Reading a .CAB file

[paddoswam]

Hi r33d3r,

I've been desperately searching for something to have 1 file which sort of acts like a folder but is encoded or just not easy to access..

I've heard of there terms ".CAB files" and ".PK3 files" PK3 is from PakScape which works just fine for me but then.. how can I access these files?

[dglienna]

Not too difficult.

Expand mycab.cab
MakeCab mycab.cab

[paddoswam]

Not too difficult.

Expand mycab.cab
MakeCab mycab.cab

Euh? That looks to simple, could you explain what it does

[dglienna]

Easy, if you know where to look, like most other things.

Microsoft (R) File Expansion Utility Version 5.1.2600.0
Copyright (C) Microsoft Corp 1990-1999. All rights reserved.

Expands one or more compressed files.
EXPAND [-r] Source Destination
EXPAND -r Source [Destination]
EXPAND -D Source.cab [-F:Files]
EXPAND Source.cab -F:Files Destination

-r Rename expanded files.
-D Display list of files in source.
Source Source file specification. Wildcards may be used.
-F:Files Name of files to expand from a .CAB.
Destination Destination file | path specification.
Destination may be a directory.
If Source is multiple files and -r is not specified,
Destination must be a directory.


Microsoft (R) Cabinet Maker - Version 5.1.2600.2180
Copyright (c) Microsoft Corporation. All rights reserved..

MAKECAB [/V[n]] [/D var=value ...] [/L dir] source [destination]
MAKECAB [/V[n]] [/D var=value ...] /F directive_file [...]

source File to compress.
destination File name to give compressed file. If omitted, the
last character of the source file name is replaced
with an underscore (_) and used as the destination.
/F directives A file with MakeCAB directives (may be repeated).
/D var=value Defines variable with specified value.
/L dir Location to place destination (default is current directory).
/V[n] Verbosity level (1..3).

[paddoswam]

This still doesn't explains how to open a CAB file in VB6 and how to read the files within them...

[paddoswam]

Retry,

I have this .CAB file right? I want to read it from a VB6 app. but I don't want the user to see it on his disk extracted (that's what I did before with a .ZIP file :P) I know it can be done but I really can find it anywhere how to..

[dglienna]

You can display a list of the files, and pipe them into a text file, which you can open in vb, or you can extract individual files from a cab file from within vb, and then delete them. They will still be in the cab file for the next time. You can rename them to whatever you like, and still open them from within your app.

[HackerVlad]

This still doesn't explains how to open a CAB file in VB6 and how to read the files within them...

You can use my module.

https://www.vbforums.com/showthread....g-CAB-archives

Option Explicit
'////////////////////////////////////////////////////////////////////
'// Module for reading and unpacking CAB archives                  //
'// Copyright (c) 2025-02-20 by HackerVlad                         //
'// e-mail: [email protected]                                 //
'// Version 2.5 (32 and 64-bit compatible) & Windows 98 compatible //
'////////////////////////////////////////////////////////////////////

