なんかもうめっちゃ変えた

packages/backend/src/misc/prelude/xml.ts

@@ -0,0 +1,41 @@
+const map: Record<string, string> = {
+	'&': '&amp;',
+	'<': '&lt;',
+	'>': '&gt;',
+	'"': '&quot;',
+	'\'': '&apos;',
+};
+
+const beginingOfCDATA = '<![CDATA[';
+const endOfCDATA = ']]>';
+
+export function escapeValue(x: string): string {
+	let insideOfCDATA = false;
+	let builder = '';
+	for (
+		let i = 0;
+		i < x.length;
+	) {
+		if (insideOfCDATA) {
+			if (x.slice(i, i + beginingOfCDATA.length) === beginingOfCDATA) {
+				insideOfCDATA = true;
+				i += beginingOfCDATA.length;
+			} else {
+				builder += x[i++];
+			}
+		} else {
+			if (x.slice(i, i + endOfCDATA.length) === endOfCDATA) {
+				insideOfCDATA = false;
+				i += endOfCDATA.length;
+			} else {
+				const b = x[i++];
+				builder += map[b] || b;
+			}
+		}
+	}
+	return builder;
+}
+
+export function escapeAttribute(x: string): string {
+	return Object.entries(map).reduce((a, [k, v]) => a.replace(k, v), x);
+}