Method fetch

core/unpack/unpacker.go:657–701

(ctx context.Context, h images.Handler, layers []ocispec.Descriptor, done []chan struct{})

}

func (u *Unpacker) fetch(ctx context.Context, h images.Handler, layers []ocispec.Descriptor, done []chan struct{}) error {
	eg, ctx2 := errgroup.WithContext(ctx)
	for i, desc := range layers {
		ctx2, layerSpan := tracing.StartSpan(ctx2, tracing.Name(unpackSpanPrefix, "fetchLayer"))
		layerSpan.SetAttributes(
			tracing.Attribute("layer.media.type", desc.MediaType),
			tracing.Attribute("layer.media.size", desc.Size),
			tracing.Attribute("layer.media.digest", desc.Digest.String()),
		)
		var ch chan struct{}
		if done != nil {
			ch = done[i]
		}

		if err := u.acquire(ctx, u.limiter); err != nil {
			return err
		}

		eg.Go(func() error {
			defer layerSpan.End()

			unlock, err := u.lockBlobDescriptor(ctx2, desc)
			if err != nil {
				u.release(u.limiter)
				return err
			}

			_, err = h.Handle(ctx2, desc)

			unlock()
			u.release(u.limiter)

			if err != nil && !errors.Is(err, images.ErrSkipDesc) {
				return err
			}
			if ch != nil {
				close(ch)
			}

			return nil
		})
	}

	return eg.Wait()
}

func (u *Unpacker) acquire(ctx context.Context, l Limiter) error {
	if l == nil {