/// <summary>
/// Allocates a decompressor for each cab and merges any cabs that need merged.
/// </summary>
/// <param name="cabinets"></param>
/// <returns></returns>
private static IEnumerable <MSCabinet> MergeCabs(IList <CabInfo> cabInfos)
{
/* Sometimes cab files are part of a set. We must merge those into their set before we leave here.
* Otherwise extracting a file that extends beyond the bounds of one cab in the set will fail. This happens in VBRuntime.msi
*
* It can be determined if a cabinet has further parts to load by examining the mscabd_cabinet::flags field:
* if (flags & MSCAB_HDR_PREVCAB) is non-zero, there is a predecessor cabinet to open() and prepend(). Its MS-DOS case-insensitive filename is mscabd_cabinet::prevname
* if (flags & MSCAB_HDR_NEXTCAB) is non-zero, there is a successor cabinet to open() and append(). Its MS-DOS case-insensitive filename is mscabd_cabinet::nextname
*/
var decompressors = new List <MSCabinet>();
for (int i = 0; i < cabInfos.Count; i++)
{
CabInfo cab = cabInfos[i];
MSCabinet msCab = null;
try
{
msCab = new MSCabinet(cab.LocalCabFile); // NOTE: Deliberately not disposing. Caller must cleanup.
}
catch (Exception)
{
// As seen in https://github.com/activescott/lessmsi/issues/104, sometimes bogus cabs are inside of a msi but they're not needed to extract any files from. So we should attempt to ignore this failure here:
Debug.Fail(
string.Format("Cab name \"{0}\" could not be read by cab reader. Will attempt to ignore...", cab.CabSourceName)
);
continue;
}
if ((msCab.Flags & MSCabinetFlags.MSCAB_HDR_NEXTCAB) != 0)
{
Debug.Assert(!string.IsNullOrEmpty(msCab.NextName), "Header indcates next cab but new cab not found.");
// load the cab found in NextName:
// Append it to msCab
Debug.Print("Found cabinet set. Nextname: " + msCab.NextName);
var nextCab = FindCabAndRemoveFromList(cabInfos, msCab.NextName);
var msCabNext = new MSCabinet(nextCab.LocalCabFile);
msCab.Append(msCabNext);
decompressors.Add(msCab);
}
else if ((msCab.Flags & MSCabinetFlags.MSCAB_HDR_PREVCAB) != 0)
{
Debug.Assert(!string.IsNullOrEmpty(msCab.PrevName), "Header indcates prev cab but new cab not found.");
Debug.Print("Found cabinet set. PrevName: " + msCab.PrevName);
var prevCabInfo = FindCabAndRemoveFromList(cabInfos, msCab.PrevName);
var msCabPrev = new MSCabinet(prevCabInfo.LocalCabFile);
msCabPrev.Append(msCab);
decompressors.Add(msCabPrev);
}
else
{ // just a simple standalone cab
decompressors.Add(msCab);
}
}
return(decompressors);
}
public void CabinetSet()
{
//NO WORKY!
var root = Path.Combine(AppPath, "cabinetset");
var cabFilename1 = Path.Combine(root, "Disk1.CAB");
var cabFilename2 = Path.Combine(root, "Disk2.CAB");
using (var cab1 = new MSCabinet(cabFilename1))
using (var cab2 = new MSCabinet(cabFilename2))
{
cab1.Append(cab2);
ExplodeCab(cab1, OutDir(cabFilename1));
}
Console.ReadLine();
}
public void CabinetSet()
{
string root = Path.Combine(AppContext.BaseDirectory, "test_files", "cabinetset");
string cabFilename1 = Path.Combine(root, "Disk1.CAB");
string cabFilename2 = Path.Combine(root, "Disk2.CAB");
Assert.True(File.Exists(cabFilename1));
Assert.True(File.Exists(cabFilename2));
using (var cab1 = new MSCabinet(cabFilename1))
using (var cab2 = new MSCabinet(cabFilename2))
{
cab1.Append(cab2);
ExplodeCab(cab1, OutDir(cabFilename1));
}
}
/// <summary>
/// Allocates a decompressor for each cab and merges any cabs that need merged.
/// </summary>
/// <param name="cabinets"></param>
/// <returns></returns>
private static IEnumerable <MSCabinet> MergeCabs(IList <CabInfo> cabInfos)
{
/* Sometimes cab files are part of a set. We must merge those into their set before we leave here.
