# ViperOS

[English](#english) | [中文](#中文)

A bare-metal 64-bit operating system written in the [Viper](https://git.gvsds.com/GVSDS/TransPyC) language. Boots via UEFI, ships a self-implemented FAT32 driver, runs ELF-format user applications, and includes a complete user-space SDK.

用 [Viper](https://git.gvsds.com/GVSDS/TransPyC) 语言编写的裸机 64 位操作系统。UEFI 启动、自研 FAT32 驱动、运行 ELF 格式用户程序，配套完整的用户态 SDK。

---

<a id="中文"></a>

## 中文

### 这是什么

`ViperOS` 是 Viper 语言的旗舰演示项目：**一个完整可启动的操作系统**。和"Linux 发行版"或"教学用 mini-OS"不同，ViperOS 用 Viper 写一切——内核、设备驱动、用户程序、库、SDK 都用同一种语言（Viper 的 Python 语法 + LLVM 后端）。

主要组成：
- **VKernel** —— 64 位微内核（x86_64-none-elf 目标）
- **UEFI 引导器** —— `boot/boot.c`（GNU-EFI 编译为 `disk/EFI/BOOT/bootx64.efi`）
- **FAT32 驱动** —— 自研实现，支持挂载、目录、文件操作
- **4 个用户应用** —— HelloWorld / Terminal / Gargantua / Scene3D
- **2 个动态库** —— SerialLogger / VPUI64
- **ViperPOS SDK** —— 用户态开发库（系统调用、窗口、文件系统、进程）

### 目录结构

```
ViperOS/
├── .gitignore              # 忽略所有 output/、temp/、构建产物
├── build.py                # 顶层构建入口：构建→打包→启动 QEMU
├── linker.ld               # 顶层链接脚本
├── boot/                   # UEFI 引导器
│   ├── Makefile
│   └── boot.c
├── VKernel/                # 内核
│   ├── project.json        # 内核构建配置
│   ├── linker.ld
│   └── Kernel/
│       ├── main.py         # 内核入口
│       ├── bootinfo.py
│       ├── drivers/        # 驱动
│       │   ├── core/cpu/   # APIC、CPU、FPU
│       │   ├── devfs/      # 设备文件系统
│       │   ├── fs/fat32/   # FAT32 驱动（自研）
│       │   ├── input/      # 键盘、鼠标
│       │   ├── serial/     # 8250 UART
│       │   ├── storage/    # IDE
│       │   ├── usb/        # USB HID / UHCI
│       │   └── video/      # VESA Framebuffer + UI
│       ├── execrunner/     # ELF 加载器
│       ├── intr/           # 中断子系统（GDT/IDT/ISR/Syscall）
│       ├── mm/             # 内存管理
│       ├── paging/         # 分页
│       ├── sched/          # 协程、进程、调度
│       ├── services/       # 内核服务
│       └── platform/       # 平台相关（PIC/PIT/RTC/Timer）
├── Apps/                   # 用户应用（每个子目录一个独立 ELF）
│   ├── HelloWorld/
│   ├── Terminal/
│   ├── Gargantua/
│   └── Scene3D/
├── Libs/                   # 动态库（每个子目录一个 .so）
│   ├── SerialLogger/
│   └── VPUI64/
├── vpsdk/                  # ViperPOS SDK（应用开发用）
│   ├── __init__.py
│   ├── stdlib.py
│   ├── syscall.py
│   ├── window.py
│   ├── vpui.py
│   ├── fs.py
│   ├── process.py
│   ├── dynlib.py
│   └── wiki/               # SDK 自带 wiki
├── Scripts/
│   ├── check_disk.py
│   ├── disk.ps1            # ImDisk 打包 FAT32 镜像
│   └── disk.sh             # Linux 等价脚本
└── disk/                   # 被打包进 disk.img 的文件
    ├── EFI/BOOT/bootx64.efi
    ├── app/helloworld.asm
    ├── apps/               # .elf 拷贝目标（构建时填充）
    ├── libs/               # .so 拷贝目标（构建时填充）
    └── sys/kernel/x86_64/kernel.bin
```

