How can I use GetVolumeInformation in Inno Setup? - winapi

Question

I need to get the volume serial number for a drive letter during an installation created with Inno Setup. I know that DLL functions can be imported into Inno, but I'm fairly new to it and having some problems getting it to work. I know that the GetVolumeInformation function in kernel32 can do what I need. Could someone show me how to import and use that functionality in an Inno script to retrieve the volume serial number?
Thanks!

Answer 1

Inno-Setup code::
[Code]
function GetVolumeInformation(
lpRootPathName: PChar;
lpVolumeNameBuffer: PChar;
nVolumeNameSize: DWORD;
var lpVolumeSerialNumber: DWORD;
var lpMaximumComponentLength: DWORD;
var lpFileSystemFlags: DWORD;
lpFileSystemNameBuffer: PChar;
nFileSystemNameSize: DWORD
): BOOL;
external 'GetVolumeInformationA#kernel32.dll stdcall';
function LoWord(dw: DWORD): WORD;
begin
Result := WORD(dw);
end;
function HiWord(dw: DWORD): WORD;
begin
Result := WORD((dw shr 16) and $FFFF);
end;
function WordToHex(w: WORD): string;
begin
Result := Format('%.4x', [w]);
end;
function FindVolumeSerial(const Drive: string): string;
var
FileSystemFlags: DWORD;
VolumeSerialNumber: DWORD;
MaximumComponentLength: DWORD;
begin
Result := '';
// Note on passing PChars using RemObjects Pascal Script:
// '' pass a nil PChar
// #0 pass an empty PChar
if GetVolumeInformation(
PChar(Drive),
'', // nil
0,
VolumeSerialNumber,
MaximumComponentLength,
FileSystemFlags,
'', // nil
0)
then
Result := WordToHex(HiWord(VolumeSerialNumber)) + '-' + WordToHex(LoWord(VolumeSerialNumber));
end;
function InitializeSetup(): Boolean;
begin
MsgBox(FindVolumeSerial('c:\'), mbInformation, mb_Ok);
end;
Tested with Inno-setup version 5.2.3
In Unicode versions of Inno-Setup replace PChar with PAnsiChar

Answer 2

Since the InnoSetup doesn't support pointers you will have to create the external library for the call of the GetVolumeInformation function. The following code samples should work for all combinations of the Delphi and InnoSetup (from the Unicode support point of view).
Here's the Delphi library code:
library VolumeInformation;
uses
Types, Classes, SysUtils, Windows;
var
SerialNumber: AnsiString;
function GetVolumeSerial(Drive: PAnsiChar): PAnsiChar; stdcall;
var
FileSystemFlags: DWORD;
VolumeSerialNumber: DWORD;
MaximumComponentLength: DWORD;
begin
SerialNumber := '';
GetVolumeInformationA(Drive, nil, 0, #VolumeSerialNumber,
MaximumComponentLength, FileSystemFlags, nil, 0);
SerialNumber := IntToHex(HiWord(VolumeSerialNumber), 4) + ' - ' +
IntToHex(LoWord(VolumeSerialNumber), 4);
Result := PAnsiChar(SerialNumber);
end;
exports
GetVolumeSerial;
end.
And here's the InnoSetup code:
[Files]
Source: "VolumeInformation.dll"; Flags: dontcopy
[Code]
function GetVolumeSerial(Drive: PAnsiChar): PAnsiChar;
external 'GetVolumeSerial#files:VolumeInformation.dll stdcall setuponly';
procedure ButtonOnClick(Sender: TObject);
var
S: string;
begin
S := GetVolumeSerial('c:\');
MsgBox(S, mbInformation, mb_Ok);
end;