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#10 tap2mbhdd breaks the image

1.0
accepted
nobody
tap2mbhdd (1)
2019-10-17
2019-10-15
z00m128
No

When you try to add a tap file which contains headerless blocks, it breaks the image (produces cross chained sectors).

Discussion

  • z00m128

    z00m128 - 2019-10-15

    And the same is with tap2mbd.

     
  • z00m128

    z00m128 - 2019-10-15

    We analyzed it a bit with Busy, and here are findings:

    1. wrong handling of 0 bytes sized (empty) blocks when present in TAP file, produces wrong dir entry.
    2. if "fake" header exists before headerless block, the size for the headerless block is set from that "fake" header, not from its real size. If block size in that "fake" header doesn't match with following headerless block size, it will break the image.
     
  • Michal Jurica

    Michal Jurica - 2019-10-16
    • status: open --> accepted
     
  • Michal Jurica

    Michal Jurica - 2019-10-16

    It should be fixed. Please, test it.

     
  • z00m128

    z00m128 - 2019-10-17

    Its much better now, but empty block still causes MBD inconsistency. Try the attached TAP, then check resulted MBD with mbdcheck. I suggest throwing those empty blocks away. They are useles anyway.

     

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