private bool Read(FrameFile ff)
{
if (_fc1 < 0)
{
if (!ff.Read(_buf1))
{
return(false);
}
_fc1 = FrameAccessor.FrameCount(_buf1);
return(true);
}
if (_fc2 < 0)
{
if (!ff.Read(_buf2))
{
return(false);
}
_fc2 = FrameAccessor.FrameCount(_buf2);
return(true);
}
throw new Exception("No free frame buffers");
}
public override IEnumerable <byte[]> Iterator()
{
var state = State.Idle;
var packet = new byte[65516 + 12]; // add some margin 65536 bytes of data plus 6 of header + 6 of timestamp
var frameCounter = 0;
var packetPtr = 0; // copy pointer into the packet array
var framePtr = 0; // copy pointer into the frame array
foreach (var frame in FrameIterator())
{
var virtualChannel = FrameAccessor.VirtualChannel(frame);
//Console.WriteLine("VirtualChannel={0}", virtualChannel);
if (virtualChannel != VirtualChannel)
{
continue;
}
var frameCount = FrameAccessor.FrameCount(frame);
//Console.WriteLine("FrameCount={0}", frameCounter);
var firstPacketPtr = FrameAccessor.FirstHeaderPointer(frame);
switch (state)
{
case State.Idle:
if (firstPacketPtr == FrameAccessor.FirstHeaderPointerOverflow)
{
break; // No packet starts here
}
framePtr = firstPacketPtr + FrameAccessor.MPDUStart;
state = State.Running;
frameCounter = frameCount;
packetPtr = 0;
goto case State.Iterate;
case State.Running:
frameCounter++;
if (frameCounter != frameCount && !(frameCount == 0 && frameCounter == 16777216))
{
var delta = frameCount - frameCounter;
if (delta < 0)
{
delta += 16777216;
}
if (LogLevel > 0)
{
Console.Error.WriteLine(@"Frame sequence error: expected {0}, saw {1}, {2} frames skipped", frameCounter, frameCount, delta);
}
state = State.Idle;
continue;
}
framePtr = FrameAccessor.MPDUStart;
if (firstPacketPtr == 0)
{
if (packetPtr > 0)
{
CheckPacketLength(packet, packetPtr); // Get rid of this after debugging
yield return(packet);
packetPtr = 0;
}
goto case State.Iterate;
}
if (firstPacketPtr == FrameAccessor.FirstHeaderPointerOverflow)
{
AppendToPacket(frame, FrameAccessor.MPDUPacketZoneLength, packet, ref framePtr,
ref packetPtr);
break;
}
if (firstPacketPtr == 2047)
{
// Idle Frame
break;
}
if (firstPacketPtr > 0)
{
AppendToPacket(frame, firstPacketPtr, packet, ref framePtr, ref packetPtr);
{
CheckPacketLength(packet, packetPtr); // Get rid of this after debugging
yield return(packet);
packetPtr = 0;
}
goto case State.Iterate;
}
break;
case State.Iterate:
{
var flag = true;
while (flag)
{
var gap = FrameAccessor.MPDUEnd - framePtr;
if (gap < PacketAccessor.PacketFixedHeaderLength)
{
// This packet must extend past
for (var i = 0; i < gap; i++)
{
packet[packetPtr++] = frame[framePtr++];
}
flag = false;
continue;
}
for (var i = 0; i < PacketAccessor.PacketFixedHeaderLength; i++)
{
packet[packetPtr++] = frame[framePtr++];
}
var len = PacketAccessor.Length(packet) + 1; // real length is always the field + 1
gap = FrameAccessor.MPDUEnd - framePtr;
if (gap <= 0)
{
flag = false;
continue;
}
if (gap >= len)
{
// it'll fit
AppendToPacket(frame, len, packet, ref framePtr, ref packetPtr);
{
CheckPacketLength(packet, packetPtr); // Get rid of this after debugging
yield return(packet);
packetPtr = 0;
}
flag = (gap > len); // Maybe it fits just barely
continue;
}
// It won't fit
AppendToPacket(frame, gap, packet, ref framePtr, ref packetPtr);
flag = false;
}
}
break;
}
}
// Should there be a yield break here?
