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//go:build !windows
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package server
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import (
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	"fmt"
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	"os"
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	"path/filepath"
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)
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func prepareKVProviderDirectory(dir string) error {
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	dir = filepath.Clean(dir)
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	info, err := os.Stat(dir)
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	if err == nil {
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		if !info.IsDir() {
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			return fmt.Errorf("data path %q is not a directory", dir)
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		}
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		return nil
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	}
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	if !os.IsNotExist(err) {
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		return err
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	}
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	parent := filepath.Dir(dir)
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	if parent == dir {
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		return err
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	}
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	if err := prepareKVProviderDirectory(parent); err != nil {
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		return err
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	}
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	err = os.Mkdir(dir, 0750)
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	created := err == nil
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	if err != nil && !os.IsExist(err) {
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		return err
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	}
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	if !created {
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		info, err := os.Stat(dir)
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		if err != nil {
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			return err
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		}
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		if !info.IsDir() {
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			return fmt.Errorf("data path %q is not a directory", dir)
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		}
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	}
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	// Persist each new directory's name before creating a child or marker.
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	// Existing ancestors need only traversal permission and are left alone.
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	if err := syncKVProviderIdentity(parent); err != nil {
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		if created {
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			// Only remove this initialization's empty directory. A retry must
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			// not mistake a failed creation flush for an established directory.
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			_ = os.Remove(dir)
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		}
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		return err
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	}
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	return nil
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}
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func publishKVProviderMarker(tempPath, dir string) error {
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	// A hard link publishes the complete, synced marker atomically and never
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	// overwrites an identity established by a concurrent startup.
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	if err := os.Link(tempPath, filepath.Join(dir, kvProviderMarker)); err != nil {
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		return err
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	}
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	if err := os.Remove(tempPath); err != nil {
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		return fmt.Errorf("removing temporary marker: %w", err)
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	}
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	return syncKVProviderIdentity(dir)
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}
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func syncKVProviderIdentity(dir string) error {
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	d, err := os.Open(dir)
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	if err != nil {
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		return fmt.Errorf("opening directory to sync storage identity: %w", err)
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	}
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	syncErr := d.Sync()
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	closeErr := d.Close()
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	if syncErr != nil {
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		return fmt.Errorf("syncing directory for storage identity: %w", syncErr)
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	}
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	if closeErr != nil {
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		return fmt.Errorf("closing directory after syncing storage identity: %w", closeErr)
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	}
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	return nil
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}