Initial DDC release

internal/config/libraries.go

@@ -0,0 +1,56 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+func parseLibraryRoots(raw string) ([]string, error) {
+	var roots []string
+	seenRoots := make(map[string]bool)
+
+	for _, entry := range strings.Split(raw, ";") {
+		entry = strings.TrimSpace(entry)
+		if entry == "" {
+			continue
+		}
+
+		root, err := resolveRoot(entry)
+		if err != nil {
+			return nil, err
+		}
+		if seenRoots[root] {
+			continue
+		}
+		seenRoots[root] = true
+		roots = append(roots, root)
+	}
+
+	if len(roots) == 0 {
+		return nil, errors.New("LIBRARY_ROOTS must list at least one folder")
+	}
+	return roots, nil
+}
+
+func resolveRoot(entry string) (string, error) {
+	cleaned := filepath.Clean(entry)
+	if !filepath.IsAbs(cleaned) || cleaned == "/" {
+		return "", fmt.Errorf("LIBRARY_ROOTS: invalid path %q", entry)
+	}
+
+	resolved, err := filepath.EvalSymlinks(cleaned)
+	if err != nil {
+		return "", fmt.Errorf("LIBRARY_ROOTS: %w", err)
+	}
+	info, err := os.Stat(resolved)
+	if err != nil {
+		return "", fmt.Errorf("LIBRARY_ROOTS: %w", err)
+	}
+	if !info.IsDir() {
+		return "", fmt.Errorf("LIBRARY_ROOTS: %q is not a directory", entry)
+	}
+	return resolved, nil
+}