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Separate Lisa tag decoding from Lisa filesystem and added

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Priam tags.
This commit is contained in:
Natalia Portillo
2016-08-21 19:23:58 +01:00
parent 985dc6333e
commit 8a50d402c5
12 changed files with 406 additions and 91 deletions
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6
DiscImageChef.Decoders/ChangeLog
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@@ -1,3 +1,9 @@
2016-08-21 Natalia Portillo <claunia@claunia.com>
* LisaTag.cs:
* DiscImageChef.Decoders.csproj: Separate Lisa tag decoding
from Lisa filesystem and added Priam tags.
2016-08-18 Natalia Portillo <claunia@claunia.com>
* ATIP.cs: Make ATIP manufacturer resolver a public method.

1
DiscImageChef.Decoders/DiscImageChef.Decoders.csproj
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@@ -91,6 +91,7 @@
<Compile Include="SCSI\SSC\DensitySupport.cs" />
<Compile Include="SCSI\Types.cs" />
<Compile Include="SCSI\ModesEncoders.cs" />
<Compile Include="LisaTag.cs" />
</ItemGroup>
<Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
<ItemGroup>

360
DiscImageChef.Decoders/LisaTag.cs Normal file
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@@ -0,0 +1,360 @@
// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename : LisaTag.cs
// Author(s) : Natalia Portillo <claunia@claunia.com>
//
// Component : Component
//
// --[ Description ] ----------------------------------------------------------
//
// Description
//
// --[ License ] --------------------------------------------------------------
//
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 2.1 of the
// License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2016 Natalia Portillo
// ****************************************************************************/
using System;
namespace DiscImageChef.Decoders
{
public static class LisaTag
{
/// <summary>
/// LisaOS tag as stored on Apple Profile and FileWare disks (20 bytes)
/// </summary>
public struct ProfileTag
{
/// <summary>0x00, Lisa OS version number</summary>
public ushort version;
/// <summary>0x02 bits 7 to 6, kind of info in this block</summary>
public byte kind;
/// <summary>0x02 bits 5 to 0, reserved</summary>
public byte reserved;
/// <summary>0x03, disk volume number</summary>
public byte volume;
/// <summary>0x04, file ID</summary>
public short fileID;
/// <summary>
/// 0x06 bit 7, checksum valid?
/// </summary>
public bool validChk;
/// <summary>
/// 0x06 bits 6 to 0, used bytes in block
/// </summary>
public ushort usedBytes;
/// <summary>
/// 0x08, 3 bytes, absolute page number
/// </summary>
public uint absPage;
/// <summary>
/// 0x0B, checksum of data
/// </summary>
public byte checksum;
/// <summary>
/// 0x0C, relative page number
/// </summary>
public ushort relPage;
/// <summary>
/// 0x0E, 3 bytes, next block, 0xFFFFFF if it's last block
/// </summary>
public uint nextBlock;
/// <summary>
/// 0x11, 3 bytes, previous block, 0xFFFFFF if it's first block
/// </summary>
public uint prevBlock;
/// <summary>On-memory value for easy first block search.</summary>
public bool isFirst;
/// <summary>On-memory value for easy last block search.</summary>
public bool isLast;
}
/// <summary>
/// LisaOS tag as stored on Priam DataTower disks (24 bytes)
/// </summary>
public struct PriamTag
{
