func makeConfig() empa.Config {
var c empa.Config
// Number of real available CPUs
c.NCPUs = runtime.NumCPU()
// Number of processes to start
c.NSubprocs = c.NCPUs
// Buffer input and output to reduce goroutines switches
c.InCount = 1024
c.OutCount = 1024
c.InEOL = empa.EOL('\n')
c.OutEOL = empa.EOL('\n')
return c
}
func main() {
var (
dir string
file string
zero bool
)
conf := makeConfig()
flag.StringVar(&dir, "dir", "", "Directory `DIR` to scan as input source")
flag.StringVar(&file, "file", "", "File `FILE` to read as input source")
flag.IntVar(&conf.ProcID, "w", 0, "Worker number `N` of this process")
flag.IntVar(&conf.NProcs, "wg", 0, "Total number `N` of workers that are being run")
flag.IntVar(&conf.NSubprocs, "p", conf.NSubprocs, "Number of processes `N` to run in parallel")
flag.BoolVar(&zero, "0", false, "Read input and write to subprocesses lines delimited by null character instead of newline")
flag.Parse()
args := flag.Args()
if len(args) < 1 {
flag.Usage()
os.Exit(1)
}
if zero {
conf.InEOL = empa.EOL('\x00')
}
r := empa.NewRunner(conf)
r.Run(os.Stderr, os.Stdout)
// Create and start NSubprocs subprocesses. Failure to startup is fatal.
for i := 0; i < conf.NSubprocs; i++ {
cmd := empa.NewCmd(args[0], args[1:]...)
if err := r.Start(i, cmd); err != nil {
log.Fatal("ep: ", err)
}
}
// Three modes of operation:
// 1. Input generated by walking the filesystem tree
// 2. Input generated by reading a physical file
// 3. Input generated by reading stdin.
switch true {
case dir != "":
go walkDir(r, dir)
case file != "":
f, err := os.Open(file)
if err != nil {
log.Fatal("ep: ", err)
}
go feedReader(r, f, conf.InEOL)
default:
go feedReader(r, os.Stdin, conf.InEOL)
}
r.Wait()
}
func main() {
var (
algo string
h hash.Hash
null bool
eol empa.EOL = '\n'
)
flag.StringVar(&algo, "t", "sha1", "Type `T` of hash function to use; available are: md5, sha1, sha256, sha512")
flag.BoolVar(&null, "0", false, "Read null separated lines")
flag.Parse()
switch strings.ToLower(algo) {
case "md5":
h = md5.New()
case "sha1":
h = sha1.New()
case "sha256":
h = sha256.New()
case "sha512":
h = sha512.New()
default:
log.Fatal("Invalid hash type specified; available are: md5, sha1, sha256, sha512")
}
if null {
eol = empa.EOL('\x00')
}
sc := bufio.NewScanner(os.Stdin)
sc.Split(eol.ScanLines)
for sc.Scan() {
fname := sc.Text()
if err := proc(h, fname); err != nil {
fmt.Fprintf(os.Stderr, "%s: %s\n", fname, err)
}
}
if err := sc.Err(); err != nil {
log.Fatal("epsum: ", err)
}
}