Expands the kernel-and-TTY core with the primitives the higher layers have
been missing, plus an in-kernel harness that proves they work.
Data structures (lib/):
- rbtree.c: Linux-compatible red-black tree with parent pointers, full
insert/erase rebalancing, in-order iteration and an invariant validator.
- kfifo.c: power-of-two byte ring with free-running indices, so the wrap
path costs one mask instead of a branch per byte.
- hashtable.c: separately-chained table with FNV-1a hashing, string or
u64 keys, and rehash-on-growth at a 3/4 load factor.
Kernel subsystems:
- kernel/wait.c: wait queues and one-shot completion barriers, backed by a
static sleeper pool so a blocking path never re-enters the allocator.
- kernel/futex.c: 32-bucket futex hash with value re-check, requeue, and an
fmutex_t sleeping mutex built on the uncontended-fastpath protocol.
- kernel/rcu.c: tiny RCU with reader nesting, deferred callbacks, kfree_rcu
and rcu_assign_pointer/rcu_dereference publish barriers.
- mm/page_cache.c: write-back block page cache, 4 KB pages indexed by
(device, page), CLOCK second-chance eviction and dirty write-back.
- kernel/ktest.c: KUnit-style harness with 6 built-in suites, 21 cases and
735 assertions covering every subsystem above (all passing under QEMU).
LazyBox userland:
- coreutils.c: sort, uniq, cut, tr, rev, tac, nl, seq, diff, xxd, du,
factor, sum and truncate, reading through the VFS and handling the
zero-length synthetic nodes that procfs and sysfs expose.
- ktest, rcuinfo, futexinfo, waitinfo and pagecache diagnostics applets.
Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01L5yKJT4Wo2cV3rfPrwY5MP
- Create separate feature branch 'feat/gui-desktop'
- Implement double-buffered 2D graphics engine with alpha blending, gradients, rounded rects, and font rasterization in gui/gui_gfx.c and include/gui/gui_gfx.h
- Implement alpha-blended mouse pointer overlay in gui/gui_cursor.c and include/gui/gui_cursor.h
- Implement SUB-WM Window Manager with draggable titlebars, close/minimize buttons, drop shadows, and event routing in gui/gui_wm.c and include/gui/gui_wm.h
- Implement Cyberpunk/Nord desktop environment with wallpaper, taskbar, start menu popup, and system tray in gui/gui_desktop.c and include/gui/gui_desktop.h
- Implement built-in GUI apps: System Performance Monitor, GUI Terminal Emulator, File Explorer, Calculator, Paint Studio, and About dialog in gui/gui_apps.c and include/gui/gui_apps.h
- Add 'startx', 'gui', and 'desktop' applets in LazyBox suite
- Verified multi-architecture compilation across x86_64, AArch64, and ARMv8i
- Implement Intel 82574L / 82567LM / I217 / I219 PCIe Gigabit NIC driver with DMA ring buffers and auto-negotiation in drivers/net/e1000e.c and include/drivers/e1000e.h
- Implement VirtIO-GPU 2D hardware graphics display adapter driver with dirty rect flushing in drivers/virtio/virtio_gpu.c and include/drivers/virtio_gpu.h
- Implement Dynamic CPU Frequency Scaling and ACPI CPPC Power Governor with performance, powersave, ondemand, conservative, and schedutil policies in drivers/power/cpufreq.c and include/drivers/cpufreq.h
- Implement VirtIO-Input para-virtualized tablet/mouse event driver in drivers/virtio/virtio_input.c and include/drivers/virtio_input.h
- Expand stage2 kernel bootloader loading boundary to 768 KB (1536 sectors)
- Add LazyBox applets: 'cpufreq', 'gpuinfo', 'e1000e'
- Verified across x86_64, AArch64, and ARMv8i targets
- Add dedicated Linux-compatible Tree visualizer with UTF-8/ASCII branch tracking, -L depth filtering, human sizes, and permissions in userland/lazybox/tree.c
