EbmlNodeMaster ParseTree(EbmlSig element)
{
string err = null;
var contentLenBuf = ReadMTF(Data.fbs, out long contentLen);
if (contentLen < 0)
{
return(null);
}
Data.ValidSize += contentLenBuf.Length;
var newMaster = new EbmlNodeMaster(element, contentLenBuf.Length + contentLen);
var buf = new byte[3];
long stop = Data.ValidSize + contentLen;
while (Data.ValidSize < stop)
{
Data.fbs.Position = Data.ValidSize;
var got = Data.fbs.Read(buf, 0, 3);
if (got < 3)
{
err = "File corrupt or truncated"; goto FATAL;
}
EbmlNode newNode;
foreach (var item in masterSigs)
{
if (item.SigIsStartOf(buf))
{
Data.fbs.Position = Data.ValidSize = Data.ValidSize + item.Signature.Count;
newNode = ParseTree(item);
if (IssueModel.Data.HasFatal)
{
if (newNode != null)
{
newMaster.AddNode(newNode);
}
return(newMaster);
}
goto NEXT;
}
}
foreach (var item in leafSigs)
{
if (item.SigIsStartOf(buf))
{
Data.fbs.Position = Data.ValidSize = Data.ValidSize + item.Signature.Count;
byte[] payload = null;
byte[] payloadHdr = ReadMTF(Data.fbs, out long payloadLen);
if (payloadHdr == null)
{
err = "File truncated or corrupt"; goto FATAL;
}
if ((item.Flag & ParseFlag.Persist) != 0)
{
payload = new byte[payloadLen];
got = Data.fbs.Read(payload, 0, (int)payloadLen);
}
if (buf[0] != CrcSig.Sig32)
{
newNode = new EbmlNodeLeaf(item, payload);
}
else
{
++Data.CrcCount;
long hashStart = Data.ValidSize + payloadHdr.Length + payloadLen;
long hashCount;
if (newMaster.Nodes.Count == 0)
{
hashCount = contentLen - 5 - payloadHdr.Length;
}
else
{
IssueModel.Add("Misplaced CRC");
hashCount = 0;
}
newNode = new EbmlNodeCRC(item, payload, hashStart, hashCount);
}
Data.ValidSize += payloadHdr.Length + payloadLen;
goto NEXT;
}
}
err = $"Unknown element [{buf[0]:X2}][{buf[1]:X2}][{buf[2]:X2}]";
goto FATAL;
NEXT:
newMaster.AddNode(newNode);
}
if (Data.ValidSize == stop)
{
return(newMaster);
}
err = "Positional error";
FATAL:
err += String.Format(" at {0:X}.", Data.ValidSize);
IssueModel.Add(err, Severity.Fatal);
return(newMaster);
}
public Model(Stream stream, string path)
{
base._data = Data = new MkvFormat(this, stream, path);
var bb = new byte[5];
Data.fbs.Position = Data.ValidSize = 4;
Data.root = ParseTree(rootSig);
Data.layout.Add(Data.root);
if (Data.Issues.HasError)
{
return;
}
System.Diagnostics.Debug.Assert(Data.ValidSize == Data.fbs.Position);
Data.fbs.Position = Data.ValidSize;
long SegmentLength = ReadMTF(0x18, 0x53, 0x80, 0x67);
if (SegmentLength < 0)
{
IssueModel.Add("Missing root element.", Severity.Fatal); return;
}
System.Diagnostics.Debug.Assert(Data.ValidSize == Data.fbs.Position);
long segmentStart = Data.ValidSize;
var diff = Data.ValidSize + SegmentLength - Data.FileSize;
if (diff > 0)
{
IssueModel.Add($"File appears truncated by {diff} bytes.", Severity.Error);
}
Data.segment = new EbmlNodeMaster(segmentSig, SegmentLength);
Data.layout.Add(Data.segment);
Data.fbs.Position = Data.ValidSize;
while (Data.ValidSize < segmentStart + SegmentLength)
{
Data.fbs.Position = Data.ValidSize;
int got = Data.fbs.Read(bb, 0, 4);
if (got < 3)
{
break;
}
if (bb[0] == voidSig.Sig32)
{
Data.fbs.Position = Data.ValidSize + 1;
var voidLenBuf = ReadMTF(Data.fbs, out long voidLen);
if (voidLen < 0)
{
IssueModel.Add("File truncated near void.", Severity.Fatal); return;
}
Data.ValidSize += 1 + voidLenBuf.Length + voidLen;
var voidNode = new EbmlNodeLeaf(voidSig, voidLen);
Data.segment.AddNode(voidNode);
continue;
}
if (got < 4)
{
break;
}
foreach (var mstr in topSigs)
{
if (mstr.SigIsStartOf(bb))
{
Data.fbs.Position = Data.ValidSize = Data.ValidSize + 4;
if ((mstr.Flag & ParseFlag.PrunePayload) != 0)
{
var payloadLenBuf = ReadMTF(Data.fbs, out long payloadLen);
if (payloadLen < 0)
{
IssueModel.Add("File corrupt or truncated.", Severity.Fatal); return;
}
Data.ValidSize += payloadLenBuf.Length + payloadLen;
Data.segment.AddMaster(mstr, payloadLenBuf.Length + payloadLen);
}
else
{
var newNode = ParseTree(mstr);
if (IssueModel.Data.HasFatal)
{
if (newNode != null)
{
Data.segment.AddNode(newNode);
}
return;
}
Data.segment.AddNode(newNode);
}
goto NEXT_SEG;
}
}
string msg = $"Parse fail at 0x{Data.ValidSize:X} on [{bb[0]:X2}][{bb[1]:X2}][{bb[2]:X2}][{bb[3]:X2}].";
IssueModel.Add(msg, Severity.Fatal);
return;
NEXT_SEG :;
}
Data.fbs.Position = Data.ValidSize;
var got2 = Data.fbs.Read(bb, 0, 4);
if (got2 == 4 && attachSig.SigIsStartOf(bb))
{
// By spec, everything should be within a single Segment.
Data.HasMisplacedAttachment = true;
IssueModel.Add($"Misplaced attachment at {Data.ValidSize:X}", Severity.Warning);
}
Data.fbs.Position = Data.ValidSize;
CalcMark(true);
return;
}
