OLE2 containers

MS-CFB · NAMED STREAMS

parseOle2 returns a checked document union by default. Explicit expect: cfb selects a CfbDocument container view for any valid compound file; this does not imply Office record semantics are decoded.

Container model

Use stream(path).bytes to inspect or replace an existing stream by full storage path, then serialize().

• V3 regular/mini growth, shrink, emptying and transitions preserve hierarchy, unknown streams and directory metadata.
• V4 regular-stream resizing validates 4096-byte sectors and directory counts.
• New storage entries, external DIFAT expansion and variable-length v4 mini edits remain unsupported.

Detection and diagnostics

Automatic parsing falls back to a CFB view with explicit diagnostics for ambiguous or unsupported Office models. Checked Office expectations throw instead.

• Container stream edits do not repair offsets inside Office records.
• Compatibility entries/getStream remain; returned inspection data is detached from owned bytes.
• parseCompoundFile names the original raw reader.

Directory entries expose exact createdFileTime and modifiedFileTime bigint ticks alongside the millisecond Date views. listCompoundFile and repairCompoundFile retain those ticks, including sub-millisecond precision. Changing a listed Date writes the new date; to unset a timestamp, clear both its Date and raw FILETIME fields. Invalid or out-of-range timestamps are refused.

Example

import { parseOle2 } from '@christophervr/ole2';

const container = parseOle2(bytes, { expect: 'cfb' });
const stream = container.stream(['Custom', 'Data']);
stream.bytes = new Uint8Array([1, 2, 3]);
const saved = container.serialize();