- Implement Hardware Invariant Timestamp Counter (TSC) calibration and microsecond delay timer in kernel/tsc.c and include/kernel/tsc.h
- Add Virtual Terminal color palette, live resource utilization bars, and logo banner in kernel/vt_art.c and include/kernel/vt_art.h
- Add LazyBox applets: 'tree', 'tscinfo', and 'vtart'
- Update README.md documentation and command matrix
- Implement modern freestanding C++17 containers (Vector<T>, UniquePtr<T>, String) in kernel/cpp/cpp_containers.hpp
- Implement object-oriented Device driver model (Device, BlockDevice, CharDevice, VirtualRamDiskDevice, VirtualNullDevice, VirtualZeroDevice, DeviceManager) in kernel/cpp/cpp_device.hpp and kernel/cpp/cpp_device.cpp
- Add C++ kernel performance microbenchmark suite in kernel/cpp/cpp_bench.cpp
- Export C-FFI bridges and add cross-architecture fallbacks in kernel/cpp/cpp_fallback.c and include/kernel/cpp_kernel.h
- Add LazyBox applets: 'cppdevs' and 'cppbench'
- Update README.md documentation and command matrix
- Implement flicker-free atomic double-buffered frame rendering and sub-tick input polling in userland/lazybox/snake.c
- Add multi-input support (PS/2 keyboard scancodes and serial ANSI arrow escape sequences)
- Add sound effects (food beep, game over chime) and live speed scaling (+/- keys, P to pause)
- Add POSIX /dev/shm shared memory subsystem in ipc/shm_posix.c and include/ipc/shm_posix.h
- Add DNS resolver cache with TTL tracking in net/ipv4/dns_cache.c and include/net/dns_cache.h
- Add audio tone and jingle synthesizer in sound/beep.c and include/sound/beep.h
- Add %o octal formatting support in lib/vsprintf.c
- Add LazyBox applets: 'shm', 'dnscache', and 'beep'
- Add freestanding C++17 runtime with operator new/delete, pure virtual handlers, and global constructor execution in kernel/cpp/cxx_runtime.cpp
- Implement C++ Object-Oriented telemetry and hardware services with polymorphism in kernel/cpp/cpp_module.cpp and include/kernel/cpp_kernel.h
- Add interactive ANSI Snake Game in userland/lazybox/snake.c with real-time keyboard control and automated simulation mode
- Initialize C++ subsystem during kernel boot step [8/14] in kernel/main.c
- Add LazyBox applets: 'snake', 'cppinfo', and 'cpptest'
- Support 'armv81' and 'armv81_defconfig' aliases in Makefile and Kconfig menuconfig.py
- Fix uint64_t to pointer cast on 32-bit ARM in LazyBox shell.c
- Add native .sb kernel modules in sub/ (signature.sb, power_governor.sb, benchmark.sb, easter_egg.sb)
- Implement in-kernel SUB Language VM and AST interpreter in kernel/sub/sub_vm.c
- Implement C-interop runtime in kernel/sub/sub_runtime.c and include/kernel/sub_lang.h
- Initialize SUB Language Engine in boot sequence step [8/14] in kernel/main.c
- Implement strtol in lib/string.c
- Add LazyBox applets: 'subinfo', 'subi', 'subpower', 'subbench', and 'subquote'
- Add 'clear' and 'cls' builtin handlers in LazyBox shell
- Output ANSI \033[2J\033[H sequence on tty_clear() to clear serial/UART terminals
- Support both ASCII 0x7F (DEL) and 0x08 (BS) for Backspace in shell and nano editor
- Connect 16550 serial input to keyboard_get_key() on x86_64 for headless terminals
- Add ANSI escape sequence decoding for arrow keys (Up/Down/Left/Right/Home/End/Del)
- Update Makefile 'make run' and 'make qemu' with -display none for smooth terminal execution
- Add 'make run-gui' target for optional graphical SDL/GTK window
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