xmlcleanup();

  /** free() paths */

  free(general_info.files.geninfo);

  mysqlDisconnect(conn);

  return 0;

}

/* ********************** Functions ************************* */

/** Dumps all data in RAM to an xml file (such as current jobs, etc) which is parsed by start_data. Remember to invoke this before shutting down! @TODO: Fill this stub*/

int xml_dump()

{

  return 0;

}

/**

   Performs command stored in a client's request. @TODO: Fill stub

*/

int distrend_do()

{

  return 0;

}

/** 

    Fill variables at startup from XML dumps or defaults

 */

int start_data(struct general_info *general_info)

{

  struct stat buffer;

  /**

     defaults

   */

  memset(&general_info->head, '\0', sizeof(struct distrenjob));

  general_info->head.priority = 0;

  general_info->jobs_in_queue = 0;

  general_info->free_clients = 0;

      fprintf(stderr, "Restoring queue...\n");

      if(createQueueFromXML(general_info))

        fprintf(stderr, "FAILURE\n");

      fprintf(stderr, "done\n");

    }

  return 0;

}

/** Finish-Setter: Sets a frame to the "completed" status.*/

void finish_frame(struct general_info *geninfo, struct distrenjob *distrenjob, int frame)

{

  distrenjob->frameset[frame].status = FRAMESETSTATUS_DONE;

  distrenjob->total_render_time = distrenjob->total_render_time + (clock() - distrenjob->frameset[frame].start_time);

  distrenjob->completed_frames ++;

  distrenjob->assigned_frames --;

  geninfo->total_frames_rendered ++; /*< Increase total frames var for stats */

  update_general_info(geninfo);

  updateJobStatsXML(distrenjob);

}

/**

   checks to see if a job is actually done.

   - scans the folder of the job to make sure all output files are present

*/

int mortition(struct general_info *geninfo, struct distrenjob *job)

{

  short int isJobDone;

  int counter;

  char *path_and_number;

  struct stat buffer;

  isJobDone = 1;

  for(counter = 0; counter < job->total_frames; counter++)

    {

      _distren_asprintf(&path_and_number, "%s/stor/job%d/out/%d.%s",

                        geninfo->config->datadir,

    job->prev_frame_index = -1;

  update_general_info(geninfo);

  return 0;

}

/**

   scans the frames of a job to initialize a job after server

   @return 0 if the job is completely done and there are no missing frames,

           1 if missing frames are found.

*/

int restoreJobState(struct distrenjob *job)

{

  short int isJobDone;

  int counter;

  char *path_and_number;

  struct stat buffer;

  isJobDone = 1;

  for(counter = 0; counter < job->total_frames; counter++)

    {

      _distren_asprintf(&path_and_number, "stor/job%d/out/%d.%s", job->jobnum, job->frameset[counter].num, job->output_format); /*< @TODO this path is used in multiple places, construct/build/determine it in a central function */

      if(stat(path_and_number, &buffer) == 0)

      free(path_and_number);

    }

  return !isJobDone;

}

/**

   creates a structure from starting data, then calls another

   function to actually add that struct to the queue.

   Passed strings must be free()d by the caller.

*/

int prepare_distrenjob(struct general_info *geninfo, int type, char *name, char *submitter, int priority, int start_frame, int end_frame, int width, int height)

{

  int counter;

  int counter2;

  int tmp;

  char *serialfile;

  struct distrenjob *distrenjob;

  tmp = distrenjob_new(&distrenjob);

  if(tmp)

    return 1;

  update_general_info(geninfo);

  fprintf(stderr, "prepare_distrenjob(): attempting updateJobStatsXML()\n");

  updateJobStatsXML(distrenjob);

  return 0;

}

/**

   Adds the job to the queue based on its priority.

   Updates geninfo->jobs_in_queue.

