buf    bytes.Buffer
	mu     sync.RWMutex
	closed bool
	ready  chan bool
}

func newSyncBuffer() *syncBuffer {
	return &syncBuffer{ready: make(chan bool, 1)}
}

func (b *syncBuffer) Read(p []byte) (n int, err error) {
	for {
		b.mu.RLock()
		n, err = b.buf.Read(p)
		b.mu.RUnlock()
		if n > 0 || b.closed {
			return
		}
		<-b.ready
	}
}

func (b *syncBuffer) signal() {
	select {

// computeRandom returns a cryptographic random float64 in the range [0, 1],
// with 52 bits of precision.
func computeRandom() float64 {
	for {
		b := make([]byte, 8)
		_, err := rand.Read(b)
		if err != nil {
			panic(fmt.Sprintf("rand.Read failed: %v", err))
		}
		// and turn it into a float64
		x := math.Float64frombits(binary.LittleEndian.Uint64(b))
		if math.IsNaN(x) || math.IsInf(x, 0) {
			continue
		}

}

func openBrowser(url string, o *plugin.Options) {
	// Construct URL.
	baseURL, _ := gourl.Parse(url)
	current := currentConfig()
	u, _ := current.makeURL(*baseURL)

	// Give server a little time to get ready.
	time.Sleep(time.Millisecond * 500)

	for _, b := range browsers() {
		args := strings.Split(b, " ")
		if len(args) == 0 {
			continue
		}
		viewer := exec.Command(args[0], append(args[1:], u.String())...)

	objdirSeq int // counter for NewObjdir
	pkgSeq    int

	backgroundSh *Shell // Shell that per-Action Shells are derived from

	exec      sync.Mutex
	readySema chan bool
	ready     actionQueue

	id           sync.Mutex
	toolIDCache  map[string]string // tool name -> tool ID
	buildIDCache map[string]string // file name -> build ID
}

	// return the same package.
	ImportFrom(path, dir string, mode ImportMode) (*Package, error)
}

// A Config specifies the configuration for type checking.
// The zero value for Config is a ready-to-use default configuration.
type Config struct {
	// Context is the context used for resolving global identifiers. If nil, the
	// type checker will initialize this field with a newly created context.
	Context *Context

	"strings"
	"sync"
)

// A Scope maintains a set of objects and links to its containing
// (parent) and contained (children) scopes. Objects may be inserted
// and looked up by name. The zero value for Scope is a ready-to-use
// empty scope.
type Scope struct {
	parent   *Scope
	children []*Scope
	number   int               // parent.children[number-1] is this scope; 0 if there is no parent
	elems    map[string]Object // lazily allocated

	// "linux_386_race" instead of the usual "linux_386".
	InstallSuffix string

	// By default, Import uses the operating system's file system calls
	// to read directories and files. To read from other sources,
	// callers can set the following functions. They all have default
	// behaviors that use the local file system, so clients need only set
	// the functions whose behaviors they wish to change.

func For(obj types.Object) (Path, error) {
	return new(Encoder).For(obj)
}

// An Encoder amortizes the cost of encoding the paths of multiple objects.
// The zero value of an Encoder is ready to use.
type Encoder struct {
	scopeMemo map[*types.Scope][]types.Object // memoization of scopeObjects
}

// For returns the path to an object relative to its package,

	}
	defer lock.Close()
	if err := syscall.Flock(int(lock.Fd()), syscall.LOCK_EX); err != nil {
		return 0, err
	}

	// In case we're booting a device or emulator alongside all.bash, wait for
	// it to be ready. adb wait-for-device is not enough, we have to
	// wait for sys.boot_completed.
	if err := adb("wait-for-device", "exec-out", "while [[ -z $(getprop sys.boot_completed) ]]; do sleep 1; done;"); err != nil {
		return 0, err
	}

	if fi, ok := encoderCache.Load(t); ok {
		return fi.(encoderFunc)
	}

	// To deal with recursive types, populate the map with an
	// indirect func before we build it. This type waits on the
	// real func (f) to be ready and then calls it. This indirect
	// func is only used for recursive types.
	var (
		wg sync.WaitGroup
		f  encoderFunc
	)
	wg.Add(1)