/*
   Bacula(R) - The Network Backup Solution

   Copyright (C) 2000-2016 Kern Sibbald

   The original author of Bacula is Kern Sibbald, with contributions
   from many others, a complete list can be found in the file AUTHORS.

   You may use this file and others of this release according to the
   license defined in the LICENSE file, which includes the Affero General
   Public License, v3.0 ("AGPLv3") and some additional permissions and
   terms pursuant to its AGPLv3 Section 7.

   This notice must be preserved when any source code is 
   conveyed and/or propagated.

   Bacula(R) is a registered trademark of Kern Sibbald.
*/
/*
 *  Subroutines to handle waiting for operator intervention
 *   or waiting for a Device to be released
 *
 *  Code for wait_for_sysop() pulled from askdir.c
 *
 *   Kern Sibbald, March 2005
 *
 */


#include "bacula.h"                   /* pull in global headers */
#include "stored.h"                   /* pull in Storage Deamon headers */

const int dbglvl = 400;

/*
 * Wait for SysOp to mount a tape on a specific device
 *
 *   Returns: W_ERROR, W_TIMEOUT, W_POLL, W_MOUNT, or W_WAKE
 */
int wait_for_sysop(DCR *dcr)
{
   struct timeval tv;
   struct timezone tz;
   struct timespec timeout;
   time_t last_heartbeat = 0;
   time_t first_start = time(NULL);
   int stat = 0;
   int add_wait;
   bool unmounted;
   DEVICE *dev = dcr->dev;
   JCR *jcr = dcr->jcr;

   dev->Lock();
   Dmsg1(dbglvl, "Enter blocked=%s\n", dev->print_blocked());

   /*
    * Since we want to mount a tape, make sure current one is
    *  not marked as using this drive.
    */
   volume_unused(dcr);

   unmounted = dev->is_device_unmounted();
   dev->poll = false;
   /*
    * Wait requested time (dev->rem_wait_sec).  However, we also wake up every
    *    HB_TIME seconds and send a heartbeat to the FD and the Director
    *    to keep stateful firewalls from closing them down while waiting
    *    for the operator.
    */
   add_wait = dev->rem_wait_sec;
   if (me->heartbeat_interval && add_wait > me->heartbeat_interval) {
      add_wait = me->heartbeat_interval;
   }
   /* If the user did not unmount the tape and we are polling, ensure
    *  that we poll at the correct interval.
    */
   if (!unmounted && dev->vol_poll_interval && add_wait > dev->vol_poll_interval) {
      add_wait = dev->vol_poll_interval;
   }

   if (!unmounted) {
      Dmsg1(dbglvl, "blocked=%s\n", dev->print_blocked());
      dev->dev_prev_blocked = dev->blocked();
      dev->set_blocked(BST_WAITING_FOR_SYSOP); /* indicate waiting for mount */
   }

   for ( ; !job_canceled(jcr); ) {
      time_t now, start, total_waited;

      gettimeofday(&tv, &tz);
      timeout.tv_nsec = tv.tv_usec * 1000;
      timeout.tv_sec = tv.tv_sec + add_wait;

      Dmsg4(dbglvl, "I'm going to sleep on device %s. HB=%d rem_wait=%d add_wait=%d\n",
         dev->print_name(), (int)me->heartbeat_interval, dev->rem_wait_sec, add_wait);
      start = time(NULL);

      /* Wait required time */
      stat = dev->next_vol_timedwait(&timeout);

      Dmsg2(dbglvl, "Wokeup from sleep on device stat=%d blocked=%s\n", stat,
         dev->print_blocked());
      now = time(NULL);
      total_waited = now - first_start;
      dev->rem_wait_sec -= (now - start);

      /* Note, this always triggers the first time. We want that. */
      if (me->heartbeat_interval) {
         if (now - last_heartbeat >= me->heartbeat_interval) {
            /* send heartbeats */
            if (jcr->file_bsock) {
               jcr->file_bsock->signal(BNET_HEARTBEAT);
               Dmsg0(dbglvl, "Send heartbeat to FD.\n");
            }
            if (jcr->dir_bsock) {
               jcr->dir_bsock->signal(BNET_HEARTBEAT);
            }
            last_heartbeat = now;
         }
      }

      if (stat == EINVAL) {
         berrno be;
         Jmsg1(jcr, M_FATAL, 0, _("pthread timedwait error. ERR=%s\n"), be.bstrerror(stat));
         stat = W_ERROR;               /* error */
         break;
      }

      /*
       * Continue waiting if operator is labeling volumes
       */
      if (dev->blocked() == BST_WRITING_LABEL) {
         continue;
      }

      if (dev->rem_wait_sec <= 0) {  /* on exceeding wait time return */
         Dmsg0(dbglvl, "Exceed wait time.\n");
         stat = W_TIMEOUT;
         break;
      }

      /*
       * Check if user unmounted the device while we were waiting
       */
      unmounted = dev->is_device_unmounted();

      if (!unmounted && dev->vol_poll_interval &&
          (total_waited >= dev->vol_poll_interval)) {
         Dmsg1(dbglvl, "poll return in wait blocked=%s\n", dev->print_blocked());
         dev->poll = true;            /* returning a poll event */
         stat = W_POLL;
         break;
      }
      /*
       * Check if user mounted the device while we were waiting
       */
      if (dev->blocked() == BST_MOUNT) {   /* mount request ? */
         Dmsg0(dbglvl, "Mounted return.\n");
         stat = W_MOUNT;
         break;
      }

