package yggdrasil

// These are misc. utility functions that didn't really fit anywhere else

import "fmt"
import "runtime"
//import "sync"

func Util_testAddrIDMask() {
  for idx := 0 ; idx < 16 ; idx++ {
    var orig NodeID
    orig[8] = 42
    for bidx := 0 ; bidx < idx ; bidx++ {
      orig[bidx/8] |= (0x80 >> uint8(bidx % 8))
    }
    addr := address_addrForNodeID(&orig)
    nid, mask := addr.getNodeIDandMask()
    for b := 0 ; b < len(mask) ; b++ {
      nid[b] &= mask[b]
      orig[b] &= mask[b]
    }
    if *nid != orig {
      fmt.Println(orig)
      fmt.Println(*addr)
      fmt.Println(*nid)
      fmt.Println(*mask)
      panic(idx)
    }
  }
}

func util_yield() {
  runtime.Gosched()
}

func util_lockthread() {
  runtime.LockOSThread()
}

func util_unlockthread() {
  runtime.UnlockOSThread()
}

/*
var byteStore sync.Pool = sync.Pool{
  New: func () interface{} { return []byte(nil) },
}

func util_getBytes() []byte {
  return byteStore.Get().([]byte)[:0]
}

func util_putBytes(bs []byte) {
  byteStore.Put(bs) // FIXME? The cast to interface{} allocates...
}
*/

var byteStore chan []byte

func util_initByteStore() {
  if byteStore == nil {
    byteStore = make(chan []byte, 32)
  }
}

func util_getBytes() []byte {
  select {
    case bs := <-byteStore: return bs[:0]
    default: return nil
  }
}

func util_putBytes(bs []byte) {
  select {
    case byteStore<-bs:
    default:
  }
}