/// <summary>0x00, Lisa OS version number</summary>
public ushort version;
/// <summary>0x02 bits 7 to 6, kind of info in this block</summary>
public byte kind;
/// <summary>0x02 bits 5 to 0, reserved</summary>
public byte reserved;
/// <summary>0x03, disk volume number</summary>
public byte volume;
/// <summary>0x04, file ID</summary>
public short fileID;
/// <summary>
/// 0x06 bit 7, checksum valid?
/// </summary>
public bool validChk;
/// <summary>
/// 0x06 bits 6 to 0, used bytes in block
/// </summary>
public ushort usedBytes;
/// <summary>
/// 0x08, 3 bytes, absolute page number
/// </summary>
public uint absPage;
/// <summary>
/// 0x0B, checksum of data
/// </summary>
public byte checksum;
/// <summary>
/// 0x0C, relative page number
/// </summary>
public ushort relPage;
/// <summary>
/// 0x0E, 3 bytes, next block, 0xFFFFFF if it's last block
/// </summary>
public uint nextBlock;
/// <summary>
/// 0x11, 3 bytes, previous block, 0xFFFFFF if it's first block
/// </summary>
public uint prevBlock;
/// <summary>
/// 0x14, disk size
/// </summary>
public uint diskSize;
/// <summary>On-memory value for easy first block search.</summary>
public bool isFirst;
/// <summary>On-memory value for easy last block search.</summary>
public bool isLast;
}
/// <summary>
/// LisaOS tag as stored on Apple Sony disks (12 bytes)
/// </summary>
public struct SonyTag
{
/// <summary>0x00, Lisa OS version number</summary>
public ushort version;
/// <summary>0x02 bits 7 to 6, kind of info in this block</summary>
public byte kind;
/// <summary>0x02 bits 5 to 0, reserved</summary>
public byte reserved;
/// <summary>0x03, disk volume number</summary>
public byte volume;
/// <summary>0x04, file ID</summary>
public short fileID;
/// <summary>
/// 0x06, relative page number
/// </summary>
public ushort relPage;
/// <summary>
/// 0x08, 3 bytes, next block, 0x7FF if it's last block, 0x8000 set if block is valid
/// </summary>
public ushort nextBlock;
/// <summary>
/// 0x0A, 3 bytes, previous block, 0x7FF if it's first block
/// </summary>
public ushort prevBlock;
/// <summary>On-memory value for easy first block search.</summary>
public bool isFirst;
/// <summary>On-memory value for easy last block search.</summary>
public bool isLast;
}
public static SonyTag? DecodeSonyTag(byte[] tag)
{
if(tag == null || tag.Length != 12)
return null;
SonyTag snTag = new SonyTag();
BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian;
byte[] tmp = new byte[4];
snTag.version = BigEndianBitConverter.ToUInt16(tag, 0);
snTag.kind = (byte)((tag[2] & 0xC0) >> 6);
snTag.reserved = (byte)(tag[2] & 0x3F);
snTag.volume = tag[3];
snTag.fileID = BigEndianBitConverter.ToInt16(tag, 4);
snTag.relPage = BigEndianBitConverter.ToUInt16(tag, 6);
snTag.nextBlock = (ushort)(BigEndianBitConverter.ToUInt16(tag, 8) & 0x7FF);
snTag.prevBlock = (ushort)(BigEndianBitConverter.ToUInt16(tag, 10) & 0x7FF);
snTag.isLast = snTag.nextBlock == 0x7FF;
snTag.isFirst = snTag.prevBlock == 0x7FF;
return snTag;
}
public static ProfileTag? DecodeProfileTag(byte[] tag)
{
if(tag == null || tag.Length != 20)
return null;
ProfileTag phTag = new ProfileTag();
BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian;
byte[] tmp = new byte[4];
phTag.version = BigEndianBitConverter.ToUInt16(tag, 0);
phTag.kind = (byte)((tag[2] & 0xC0) >> 6);
phTag.reserved = (byte)(tag[2] & 0x3F);
phTag.volume = tag[3];