' API declarations ...
#If VBA7 = 0 Then
Private Declare Function SetupIterateCabinetW Lib "setupapi" (ByVal CabinetFile As Long, ByVal Reserved As Long, ByVal MsgHandler As Long, ByVal Context As Long) As Long
Private Declare Function SetupIterateCabinetA Lib "setupapi" (ByVal CabinetFile As String, ByVal Reserved As Long, ByVal MsgHandler As Long, ByVal Context As Long) As Long
Private Declare Function PathRemoveFileSpecW Lib "shlwapi" (ByVal pszPath As Long) As Long
Private Declare Function SHCreateDirectory Lib "shell32" (ByVal hwnd As Long, ByVal pszPath As Long) As Long
Private Declare Function MakeSureDirectoryPathExists Lib "imagehlp" (ByVal lpPath As String) As Long ' For old versions of Windows
Private Declare Function SysReAllocString Lib "oleaut32" (ByVal pBSTR As Long, ByVal psz As Long) As Long
Private Declare Sub SysFreeString Lib "oleaut32" (ByVal bstr As Long)
Private Declare Function GetFileAttributesEx Lib "kernel32" Alias "GetFileAttributesExW" (ByVal lpFileName As Long, ByVal fInfoLevelId As Long, ByRef lpFileInformation As Any) As Long
Private Declare Function lstrlenA Lib "kernel32" (ByVal lpString As Long) As Long
Private Declare Function SetFileAttributesW Lib "kernel32" (ByVal lpFileName As Long, ByVal dwFileAttributes As Long) As Long
Private Declare Function SetFileAttributesA Lib "kernel32" (ByVal lpFileName As Long, ByVal dwFileAttributes As Long) As Long
Private Declare Function GetVersionEx Lib "kernel32" Alias "GetVersionExA" (lpVersionInformation As Any) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Private Declare Sub ZeroMemory Lib "kernel32" Alias "RtlZeroMemory" (Destination As Any, ByVal Length As Long)

Private Enum LongPtr
    [_]
End Enum
#Else
Private Declare PtrSafe Function SetupIterateCabinetW Lib "setupapi" (ByVal CabinetFile As LongPtr, ByVal Reserved As Long, ByVal MsgHandler As LongPtr, ByVal Context As Long) As Long
Private Declare PtrSafe Function SetupIterateCabinetA Lib "setupapi" (ByVal CabinetFile As String, ByVal Reserved As Long, ByVal MsgHandler As LongPtr, ByVal Context As Long) As Long
Private Declare PtrSafe Function PathRemoveFileSpecW Lib "shlwapi" (ByVal pszPath As LongPtr) As Long
Private Declare PtrSafe Function SHCreateDirectory Lib "shell32" (ByVal hwnd As Long, ByVal pszPath As LongPtr) As Long
Private Declare PtrSafe Function MakeSureDirectoryPathExists Lib "imagehlp" (ByVal lpPath As String) As Long ' For old versions of Windows
Private Declare PtrSafe Function SysReAllocString Lib "oleaut32" (ByVal pBSTR As LongPtr, ByVal psz As LongPtr) As Long
Private Declare PtrSafe Sub SysFreeString Lib "oleaut32" (ByVal bstr As LongPtr)
Private Declare PtrSafe Function GetFileAttributesEx Lib "kernel32" Alias "GetFileAttributesExW" (ByVal lpFileName As LongPtr, ByVal fInfoLevelId As Long, ByRef lpFileInformation As Any) As Long
Private Declare PtrSafe Function lstrlenA Lib "kernel32" (ByVal lpString As LongPtr) As Long
Private Declare PtrSafe Function SetFileAttributesW Lib "kernel32" (ByVal lpFileName As LongPtr, ByVal dwFileAttributes As Long) As Long
Private Declare PtrSafe Function SetFileAttributesA Lib "kernel32" (ByVal lpFileName As String, ByVal dwFileAttributes As Long) As Long
Private Declare PtrSafe Function GetVersionEx Lib "kernel32" Alias "GetVersionExA" (lpVersionInformation As Any) As Long
Private Declare PtrSafe Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Private Declare PtrSafe Sub ZeroMemory Lib "kernel32" Alias "RtlZeroMemory" (Destination As Any, ByVal Length As Long)
#End If

' Constants ...
Private Const MAXPATH = 260
Private Const FILEOP_DOIT = 1
Private Const FILEOP_SKIP = 2
Private Const SPFILENOTIFY_FILEINCABINET = &H11
Private Const SPFILENOTIFY_FILEEXTRACTED = &H13
Private Const GetFileExInfoStandard As Long = 0

' Own fictional constants ...
Private Const sicList = 568
Private Const sicCount = 569
Private Const sicExtract = 570