}
public static IEnumerable <byte[]> Iterator(IEnumerable <byte[]> frames)
{
var state = new FrameFileSequence.State[64];
for (var i = 0; i < 63; i++)
{
state[i] = FrameFileSequence.State.Idle;
}
var packet = new byte[64][];
const int bufferSize = 65516 + 12; // add some margin 65536 bytes of data plus 6 of header + 6 of timestamp
var frameCounter = new int[64]; // initial values of 0
var packetPtr = new int[64]; // copy pointer into the packet array
var framePtr = new int[64]; // copy pointer into the frame array
foreach (var frame in frames)
{
var vc = FrameAccessor.VirtualChannel(frame);
if (packet[vc] == null)
{
packet[vc] = new byte[bufferSize];
}
//Console.WriteLine("VirtualChannel={0}", vc);
//if (vc != 1) continue;
var frameCount = FrameAccessor.FrameCount(frame);
//Console.WriteLine("FrameCount={0} State={1}", frameCounter[vc], state[vc]);
var firstPacketPtr = FrameAccessor.FirstHeaderPointer(frame);
switch (state[vc])
{
case FrameFileSequence.State.Idle:
if (firstPacketPtr == FrameAccessor.FirstHeaderPointerOverflow)
{
break; // No packet starts here
}
framePtr[vc] = firstPacketPtr + FrameAccessor.MPDUStart;
state[vc] = FrameFileSequence.State.Running;
frameCounter[vc] = frameCount;
packetPtr[vc] = 0;
goto case FrameFileSequence.State.Iterate;
case FrameFileSequence.State.Running:
frameCounter[vc]++;
if (frameCounter[vc] != frameCount && !(frameCount == 0 && frameCounter[vc] == 16777216))
{
var delta = frameCount - frameCounter[vc];
if (delta < 0)
{
delta += 16777216;
}
//if (LogLevel > 0)
// Console.WriteLine(@"Frame sequence error: expected {0}, saw {1}, {2} frames skipped", frameCounter[vc], frameCount, delta);
state[vc] = FrameFileSequence.State.Idle;
continue;
}
framePtr[vc] = FrameAccessor.MPDUStart;
if (firstPacketPtr == 0)
{
if (packetPtr[vc] > 0)
{
CheckPacketLength(packet[vc], packetPtr[vc]); // Get rid of this after debugging
yield return(packet[vc]);
packetPtr[vc] = 0;
}
goto case FrameFileSequence.State.Iterate;
}
if (firstPacketPtr == FrameAccessor.FirstHeaderPointerOverflow)
{
AppendToPacket(frame, FrameAccessor.MPDUPacketZoneLength, packet[vc], ref framePtr[vc],
ref packetPtr[vc]);
break;
}
if (firstPacketPtr == 2047)
{
// Idle Frame
break;
}
if (firstPacketPtr > 0)
{
AppendToPacket(frame, firstPacketPtr, packet[vc], ref framePtr[vc], ref packetPtr[vc]);
{
CheckPacketLength(packet[vc], packetPtr[vc]); // Get rid of this after debugging
yield return(packet[vc]);
packetPtr[vc] = 0;
}
goto case FrameFileSequence.State.Iterate;
}
break;
case FrameFileSequence.State.Iterate:
{
var flag = true;
var p = packet[vc];
while (flag)
{
var gap = FrameAccessor.MPDUEnd - framePtr[vc];
if (gap < PacketAccessor.PacketFixedHeaderLength)
{
// This packet must extend past
for (var i = 0; i < gap; i++)
{
p[packetPtr[vc]++] = frame[framePtr[vc]++];
}
flag = false;
continue;
}
for (var i = 0; i < PacketAccessor.PacketFixedHeaderLength; i++)
{
p[packetPtr[vc]++] = frame[framePtr[vc]++];
}
var len = PacketAccessor.Length(p) + 1; // real length is always the field + 1
gap = FrameAccessor.MPDUEnd - framePtr[vc];
if (gap <= 0)
{
flag = false;
continue;
}
if (gap >= len)
{
// it'll fit
AppendToPacket(frame, len, p, ref framePtr[vc], ref packetPtr[vc]);
{
CheckPacketLength(p, packetPtr[vc]); // Get rid of this after debugging
yield return(p);
packetPtr[vc] = 0;
}
flag = (gap > len); // Maybe it fits just barely
continue;
}
// It won't fit
AppendToPacket(frame, gap, p, ref framePtr[vc], ref packetPtr[vc]);
flag = false;
}
}
break;
}
}
// Should there be a yield break here?
}