aaru-dps/Aaru
1
0
Fork 0
mirror of https://github.com/aaru-dps/Aaru.git synced 2025-12-16 19:24:25 +00:00
Code Issues Packages Projects Releases Wiki Activity

Separate Lisa tag decoding from Lisa filesystem and added

Browse Source 
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
Download Patch File Download Diff File Expand all files Collapse all files

42
DiscImageChef.Filesystems/LisaFS/Structs.cs
View File

@@ -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.