phTag.fileID = BigEndianBitConverter.ToInt16(tag, 4);
phTag.validChk |= (tag[6] & 0x80) == 0x80;
phTag.usedBytes = (ushort)(BigEndianBitConverter.ToUInt16(tag, 6) & 0x7FFF);
tmp[0] = 0x00;
tmp[1] = tag[8];
tmp[2] = tag[9];
tmp[3] = tag[10];
phTag.absPage = BigEndianBitConverter.ToUInt32(tmp, 0);
phTag.checksum = tag[11];
phTag.relPage = BigEndianBitConverter.ToUInt16(tag, 12);
tmp[0] = 0x00;
tmp[1] = tag[14];
tmp[2] = tag[15];
tmp[3] = tag[16];
phTag.nextBlock = BigEndianBitConverter.ToUInt32(tmp, 0);
tmp[0] = 0x00;
tmp[1] = tag[17];
tmp[2] = tag[18];
tmp[3] = tag[19];
phTag.prevBlock = BigEndianBitConverter.ToUInt32(tmp, 0);
phTag.isLast = phTag.nextBlock == 0xFFFFFF;
phTag.isFirst = phTag.prevBlock == 0xFFFFFF;
return phTag;
}
public static PriamTag? DecodePriamTag(byte[] tag)
{
if(tag == null || tag.Length != 24)
return null;
PriamTag pmTag = new PriamTag();
BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian;
byte[] tmp = new byte[4];
pmTag.version = BigEndianBitConverter.ToUInt16(tag, 0);
pmTag.kind = (byte)((tag[2] & 0xC0) >> 6);
pmTag.reserved = (byte)(tag[2] & 0x3F);
pmTag.volume = tag[3];
pmTag.fileID = BigEndianBitConverter.ToInt16(tag, 4);
pmTag.validChk |= (tag[6] & 0x80) == 0x80;
pmTag.usedBytes = (ushort)(BigEndianBitConverter.ToUInt16(tag, 6) & 0x7FFF);
tmp[0] = 0x00;
tmp[1] = tag[8];
tmp[2] = tag[9];
tmp[3] = tag[10];
pmTag.absPage = BigEndianBitConverter.ToUInt32(tmp, 0);
pmTag.checksum = tag[11];
pmTag.relPage = BigEndianBitConverter.ToUInt16(tag, 12);
tmp[0] = 0x00;
tmp[1] = tag[14];
tmp[2] = tag[15];
tmp[3] = tag[16];
pmTag.nextBlock = BigEndianBitConverter.ToUInt32(tmp, 0);
tmp[0] = 0x00;
tmp[1] = tag[17];
tmp[2] = tag[18];
tmp[3] = tag[19];
pmTag.prevBlock = BigEndianBitConverter.ToUInt32(tmp, 0);
pmTag.diskSize = BigEndianBitConverter.ToUInt32(tag, 20);
pmTag.isLast = pmTag.nextBlock == 0xFFFFFF;
pmTag.isFirst = pmTag.prevBlock == 0xFFFFFF;
return pmTag;
}
public static PriamTag? DecodeTag(byte[] tag)
{
if(tag == null)
return null;
PriamTag pmTag = new PriamTag();
switch(tag.Length)
{
case 12:
SonyTag? snTag = DecodeSonyTag(tag);
if(snTag == null)
return null;
pmTag = new PriamTag();
pmTag.absPage = 0;
pmTag.checksum = 0;
pmTag.diskSize = 0;
pmTag.fileID = snTag.Value.fileID;
pmTag.kind = snTag.Value.kind;
pmTag.nextBlock = snTag.Value.nextBlock;
pmTag.prevBlock = snTag.Value.prevBlock;
pmTag.relPage = snTag.Value.relPage;
pmTag.reserved = snTag.Value.reserved;
pmTag.usedBytes = 0;
pmTag.validChk = false;
pmTag.version = snTag.Value.version;
pmTag.volume = snTag.Value.volume;
pmTag.isFirst = snTag.Value.isFirst;
pmTag.isLast = snTag.Value.isLast;
return pmTag;
case 20:
ProfileTag? phTag = DecodeProfileTag(tag);
if(phTag == null)
return null;
pmTag = new PriamTag();
pmTag.absPage = phTag.Value.absPage;
pmTag.checksum = phTag.Value.checksum;
pmTag.diskSize = 0;
pmTag.fileID = phTag.Value.fileID;
pmTag.kind = phTag.Value.kind;
pmTag.nextBlock = phTag.Value.nextBlock;
pmTag.prevBlock = phTag.Value.prevBlock;
pmTag.relPage = phTag.Value.relPage;
pmTag.reserved = phTag.Value.reserved;
pmTag.usedBytes = phTag.Value.usedBytes;
pmTag.validChk = phTag.Value.validChk;
pmTag.version = phTag.Value.version;
pmTag.volume = phTag.Value.volume;
pmTag.isFirst = phTag.Value.isFirst;
pmTag.isLast = phTag.Value.isLast;
return pmTag;
case 24:
return DecodePriamTag(tag);
default:
return null;
}
}
}
}

