mirror of
https://github.com/m1ngsama/TNT.git
synced 2026-02-08 00:54:03 +00:00
docs: reorganize documentation structure
- Move all documentation to docs/ directory for better organization - Rewrite README.md following Linux kernel style (English only) - Rename HACKING -> CONTRIBUTING.md - Rename QUICKREF -> QUICKREF.md - Rename README -> README.old - Add comprehensive Development-Guide.md for contributors Documentation structure: - README.md: Project overview and quick start - docs/Development-Guide.md: Complete developer manual - docs/CONTRIBUTING.md: Contribution guidelines - docs/DEPLOYMENT.md: Production deployment guide - docs/SECURITY_QUICKREF.md: Security config reference - docs/QUICKREF.md: Command cheat sheet This aligns with Linux kernel documentation practices: simple, organized, and accessible.
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README.md
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README.md
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@ -1,114 +1,277 @@
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# TNT
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# TNT - Terminal Network Talk
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Terminal chat server. Vim-style interface. SSH-based.
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A minimalist terminal chat server with Vim-style interface over SSH.
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## Install
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## Features
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- **Zero config** - Download and run, auto-generates SSH keys
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- **SSH-based** - Leverage mature SSH protocol for encryption and auth
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- **Vim-style UI** - Modal editing (INSERT/NORMAL/COMMAND)
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- **UTF-8 native** - Full Unicode support
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- **High performance** - Pure C, multi-threaded, sub-100ms startup
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- **Secure** - Rate limiting, auth failure protection, input validation
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- **Persistent** - Auto-saves chat history
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- **Elegant** - Flicker-free TUI rendering
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## Quick Start
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### Installation
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**One-liner:**
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```sh
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curl -sSL https://raw.githubusercontent.com/m1ngsama/TNT/main/install.sh | sh
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```
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Or download from [releases](https://github.com/m1ngsama/TNT/releases).
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**From source:**
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```sh
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git clone https://github.com/m1ngsama/TNT.git
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cd TNT
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make
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sudo make install
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```
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## Run
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**Binary releases:**
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https://github.com/m1ngsama/TNT/releases
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### Running
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```sh
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tnt # port 2222
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tnt # default port 2222
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tnt -p 3333 # custom port
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PORT=3333 tnt # env var
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PORT=3333 tnt # via env var
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```
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Connect: `ssh -p 2222 localhost`
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**Anonymous Access**: By default, users can connect with ANY username and ANY password (or empty password). No SSH keys required. This makes TNT perfect for public chat servers.
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## Security
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Configure via environment variables.
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### Access Control
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### Connecting
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```sh
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TNT_ACCESS_TOKEN="secret" tnt # require password
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TNT_BIND_ADDR=127.0.0.1 tnt # localhost only
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ssh -p 2222 localhost
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```
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Without `TNT_ACCESS_TOKEN`, server is open (default).
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**Anonymous access by default**: Users can connect with ANY username/password (or empty password). No SSH keys required. Perfect for public chat servers.
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### Rate Limiting
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## Usage
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### Keybindings
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**INSERT mode (default)**
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```
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ESC - Enter NORMAL mode
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Enter - Send message
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Backspace - Delete character
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Ctrl+W - Delete last word
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Ctrl+U - Delete line
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Ctrl+C - Enter NORMAL mode
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```
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**NORMAL mode**
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```
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i - Return to INSERT mode
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: - Enter COMMAND mode
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j/k - Scroll down/up
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g/G - Scroll to top/bottom
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? - Show help
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```
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**COMMAND mode**
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```
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:list, :users, :who - Show online users
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:help, :commands - Show available commands
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:clear, :cls - Clear command output
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ESC - Return to NORMAL mode
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```
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### Security Configuration
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**Access control:**
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```sh
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# Require password
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TNT_ACCESS_TOKEN="secret" tnt
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# Bind to localhost only
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TNT_BIND_ADDR=127.0.0.1 tnt
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# Bind to specific IP
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TNT_BIND_ADDR=192.168.1.100 tnt
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```
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**Rate limiting:**
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```sh
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# Max total connections (default 64)
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TNT_MAX_CONNECTIONS=100 tnt
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# Max connections per IP (default 5)
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TNT_MAX_CONN_PER_IP=10 tnt
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# Disable rate limiting (testing only)
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TNT_RATE_LIMIT=0 tnt
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```
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**SSH logging:**
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```sh
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# 0=none, 1=warning, 2=protocol, 3=packet, 4=functions (default 1)
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TNT_SSH_LOG_LEVEL=3 tnt
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```
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**Production example:**
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```sh
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TNT_ACCESS_TOKEN="strong-password-123" \
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TNT_BIND_ADDR=0.0.0.0 \
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TNT_MAX_CONNECTIONS=200 \
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TNT_MAX_CONN_PER_IP=3 \
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TNT_SSH_LOG_LEVEL=1 \
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tnt -p 2222
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```
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## Development
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### Building
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```sh
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TNT_MAX_CONNECTIONS=100 tnt # total limit
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TNT_MAX_CONN_PER_IP=10 tnt # per-IP limit
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TNT_RATE_LIMIT=0 tnt # disable (testing only)
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make # standard build
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make debug # debug build (with symbols)
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make asan # AddressSanitizer build
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make check # static analysis (cppcheck)
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make clean # clean build artifacts
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```
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Default: 64 total, 5 per IP, rate limiting enabled.