### 前提条件

| 工具 | 说明 |
|------|------|
| `python` ≥ 3.10 | 运行 TransPyC 编译器 |
| `llc` | LLVM 静态编译器 |
| `ld.lld` | LLD 链接器（裸机版本） |
| `qemu-system-x86_64` | QEMU 模拟器 |
| `imdisk` | Windows 下创建/挂载磁盘镜像的驱动；Linux 平台用 `disk.sh` 替代 |
| `gnu-efi` 工具链 | 编译 UEFI 引导器（`boot/boot.c`） |
| [TransPyC](https://git.gvsds.com/GVSDS/TransPyC) | 编译器，**必须克隆在与 ViperOS 同级的目录** |

目录布局要求：

```
D:\Users\TermiNexus\Desktop\TransPyC\
├── TransPyC\        # 编译器仓库
├── ViperOS\         # 本仓库
└── ViperTemplateProject\
```

### 快速开始

```powershell
# 1. 在 ViperOS 目录下直接运行
cd D:\Users\TermiNexus\Desktop\TransPyC\ViperOS

# 2. 完整构建并启动 QEMU
python build.py

# 3. 串口日志写入 serial.log
```

`build.py` 会自动完成：
1. 调用 `Projectrans.py` 编译 VKernel → `VKernel/output/kernel.bin`
2. 编译 2 个动态库（SerialLogger、VPUI64）
3. 编译 4 个应用（HelloWorld、Terminal、Gargantua、Scene3D）
4. 拷贝所有产物到 `disk/apps/`、`disk/libs/`、`disk/sys/kernel/x86_64/`
5. 调用 `Scripts/disk.ps1` 创建 64MB FAT32 镜像 `disk.img`
6. 启动 QEMU（TCG 加速、`-no-reboot` 防止三重错误后重启）

退出 QEMU 后查看 `serial.log` 可看到内核启动日志。

### 常用构建参数

```powershell
python build.py --noclean      # 不清缓存，保留 temp/ 加速二次构建
python build.py --kernel-only  # 只重编译内核，跳过应用和库
```

⚠ 不支持 `--noqemu`（`build.py` 第 76 行注释明确"不准使用 --noqemu"）。

### 添加新应用

1. 在 `Apps/` 下新建目录，例如 `Apps/MyApp/`
2. 创建 `App/MyApp/main.py`（参考 `Apps/HelloWorld/main.py`）
3. 创建 `App/MyApp/project.json`（参考 `Apps/HelloWorld/project.json`，注意 `triple = "x86_64-none-elf"`、`linker` 用 `ld.lld` 输出 `.elf`）
4. 在 `build.py` 中追加构建 + 拷贝命令
5. 在 `disk/apps/MyApp/` 目录放应用需要的资源（运行时通过 vpsdk 访问）

### 添加新驱动

在 `VKernel/Kernel/drivers/<子系统>/<设备>/` 下添加 `<设备>.py`，参考 `fs/fat32/fat32.py`（最大的驱动，自研 FAT32 完整实现）。在 `VKernel/Kernel/main.py` 中注册驱动初始化。

### 平台说明

| 平台 | 状态 |
|------|------|
| Windows 10/11 + mingw + QEMU | ✅ 主平台，CI 测试覆盖 |
| Linux x86_64 + clang + QEMU | ⚠ 理论可用，需把 `build.py` 改用 `disk.sh`，ld.lld 用系统 lld |
| macOS | ❌ 未测试 |
| 真实硬件 | ❌ 暂未支持（仅 UEFI x86_64） |

### 调试

- **QEMU 串口日志**：`build.py` 启动时把 `-serial file:serial.log`，所有 `printf` 写到该文件
- **GDB**：`qemu-system-x86_64` 加 `-s -S` 然后用 `gdb` 连 `localhost:1234`
- **崩溃排查**：`build.py` 默认带 `-no-reboot`，避免三重错误后无限重启