12
DiscImageChef.Filesystems/ChangeLog
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@@ -1,3 +1,15 @@
2016-08-21 Natalia Portillo <claunia@claunia.com>
* Dir.cs:
* File.cs:
* Info.cs:
* Super.cs:
* Xattr.cs:
* Extent.cs:
* Structs.cs:
* DiscImageChef.Filesystems.csproj: Separate Lisa tag decoding
from Lisa filesystem and added Priam tags.
2016-08-18 Natalia Portillo <claunia@claunia.com>
* exFAT.cs:

4
DiscImageChef.Filesystems/DiscImageChef.Filesystems.csproj
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@@ -118,6 +118,10 @@
<Project>{9F213318-5CB8-4066-A757-074489C9F818}</Project>
<Name>DiscImageChef.Metadata</Name>
</ProjectReference>
<ProjectReference Include="..\DiscImageChef.Decoders\DiscImageChef.Decoders.csproj">
<Project>{0BEB3088-B634-4289-AE17-CDF2D25D00D5}</Project>
<Name>DiscImageChef.Decoders</Name>
</ProjectReference>
</ItemGroup>
<ItemGroup>
<Folder Include="LisaFS\" />

9
DiscImageChef.Filesystems/LisaFS/Dir.cs
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@@ -33,6 +33,7 @@
using System;
using System.Collections.Generic;
using DiscImageChef.ImagePlugins;
using DiscImageChef.Decoders;
namespace DiscImageChef.Filesystems.LisaFS
{
@@ -174,10 +175,10 @@ namespace DiscImageChef.Filesystems.LisaFS
// If root catalog is not pointed in MDDF (unchecked) maybe it's always following S-Records File?
for(ulong i = 0; i < device.GetSectors(); i++)
{
Tag catTag;
LisaTag.PriamTag catTag;
DecodeTag(device.ReadSectorTag(i, SectorTagType.AppleSectorTag), out catTag);
if(catTag.fileID == FILEID_CATALOG && catTag.relBlock == 0)
if(catTag.fileID == FILEID_CATALOG && catTag.relPage == 0)
{
firstCatalogBlock = device.ReadSectors(i, 4);
break;
@@ -194,7 +195,7 @@ namespace DiscImageChef.Filesystems.LisaFS
// Traverse double-linked list until first catalog block
while(prevCatalogPointer != 0xFFFFFFFF)
{
Tag prevTag;
LisaTag.PriamTag prevTag;
DecodeTag(device.ReadSectorTag(prevCatalogPointer + mddf.mddf_block + volumePrefix, SectorTagType.AppleSectorTag), out prevTag);
if(prevTag.fileID != FILEID_CATALOG)
@@ -213,7 +214,7 @@ namespace DiscImageChef.Filesystems.LisaFS
// Traverse double-linked list to read full catalog
while(nextCatalogPointer != 0xFFFFFFFF)
{
Tag nextTag;
LisaTag.PriamTag nextTag;
DecodeTag(device.ReadSectorTag(nextCatalogPointer + mddf.mddf_block + volumePrefix, SectorTagType.AppleSectorTag), out nextTag);
if(nextTag.fileID != FILEID_CATALOG)

3
DiscImageChef.Filesystems/LisaFS/Extent.cs
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@@ -33,6 +33,7 @@
using System;
using DiscImageChef.Console;
using DiscImageChef.ImagePlugins;
using DiscImageChef.Decoders;
namespace DiscImageChef.Filesystems.LisaFS
{
@@ -76,7 +77,7 @@ namespace DiscImageChef.Filesystems.LisaFS
// Pointers are relative to MDDF
ptr += mddf.mddf_block + volumePrefix;
Tag extTag;
LisaTag.PriamTag extTag;
// This happens on some disks.
// This is a filesystem corruption that makes LisaOS crash on scavenge.

