APM (Apple Partition Map) partition table: Java parsing library

This page hosts a formal specification of APM (Apple Partition Map) partition table using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for Java generated by Kaitai Struct depends on the Java runtime library. You have to install it before you can parse data.

The Java runtime library is published in the Maven Central Repository. Refer to the artifact page for instructions how to add it into your project with the build tool that you use.

Code

Parse a local file and get structure in memory:

ApmPartitionTable data = ApmPartitionTable.fromFile("path/to/local/file.APM (Apple Partition Map) partition table");

Or parse structure from a byte array:

byte[] someArray = new byte[] { ... };
ApmPartitionTable data = new ApmPartitionTable(new ByteBufferKaitaiStream(someArray));

After that, one can get various attributes from the structure by invoking getter methods like:

data.sectorSize() // => 0x200 (512) bytes for disks, 0x1000 (4096) bytes is not supported by APM
0x800 (2048) bytes for CDROM

Java source code to parse APM (Apple Partition Map) partition table

ApmPartitionTable.java

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

import io.kaitai.struct.ByteBufferKaitaiStream;
import io.kaitai.struct.KaitaiStruct;
import io.kaitai.struct.KaitaiStream;
import java.io.IOException;
import java.util.Arrays;
import java.nio.charset.Charset;
import java.util.ArrayList;


/**
 * @see <a href="https://en.wikipedia.org/wiki/Apple_Partition_Map">Source</a>
 */
public class ApmPartitionTable extends KaitaiStruct {
    public static ApmPartitionTable fromFile(String fileName) throws IOException {
        return new ApmPartitionTable(new ByteBufferKaitaiStream(fileName));
    }

    public ApmPartitionTable(KaitaiStream _io) {
        this(_io, null, null);
    }

    public ApmPartitionTable(KaitaiStream _io, KaitaiStruct _parent) {
        this(_io, _parent, null);
    }

    public ApmPartitionTable(KaitaiStream _io, KaitaiStruct _parent, ApmPartitionTable _root) {
        super(_io);
        this._parent = _parent;
        this._root = _root == null ? this : _root;
        _read();
    }
    private void _read() {
    }
    public static class PartitionEntry extends KaitaiStruct {
        public static PartitionEntry fromFile(String fileName) throws IOException {
            return new PartitionEntry(new ByteBufferKaitaiStream(fileName));
        }

        public PartitionEntry(KaitaiStream _io) {
            this(_io, null, null);
        }

        public PartitionEntry(KaitaiStream _io, ApmPartitionTable _parent) {
            this(_io, _parent, null);
        }

        public PartitionEntry(KaitaiStream _io, ApmPartitionTable _parent, ApmPartitionTable _root) {
            super(_io);
            this._parent = _parent;
            this._root = _root;
            _read();
        }
        private void _read() {
            this.magic = this._io.readBytes(2);
            if (!(Arrays.equals(magic(), new byte[] { 80, 77 }))) {
                throw new KaitaiStream.ValidationNotEqualError(new byte[] { 80, 77 }, magic(), _io(), "/types/partition_entry/seq/0");
            }
            this.reserved1 = this._io.readBytes(2);
            this.numberOfPartitions = this._io.readU4be();
            this.partitionStart = this._io.readU4be();
            this.partitionSize = this._io.readU4be();
            this.partitionName = new String(KaitaiStream.bytesTerminate(this._io.readBytes(32), (byte) 0, false), Charset.forName("ascii"));
            this.partitionType = new String(KaitaiStream.bytesTerminate(this._io.readBytes(32), (byte) 0, false), Charset.forName("ascii"));
            this.dataStart = this._io.readU4be();
            this.dataSize = this._io.readU4be();
            this.partitionStatus = this._io.readU4be();
            this.bootCodeStart = this._io.readU4be();
            this.bootCodeSize = this._io.readU4be();
            this.bootLoaderAddress = this._io.readU4be();
            this.reserved2 = this._io.readBytes(4);
            this.bootCodeEntry = this._io.readU4be();
            this.reserved3 = this._io.readBytes(4);
            this.bootCodeCksum = this._io.readU4be();
            this.processorType = new String(KaitaiStream.bytesTerminate(this._io.readBytes(16), (byte) 0, false), Charset.forName("ascii"));
        }
        private byte[] partition;
        public byte[] partition() {
            if (this.partition != null)
                return this.partition;
            if ((partitionStatus() & 1) != 0) {
                KaitaiStream io = _root._io();
                long _pos = io.pos();
                io.seek((partitionStart() * _root.sectorSize()));
                this.partition = io.readBytes((partitionSize() * _root.sectorSize()));
                io.seek(_pos);
            }
            return this.partition;
        }
        private byte[] data;
        public byte[] data() {
            if (this.data != null)
                return this.data;
            KaitaiStream io = _root._io();
            long _pos = io.pos();
            io.seek((dataStart() * _root.sectorSize()));
            this.data = io.readBytes((dataSize() * _root.sectorSize()));
            io.seek(_pos);
            return this.data;
        }
        private byte[] bootCode;
        public byte[] bootCode() {
            if (this.bootCode != null)
                return this.bootCode;
            KaitaiStream io = _root._io();
            long _pos = io.pos();
            io.seek((bootCodeStart() * _root.sectorSize()));
            this.bootCode = io.readBytes(bootCodeSize());
            io.seek(_pos);
            return this.bootCode;
        }
        private byte[] magic;
        private byte[] reserved1;
        private long numberOfPartitions;
        private long partitionStart;
        private long partitionSize;
        private String partitionName;
        private String partitionType;
        private long dataStart;
        private long dataSize;
        private long partitionStatus;
        private long bootCodeStart;
        private long bootCodeSize;
        private long bootLoaderAddress;
        private byte[] reserved2;
        private long bootCodeEntry;
        private byte[] reserved3;
        private long bootCodeCksum;
        private String processorType;
        private ApmPartitionTable _root;
        private ApmPartitionTable _parent;
        public byte[] magic() { return magic; }
        public byte[] reserved1() { return reserved1; }
        public long numberOfPartitions() { return numberOfPartitions; }

