private void LoadNotes()
{
if (_notes != null)
{
return;
}
LoadProgramHeaders();
ElfProgramHeader noteHeader = _programHeaders.SingleOrDefault(ph => ph.Header.Type == ELFProgramHeaderType.Note);
if (noteHeader == null)
{
_notes = new ElfNote[0];
return;
}
List <ElfNote> notes = new List <ElfNote>();
Reader reader = new Reader(noteHeader.AddressSpace);
long position = 0;
while (position < reader.DataSource.Length)
{
ElfNote note = new ElfNote(reader, position);
notes.Add(note);
position += note.TotalSize;
}
_notes = notes.ToArray();
}
private int GetFirstSegmentContaining(long address)
{
int lower = 0;
int upper = _segments.Length - 1;
while (lower <= upper)
{
int mid = (lower + upper) >> 1;
ElfProgramHeader segment = _segments[mid];
long virtualAddress = segment.VirtualAddress;
long virtualSize = segment.VirtualSize;
if (virtualAddress <= address && address < virtualAddress + virtualSize)
{
while (mid > 0 && address < _segments[mid - 1].VirtualAddress + _segments[mid - 1].VirtualSize)
{
mid--;
}
return(mid);
}
if (address < virtualAddress)
{
upper = mid - 1;
}
else
{
lower = mid + 1;
}
}
return(-1);
}
public ElfVirtualAddressSpace(ImmutableArray <ElfProgramHeader> segments, IAddressSpace addressSpace)
{
// FileSize == 0 means the segment isn't backed by any data
_segments = segments.Where(segment => segment.FileSize > 0).OrderBy(segment => segment.VirtualAddress).ThenBy(segment => segment.VirtualSize).ToArray();
ElfProgramHeader lastSegment = _segments[_segments.Length - 1];
Length = lastSegment.VirtualAddress + lastSegment.FileSize;
_addressSpace = addressSpace;
}
public int Read(long address, Span <byte> buffer)
{
if (address == 0 || buffer.Length == 0)
{
return(0);
}
int i = GetFirstSegmentContaining(address);
if (i < 0)
{
return(0);
}
int bytesRead = 0;
for (; i < _segments.Length; i++)
{
ElfProgramHeader segment = _segments[i];
long virtualAddress = segment.VirtualAddress;
long virtualSize = segment.VirtualSize;
if (virtualAddress > address)
{
break;
}
if (address >= virtualAddress + virtualSize)
{
continue;
}
long offset = address - virtualAddress;
int toRead = (int)Math.Min(buffer.Length - bytesRead, virtualSize - offset);
Span <byte> slice = buffer.Slice(bytesRead, toRead);
int read = segment.AddressSpace.Read(offset, slice);
if (read < toRead)
{
break;
}
bytesRead += read;
if (bytesRead == buffer.Length)
{
break;
}
address += read;
}
return(bytesRead);
}
private void LoadProgramHeaders()
{
if (_programHeaders != null)
{
return;
}
_programHeaders = new ElfProgramHeader[Header.ProgramHeaderCount];
for (int i = 0; i < _programHeaders.Length; i++)
{
_programHeaders[i] = new ElfProgramHeader(_reader, _position + (long)Header.ProgramHeaderOffset + i * Header.ProgramHeaderEntrySize, _position, _virtual);
}
}
public int Read(long position, Span <byte> buffer)
{
int bytesRead = 0;
while (bytesRead != buffer.Length)
{
int i = 0;
for (; i < _segments.Length; i++)
{
ElfProgramHeader segment = _segments[i];
long virtualAddress = segment.VirtualAddress;
long virtualSize = segment.VirtualSize;
long upperAddress = virtualAddress + virtualSize;
if (virtualAddress <= position && position < upperAddress)
{
int bytesToReadRange = (int)Math.Min(buffer.Length - bytesRead, upperAddress - position);
long segmentOffset = position - virtualAddress;
Span <byte> slice = buffer.Slice(bytesRead, bytesToReadRange);
int bytesReadRange = segment.AddressSpace.Read(segmentOffset, slice);
if (bytesReadRange == 0)
{
goto done;
}
position += bytesReadRange;
bytesRead += bytesReadRange;
if (bytesReadRange < bytesToReadRange)
{
goto done;
}
break;
}
}
if (i == _segments.Length)
{
break;
}
}
done:
buffer.Slice(bytesRead).Clear();
return(bytesRead);
}