7
DiscImageChef.Filesystems/LisaFS/File.cs
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@@ -33,6 +33,7 @@
using System;
using DiscImageChef.ImagePlugins;
using DiscImageChef.Console;
using DiscImageChef.Decoders;
namespace DiscImageChef.Filesystems.LisaFS
{
@@ -212,7 +213,7 @@ namespace DiscImageChef.Filesystems.LisaFS
}
}
Tag sysTag;
LisaTag.PriamTag sysTag;
// Should be enough to check 100 sectors?
for(ulong i = 0; i < 100; i++)
@@ -247,9 +248,9 @@ namespace DiscImageChef.Filesystems.LisaFS
// Relative block for $Loader starts at $Boot block
if(sysTag.fileID == FILEID_LOADER_SIGNED)
sysTag.relBlock--;
sysTag.relPage--;
Array.Copy(sector, 0, buf, sector.Length * sysTag.relBlock, sector.Length);
Array.Copy(sector, 0, buf, sector.Length * sysTag.relPage, sector.Length);
}
}

5
DiscImageChef.Filesystems/LisaFS/Info.cs
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@@ -33,6 +33,7 @@
using System;
using System.Text;
using DiscImageChef.Console;
using DiscImageChef.Decoders;
using DiscImageChef.ImagePlugins;
namespace DiscImageChef.Filesystems.LisaFS
@@ -61,7 +62,7 @@ namespace DiscImageChef.Filesystems.LisaFS
// LisaOS searches sectors until tag tells MDDF resides there, so we'll search 100 sectors
for(int i = 0; i < 100; i++)
{
Tag searchTag;
LisaTag.PriamTag searchTag;
DecodeTag(imagePlugin.ReadSectorTag((ulong)i, SectorTagType.AppleSectorTag), out searchTag);
DicConsole.DebugWriteLine("LisaFS plugin", "Sector {0}, file ID 0x{1:X4}", i, searchTag.fileID);
@@ -150,7 +151,7 @@ namespace DiscImageChef.Filesystems.LisaFS
// LisaOS searches sectors until tag tells MDDF resides there, so we'll search 100 sectors
for(int i = 0; i < 100; i++)
{
Tag searchTag;
LisaTag.PriamTag searchTag;
DecodeTag(imagePlugin.ReadSectorTag((ulong)i, SectorTagType.AppleSectorTag), out searchTag);
DicConsole.DebugWriteLine("LisaFS plugin", "Sector {0}, file ID 0x{1:X4}", i, searchTag.fileID);

42
DiscImageChef.Filesystems/LisaFS/Structs.cs
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@@ -207,48 +207,6 @@ namespace DiscImageChef.Filesystems.LisaFS
public byte scavenge_flag;
}
/// <summary>
/// The sector tag. Before the sector is encoded to GCR the tag is attached to the data.
/// Its size and format varies depending on device.
/// Lisa OS relies on tags for scavenging a floppy, but ignores most of them for normal usage,
/// except on hard disks where the checksum byte is absolutely enforced (a sector with an invalid
/// one gives an OS error).
/// </summary>
struct Tag
{
/// <summary>0x00 version</summary>
public ushort version;
/// <summary>0x02 unknown</summary>
public ushort unknown;
/// <summary>0x04 File ID. Negative numbers are extents for the file with same absolute value number</summary>
public short fileID;
/// <summary>Only in 20 bytes tag at 0x06, mask 0x8000 if valid tag</summary>
public ushort usedBytes;
/// <summary>Only in 20 bytes tag at 0x08, 3 bytes</summary>
public uint absoluteBlock;
/// <summary>Only in 20 bytes tag at 0x0B, checksum byte</summary>
public byte checksum;
/// <summary>0x06 in 12 bytes tag, 0x0C in 20 bytes tag, relative block</summary>
public ushort relBlock;
/// <summary>
/// Next block for this file.
/// In 12 bytes tag at 0x08, 2 bytes, 0x8000 bit seems always set, 0x07FF means this is last block.
/// In 20 bytes tag at 0x0E, 3 bytes, 0xFFFFFF means this is last block.
/// </summary>
public uint nextBlock;
/// <summary>
/// Previous block for this file.
/// In 12 bytes tag at 0x0A, 2 bytes, 0x07FF means this is first block.
/// In 20 bytes tag at 0x11, 3 bytes, 0xFFFFFF means this is first block.
/// </summary>
public uint prevBlock;
/// <summary>On-memory value for easy first block search.</summary>
public bool isFirst;
/// <summary>On-memory value for easy last block search.</summary>
public bool isLast;
}
/// <summary>
/// An entry in the catalog from V3.
/// The first entry is bigger than the rest, may be a header, I have not needed any of its values so I just ignored it.