*/

int distrenjob_enqueue(struct general_info *geninfo, struct distrenjob *job)

{

  struct distrenjob *prev_job;

  struct distrenjob *current_job;

  struct distrenjob *head;

  head = &geninfo->head;

  prev_job = head;

  /**

     iterate through linked jobs

  */

  /**

     if it has reached the end of the list, add job there

  */

  prev_job->next = job;

  fprintf(stderr, "added job at end of queue\n");

  geninfo->jobs_in_queue ++;

  return 0;

}

/** Changes the priority of an existing (and maybe running) job. @arg head I may end up changing the head if job == head */

int change_job_priority(struct general_info *geninfo, struct distrenjob *job, int new_priority){

  struct distrenjob *current_job;

  struct distrenjob *prev_job;

  char *serialname;

  distrenjob_remove(geninfo, job);

  job->priority = new_priority;

  prev_job = &geninfo->head;

  if(job->frameset[0].status == FRAMESETSTATUS_UNASSIGNED)

    /**

       if job was not yet started

  distrenjob_serialize(job, serialname);

  free(serialname);

  return 0;

}

/**

  Frame Finder: matches your computer up with a lovely frame to render, starts looking at oldest job first

  @TODO: We must return both jobnum and framenum

  @TODO: Add calls in main()

  @return 0 success, other: error

*/

int find_jobframe(struct general_info *geninfo, struct distrenjob **job, struct frameset **frame)

{

  if(geninfo->hibernate)

    return 1;

  unsigned int frame_counter;

  unsigned short int found;

  struct distrenjob *distrenjob_ptr;

  found = 0;

  /* iterate through jobs from first to last */

  for(distrenjob_ptr = geninfo->head.next; distrenjob_ptr && !distrenjob_ptr->hibernate; distrenjob_ptr = distrenjob_ptr->next)

  {

    {

      fprintf(stderr, "No more jobs to render\n");

      sleep(1); /*< @todo eliminate the need for this line*/

      return 1;

    }

  *job = distrenjob_ptr;

  *frame = &distrenjob_ptr->frameset[frame_counter];

  return 0;

}

int find_jobframe_from_job(struct distrenjob *distrenjob_ptr, struct distrenjob **job, struct frameset **frame)

{

  unsigned int frame_counter;

  unsigned short int found;

  found = 0;

  for(frame_counter = (distrenjob_ptr->prev_frame_index + 1); frame_counter < distrenjob_ptr->total_frames; frame_counter ++)

  {

    if(distrenjob_ptr->frameset[frame_counter].status == FRAMESETSTATUS_UNASSIGNED) // jobframe found

      {

        found = 1;

                distrenjob_ptr->frameset[frame_counter].status = FRAMESETSTATUS_ASSIGNED;

      fprintf(stderr, "No more frames in this job number %d", distrenjob_ptr->jobnum);

      distrenjob_ptr->prev_frame_index = frame_counter;

      return 1;

    }

  *job = distrenjob_ptr;

  *frame = &distrenjob_ptr->frameset[frame_counter];

  return 0;

}

// find a frame to render when the job that the last frame was for no longer exists

int find_jobframe_new(struct general_info *geninfo, int rend_pwr, struct distrenjob **job, struct frameset **frame)

{

  if(geninfo->hibernate)

    return 1;

  float power_difference;

  float greatest_power_difference;

  unsigned short int found;

  struct distrenjob *job_to_render;

  struct distrenjob *distrenjob_ptr;

    {

      fprintf(stderr, "No more jobs to render\n");

      return 1;

    }

  find_jobframe_from_job(job_to_render, job, frame);

  job_to_render->assigned_render_power = job_to_render->assigned_render_power + rend_pwr;

  return 0;

}

// gets a frame to render from the same job that the previously rendered frame was from

int find_jobframe_again(struct general_info *geninfo, int jobnum, int rend_pwr, struct distrenjob **job, struct frameset **frame)

{

  if(geninfo->hibernate)

    return 1;

  short int found;

  struct distrenjob *distrenjob_ptr;

  distrenjob_ptr = distrenjob_get(&geninfo->head, jobnum);

  // if the job was not found or there are no frames left in the job...

  if(!distrenjob_ptr || distrenjob_ptr->prev_frame_index >= (distrenjob_ptr->total_frames - 1))

            distrenjob_ptr->assigned_frames--;

        }

    updateJobStatsXML(distrenjob_ptr);

  }

}

/**

   Finds a distrenjob struct based on the jobnum

   @arg jobnum job number to search for

   @return NULL on job doesn't exist

 */

struct distrenjob *distrenjob_get(struct distrenjob *head, jobnum_t jobnum)

{

  struct distrenjob *distrenjob_ptr;

  /*

    The conditions of the for loop will leave distrenjob_ptr at NULL if the end of the list is reached. It will leave it pointing to the correct job if it is found.

