talos

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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 utils
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import (
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	"fmt"
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	"os"
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	"syscall"
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	"github.com/dustin/go-humanize"
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)
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// CreateRawDisk creates a raw disk image of the specified size.
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func CreateRawDisk(printf func(string, ...any), path string, diskSize int64) error {
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	printf("creating raw disk of size %s", humanize.Bytes(uint64(diskSize)))
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	f, err := os.Create(path)
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	if err != nil {
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		return fmt.Errorf("failed to create raw disk: %w", err)
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	}
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	defer f.Close() //nolint:errcheck
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	if err = f.Truncate(diskSize); err != nil {
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		return fmt.Errorf("failed to create raw disk: %w", err)
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	}
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	if err = syscall.Fallocate(int(f.Fd()), 0, 0, diskSize); err != nil {
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		fmt.Fprintf(os.Stderr, "WARNING: failed to preallocate disk space for %q (size %d): %s", path, diskSize, err)
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	}
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	return f.Close()
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}
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