besetmap

Documentation

Overview

Package besetmap parses the Backup Exec proprietary Set Map stream.

The MTF specification (§7.3.3) defines the standard Set Map with stream IDs 'TSMP' (Type 1) and 'MAP2' (Type 2), and the main go-mtf package parses those. Backup Exec (Veritas) instead writes a Set Map whose four-byte stream ID is 'SMP2' (bytes 53 4D 50 32, 0x32504D53 read little-endian). The MTF_100a specification does not mention 'SMP2' and no Backup Exec public reference documenting it has been located; this parser is therefore derived from empirical observation of produced media, not a vendor specification.

The 'SMP2' payload uses the same Set Map header and Set Map Entry fixed fields as the spec, with one material difference: each entry's Number-Of- Volumes volume records follow the entry as separate records in the stream rather than being nested inside the entry's declared LENGTH.

This package registers its parser with mtf.RegisterSetMapParser for the 'SMP2' stream ID on init, so importing it (usually as a blank import) opts the program into Backup Exec Set Map support:

import _ "github.com/pbs-plus/go-mtf/besetmap"

After that import, mtf.Reader.Catalog and mtf.ReadSetMap return fully populated Set Maps from Backup Exec media. Without the import, the main package's spec-only parser is used as a best effort.

Index

• Constants
• func Parse(raw []byte) *mtf.SetMap

Constants

const StreamSMP2 = mtf.StreamSMP2

StreamSMP2 is the four-byte Backup Exec Set Map stream ID, 'SMP2' (the ASCII bytes read as a little-endian uint32). It equals mtf.StreamSM2P / mtf.StreamSMP2.

Functions

func Parse

func Parse(raw []byte) *mtf.SetMap

Parse decodes a Backup Exec 'SMP2' Set Map stream payload (the bytes after the 22-byte stream header) into an *mtf.SetMap. It reads the standard Set Map header, then for each entry decodes the fixed fields via the shared mtf.ParseSetMapEntryFixed helper and reads the entry's declared Number-Of-Volumes volume records as the following records in the stream. It is read-only and tolerant of truncation.