public FixupRecord(RecordReader reader, RecordContext context)
: base(reader, context)
{
List <FixupThreadDefinition> threads = new List <FixupThreadDefinition>();
List <FixupDefinition> fixups = new List <FixupDefinition>();
while (!reader.IsEOF)
{
byte b = reader.PeekByte();
if ((b & 0x80) == 0)
{
FixupThreadDefinition thread = ParseThreadSubrecord(reader);
threads.Add(thread);
if (thread.Kind == FixupThreadKind.Target)
{
context.TargetThreads[thread.ThreadNumber] = thread;
}
else
{
context.FrameThreads[thread.ThreadNumber] = thread;
}
}
else
{
FixupDefinition fixup = ParseFixupSubrecord(reader, context);
fixups.Add(fixup);
if (context.LastRecord is LEDATARecord)
{
var r = (LEDATARecord)context.LastRecord;
fixup.DataOffset += (ushort)r.DataOffset;
r.Segment.Fixups.Add(fixup);
}
else if (context.LastRecord is LIDATARecord)
{
}
else if (context.LastRecord is COMDATRecord)
{
}
else
{
throw new InvalidDataException("FIXUPP record must follow LEDATA, LIDATA, or COMDAT record.");
}
}
}
this.Threads = threads.ToArray();
this.Fixups = fixups.ToArray();
}
private FixupThreadDefinition ParseThreadSubrecord(RecordReader reader)
{
FixupThreadDefinition thread = new FixupThreadDefinition();
byte b = reader.ReadByte();
thread.Kind = ((b & 0x40) == 0) ? FixupThreadKind.Target : FixupThreadKind.Frame;
thread.Method = (byte)((b >> 2) & 3);
thread.ThreadNumber = (byte)(b & 3);
if (thread.Method <= 2) // TBD: should be 3 for intel
{
thread.IndexOrFrame = reader.ReadIndex();
}
thread.IsDefined = true;
return(thread);
}
private FixupThreadDefinition ParseThreadSubrecord(RecordReader reader)
{
FixupThreadDefinition thread = new FixupThreadDefinition();
byte b = reader.ReadByte();
thread.Kind = ((b & 0x40) == 0) ? FixupThreadKind.Target : FixupThreadKind.Frame;
thread.Method = (byte)((b >> 2) & 3);
thread.ThreadNumber = (byte)(b & 3);
if (thread.Method <= 2) // TBD: should be 3 for intel
thread.IndexOrFrame = reader.ReadIndex();
thread.IsDefined = true;
return thread;
}
private FixupDefinition ParseFixupSubrecord(RecordReader reader, RecordContext context)
{
FixupDefinition fixup = new FixupDefinition();
byte b1 = reader.ReadByte();
byte b2 = reader.ReadByte();
UInt16 w = (UInt16)((b1 << 8) | b2); // big endian
fixup.Mode = (w & 0x4000) != 0 ? FixupMode.SegmentRelative : FixupMode.SelfRelative;
fixup.Location = (FixupLocation)((w >> 10) & 0x0F);
fixup.DataOffset = (UInt16)(w & 0x03FF);
byte b = reader.ReadByte();
bool useFrameThread = (b & 0x80) != 0;
if (useFrameThread)
{
int frameNumber = (b >> 4) & 0x3;
FixupThreadDefinition thread = context.FrameThreads[frameNumber];
if (!thread.IsDefined)
{
throw new InvalidDataException("Frame thread " + frameNumber + " is not defined.");
}
FixupFrame spec = new FixupFrame();
spec.Method = (FixupFrameMethod)thread.Method;
spec.IndexOrFrame = thread.IndexOrFrame;
fixup.Frame = spec;
}
else
{
FixupFrame spec = new FixupFrame();
spec.Method = (FixupFrameMethod)((b >> 4) & 7);
if ((int)spec.Method <= 3)
{
spec.IndexOrFrame = reader.ReadIndex();
}
fixup.Frame = spec;
}
bool useTargetThread = (b & 0x08) != 0;
if (useTargetThread)
{
bool hasTargetDisplacement = (b & 0x04) != 0;
int targetNumber = b & 3;
FixupThreadDefinition thread = context.TargetThreads[targetNumber];
if (!thread.IsDefined)
{
throw new InvalidDataException("Target thread " + targetNumber + " is not defined.");
}
FixupTargetMethod method = (FixupTargetMethod)((int)thread.Method & 3);
if (hasTargetDisplacement)
{
method |= (FixupTargetMethod)4;
}
FixupTarget spec = new FixupTarget();
spec.Referent = ResolveFixupReferent(context, method, thread.IndexOrFrame);
if ((int)method <= 3)
{
spec.Displacement = reader.ReadUInt16Or32();
}
fixup.Target = spec;
}
else
{
FixupTargetMethod method = (FixupTargetMethod)(b & 7);
UInt16 indexOrFrame = reader.ReadIndex();
FixupTarget spec = new FixupTarget();
spec.Referent = ResolveFixupReferent(context, method, indexOrFrame);
if ((int)method <= 3)
{
spec.Displacement = reader.ReadUInt16Or32();
}
fixup.Target = spec;
}
return(fixup);
}