### 进一步阅读

- [TransPyC 编译器仓库](https://git.gvsds.com/GVSDS/TransPyC)
- [Viper 语言概览](https://git.gvsds.com/GVSDS/TransPyC/blob/main/wiki/01-overview.md)
- [ViperOS SDK wiki](vpsdk/wiki/01-overview.md)
- [Viper 模板项目（ViperTemplateProject）](https://git.gvsds.com/GVSDS/Viper_TemplateProject)

---

<a id="english"></a>

## English

### What is this

`ViperOS` is the flagship demo of the [Viper](https://git.gvsds.com/GVSDS/TransPyC) language: a **complete bootable operating system** written in Viper. Unlike a Linux distro or a teaching mini-OS, ViperOS uses one language for everything — kernel, device drivers, user programs, libraries, SDK all use Viper (Python syntax + LLVM backend).

Main components:
- **VKernel** — 64-bit microkernel (target `x86_64-none-elf`)
- **UEFI bootloader** — `boot/boot.c` (compiled by GNU-EFI to `disk/EFI/BOOT/bootx64.efi`)
- **FAT32 driver** — self-implemented, supports mount/dir/file operations
- **4 user applications** — HelloWorld / Terminal / Gargantua / Scene3D
- **2 dynamic libraries** — SerialLogger / VPUI64
- **ViperPOS SDK** — user-space development kit (syscall, window, fs, process)

### Directory layout

```
ViperOS/
├── .gitignore              # ignores all output/, temp/, build artifacts
├── build.py                # top-level build entry: build -> pack -> QEMU
├── linker.ld               # top-level linker script
├── boot/                   # UEFI bootloader
│   ├── Makefile
│   └── boot.c
├── VKernel/                # kernel
│   ├── project.json        # kernel build config
│   ├── linker.ld
│   └── Kernel/
│       ├── main.py         # kernel entry
│       ├── bootinfo.py
│       ├── drivers/        # device drivers
│       │   ├── core/cpu/   # APIC, CPU, FPU
│       │   ├── devfs/      # device filesystem
│       │   ├── fs/fat32/   # self-implemented FAT32 driver
│       │   ├── input/      # keyboard, mouse
│       │   ├── serial/     # 8250 UART
│       │   ├── storage/    # IDE
│       │   ├── usb/        # USB HID / UHCI
│       │   └── video/      # VESA framebuffer + UI
│       ├── execrunner/     # ELF loader
│       ├── intr/           # GDT/IDT/ISR/syscall
│       ├── mm/             # memory management
│       ├── paging/         # paging
│       ├── sched/          # coroutine, process, scheduler
│       ├── services/       # kernel services
│       └── platform/       # platform glue (PIC/PIT/RTC/Timer)
├── Apps/                   # user apps (each subdir = one ELF)
│   ├── HelloWorld/
│   ├── Terminal/
│   ├── Gargantua/
│   └── Scene3D/
├── Libs/                   # shared libraries (each subdir = one .so)
│   ├── SerialLogger/
│   └── VPUI64/
├── vpsdk/                  # ViperPOS SDK (for user apps)
│   ├── __init__.py
│   ├── stdlib.py
│   ├── syscall.py
│   ├── window.py
│   ├── vpui.py
│   ├── fs.py
│   ├── process.py
│   ├── dynlib.py
│   └── wiki/               # SDK wiki
├── Scripts/
│   ├── check_disk.py
│   ├── disk.ps1            # ImDisk-based FAT32 image builder
│   └── disk.sh             # Linux-equivalent
└── disk/                   # files packed into disk.img
    ├── EFI/BOOT/bootx64.efi
    ├── app/helloworld.asm
    ├── apps/               # .elf destination (filled at build time)
    ├── libs/               # .so destination (filled at build time)
    └── sys/kernel/x86_64/kernel.bin
```

