Hi,

When i try to open a VHD archive both7z.exe and 7zFM.exe reports

Unspecified Error

msg. While the same vhd is attaching successfully in windows disk management. What would the cause of this error message?

/Thanks

1) Try different versions of 7-Zip: 9.25 alpha and 9.28 alpha
2) Try to open only top level with command
7z l a.vhd -t*
if it works, extract it:
7z x a.vhd -t*
and then try to open / extract next level:
7z l a.mbr -t*
….
and then try to open NTFS level.

Hi,

I get this error when trying 7z x a.vhd -t*

Extracting  test.mbr     Data Error
Sub items Errors: 1

/Thanks

Hi,
edited:
I get this error when trying 7z x test.vhd -t*

Extracting  test.mbr     Data Error
Sub items Errors: 1

/Thanks

Hi,

HRESULT ReadStream(ISequentialInStream *stream, void *data, size_t *processedSize)
{
  
    HRESULT res = stream->Read(data, curSize, &processedSizeLoc);
    *processedSize += processedSizeLoc;
    
}

When i tried debugging the FM code, res becomes S_FALSE so it fails with this unspecified error. Any clue on how to solve this issue?

/Thanks

Show log.txt:
7z l a.vhd -t* > log.txt

Hi.

7-Zip [64] 9.28 alpha  Copyright (c) 1999-2012 Igor Pavlov  2012-06-20
Listing archive: G:\Error.vhd
--
Path = G:\Error.vhd
Type = VHD
Created = 2012-06-29 08:27:26
Cluster Size = 2097152
Method = Dynamic
Creator Application = win 6.1
Host OS = Windows
Saved State = -
ID = 13FF4FADD36CF64F8330A9A40898950B
   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
                    .....   5368709120    136314880  Error.mbr
------------------- ----- ------------ ------------  ------------------------
                            5368709120    136314880  1 files, 0 folders

7-Zip [64] 9.28 alpha  Copyright (c) 1999-2012 Igor Pavlov  2012-06-20
Processing archive: G:\Error.vhd
Extracting  Error.mbr     Data Error
Sub items Errors: 1

This is the message i  see in log file. For listing and extract command of 7z

What software was used to create that vhd file?

Try to debug the VhdHandler.cpp code with
7z t error.vhd -t* -scrc

Or compress file with password to 7z archive, upload it to some server and send download link to my e-mail.

Hi,

I have mailed you the link to the file. In meantime i will also follow the steps you told.
/Thanks

error in code (return S_FALSE):

      if (((BitMap >> (7 - (bmi & 7))) & 1) == 0)
      {
        if (ParentStream)
        {
          RINOK(ParentStream->Seek(_virtPos + cur, STREAM_SEEK_SET, NULL));
          RINOK(ReadStream_FALSE(ParentStream, (Byte *)data + cur, rem));
        }
        else
        {
          const Byte *p = (const Byte *)data + cur;
          for (UInt32 i = 0; i < rem; i++)
            if (p_ != 0)
              return S_FALSE;
        }

As I understand, file must contain zeros for data that is Zero in bimap.
I suppose that standard MS tool creates such "correct" VHDs.

So, write zeros to your VHD file.
_

const Byte p = (const Byte )data + cur;
          for (UInt32 i = 0; i < rem; i++)
            if (p[i] != 0)
              return S_FALSE;

Hi,

1. Does 7Z fail if we exceed the MAX_PATH limit for path ?
2. How to use 7zG.exe seperately without interface of 7ZFM?

/Thanks

1. 7-zip tries to use long pathes in that case
2. 7zg.exe and 7z.exe support same commands and switches described in 7-zip.chm.

Hi,

I wanted to use 7zG.exe for testing a VHD archive but i would like to make it in slient mode (i.e) I dont want the progress bar to appear what can be done for it to take affect? any help on this.

/Thanks.

Do you need other messages like errors and so on?
Maybe you can call 7z.exe with inactive console window.

Hi,

That sounds good for me. which flag should i use for it? .. thanks.
For information, may i know how does test archive works on VHD?
/Thanks

1. As I remember it's
CREATE_NO_WINDOW
for
CreateProcess function
http://msdn.microsoft.com/en-us/library/windows/desktop/ms684863%28v=vs.85%29.aspx

2. Probably it tests files inside NTFS inside VHD.

Hi,

Is there a way to search files inside the archive in 7Zip?
or How to implement it?

/Thanks

If you need to search some string, you must create new class that implements ISequentialOutStream interface. That implementation must search string in stream.
And in extract callback you must send that ISequentialOutStream implementation instead of implementation that work with files on disk.

Hi,

I have a VHD file say if i compress the blocks of VHD using 7Zip compression algorithm. Will i still be able to open the VHD file using 7ZipFM ?
Any help on this?

/Thanks

I don't understand that question.

Hi,

Say I create a VHD file with 2MB block - before storing it as a in the VHD, I also compress the 2MB block with 7zip. I know it is not possible for the 7zip to read the VHD as it is - but where exactly should I look in the code to make this case of VHD compressed with 7zip to make it work.

/Thanks

1) Why do you need it?
2) What compression method do you want to use?

1) Why do you need it?
> I have developed a application which would create VHD and write data into it. Using 7Zip FM i was able to open the VHD  as an archive. Now i wanted to write data into it in compressed way and still wanted to explorer the contents of the VHD using 7ZipFm . So i thought of compressing the data using 7Zip compression algorithm
2) What compression method do you want to use?
> LZMA or LZMA2

/Thanks

It will be not VHD compatible. So other programs will not be able to open it. So it will be new format.

And probaby it's simpler to write it from zero without using VHD format.

You need some "map" that will contain information for each block:
Compressed size and LZMA properties.
If you need "delete" feature for such archive, you need some smart space allocator, since compressed blocks have different sizes.