' Variables for temporary data storage ...
Dim CountFilesSuccessfullyExtracted As Long, SetAttribsFile As Long, lngCount As Long
Dim strFileToExtract As String, strOutputPath As String
Dim arrFilesToExtract() As String
Dim arrListFilesCab() As CabInfo
Dim IsFilesList As Boolean, WinANSI As Boolean

' Structures ...
Public Type CabInfo
    cabFileName As String
    cabFileSize As Long
    cabDosDate As Integer
    cabDosTime As Integer
    cabDosAttribs As Integer
End Type

Private Type FileInCabinetInfoW
    NameInCabinet As LongPtr
    FileSize      As Long
    Win32Error    As Long
    DosDate       As Integer
    DosTime       As Integer
    DosAttribs    As Integer
    FullTargetName(MAXPATH - 1) As Integer ' WCHAR  FullTargetName[MAX_PATH];
End Type

Private Type FILEPATHS
    Target     As LongPtr
    Source     As LongPtr
    Win32Error As Integer
    Flags      As Long
End Type

Private Type WIN32_FILE_ATTRIBUTE_DATA
    dwFileAttributes    As Long
    ftCreationTime      As Currency
    ftLastAccessTime    As Currency
    ftLastWriteTime     As Currency
    nFileSizeHigh       As Long
    nFileSizeLow        As Long
End Type

' Does the directory exist (IsDir)
Public Function cabIsDir(ByVal path As String) As Boolean
    Dim tAttr As WIN32_FILE_ATTRIBUTE_DATA
    
    If GetFileAttributesEx(StrPtr(path), GetFileExInfoStandard, tAttr) <> 0 Then
        If (tAttr.dwFileAttributes And vbDirectory) <> 0 Then
            cabIsDir = True
        End If
    Else ' ANSI
        On Error Resume Next
        If Dir(path, vbDirectory + 7) <> vbNullString Then
            If (GetAttr(path) And vbDirectory) <> 0 Then cabIsDir = True
        End If
    End If
End Function

' Convert the full file path to the folder path (always returns "\" at the end)
Public Function cabExtractFilePath(ByVal FileName As String) As String
    Dim lNullPos As Long
    Dim pszPath As String
    
    pszPath = FileName
    PathRemoveFileSpecW StrPtr(pszPath)
    
    lNullPos = InStr(1, pszPath, vbNullChar)
    If lNullPos Then
        pszPath = Left$(pszPath, lNullPos - 1)
        If Right$(pszPath, 1) <> "\" Then pszPath = pszPath & "\"
        cabExtractFilePath = pszPath
    Else
        cabExtractFilePath = FileName
    End If
End Function

' Create multiple folders at once, for all versions of Windows (always requires a "\" at the end for systems less than WinXP)
Public Function MakeDir(ByVal path As String) As Boolean
    Dim inf(36) As Long
    Dim IsXPAndLater As Boolean
    
    inf(0) = 148: GetVersionEx inf(0): IsXPAndLater = inf(4) = 2 And inf(1) >= 5 And inf(2) >= 1 ' Get the Windows version
    
    If IsXPAndLater = True Then
        If SHCreateDirectory(0, StrPtr(path)) = 0 Then MakeDir = True
    Else
        If MakeSureDirectoryPathExists(path) = 1 Then MakeDir = True
    End If
End Function

Private Function CabinetCallback(ByVal Context As Long, ByVal Notification As Long, Param1 As FileInCabinetInfoW, ByVal Param2 As Long) As Long
    If Notification = SPFILENOTIFY_FILEINCABINET Then
        Dim FileNameInCab As String
        Dim bytesLen As Long
        
        Select Case Context
            Case sicCount
                lngCount = lngCount + 1
                CabinetCallback = FILEOP_SKIP ' Skip the file and go through the list of files next
                
