}

    prev_job = current_job;

  } /* for(current_job) */

}

/**

   @arg head I may end up changing the head if job == head

 */

void change_job_priority(struct distrenjob *head, struct distrenjob *job, int new_priority){

  distrenjob_remove(head, job);

  job->priority = new_priority;

  struct distrenjob *current_job;

  struct distrenjob *prev_job = head;

  if(job->frameset[0].status == 0){ // if job was not yet started

    distrenjob_enqueue(head, job);

  }

  else{ // if job has already been started then place it before the jobs with the same priority

    // iterate through linked list of jobs

    for(current_job = head; current_job != NULL; current_job = current_job->next){

      if(current_job == NULL){ // if it has reached the end of the list, add job there

        current_job = job;

        break;

      }

      else if(job->priority <= current_job->priority){ // if job's priority is less than or equal to current_job's priority, insert job

        prev_job->next = job;                        // keep in mind 1 is the highest priority given to jobs, head has a

        job->next = current_job;                     // priority of zero so it will always be before other jobs

        break;

      }

      prev_job = current_job;

    }

  }

}

/**

  Frame Finder: matches your computer up with a lovely frame to render

  TODO: Major issue here, the client needs to know the frame number, AND the job number!

  Notice that this function starts by looking at the oldest job first

	TODO: Link this up with the main() function to check if there are frames available or not and provide jobnum/framenum to the client

  @return 0 success, other: error

*/

/*@TODO: change frame_finder to job_finder */

int frame_finder(struct distrenjob *head, struct distrenjob **job, struct frameset **frame)

{

  unsigned short int found;

  struct distrenjob *distrenjob_ptr;

  found = 0;

      if(!found)

        {

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

          return 1;

        }

    // the actual frame number to be rendered by the client is start_frame + your_frame

    // @TODO: refine how we want to return data from this

    //struct framejob { distrenjob_ptr; distrenjob_ptr->(&frameset[your_frame])};

      /* should the job be removed now? ANSWER: well, if a computer decides not to return their frame then we lost our data... so its not done yet. */

      fprintf(stderr, "Job %d is finished, this is probably the place to call the job-removal function\n", distrenjob_ptr->jobnum);

      /* @TODO: At this point, all slaves should be instructed to delete the source data for this job. */

  return 0;

}

/** Checks for dead, laggy, or stale slaves */

void blend_frame_watchdog(struct distrenjob *distrenjob_head)

{

  unsigned short int watchdog_forgiveness; /*< seconds to wait on a frame before re-assigning it */

  struct distrenjob *distrenjob_ptr;

  unsigned int counter;

  watchdog_forgiveness = 1; /*< hours of forgiveness before frame is re-assigned @TODO: Make this more user-configurable (maybe per-job), 3 hours is a LONG time */

  distrenjob_ptr = distrenjob_head;

  for(distrenjob_ptr = distrenjob_head; distrenjob_ptr; distrenjob_ptr = distrenjob_ptr->next)

    /* iterate through jobs */

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

      /* iterate through all frames for this job*/

      {

        if((distrenjob_ptr->frameset[counter].start_time + (watchdog_forgiveness * 3600)) < clock())

          /*

            If frame is not completed within the number of hours specified by watchdog_forgiveness

            Then change the frame status to unassigned

           */

          distrenjob_ptr->frameset[counter].status = 0;

      }

}

/**

   Finds a distrenjob struct based on the jobnum

   @arg jobnum job number to search for

   @return NULL on job doesn't exist

 */

/*

  Copyright 2009 Nathan Phillip Brink, Ethan Zonca, Matthew Orlando

  This file is a part of DistRen.

  DistRen is free software: you can redistribute it and/or modify

  it under the terms of the GNU Affero General Public License as published by

  the Free Software Foundation, either version 3 of the License, or

  (at your option) any later version.

  DistRen is distributed in the hope that it will be useful,

  but WITHOUT ANY WARRANTY; without even the implied warranty of

  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  GNU Affero General Public License for more details.

  You should have received a copy of the GNU Affero General Public License

  along with DistRen.  If not, see <http://www.gnu.org/licenses/>.

*/

#ifndef _DISTREN_DISTRENJOB_H

#define _DISTREN_DISTRENJOB_H

/**

   This file stores the distrenjob and frameset structs and prototypes for some functions to manipulate/use these.

 */

#include <time.h> /* clock_t, time_t */

typedef unsigned int jobnum_t;

/**

   Stores Blender Job Info

*/

struct distrenjob {

  struct distrenjob *next; /*< next will be NULL unless if there is another distrenjob */

  short int type; // 1:Blender, 2:something else

  char *name;

  char *submitter;

  char *email; /*< This should be looked up based on the value of submitter, not stored in this struct */

  jobnum_t jobnum;

  int priority;  // 1 is lowest, 10 is highest, 0 means the job is done

  float percent_done;

  int completed_frames; // number of completed frames for stats/etc

  int assigned_frames; // number of assigned frames (that are not yet completed) for stats/etc

  int total_frames; // how many frames are in the animation for stats/etc (unassigned frames)

  int watchdog_forgiveness; // how many hours till the frame is re-assigned (if client computer crashes etc);

  time_t avg_render_time; // average seconds it took to render a frame

  time_t time_remaining; /*< estimated seconds remaining till render is complete (up to 49, 710 days) */

  char *output_format; /*< currently is the file extention of the request output format. @todo make this mime-type based/not a string */

  struct frameset *frameset;

};

/**

   Frameset Structure

*/

struct frameset {

  int num; /*< frame number to render */

  char slave_name; /*< user that frame is assigned to */

  int status; /*< status of frame, 0= unassigned, 1= taken, 2= done */

  clock_t start_time; /*< time the frame was started */

  int time_to_render; /*< the total seconds it took to render the frame */

}; /* Frameset array is generated by status_report_generator() */

/*

related functions

*/

/**

   @param distrenjob the address where we will store the pointer of a malloc()ed

   distrenjob struct.

   @param pathtoxml filename/pathname of the xml file to be read into a distrenjob struct

 */

int xml2distrenjob(struct distrenjob **distrenjob, char *pathtoxml);

/**

   support function for xml2distrenjob() to help cleaning up a

   struct distrenjob when it is incompletely initialized.

   Also acts as a general-purpose struct distrenjob free()er ;-)

 */

void distrenjob_free(struct distrenjob **distrenjob);