Synnefo

# -*- coding: utf-8 -

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from pithos.workers import glue

import pickle

from svipc import sem_init, sem_take, sem_give

def find_hole(WORKERS, FOLLOW_WORKERS):

        old_key = []

        old_age =  []

        for key in FOLLOW_WORKERS:

                if key not in WORKERS.keys():

                        old_age.append(FOLLOW_WORKERS[key] )

                        old_key.append( key )

                        break

        if len(old_age) and len(old_key):

                for key in old_key:

                        del FOLLOW_WORKERS[key]

                return old_age

        return old_age

def follow_workers(pid, wid, WORKERS):

        hole = None

        try:

                fd = open('/dev/shm/wid','rb')

                f = pickle.load(fd)

                hole = find_hole(WORKERS, f)

                if len(hole) > 0:

                    k = {pid: int(hole[0])}

                else:

                    k = {pid: wid}

                f.update(k)

                fd.close()

                fd = open('/dev/shm/wid','wb')

                pickle.dump(f, fd)

                fd.close()

        except:

                fd = open('/dev/shm/wid','wb')

                pickle.dump({pid:wid}, fd)

                fd.close()

        return hole

def allocate_wid(pid, wid, WORKERS):

        d = {pid: wid}

        hole = None

        if sem_init(88,nums=1) == 0:

                hole = follow_workers(pid, wid, WORKERS)

                sem_give(88,0)

        else:

                sem_take(88,0)

                hole = follow_workers(pid, wid, WORKERS)

                sem_give(88,0)

        return hole

def post_fork(server,worker):

        wid = allocate_wid(worker.pid,worker.worker_id, server.WORKERS)

        if wid:

                glue.WorkerGlue.setmap(worker.pid,wid[0])

        else:

                glue.WorkerGlue.setmap(worker.pid,worker.worker_id)