podman

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//go:build !remote
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package generate
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import (
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	"context"
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	"fmt"
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	"os"
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	buildahDefine "github.com/containers/buildah/define"
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	"github.com/containers/common/pkg/config"
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	"github.com/containers/podman/v5/libpod"
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	"github.com/containers/podman/v5/libpod/define"
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)
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// PullOrBuildInfraImage pulls down the specified image or the one set in
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// containers.conf.  If none is set, it builds a local pause image.
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func PullOrBuildInfraImage(rt *libpod.Runtime, imageName string) (string, error) {
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	rtConfig, err := rt.GetConfigNoCopy()
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	if err != nil {
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		return "", err
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	}
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	if imageName == "" {
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		imageName = rtConfig.Engine.InfraImage
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	}
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	if imageName != "" {
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		_, err := rt.LibimageRuntime().Pull(context.Background(), imageName, config.PullPolicyMissing, nil)
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		if err != nil {
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			return "", err
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		}
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		return imageName, nil
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	}
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	name, err := buildPauseImage(rt, rtConfig)
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	if err != nil {
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		return "", fmt.Errorf("building local pause image: %w", err)
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	}
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	return name, nil
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}
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func buildPauseImage(rt *libpod.Runtime, rtConfig *config.Config) (string, error) {
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	version, err := define.GetVersion()
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	if err != nil {
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		return "", err
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	}
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	imageName := fmt.Sprintf("localhost/podman-pause:%s-%d", version.Version, version.Built)
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	// First check if the image has already been built.
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	if _, _, err := rt.LibimageRuntime().LookupImage(imageName, nil); err == nil {
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		return imageName, nil
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	}
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	// Also look into the path as some distributions install catatonit in
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	// /usr/bin.
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	catatonitPath, err := rtConfig.FindInitBinary()
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	if err != nil {
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		return "", fmt.Errorf("finding pause binary: %w", err)
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	}
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	buildContent := fmt.Sprintf(`FROM scratch
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COPY %s /catatonit
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ENTRYPOINT ["/catatonit", "-P"]`, catatonitPath)
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	tmpF, err := os.CreateTemp("", "pause.containerfile")
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	if err != nil {
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		return "", err
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	}
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	if _, err := tmpF.WriteString(buildContent); err != nil {
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		return "", err
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	}
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	if err := tmpF.Close(); err != nil {
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		return "", err
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	}
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	defer os.Remove(tmpF.Name())
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	buildOptions := buildahDefine.BuildOptions{
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		CommonBuildOpts: &buildahDefine.CommonBuildOptions{},
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		Output:          imageName,
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		Quiet:           true,
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		IgnoreFile:      "/dev/null", // makes sure to not read a local .ignorefile (see #13529)
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		IIDFile:         "/dev/null", // prevents Buildah from writing the ID on stdout
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		IDMappingOptions: &buildahDefine.IDMappingOptions{
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			// Use the host UID/GID mappings for the build to avoid issues when
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			// running with a custom mapping (BZ #2083997).
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			HostUIDMapping: true,
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			HostGIDMapping: true,
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		},
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	}
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	if _, _, err := rt.Build(context.Background(), buildOptions, tmpF.Name()); err != nil {
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		return "", err
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	}
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	return imageName, nil
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}
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