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Diffstat (limited to 'libpod/image/layer_tree.go')
-rw-r--r--libpod/image/layer_tree.go239
1 files changed, 0 insertions, 239 deletions
diff --git a/libpod/image/layer_tree.go b/libpod/image/layer_tree.go
deleted file mode 100644
index aa3084449..000000000
--- a/libpod/image/layer_tree.go
+++ /dev/null
@@ -1,239 +0,0 @@
-package image
-
-import (
- "context"
-
- ociv1 "github.com/opencontainers/image-spec/specs-go/v1"
- "github.com/sirupsen/logrus"
-)
-
-// layerTree is an internal representation of local layers.
-type layerTree struct {
- // nodes is the actual layer tree with layer IDs being keys.
- nodes map[string]*layerNode
- // ociCache is a cache for Image.ID -> OCI Image. Translations are done
- // on-demand.
- ociCache map[string]*ociv1.Image
-}
-
-// node returns a layerNode for the specified layerID.
-func (t *layerTree) node(layerID string) *layerNode {
- node, exists := t.nodes[layerID]
- if !exists {
- node = &layerNode{}
- t.nodes[layerID] = node
- }
- return node
-}
-
-// toOCI returns an OCI image for the specified image.
-func (t *layerTree) toOCI(ctx context.Context, i *Image) (*ociv1.Image, error) {
- var err error
- oci, exists := t.ociCache[i.ID()]
- if !exists {
- oci, err = i.ociv1Image(ctx)
- if err == nil {
- t.ociCache[i.ID()] = oci
- }
- }
- return oci, err
-}
-
-// layerNode is a node in a layerTree. It's ID is the key in a layerTree.
-type layerNode struct {
- children []*layerNode
- images []*Image
- parent *layerNode
-}
-
-// layerTree extracts a layerTree from the layers in the local storage and
-// relates them to the specified images.
-func (ir *Runtime) layerTree() (*layerTree, error) {
- layers, err := ir.store.Layers()
- if err != nil {
- return nil, err
- }
-
- images, err := ir.GetImages()
- if err != nil {
- return nil, err
- }
-
- tree := layerTree{
- nodes: make(map[string]*layerNode),
- ociCache: make(map[string]*ociv1.Image),
- }
-
- // First build a tree purely based on layer information.
- for _, layer := range layers {
- node := tree.node(layer.ID)
- if layer.Parent == "" {
- continue
- }
- parent := tree.node(layer.Parent)
- node.parent = parent
- parent.children = append(parent.children, node)
- }
-
- // Now assign the images to each (top) layer.
- for i := range images {
- img := images[i] // do not leak loop variable outside the scope
- topLayer := img.TopLayer()
- if topLayer == "" {
- continue
- }
- node, exists := tree.nodes[topLayer]
- if !exists {
- // Note: erroring out in this case has turned out having been a
- // mistake. Users may not be able to recover, so we're now
- // throwing a warning to guide them to resolve the issue and
- // turn the errors non-fatal.
- logrus.Warnf("Top layer %s of image %s not found in layer tree. The storage may be corrupted, consider running `podman system reset`.", topLayer, img.ID())
- continue
- }
- node.images = append(node.images, img)
- }
-
- return &tree, nil
-}
-
-// children returns the image IDs of children . Child images are images
-// with either the same top layer as parent or parent being the true parent
-// layer. Furthermore, the history of the parent and child images must match
-// with the parent having one history item less.
-// If all is true, all images are returned. Otherwise, the first image is
-// returned.
-func (t *layerTree) children(ctx context.Context, parent *Image, all bool) ([]string, error) {
- if parent.TopLayer() == "" {
- return nil, nil
- }
-
- var children []string
-
- parentNode, exists := t.nodes[parent.TopLayer()]
- if !exists {
- // Note: erroring out in this case has turned out having been a
- // mistake. Users may not be able to recover, so we're now
- // throwing a warning to guide them to resolve the issue and
- // turn the errors non-fatal.
- logrus.Warnf("Layer %s not found in layer. The storage may be corrupted, consider running `podman system reset`.", parent.TopLayer())
- return children, nil
- }
-
- parentID := parent.ID()
- parentOCI, err := t.toOCI(ctx, parent)
- if err != nil {
- return nil, err
- }
-
- // checkParent returns true if child and parent are in such a relation.
- checkParent := func(child *Image) (bool, error) {
- if parentID == child.ID() {
- return false, nil
- }
- childOCI, err := t.toOCI(ctx, child)
- if err != nil {
- return false, err
- }
- // History check.
- return areParentAndChild(parentOCI, childOCI), nil
- }
-
- // addChildrenFrom adds child images of parent to children. Returns
- // true if any image is a child of parent.
- addChildrenFromNode := func(node *layerNode) (bool, error) {
- foundChildren := false
- for _, childImage := range node.images {
- isChild, err := checkParent(childImage)
- if err != nil {
- return foundChildren, err
- }
- if isChild {
- foundChildren = true
- children = append(children, childImage.ID())
- if all {
- return foundChildren, nil
- }
- }
- }
- return foundChildren, nil
- }
-
- // First check images where parent's top layer is also the parent
- // layer.
- for _, childNode := range parentNode.children {
- found, err := addChildrenFromNode(childNode)
- if err != nil {
- return nil, err
- }
- if found && all {
- return children, nil
- }
- }
-
- // Now check images with the same top layer.
- if _, err := addChildrenFromNode(parentNode); err != nil {
- return nil, err
- }
-
- return children, nil
-}
-
-// parent returns the parent image or nil if no parent image could be found.
-func (t *layerTree) parent(ctx context.Context, child *Image) (*Image, error) {
- if child.TopLayer() == "" {
- return nil, nil
- }
-
- node, exists := t.nodes[child.TopLayer()]
- if !exists {
- // Note: erroring out in this case has turned out having been a
- // mistake. Users may not be able to recover, so we're now
- // throwing a warning to guide them to resolve the issue and
- // turn the errors non-fatal.
- logrus.Warnf("Layer %s not found in layer. The storage may be corrupted, consider running `podman system reset`.", child.TopLayer())
- return nil, nil
- }
-
- childOCI, err := t.toOCI(ctx, child)
- if err != nil {
- return nil, err
- }
-
- // Check images from the parent node (i.e., parent layer) and images
- // with the same layer (i.e., same top layer).
- childID := child.ID()
- images := node.images
- if node.parent != nil {
- images = append(images, node.parent.images...)
- }
- for _, parent := range images {
- if parent.ID() == childID {
- continue
- }
- parentOCI, err := t.toOCI(ctx, parent)
- if err != nil {
- return nil, err
- }
- // History check.
- if areParentAndChild(parentOCI, childOCI) {
- return parent, nil
- }
- }
-
- return nil, nil
-}
-
-// hasChildrenAndParent returns true if the specified image has children and a
-// parent.
-func (t *layerTree) hasChildrenAndParent(ctx context.Context, i *Image) (bool, error) {
- children, err := t.children(ctx, i, false)
- if err != nil {
- return false, err
- }
- if len(children) == 0 {
- return false, nil
- }
- parent, err := t.parent(ctx, i)
- return parent != nil, err
-}