* Otherwise extracting a file that extends beyond the bounds of one cab in the set will fail. This happens in VBRuntime.msi
*
* It can be determined if a cabinet has further parts to load by examining the mscabd_cabinet::flags field:
* if (flags & MSCAB_HDR_PREVCAB) is non-zero, there is a predecessor cabinet to open() and prepend(). Its MS-DOS case-insensitive filename is mscabd_cabinet::prevname
* if (flags & MSCAB_HDR_NEXTCAB) is non-zero, there is a successor cabinet to open() and append(). Its MS-DOS case-insensitive filename is mscabd_cabinet::nextname
*/
var decompressors = new List <MSCabinet>();
for (int i = 0; i < cabInfos.Count; i++)
{
CabInfo cab = cabInfos[i];
var msCab = new MSCabinet(cab.LocalCabFile); //NOTE: Deliberately not disposing. Caller must cleanup.
if ((msCab.Flags & MSCabinetFlags.MSCAB_HDR_NEXTCAB) != 0)
{
Debug.Assert(!string.IsNullOrEmpty(msCab.NextName), "Header indcates next cab but new cab not found.");
// load the cab found in NextName:
// Append it to msCab
Debug.Print("Found cabinet set. Nextname: " + msCab.NextName);
var nextCab = FindCabAndRemoveFromList(cabInfos, msCab.NextName);
var msCabNext = new MSCabinet(nextCab.LocalCabFile);
msCab.Append(msCabNext);
decompressors.Add(msCab);
}
else if ((msCab.Flags & MSCabinetFlags.MSCAB_HDR_PREVCAB) != 0)
{
Debug.Assert(!string.IsNullOrEmpty(msCab.PrevName), "Header indcates prev cab but new cab not found.");
Debug.Print("Found cabinet set. PrevName: " + msCab.PrevName);
var prevCabInfo = FindCabAndRemoveFromList(cabInfos, msCab.PrevName);
var msCabPrev = new MSCabinet(prevCabInfo.LocalCabFile);
msCabPrev.Append(msCab);
decompressors.Add(msCabPrev);
}
else
{ // just a simple standalone cab
decompressors.Add(msCab);
}
}
return(decompressors);
}
static void Main()
{
IEnumerable <string> files = Directory.GetFiles(AppPath, "*.cab");
foreach (var f in files)
{
ExplodeCab(f);
}
//NO WORKY!
var root = Path.Combine(AppPath, "cabinetset");
var cabFilename1 = Path.Combine(root, "Disk1.CAB");
var cabFilename2 = Path.Combine(root, "Disk2.CAB");
using (var cab1 = new MSCabinet(cabFilename1))
using (var cab2 = new MSCabinet(cabFilename2))
{
cab1.Append(cab2);
ExplodeCab(cab1, OutDir(cabFilename1));
}
Console.ReadLine();
}
/// <summary>
/// Allocates a decompressor for each cab and merges any cabs that need merged.
/// </summary>
/// <param name="cabinets"></param>
/// <returns></returns>
private static IEnumerable<MSCabinet> MergeCabs(IList<CabInfo> cabInfos)
{
/* Sometimes cab files are part of a set. We must merge those into their set before we leave here.
* Otherwise extracting a file that extends beyond the bounds of one cab in the set will fail. This happens in VBRuntime.msi
*
* It can be determined if a cabinet has further parts to load by examining the mscabd_cabinet::flags field:
* if (flags & MSCAB_HDR_PREVCAB) is non-zero, there is a predecessor cabinet to open() and prepend(). Its MS-DOS case-insensitive filename is mscabd_cabinet::prevname
* if (flags & MSCAB_HDR_NEXTCAB) is non-zero, there is a successor cabinet to open() and append(). Its MS-DOS case-insensitive filename is mscabd_cabinet::nextname
*/
var decompressors = new List<MSCabinet>();
for (int i=0; i < cabInfos.Count; i++)
{
CabInfo cab = cabInfos[i];
var msCab = new MSCabinet(cab.LocalCabFile);//NOTE: Deliberately not disposing. Caller must cleanup.
if ((msCab.Flags & MSCabinetFlags.MSCAB_HDR_NEXTCAB) != 0)
{
Debug.Assert(!string.IsNullOrEmpty(msCab.NextName), "Header indcates next cab but new cab not found.");
// load the cab found in NextName:
// Append it to msCab
Debug.Print("Found cabinet set. Nextname: " + msCab.NextName);
var nextCab = FindCabAndRemoveFromList(cabInfos, msCab.NextName);
var msCabNext = new MSCabinet(nextCab.LocalCabFile);
msCab.Append(msCabNext);
decompressors.Add(msCab);
}
else if ((msCab.Flags & MSCabinetFlags.MSCAB_HDR_PREVCAB) != 0)
{
Debug.Assert(!string.IsNullOrEmpty(msCab.PrevName), "Header indcates prev cab but new cab not found.");
Debug.Print("Found cabinet set. PrevName: " + msCab.PrevName);
var prevCabInfo = FindCabAndRemoveFromList(cabInfos, msCab.PrevName);
var msCabPrev = new MSCabinet(prevCabInfo.LocalCabFile);
msCabPrev.Append(msCab);
decompressors.Add(msCabPrev);
}
else
{ // just a simple standalone cab
decompressors.Add(msCab);
}
}
return decompressors;
}
