public MsfDirectory(PdbReader reader, int pageSize, int directorySize, int[] directoryRoot)
{
var numPages = reader.PagesFromSize(directorySize);
var pages = new int[numPages];
Span <byte> buf = MemoryMarshal.Cast <int, byte>(pages);
var offset = 0;
var pagesPerPage = pageSize / 4;
var pagesToGo = numPages;
foreach (var t in directoryRoot)
{
var pagesInThisPage = pagesToGo <= pagesPerPage ? pagesToGo : pagesPerPage;
reader.Seek(t, 0);
reader.Stream.Read(buf.Slice(offset, pagesInThisPage * 4));
pagesToGo -= pagesInThisPage;
}
using var buffer = new SafeArrayPool <byte>(directorySize);
var stream = new DataStream(directorySize, pages);
stream.Read(reader, buffer.Array);
offset = 0;
var count = InterpretInt32(buffer.Array, ref offset);
using var sizesPool = new SafeArrayPool <int>(count);
int[] sizes = sizesPool.Array;
for (var i = 0; i < count; ++i)
{
sizes[i] = InterpretInt32(buffer.Array, ref offset);
}
this.streams = new DataStream[count];
for (var i = 0; i < count; ++i)
{
if (sizes[i] <= 0)
{
this.streams[i] = new DataStream();
}
else
{
var dsPagesCount = reader.PagesFromSize(sizes[i]);
if (dsPagesCount > 0)
{
var dsPages = new int[dsPagesCount];
for (var j = 0; j < dsPagesCount; ++j)
{
dsPages[j] = InterpretInt32(buffer.Array, ref offset);
}
this.streams[i] = new DataStream(sizes[i], dsPages);
}
else
{
this.streams[i] = new DataStream(sizes[i], Array.Empty <int>());
}
}
}
}