+}
+bool SummationImplementation::AddFD(FileFd &Fd, unsigned long long Size) {
+ unsigned char Buf[64 * 64];
+ bool const ToEOF = (Size == 0);
+ while (Size != 0 || ToEOF)
+ {
+ unsigned long long n = sizeof(Buf);
+ if (!ToEOF) n = std::min(Size, n);
+ unsigned long long a = 0;
+ if (Fd.Read(Buf, n, &a) == false) // error
+ return false;
+ if (ToEOF == false)
+ {
+ if (a != n) // short read
+ return false;
+ }
+ else if (a == 0) // EOF
+ break;
+ Size -= a;
+ Add(Buf, a);
+ }
+ return true;