            Case sicList
                If WinANSI = False Then
                    SysReAllocString VarPtr(FileNameInCab), Param1.NameInCabinet
                Else
                    bytesLen = lstrlenA(Param1.NameInCabinet)
                    FileNameInCab = Space$(bytesLen)
                    CopyMemory ByVal FileNameInCab, ByVal Param1.NameInCabinet, bytesLen + 1 ' Converts to Unicode using an implicit (hidden) conversion
                End If
                
                ' Add a position to the UDT array
                ReDim Preserve arrListFilesCab(lngCount)
                arrListFilesCab(lngCount).cabFileName = FileNameInCab
                arrListFilesCab(lngCount).cabFileSize = Param1.FileSize
                arrListFilesCab(lngCount).cabDosDate = Param1.DosDate
                arrListFilesCab(lngCount).cabDosTime = Param1.DosTime
                arrListFilesCab(lngCount).cabDosAttribs = Param1.DosAttribs
                
                lngCount = lngCount + 1
                CabinetCallback = FILEOP_SKIP ' Skip the file and go through the list of files next
                If WinANSI = False Then SysFreeString StrPtr(FileNameInCab)
                
            Case sicExtract
                Dim FileName As String, FilePath As String, FillFileName As String
                Dim i As Long
                
                If WinANSI = False Then
                    SysReAllocString VarPtr(FileNameInCab), Param1.NameInCabinet
                Else
                    bytesLen = lstrlenA(Param1.NameInCabinet)
                    FileNameInCab = Space$(bytesLen)
                    CopyMemory ByVal FileNameInCab, ByVal Param1.NameInCabinet, bytesLen + 1 ' Converts to Unicode using an implicit (hidden) conversion
                End If
                FileName = strOutputPath & "\" & FileNameInCab
                
                ' We fill in the value of the structure with the filename of the extracted file (+1 character at the end of the line is vbNullChar)
                If Not WinANSI Then FillFileName = FileName Else FillFileName = StrConv(FileName, vbFromUnicode) ' Convert to ANSI
                If Not WinANSI Then ZeroMemory Param1.FullTargetName(0), 520 Else ZeroMemory Param1.FullTargetName(0), 260
                CopyMemory Param1.FullTargetName(0), ByVal StrPtr(FillFileName), LenB(FillFileName) + 1
                
                If IsFilesList = False Then
                    If strFileToExtract = FileNameInCab Or Len(strFileToExtract) = 0 Then
                        FilePath = cabExtractFilePath(FileName)
                        If cabIsDir(FilePath) = False Then MakeDir FilePath
                        
                        SetAttribsFile = Param1.DosAttribs ' Remember the attributes
                        CabinetCallback = FILEOP_DOIT ' Extract the file
                        CountFilesSuccessfullyExtracted = CountFilesSuccessfullyExtracted + 1
                    Else
                        CabinetCallback = FILEOP_SKIP ' Skip the file and go through the list of files next
                    End If
                Else
                    Dim ExtractCurrentFile As Boolean
                    
                    For i = 0 To UBound(arrFilesToExtract)
                        If arrFilesToExtract(i) = FileNameInCab Then
                            ExtractCurrentFile = True
                            Exit For
                        End If
                    Next
                    
                    If ExtractCurrentFile = True Then
                        FilePath = cabExtractFilePath(FileName)
                        If cabIsDir(FilePath) = False Then MakeDir FilePath
                        
                        SetAttribsFile = Param1.DosAttribs ' Remember the attributes
                        CabinetCallback = FILEOP_DOIT ' Extract the file
                        CountFilesSuccessfullyExtracted = CountFilesSuccessfullyExtracted + 1
                    Else
                        CabinetCallback = FILEOP_SKIP ' Skip the file and go through the list of files next
                    End If
                End If
                
                If WinANSI = False Then SysFreeString StrPtr(FileNameInCab)
        End Select
    ElseIf Notification = SPFILENOTIFY_FILEEXTRACTED Then
        Dim fp As FILEPATHS
        
