BUPT(Beijing University of Posts and Telecommunications) school projects index

• Built using C++17/CMake
  • Use Catch2 for testing
• Use Flex & Bison for Scanner and SLR Parser
• Implemented a GUI wrapper using Electron
  • Use Emscripten for a convenient WebAssembly library

• 2 versions:
  • A hand-written DFA in pure C
  • flex version using regex matching
• Implements yylex() API that resembles flex

• implemented LL(1)/SLR(1) parser for a given grammar in C
• use flex for scanner
• hard-coded LR DFA table

The labs includes:

• use syscalls to write user-space utils like sleep, xargs, find
• implements new syscalls including mmap(), symlink()
• implements enhancements including copy on write, lazy allocation

• designed 3 versions of protocols: stop and wait, go back n, selective repeat
• optimized version selective repeat reached theoretical value of efficiency
  • optimized by carefully select window size and max retries
  • designed a special NAK strategy to reduce latency

• supports A, AAAA local query and remote DNS server relay, which resembles dnsmasq (but without dhcp server functionality)
• UDP query only. Implemented addr decompression but didn’t implement compression
• Multithreading using pthread library

• built with C++14+CMake
  • taking advantages of OOP & templates & RAII
  • parallel with std::thread
• interactive cli interface
• Doc generation with Doxygen
• use SQLite3 with SQLite ORM
• use TCP sockets for connection(using http is not allowed)