private bool ReadTraceHeader()
{
// Read Trace Header
CtfStruct traceHeader = _metadata.Trace.Header;
int traceHeaderSize = traceHeader.GetSize();
if (traceHeaderSize == CtfEvent.SizeIndeterminate)
{
throw new FormatException("Unexpected metadata format.");
}
int magicOffset = traceHeader.GetFieldOffset("magic");
if (magicOffset < 0)
{
throw new FormatException("Unexpected metadata format: No magic field.");
}
int streamIdOffset = traceHeader.GetFieldOffset("stream_id");
if (streamIdOffset < 0)
{
throw new FormatException("Unexpected metadata format: No stream_id field.");
}
// Convert to bytes instead of bits
magicOffset /= 8;
streamIdOffset /= 8;
traceHeaderSize /= 8;
if (_stream.Read(_buffer, 0, traceHeaderSize) != traceHeaderSize)
{
return(false);
}
#if DEBUG
_fileOffset += traceHeaderSize;
#endif
uint magic = BitConverter.ToUInt32(_buffer, magicOffset);
if (magic != 0xc1fc1fc1)
{
throw new FormatException("Unknown magic number in trace header.");
}
uint streamId = BitConverter.ToUInt32(_buffer, streamIdOffset);
_ctfStream = _metadata.Streams[streamId];
return(true);
}
private bool ReadPacketContext()
{
// Read Packet Context
CtfStruct packetContext = _ctfStream.PacketContext;
int packetContextSize = packetContext.GetSize();
if (packetContextSize == CtfEvent.SizeIndeterminate)
{
throw new FormatException("Unexpected metadata format.");
}
int contentSizeOffset = packetContext.GetFieldOffset("content_size");
if (contentSizeOffset < 0)
{
throw new FormatException("Unexpected metadata format: No context_size field.");
}
int packetSizeOffset = packetContext.GetFieldOffset("packet_size");
if (packetSizeOffset < 0)
{
throw new FormatException("Unexpected metadata format: No packet_size field.");
}
// Convert to bytes instead of bits
packetContextSize /= 8;
contentSizeOffset /= 8;
packetSizeOffset /= 8;
if (_stream.Read(_buffer, 0, packetContextSize) != packetContextSize)
{
return(false);
}
#if DEBUG
_fileOffset += packetContextSize;
#endif
int headerSize = (_metadata.Trace.Header.GetSize() / 8) + packetContextSize;
_contentSize = (long)BitConverter.ToUInt64(_buffer, contentSizeOffset) / 8 - headerSize;
_packetSize = (long)BitConverter.ToUInt64(_buffer, packetSizeOffset) / 8 - headerSize;
return(true);
}