        LSet fp = Param1
        
        If fp.Win32Error = 0 Then ' If the file has been successfully extracted from the archive
            ' Manually set the attributes of the extracted file yourself,
            ' as Microsoft kindly refused to do this in the SetupIterateCabinet function
            If SetFileAttributesW(fp.Target, SetAttribsFile) = 0 Then
                SetFileAttributesA fp.Target, SetAttribsFile
            End If
        End If
    End If
End Function

' Get a list of files inside the CAB archive
Public Function GetFilesListInCab(ByVal cabFileName As String, arrCabInfo() As CabInfo) As Long
    lngCount = 0
    WinANSI = False
    
    If SetupIterateCabinetW(StrPtr(cabFileName), 0, AddressOf CabinetCallback, sicList) Then
        arrCabInfo = arrListFilesCab
        GetFilesListInCab = lngCount
        Erase arrListFilesCab
    Else
        WinANSI = True
        If SetupIterateCabinetA(cabFileName, 0, AddressOf CabinetCallback, sicList) Then
            arrCabInfo = arrListFilesCab
            GetFilesListInCab = lngCount
            Erase arrListFilesCab
        End If
    End If
End Function

' Get count of files inside the CAB archive
Public Function GetFilesCountInCab(ByVal cabFileName As String) As Long
    lngCount = 0
    
    If SetupIterateCabinetW(StrPtr(cabFileName), 0, AddressOf CabinetCallback, sicCount) Then
        GetFilesCountInCab = lngCount
    Else
        If SetupIterateCabinetA(cabFileName, 0, AddressOf CabinetCallback, sicCount) Then GetFilesCountInCab = lngCount
    End If
End Function

' Extract files from the CAB archive
' Extracting archives compressed using MSZIP works in Windows 95+
' Extracting archives compressed using LZX21 works in Windows Me+
' FileList - an extracted file from an archive (string) if there is one file, or an array of strings if there are several files to extract
' If the FileList parameter is omitted, all files from the archive will be extracted
Public Function ExtractFilesInCab(ByVal cabFileName As String, ByVal ExpandDir As String, Optional FileList As Variant) As Boolean
    If Len(cabFileName) > 0 And Len(ExpandDir) > 0 Then
        If Right$(ExpandDir, 1) = "\" Then
            strOutputPath = Mid$(ExpandDir, 1, Len(ExpandDir) - 1)
        Else
            strOutputPath = ExpandDir
        End If
        
        If cabIsDir(strOutputPath) = False Then
            If MakeDir(strOutputPath) = False Then Exit Function
        End If
        
        If VarType(FileList) = vbString Then
            strFileToExtract = FileList
        ElseIf VarType(FileList) = vbArray + vbString Then ' If it is an array of strings
            strFileToExtract = ""
            arrFilesToExtract = FileList
            IsFilesList = True
        Else
            strFileToExtract = ""
        End If
        
        CountFilesSuccessfullyExtracted = 0
        WinANSI = False
        
        If SetupIterateCabinetW(StrPtr(cabFileName), 0, AddressOf CabinetCallback, sicExtract) Then
            If IsFilesList = False Then
                If CountFilesSuccessfullyExtracted = 1 Or Len(strFileToExtract) = 0 Then ExtractFilesInCab = True
            Else
                If CountFilesSuccessfullyExtracted = UBound(arrFilesToExtract) + 1 Then ExtractFilesInCab = True
            End If
        Else
            WinANSI = True
            If SetupIterateCabinetA(cabFileName, 0, AddressOf CabinetCallback, sicExtract) Then
                If IsFilesList = False Then
                    If CountFilesSuccessfullyExtracted = 1 Or Len(strFileToExtract) = 0 Then ExtractFilesInCab = True
                Else
                    If CountFilesSuccessfullyExtracted = UBound(arrFilesToExtract) + 1 Then ExtractFilesInCab = True
                End If
            End If
        End If
        
        If IsFilesList = True Then
            IsFilesList = False
            Erase arrFilesToExtract
        End If
    End If
End Function