talm

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// This Source Code Form is subject to the terms of the Mozilla Public
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// License, v. 2.0. If a copy of the MPL was not distributed with this
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// file, You can obtain one at http://mozilla.org/MPL/2.0/.
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package main
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import (
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	"context"
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	"log"
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	"os"
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	"github.com/aenix-io/talm/internal/app/machined/pkg/runtime/v1alpha1/bootloader"
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	"github.com/aenix-io/talm/internal/pkg/meta"
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)
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func revertBootloader(ctx context.Context) {
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	if err := revertBootloadInternal(ctx); err != nil {
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		log.Printf("failed to revert bootloader: %s", err)
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	}
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}
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func revertBootloadInternal(ctx context.Context) error {
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	metaState, err := meta.New(ctx, nil)
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	if err != nil {
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		if os.IsNotExist(err) {
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			// no META, no way to revert
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			return nil
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		}
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		return err
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	}
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	label, ok := metaState.ReadTag(meta.Upgrade)
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	if !ok {
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		return nil
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	}
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	if label == "" {
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		if _, err = metaState.DeleteTag(ctx, meta.Upgrade); err != nil {
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			return err
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		}
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		return metaState.Flush()
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	}
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	log.Printf("reverting failed upgrade, switching to %q", label)
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	if err = func() error {
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		config, probeErr := bootloader.Probe(ctx, "")
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		if probeErr != nil {
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			if os.IsNotExist(probeErr) {
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				// no bootloader found, nothing to do
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				return nil
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			}
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			return probeErr
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		}
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		return config.Revert(ctx)
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	}(); err != nil {
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		return err
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	}
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	if _, err = metaState.DeleteTag(ctx, meta.Upgrade); err != nil {
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		return err
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	}
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	return metaState.Flush()
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}
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