CS144Lab/libsponge/wrapping_integers.cc
2021-09-28 17:04:25 -07:00

35 lines
1.3 KiB
C++

#include "wrapping_integers.hh"
// Dummy implementation of a 32-bit wrapping integer
// For Lab 2, please replace with a real implementation that passes the
// automated checks run by `make check_lab2`.
template <typename... Targs>
void DUMMY_CODE(Targs &&... /* unused */) {}
using namespace std;
//! Transform an "absolute" 64-bit sequence number (zero-indexed) into a WrappingInt32
//! \param n The input absolute 64-bit sequence number
//! \param isn The initial sequence number
WrappingInt32 wrap(uint64_t n, WrappingInt32 isn) {
DUMMY_CODE(n, isn);
return WrappingInt32{0};
}
//! Transform a WrappingInt32 into an "absolute" 64-bit sequence number (zero-indexed)
//! \param n The relative sequence number
//! \param isn The initial sequence number
//! \param checkpoint A recent absolute 64-bit sequence number
//! \returns the 64-bit sequence number that wraps to `n` and is closest to `checkpoint`
//!
//! \note Each of the two streams of the TCP connection has its own ISN. One stream
//! runs from the local TCPSender to the remote TCPReceiver and has one ISN,
//! and the other stream runs from the remote TCPSender to the local TCPReceiver and
//! has a different ISN.
uint64_t unwrap(WrappingInt32 n, WrappingInt32 isn, uint64_t checkpoint) {
DUMMY_CODE(n, isn, checkpoint);
return {};
}