        /**
         * First sector
         */
        public long partitionStart() { return partitionStart; }

        /**
         * Number of sectors
         */
        public long partitionSize() { return partitionSize; }
        public String partitionName() { return partitionName; }
        public String partitionType() { return partitionType; }

        /**
         * First sector
         */
        public long dataStart() { return dataStart; }

        /**
         * Number of sectors
         */
        public long dataSize() { return dataSize; }
        public long partitionStatus() { return partitionStatus; }

        /**
         * First sector
         */
        public long bootCodeStart() { return bootCodeStart; }

        /**
         * Number of bytes
         */
        public long bootCodeSize() { return bootCodeSize; }

        /**
         * Address of bootloader code
         */
        public long bootLoaderAddress() { return bootLoaderAddress; }
        public byte[] reserved2() { return reserved2; }

        /**
         * Boot code entry point
         */
        public long bootCodeEntry() { return bootCodeEntry; }
        public byte[] reserved3() { return reserved3; }

        /**
         * Boot code checksum
         */
        public long bootCodeCksum() { return bootCodeCksum; }
        public String processorType() { return processorType; }
        public ApmPartitionTable _root() { return _root; }
        public ApmPartitionTable _parent() { return _parent; }
    }
    private Integer sectorSize;

    /**
     * 0x200 (512) bytes for disks, 0x1000 (4096) bytes is not supported by APM
     * 0x800 (2048) bytes for CDROM
     */
    public Integer sectorSize() {
        if (this.sectorSize != null)
            return this.sectorSize;
        int _tmp = (int) (512);
        this.sectorSize = _tmp;
        return this.sectorSize;
    }
    private PartitionEntry partitionLookup;

    /**
     * Every partition entry contains the number of partition entries.
     * We parse the first entry, to know how many to parse, including the first one.
     * No logic is given what to do if other entries have a different number.
     */
    public PartitionEntry partitionLookup() {
        if (this.partitionLookup != null)
            return this.partitionLookup;
        KaitaiStream io = _root._io();
        long _pos = io.pos();
        io.seek(_root.sectorSize());
        this._raw_partitionLookup = io.readBytes(sectorSize());
        KaitaiStream _io__raw_partitionLookup = new ByteBufferKaitaiStream(_raw_partitionLookup);
        this.partitionLookup = new PartitionEntry(_io__raw_partitionLookup, this, _root);
        io.seek(_pos);
        return this.partitionLookup;
    }
    private ArrayList<PartitionEntry> partitionEntries;
    public ArrayList<PartitionEntry> partitionEntries() {
        if (this.partitionEntries != null)
            return this.partitionEntries;
        KaitaiStream io = _root._io();
        long _pos = io.pos();
        io.seek(_root.sectorSize());
        this._raw_partitionEntries = new ArrayList<byte[]>(((Number) (_root.partitionLookup().numberOfPartitions())).intValue());
        partitionEntries = new ArrayList<PartitionEntry>(((Number) (_root.partitionLookup().numberOfPartitions())).intValue());
        for (int i = 0; i < _root.partitionLookup().numberOfPartitions(); i++) {
            this._raw_partitionEntries.add(io.readBytes(sectorSize()));
            KaitaiStream _io__raw_partitionEntries = new ByteBufferKaitaiStream(_raw_partitionEntries.get(_raw_partitionEntries.size() - 1));
            this.partitionEntries.add(new PartitionEntry(_io__raw_partitionEntries, this, _root));
        }
        io.seek(_pos);
        return this.partitionEntries;
    }
    private ApmPartitionTable _root;
    private KaitaiStruct _parent;
    private byte[] _raw_partitionLookup;
    private ArrayList<byte[]> _raw_partitionEntries;
    public ApmPartitionTable _root() { return _root; }
    public KaitaiStruct _parent() { return _parent; }
    public byte[] _raw_partitionLookup() { return _raw_partitionLookup; }
    public ArrayList<byte[]> _raw_partitionEntries() { return _raw_partitionEntries; }
}