2(130, "Bad Label write on %s: ERR=%s\n", dev->print_name(), dev->print_errmsg());
         goto bail_out;
      }
//.........这里部分代码省略.........