func (depot *Depot) BuildDat(dat *types.Dat, outpath string, numSubworkers int, deduper dedup.Deduper) (bool, error) { datPath := filepath.Join(outpath, dat.Name) err := os.Mkdir(datPath, 0777) if err != nil { return false, err } fixDat := new(types.Dat) fixDat.FixDat = true fixDat.Name = "fix_" + dat.Name fixDat.Description = dat.Description fixDat.Path = dat.Path fixDat.UnzipGames = dat.UnzipGames wc := make(chan *types.Game) erc := make(chan error) closeC := make(chan bool) mutex := new(sync.Mutex) for i := 0; i < numSubworkers; i++ { gb := new(gameBuilder) gb.depot = depot gb.wc = wc gb.erc = erc gb.mutex = mutex gb.datPath = datPath gb.fixDat = fixDat gb.index = i gb.deduper = deduper gb.closeC = closeC go gb.work() } var minionErr error endLoop: for _, game := range dat.Games { select { case wc <- game: case err := <-erc: minionErr = err break endLoop } } close(wc) finishedSubworkers := 0 endLoop2: for { glog.V(4).Infof("builder master: finished so far %d", finishedSubworkers) select { case <-closeC: glog.V(4).Infof("builder master: finished another subworker") finishedSubworkers++ if finishedSubworkers == numSubworkers { break endLoop2 } case err := <-erc: glog.V(4).Infof("builder master: minion error") minionErr = err } } if minionErr != nil { return false, minionErr } if len(fixDat.Games) > 0 { fixDatPath := filepath.Join(outpath, fixPrefix+dat.Name+datSuffix) fixFile, err := os.Create(fixDatPath) if err != nil { return false, err } defer fixFile.Close() fixWriter := bufio.NewWriter(fixFile) defer fixWriter.Flush() err = types.ComposeCompliantDat(fixDat, fixWriter) if err != nil { return false, err } } return len(fixDat.Games) > 0, nil }