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我尝试将 sparse.img 解析为 unsparse.img 我已成功获得总块和第一个块，问题是当尝试获取第二个块标头时，这意味着无法获取块标头类型问题是我在哪里获得下一个标头块

我的代码用于获取缓冲区

  Dim hSparseImage = -1
    Dim bSparseImage = False
    Dim openfile = "userdata.img"
    Dim infos As New FileInfo(openfile)
    Dim fileLength = infos.Length
    Dim count = 1048576
    Dim EXT4_CHUNK_HEADER_SIZE = 12
    Dim sparseheader As SPARSE_HEADER
    Dim chunkheader As CHUNK_HEADER
    Dim stream As New FileStream(openfile, FileMode.Open, FileAccess.Read)
    Using reader As New BinaryReader(stream)
        Dim buffer(fileLength) As Byte
        reader.BaseStream.Seek(0, SeekOrigin.Begin)
        reader.Read(buffer, 0, 28)
        sparseheader = parsingheader(buffer)
        Dim magic = sparseheader.dwMagic

        Dim header_magic = (Val("&HE" & Hex(magic)))
        Dim dwChunkSize As Long = 0
        Dim offsetnya As Long = 0
        Dim nextt = 0
        Dim chunkh As Integer
        Dim hexchunktype As Int32
        If header_magic = SPARSE_MAGIC Then
            Dim totalchunk = sparseheader.dwTotalChunks
            If totalchunk > 0 Then
                For i = 0 To totalchunk - 1
                    reader.Read(buffer, 0, 12)
                    chunkheader = parsingchunk(buffer)


                    Dim chunktype = chunkheader.wChunkType
                    hexchunktype = (Val("&HE" & Hex(chunktype)))
                    If hexchunktype = SPARSE_RAW_CHUNK Then
                        dwChunkSize = chunkheader.dwChunkSize * sparseheader.dwBlockSize
                        RichTextBox1.Text += "chunk total size " & chunkheader.dwTotalSize & vbNewLine
                    ElseIf hexchunktype = SPARSE_FILL_CHUNK Then
                        RichTextBox1.Text += "fill" & vbNewLine
                    ElseIf hexchunktype = SPARSE_DONT_CARE Then
                        RichTextBox1.Text += "DoNT care" & vbNewLine
                    Else
                        RichTextBox1.Text += "Invalid data" & vbNewLine
                    End If
                    chunkh = chunkh + chunkheader.dwTotalSize
                    RichTextBox1.Text += i & chunkh & vbNewLine & vbNewLine
                Next
            Else
                RichTextBox1.Text += "Pailit get total chunk"
            End If
        End If

    End Using
    stream.Close()

并用于获取结构并获取缓冲区数组以进行结构

Private Function parsingheader(ByVal bytes As Byte()) As SPARSE_HEADER
    Dim stuff As SPARSE_HEADER
    Dim handle As GCHandle = GCHandle.Alloc(bytes, GCHandleType.Pinned)

    Try
        stuff = CType(Marshal.PtrToStructure(handle.AddrOfPinnedObject(), GetType(SPARSE_HEADER)), SPARSE_HEADER)
    Finally
        handle.Free()
    End Try

    Return stuff
End Function

Private Function parsingchunk(ByVal bytes As Byte()) As CHUNK_HEADER
    Dim stuff As CHUNK_HEADER
    Dim handle As GCHandle = GCHandle.Alloc(bytes, GCHandleType.Pinned)

    Try
        stuff = CType(Marshal.PtrToStructure(handle.AddrOfPinnedObject(), GetType(CHUNK_HEADER)), CHUNK_HEADER)
    Finally
        handle.Free()
    End Try

    Return stuff
End Function

Private Structure SPARSE_HEADER
    Public dwMagic As Int32
    Public wVerMajor As Int16
    Public wVerMinor As Int16
    Public wSparseHeaderSize As Int16
    Public wChunkHeaderSize As Int16
    Public dwBlockSize As Int32
    Public dwTotalBlocks As Int32
    Public dwTotalChunks As Int32
    Public dwImageChecksum As Int32


End Structure
Private Structure CHUNK_HEADER
    Public wChunkType As Int16
    Public wReserved As Int16
    Public dwChunkSize As Int32
    Public dwTotalSize As Int32


End Structur
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