   */

  for(distrenjob_ptr = head;

      distrenjob_ptr

        && distrenjob_ptr->jobnum != jobnum;

      distrenjob_ptr = distrenjob_ptr->next);

  return distrenjob_ptr;

}

/**

   Removes a distrenjob from the distrenjob linked list. It does not free the

   distrenjob, however. You should do that with distrenjob_free() from distrenjob.h.

   Updates geninfo->jobs_in_queue.

   @arg head pointer to the head of the linkedlist of distrenjobs

 */

void distrenjob_remove(struct general_info *geninfo, struct distrenjob *bj)

{

  struct distrenjob *previous_distrenjob;

  for(previous_distrenjob = &geninfo->head;

      previous_distrenjob

        && previous_distrenjob->next != bj; /*< stop on the distrenjob that comes before bj */

      previous_distrenjob = previous_distrenjob->next)

    ;

  /*

    This removes references to bj from the linked list. I.E., we now skip bj when iterating through the list

  general_info->total_render_power = 0;

  general_info->total_priority_pieces = 0;

  xmlFreeDoc(doc);

  return 0;

}

/**

   determines path to the distenjob XML file and

   calls distrenjob_unserialize()

 */

int restore_distrenjob(struct general_info *geninfo, struct distrenjob **distrenjob, jobnum_t jobnum)

{

  int tmp;

  char *file_name;

  tmp = job_getserialfilename(&file_name, geninfo, jobnum, 0);

  if(tmp)

    return tmp;

  tmp = distrenjob_unserialize(distrenjob, file_name);

  if(tmp)

    fprintf(stderr, "failed to load job %d from ``%s''\n",

            jobnum, file_name);

  free(file_name);

  return tmp;

}

int updateJobStatsXML(struct distrenjob *job)

{

          xmlTextWriterPtr writer;

          char *tmp;

          _distren_asprintf(&tmp, "stor/job%d/stats.xml", job->jobnum);

          /**

             create xml document at the location tmp with no compression

          */

          writer = xmlNewTextWriterFilename(tmp, 0);

          free(tmp);

                   completed).

          */

          xmlFreeTextWriter(writer);

          return 1;

}

/**

   updates job_list.xml which lists all the jobs in the queue

   @return 0 means success

*/

int update_xml_joblist(struct general_info *geninfo)

{

  struct distrenjob *job;

  xmlTextWriterPtr writer;

  char *tmp;

  int counter;

  /**

     update timestamp

  */

  geninfo->timestamp ++;

  if(geninfo->timestamp > 65530)

  /**

     free writer and save xml file to disk

  */

  xmlFreeTextWriter(writer);

  return 0;

}

/**

 returns 0 if completed successfully

 this reads a list of jobs in the queue before DistRen was shut down

 and then adds the jobs to the queue, as if it were never shut down

*/

int createQueueFromXML(struct general_info *geninfo)

{

  int tmp;

  xmlDocPtr doc;

  xmlNodePtr cur;

  char *xmllist_path;

  /**

     load xml document

  */

  tmp = reCreateQueueFromXML(geninfo, doc, cur);

  xmlFreeDoc(doc);

  return tmp;

}

/**

   inserts jobs at front of queue, starting

   with the last job in the job_list xml file

   to preserve the order of the queue

*/

int reCreateQueueFromXML(struct general_info *geninfo, xmlDocPtr doc, xmlNodePtr current)

{

  struct distrenjob *holder; // holds the job that "was" after head, so that the new struct can be inserted after head

  struct distrenjob *job; // job to be added

  xmlChar *tmp;

  jobnum_t job_num;

  if(current == NULL) // base case, if element doesn't exist then don't do anything

    return 0;

  /**

     recursively call itself so that the next job in

     the queue is added to the front before the current one