### Prerequisites

| Tool | Notes |
|------|-------|
| `python` ≥ 3.10 | runs TransPyC |
| `llc` | LLVM static compiler |
| `ld.lld` | LLD linker (bare-metal) |
| `qemu-system-x86_64` | QEMU emulator |
| `imdisk` | Windows disk-image mount utility; on Linux use `disk.sh` instead |
| `gnu-efi` toolchain | builds the UEFI bootloader (`boot/boot.c`) |
| [TransPyC](https://git.gvsds.com/GVSDS/TransPyC) | compiler; **must be cloned as a sibling of ViperOS** |

Required layout:

```
D:\Users\TermiNexus\Desktop\TransPyC\
├── TransPyC\        # compiler repo
├── ViperOS\         # this repo
└── ViperTemplateProject\
```

### Quick start

```powershell
# 1. From the ViperOS directory
cd D:\Users\TermiNexus\Desktop\TransPyC\ViperOS

# 2. Full build and launch QEMU
python build.py

# 3. Serial log is written to serial.log
```

`build.py` automatically:
1. Calls `Projectrans.py` to build VKernel -> `VKernel/output/kernel.bin`
2. Builds 2 shared libraries (SerialLogger, VPUI64)
3. Builds 4 applications (HelloWorld, Terminal, Gargantua, Scene3D)
4. Copies all artifacts into `disk/apps/`, `disk/libs/`, `disk/sys/kernel/x86_64/`
5. Calls `Scripts/disk.ps1` to create a 64MB FAT32 image `disk.img`
6. Launches QEMU (TCG accel, `-no-reboot` to prevent reboot on triple fault)

After quitting QEMU, inspect `serial.log` for kernel boot messages.

### Common build flags

```powershell
python build.py --noclean      # keep temp/ to speed up subsequent builds
python build.py --kernel-only  # only rebuild the kernel, skip apps/libs
```

`--noqemu` is **NOT supported** (see comment at line 76 of `build.py`).

### Adding a new application

1. Create a directory under `Apps/`, e.g. `Apps/MyApp/`
2. Add `App/MyApp/main.py` (see `Apps/HelloWorld/main.py` for reference)
3. Add `App/MyApp/project.json` (see `Apps/HelloWorld/project.json`; set `triple = "x86_64-none-elf"`, link with `ld.lld` to produce `.elf`)
4. Add build + copy commands in `build.py`
5. Put any runtime resources in `disk/apps/MyApp/` (read at runtime via vpsdk)

### Adding a new driver

Add `<device>.py` under `VKernel/Kernel/drivers/<subsystem>/<device>/`. See `fs/fat32/fat32.py` (largest, full FAT32 implementation). Register the init in `VKernel/Kernel/main.py`.

### Platform support

| Platform | Status |
|----------|--------|
| Windows 10/11 + mingw + QEMU | ✅ primary, CI-tested |
| Linux x86_64 + clang + QEMU | ⚠ theoretically works, requires modifying `build.py` to use `disk.sh` and system lld |
| macOS | ❌ untested |
| Real hardware | ❌ not yet (UEFI x86_64 only) |

### Debugging

- **QEMU serial log**: `build.py` passes `-serial file:serial.log`; all `printf` output goes there
- **GDB**: add `-s -S` to `qemu-system-x86_64` and attach `gdb` to `localhost:1234`
- **Crash triage**: `build.py` always uses `-no-reboot`, avoiding reboot loops after triple faults

### Further reading

- [TransPyC compiler](https://git.gvsds.com/GVSDS/TransPyC)
- [Viper language overview](https://git.gvsds.com/GVSDS/TransPyC/blob/main/wiki/01-overview.md)
- [ViperOS SDK wiki](vpsdk/wiki/01-overview.md)
- [Viper template project (ViperTemplateProject)](https://git.gvsds.com/GVSDS/Viper_TemplateProject)