Method metaFileContents

core/container_exec.go:2261–2308

(ctx context.Context, filePath string)

}

func (container *Container) metaFileContents(ctx context.Context, filePath string) (string, error) {
	if err := container.Evaluate(ctx); err != nil {
		return "", err
	}

	if container.MetaSnapshot == nil {
		return "", ErrNoCommand
	}
	metaSnapshot, ok := container.MetaSnapshot.Peek()
	if !ok || metaSnapshot == nil {
		return "", ErrNoCommand
	}

	query, err := CurrentQuery(ctx)
	if err != nil {
		return "", err
	}
	reopened, err := query.SnapshotManager().GetBySnapshotID(ctx, metaSnapshot.SnapshotID(), bkcache.NoUpdateLastUsed)
	if err != nil {
		return "", err
	}
	defer func() {
		_ = reopened.Release(context.WithoutCancel(ctx))
	}()

	var content []byte
	err = MountRef(ctx, reopened, func(root string, _ *ctrdmount.Mount) error {
		fullPath, err := containerdfs.RootPath(root, filePath)
		if err != nil {
			return err
		}
		content, err = os.ReadFile(fullPath)
		if err != nil {
			return TrimErrPathPrefix(err, root)
		}
		return nil
	}, mountRefAsReadOnly)
	if err != nil {
		if errors.Is(err, errEmptyResultRef) {
			return "", ErrNoCommand
		}
		if errors.Is(err, os.ErrNotExist) {
			return "", ErrNoCommand
		}
		return "", err
	}
	return string(content), nil
}