// WriteAt should not affect nor be affected by the underlying
// seek offset.
//
// Clients of WriteAt can execute parallel WriteAt calls on the same
// destination if the ranges do not overlap.
//
// Implementations must not retain p.
type WriterAt interface {
	WriteAt(p []byte, off int64) (n int, err error)
}

// ByteReader is the interface that wraps the ReadByte method.
//

	for i := range w.buffer {
		delete(w.buffer, i)
	}
	w.wg.Wait()
	return err
}

type writerAt struct {
	w      *io.PipeWriter
	r      *io.PipeReader
	wg     *sync.WaitGroup
	buffer map[int64][]byte
	err    error

	nextOffset int64
	m          sync.Mutex
}

func (w *writerAt) WriteAt(b []byte, offset int64) (n int, err error) {
	w.m.Lock()
	defer w.m.Unlock()

import org.gradle.internal.serialize.graph.WriteContext
import org.gradle.internal.serialize.graph.writeMap


object ImmutableMapCodec : Codec<ImmutableMap<Any, Any>> {

    override suspend fun WriteContext.encode(value: ImmutableMap<Any, Any>) {
        writeMap(value)
    }

    override suspend fun ReadContext.decode(): ImmutableMap<Any, Any>? {
        val size = readSmallInt()

    {
        write(it.comparator())
        writeMap(it)
    },
    {
        @Suppress("unchecked_cast")
        val comparator = read() as Comparator<Any?>?
        readMapInto { TreeMap(comparator) }
    }
)


fun <T : MutableMap<Any?, Any?>> mapCodec(factory: (Int) -> T): Codec<T> = codec(
    { writeMap(it) },
    { readMapInto(factory) }

func (r loadCmdReader) ReadAt(offset int64, data interface{}) error {
	if _, err := r.f.Seek(r.offset+offset, 0); err != nil {
		return err
	}
	return binary.Read(r.f, r.order, data)
}

func (r loadCmdReader) WriteAt(offset int64, data interface{}) error {
	if _, err := r.f.Seek(r.offset+offset, 0); err != nil {
		return err
	}
	return binary.Write(r.f, r.order, data)
}

var errWriteAtInAppendMode = errors.New("os: invalid use of WriteAt on file opened with O_APPEND")

// WriteAt writes len(b) bytes to the File starting at byte offset off.
// It returns the number of bytes written and an error, if any.
// WriteAt returns a non-nil error when n != len(b).
//
// If file was opened with the O_APPEND flag, WriteAt returns an error.
func (f *File) WriteAt(b []byte, off int64) (n int, err error) {

			return err
		}
		if cmd.Cmd == LC_UUID {
			var u uuidCmd
			if err := reader.ReadAt(0, &u); err != nil {
				return err
			}
			copy(u.Uuid[:], uuidFromGoBuildId(*flagBuildid))
			if err := reader.WriteAt(0, &u); err != nil {
				return err
			}
			break
		}
	}

	// We're done
	return nil

}


suspend fun <T : MutableCollection<Any?>> ReadContext.readCollectionInto(factory: (Int) -> T): T =
    readCollectionInto(factory) { read() }


suspend fun WriteContext.writeMap(value: Map<*, *>) {
    writeSmallInt(value.size)
    writeMapEntries(value)
}


suspend fun WriteContext.writeMapEntries(value: Map<*, *>) {
    for (entry in value.entries) {
        write(entry.key)

		return nil, err
	}

	// Establish file header and initial data area if not already present.
	if info.Size() < minFileLen {
		if _, err := f.WriteAt(hdr, 0); err != nil {
			return nil, err
		}
		// Write zeros at the end of the file to extend it to minFileLen.
		if _, err := f.WriteAt(m.zero[:], int64(minFileLen-len(m.zero))); err != nil {
			return nil, err
		}
		info, err = f.Stat()
		if err != nil {
			return nil, err

		t.Errorf("WriteAt(-10) = %v, %v; want 0, ...%q...", n, err, wantsub)
	}
}

// Verify that WriteAt doesn't work in append mode.
func TestWriteAtInAppendMode(t *testing.T) {
	defer chtmpdir(t)()
	f, err := OpenFile("write_at_in_append_mode.txt", O_APPEND|O_CREATE, 0666)
	if err != nil {
		t.Fatalf("OpenFile: %v", err)
	}
	defer f.Close()

	_, err = f.WriteAt([]byte(""), 1)