GHFix: VB6 GitHub Linebreak Repair
I've been downloading a lot of VB6 projects from GitHub to test in twinBASIC. When these have been uploaded with certain settings, GitHub replaces the vbCrLf line breaks with vbLf only, which results in a corrupt file that VB6 can't read. tB can-- but I need to confirm working in VB6 first. So I made this small project to automatically repair the line breaks of all VB6 files in a given directory, with a number of options to help. The file type list is preset, but you could change it to work on any file type instead.
This project uses my WinDevLib project for all the APIs (this is why the source file size is so large; however the compiled exe uses only what is neccessary, so is only 2MB). Can be compiled to both 32bit and 64bit. I've tested to confirm the output is byte for byte identical to using WinHex to manually replace 0x0A with 0x0D 0x0A, and the app checks whether the line breaks already appear to be correct.
Update v1.2.4 fixes crashing issues relating to handle release (FindClose vs CloseHandle)
Update v1.1.3 fixes the bug where not all files that match the filter are added to the list and processed.
Update v1.0.2 fixes an unhandled error when canceling the choose path dialog.
The basic principle is two loops. First, we count how many Lf's (0x0A) there are while checking if there's already an 0x0D before it:
For j = 0 To UBound(btSrc)
If btSrc(j) = btFind Then
If (nMatch = 0) And (bFlagOk = False) And (j <> 0) Then
If btSrc(j - 1) = btApp Then
Dim r As VbMsgBoxResult = MsgBox("Warning: The current file appears to already have correct line breaks; continue anyway?" & vbCrLf & "Press 'Try again' to skip to the next file, 'Continue' to proceed and suppress future warnings, or 'Cancel' to abort the entire operation.", vbCritical Or vbCancelTryAgainContinue, sName)
If r = vbCancel Then
CloseHandle hFile
Return 1
ElseIf r = vbContinue Then
bFlagOk = True
ElseIf r = vbTryAgain Then
CloseHandle hFile
GoTo NextFile
End If
End If
End If
cbDst += 1
nMatch += 1
End If
NextThis is used to compute the total size we'll need for the repaired file, so we can copy it right in with ease:
ReDim btDst(cbDst - 1)
For j = 0 To UBound(btSrc)
If btSrc(j) = btFind Then
btDst(k) = btApp
btDst(k + 1) = btFind
k += 2
Else
btDst(k) = btSrc(j)
k += 1
End If
NextThen we just make sure the file pointer is at the beginning and save:
lRet = SetFilePointer(hFile, 0, ByVal 0, FILE_BEGIN)
If (lRet = INVALID_SET_FILE_POINTER) Or (Err.LastDllError <> NO_ERROR) Then
PostLog "Failed to reset file pointer on " & sName
CloseHandle hFile
Return 2
End If
lRet = WriteFile(hFile, btDst(0), cbDst, cbRet, vbNullPtr)
If lRet Then
PostLog "Successfully fixed " & nMatch & IIf(nMatch = 1, " line break", " line breaks") & " in " & sName
Else
PostLog "Failed to write output to " & sName & ", " & PrintError(Err.LastDllError)
End If
CloseHandle hFileAnd that's the core of it. The snippets above are just to illustrate technique, there's a lot of missing error checking and other stuff. Download the project or browse Export for the full source.