podman

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//go:build !remote
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package libpod
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import (
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	"fmt"
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	"github.com/containers/podman/v5/libpod/define"
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	"github.com/containers/podman/v5/libpod/layers"
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	"github.com/containers/storage/pkg/archive"
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)
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var initInodes = map[string]bool{
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	"/dev":                   true,
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	"/etc/hostname":          true,
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	"/etc/hosts":             true,
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	"/etc/resolv.conf":       true,
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	"/proc":                  true,
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	"/run":                   true,
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	"/run/notify":            true,
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	"/run/.containerenv":     true,
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	"/run/secrets":           true,
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	define.ContainerInitPath: true,
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	"/sys":                   true,
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	"/etc/mtab":              true,
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}
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// GetDiff returns the differences between the two images, layers, or containers
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func (r *Runtime) GetDiff(from, to string, diffType define.DiffType) ([]archive.Change, error) {
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	toLayer, err := r.getLayerID(to, diffType)
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	if err != nil {
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		return nil, err
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	}
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	fromLayer := ""
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	if from != "" {
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		fromLayer, err = r.getLayerID(from, diffType)
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		if err != nil {
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			return nil, err
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		}
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	}
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	var rchanges []archive.Change
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	changes, err := r.store.Changes(fromLayer, toLayer)
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	if err == nil {
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		for _, c := range changes {
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			if initInodes[c.Path] {
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				continue
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			}
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			rchanges = append(rchanges, c)
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		}
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	}
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	return rchanges, err
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}
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// GetLayerID gets a full layer id given a full or partial id
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// If the id matches a container or image, the id of the top layer is returned
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// If the id matches a layer, the top layer id is returned
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func (r *Runtime) getLayerID(id string, diffType define.DiffType) (string, error) {
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	var lastErr error
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	if diffType&define.DiffImage == define.DiffImage {
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		toImage, _, err := r.libimageRuntime.LookupImage(id, nil)
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		if err == nil {
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			return toImage.TopLayer(), nil
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		}
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		lastErr = err
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	}
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	if diffType&define.DiffContainer == define.DiffContainer {
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		toCtr, err := r.store.Container(id)
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		if err == nil {
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			return toCtr.LayerID, nil
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		}
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		lastErr = err
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	}
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	if diffType == define.DiffAll {
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		toLayer, err := layers.FullID(r.store, id)
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		if err == nil {
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			return toLayer, nil
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		}
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		lastErr = err
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	}
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	return "", fmt.Errorf("%s not found: %w", id, lastErr)
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}
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