      /*
       * If we did not timeout, then some event happened, so
       *   return to check if state changed.
       */
      if (stat != ETIMEDOUT) {
         berrno be;
         Dmsg2(dbglvl, "Wake return. stat=%d. ERR=%s\n", stat, be.bstrerror(stat));
         stat = W_WAKE;          /* someone woke us */
         break;
      }

      /*
       * At this point, we know we woke up because of a timeout,
       *   that was due to a heartbeat, because any other reason would
       *   have caused us to return, so update the wait counters and continue.
       */
      add_wait = dev->rem_wait_sec;
      if (me->heartbeat_interval && add_wait > me->heartbeat_interval) {
         add_wait = me->heartbeat_interval;
      }
      /* If the user did not unmount the tape and we are polling, ensure
       *  that we poll at the correct interval.
       */
      if (!unmounted && dev->vol_poll_interval &&
           add_wait > dev->vol_poll_interval - total_waited) {
         add_wait = dev->vol_poll_interval - total_waited;
      }
      if (add_wait < 0) {
         add_wait = 0;
      }
   }

   if (!unmounted) {
      dev->set_blocked(dev->dev_prev_blocked);    /* restore entry state */
      Dmsg1(dbglvl, "set %s\n", dev->print_blocked());
   }
   Dmsg1(dbglvl, "Exit blocked=%s\n", dev->print_blocked());
   dev->Unlock();
   return stat;
}


/*
 * Wait for any device to be released, then we return, so
 *  higher level code can rescan possible devices.  Since there
 *  could be a job waiting for a drive to free up, we wait a maximum
 *  of 1 minute then retry just in case a broadcast was lost, and
 *  we return to rescan the devices.
 *
 * Returns: true  if a device has changed state
 *          false if the total wait time has expired.
 */
bool wait_for_any_device(JCR *jcr, int &retries)
{
   struct timeval tv;
   struct timezone tz;
   struct timespec timeout;
   int stat = 0;
   bool ok = true;
   const int max_wait_time = 1 * 60;       /* wait 1 minute */
   char ed1[50];

   Dmsg0(dbglvl, "Enter wait_for_any_device\n");
   P(device_release_mutex);

   if (++retries % 5 == 0) {
      /* Print message every 5 minutes */
      Jmsg(jcr, M_MOUNT, 0, _("JobId=%s, Job %s waiting to reserve a device.\n"),
         edit_uint64(jcr->JobId, ed1), jcr->Job);
   }

   gettimeofday(&tv, &tz);
   timeout.tv_nsec = tv.tv_usec * 1000;
   timeout.tv_sec = tv.tv_sec + max_wait_time;

   Dmsg0(dbglvl, "Going to wait for a device.\n");

   /* Wait required time */
   stat = pthread_cond_timedwait(&wait_device_release, &device_release_mutex, &timeout);
   Dmsg1(dbglvl, "Wokeup from sleep on device stat=%d\n", stat);

   V(device_release_mutex);
   Dmsg1(dbglvl, "Return from wait_device ok=%d\n", ok);
   return ok;
}

/*
 * Wait for a specific device to be released
 *  We wait a maximum of 1 minute then
 *  retry just in case a broadcast was lost.
 *
 * Returns: true  if the device has changed state
 *          false if the total wait time has expired.
 */
bool wait_for_device(DCR *dcr, int &retries)
{
   struct timeval tv;
   struct timezone tz;
   struct timespec timeout;
   JCR *jcr = dcr->jcr;
   DEVICE *dev = dcr->dev;
   int stat = 0;
   bool ok = true;
   const int max_wait_time = 1 * 60;       /* wait 1 minute */
   char ed1[50];

   Dmsg3(40, "Enter wait_for_device. busy=%d dcrvol=%s devvol=%s\n",
      dev->is_busy(), dcr->VolumeName, dev->getVolCatName());

   P(device_release_mutex);

   if (++retries % 5 == 0) {
      /* Print message every 5 minutes */
      Jmsg(jcr, M_MOUNT, 0, _("JobId=%s, Job %s waiting device %s.\n"),
         edit_uint64(jcr->JobId, ed1), jcr->Job, dcr->dev->print_name());
   }

   gettimeofday(&tv, &tz);
   timeout.tv_nsec = tv.tv_usec * 1000;
   timeout.tv_sec = tv.tv_sec + max_wait_time;

   Dmsg0(dbglvl, "Going to wait for a device.\n");

   /* Wait required time */
   stat = pthread_cond_timedwait(&wait_device_release, &device_release_mutex, &timeout);
   Dmsg1(dbglvl, "Wokeup from sleep on device stat=%d\n", stat);

   V(device_release_mutex);
   Dmsg1(dbglvl, "Return from wait_device ok=%d\n", ok);
   return ok;
}


#ifdef xxx
/*
 * The jcr timers are used for waiting on any device *
 * Returns: true if time doubled
 *          false if max time expired
 */
static bool double_jcr_wait_time(JCR *jcr)
{
   jcr->wait_sec *= 2;               /* double wait time */
   if (jcr->wait_sec > jcr->max_wait) {   /* but not longer than maxtime */
      jcr->wait_sec = jcr->max_wait;
   }
   jcr->num_wait++;
   jcr->rem_wait_sec = jcr->wait_sec;
   if (jcr->num_wait >= jcr->max_num_wait) {
      return false;
   }
   return true;
}
#endif