3
DiscImageChef.Filesystems/LisaFS/Super.cs
View File

@@ -34,6 +34,7 @@ using System;
using System.Collections.Generic;
using DiscImageChef.Console;
using DiscImageChef.ImagePlugins;
using DiscImageChef.Decoders;
namespace DiscImageChef.Filesystems.LisaFS
{
@@ -80,7 +81,7 @@ namespace DiscImageChef.Filesystems.LisaFS
// LisaOS searches sectors until tag tells MDDF resides there, so we'll search 100 sectors
for(ulong i = 0; i < 100; i++)
{
Tag searchTag;
LisaTag.PriamTag searchTag;
DecodeTag(device.ReadSectorTag(i, SectorTagType.AppleSectorTag), out searchTag);
DicConsole.DebugWriteLine("LisaFS plugin", "Sector {0}, file ID 0x{1:X4}", i, searchTag.fileID);

45
DiscImageChef.Filesystems/LisaFS/Xattr.cs
View File

@@ -34,6 +34,7 @@
using System;
using System.Collections.Generic;
using System.Text;
using DiscImageChef.Decoders;
namespace DiscImageChef.Filesystems.LisaFS
{
@@ -214,47 +215,15 @@ namespace DiscImageChef.Filesystems.LisaFS
/// <returns>Error number.</returns>
/// <param name="tag">Sector tag.</param>
/// <param name="decoded">Decoded sector tag.</param>
Errno DecodeTag(byte[] tag, out Tag decoded)
Errno DecodeTag(byte[] tag, out LisaTag.PriamTag decoded)
{
decoded = new Tag();
decoded = new LisaTag.PriamTag();
LisaTag.PriamTag? pmTag = LisaTag.DecodeTag(tag);
if(tag.Length == 12)
{
decoded.version = BigEndianBitConverter.ToUInt16(tag, 0x00);
decoded.unknown = BigEndianBitConverter.ToUInt16(tag, 0x02);
decoded.fileID = BigEndianBitConverter.ToInt16(tag, 0x04);
decoded.relBlock = BigEndianBitConverter.ToUInt16(tag, 0x06);
decoded.nextBlock = BigEndianBitConverter.ToUInt16(tag, 0x08);
decoded.nextBlock &= 0x7FF;
decoded.prevBlock = BigEndianBitConverter.ToUInt16(tag, 0x0A);
decoded.prevBlock &= 0x7FF;
if(decoded.nextBlock == 0x7FF)
decoded.isLast = true;
if(decoded.prevBlock == 0x7FF)
decoded.isFirst = true;
}
else
{
decoded.version = BigEndianBitConverter.ToUInt16(tag, 0x00);
decoded.unknown = BigEndianBitConverter.ToUInt16(tag, 0x02);
decoded.fileID = BigEndianBitConverter.ToInt16(tag, 0x04);
decoded.usedBytes = BigEndianBitConverter.ToUInt16(tag, 0x06);
decoded.absoluteBlock = BigEndianBitConverter.ToUInt32(tag, 0x07);
decoded.absoluteBlock &= 0xFFFFFF;
decoded.checksum = tag[0x0B];
decoded.relBlock = BigEndianBitConverter.ToUInt16(tag, 0x0C);
decoded.nextBlock = BigEndianBitConverter.ToUInt32(tag, 0x0D);
decoded.nextBlock &= 0xFFFFFF;
decoded.prevBlock = BigEndianBitConverter.ToUInt32(tag, 0x10);
decoded.prevBlock &= 0xFFFFFF;
if(decoded.nextBlock == 0xFFFFFF)
decoded.isLast = true;
if(decoded.prevBlock == 0xFFFFFF)
decoded.isFirst = true;
}
if(!pmTag.HasValue)
return Errno.InvalidArgument;
decoded = pmTag.Value;
return Errno.NoError;
}
}