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### SSH Options
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### Testing
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```sh
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TNT_SSH_LOG_LEVEL=3 tnt # verbose logging (0-4)
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make test # run comprehensive test suite
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# Individual tests
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cd tests
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./test_basic.sh # basic functionality
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./test_security_features.sh # security features
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./test_anonymous_access.sh # anonymous access
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./test_stress.sh # stress test
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```
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## Keys
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**Test coverage:**
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- Basic functionality: 3 tests
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- Anonymous access: 2 tests
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- Security features: 11 tests
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- Stress test: concurrent connections
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**INSERT** (default)
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- `ESC` → NORMAL
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- `Enter` → send
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- `Backspace` → delete
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### Dependencies
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**NORMAL**
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- `i` → INSERT
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- `:` → COMMAND
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- `j/k` → scroll
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- `g/G` → top/bottom
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- `?` → help
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- **libssh** (>= 0.9.0) - SSH protocol library
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- **pthread** - POSIX threads
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- **gcc/clang** - C11 compiler
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**COMMAND**
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- `:list` → users
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- `:help` → commands
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- `ESC` → back
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**Ubuntu/Debian:**
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```sh
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sudo apt-get install libssh-dev
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```
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## Build
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**macOS:**
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```sh
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brew install libssh
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```
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**Fedora/RHEL:**
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```sh
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sudo dnf install libssh-devel
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```
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## Project Structure
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```
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TNT/
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├── src/ # source code
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│ ├── main.c # entry point
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│ ├── ssh_server.c # SSH server implementation
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│ ├── chat_room.c # chat room logic
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│ ├── message.c # message persistence
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│ ├── tui.c # terminal UI rendering
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│ └── utf8.c # UTF-8 character handling
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├── include/ # header files
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├── tests/ # test scripts
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├── docs/ # documentation
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├── scripts/ # operational scripts
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├── Makefile # build configuration
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└── README.md # this file
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```
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## Deployment
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### systemd Service
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```sh
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make # normal
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make debug # with symbols
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make asan # sanitizer
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make check # static analysis
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sudo cp tnt.service /etc/systemd/system/
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sudo systemctl daemon-reload
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sudo systemctl enable tnt
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sudo systemctl start tnt
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```
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Requires: `libssh`
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### Docker
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## Deploy
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```dockerfile
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FROM alpine:latest
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RUN apk add --no-cache libssh
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COPY tnt /usr/local/bin/
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EXPOSE 2222
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CMD ["tnt"]
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```
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See [DEPLOYMENT.md](DEPLOYMENT.md) for systemd setup.
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See [docs/DEPLOYMENT.md](docs/DEPLOYMENT.md) for details.
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## Files
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```
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messages.log chat history
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host_key SSH key (auto-gen)
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tnt.service systemd unit
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messages.log - Chat history (RFC3339 format)
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host_key - SSH host key (auto-generated, 4096-bit RSA)
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tnt.service - systemd service unit
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```
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## Test
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## Documentation
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```sh
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make test # run comprehensive test suite
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# Individual tests are in tests/ directory
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```
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- [Development Guide](https://github.com/m1ngsama/TNT/wiki/Development-Guide) - Complete development manual
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- [Quick Setup](docs/EASY_SETUP.md) - 5-minute deployment guide
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- [Security Reference](docs/SECURITY_QUICKREF.md) - Security config quick reference
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- [Contributing](docs/CONTRIBUTING.md) - How to contribute
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- [Changelog](docs/CHANGELOG.md) - Version history
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- [CI/CD](docs/CICD.md) - Continuous integration setup
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- [Quick Reference](docs/QUICKREF.md) - Command cheat sheet
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## Docs
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## Performance
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- `README` - man page style
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- `EASY_SETUP.md` - 🚀 **快速部署指南 / Quick Setup Guide**
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- `HACKING` - dev guide
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- `DEPLOYMENT.md` - production
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- `CICD.md` - automation
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- `QUICKREF` - cheat sheet
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- **Startup**: < 100ms (even with 100k+ message history)
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- **Memory**: ~2MB (idle)
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- **Concurrency**: Supports 100+ concurrent connections
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- **Throughput**: 1000+ messages/second
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## Known Limitations
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- Single chat room (no multi-room support yet)
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- Keeps only last 100 messages in memory
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- Ctrl+W only recognizes ASCII space as word boundary
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## Contributing
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Contributions welcome! See [CONTRIBUTING.md](docs/CONTRIBUTING.md)
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**Process:**
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1. Fork the repository
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2. Create feature branch (`git checkout -b feature/AmazingFeature`)
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3. Commit changes (`git commit -m 'Add some AmazingFeature'`)
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4. Push to branch (`git push origin feature/AmazingFeature`)
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5. Open Pull Request
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## License
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MIT
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MIT License - see [LICENSE](LICENSE)
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## Acknowledgments
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- [libssh](https://www.libssh.org/) - SSH protocol implementation
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- Linux kernel community - Code style and engineering practices
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## Contact
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||||
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- Issues: https://github.com/m1ngsama/TNT/issues
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- Pull Requests: https://github.com/m1ngsama/TNT/pulls
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|
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---
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**"Talk is cheap. Show me the code."** - Linus Torvalds
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585
docs/Development-Guide.md
Normal file
585
docs/Development-Guide.md
Normal file
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# TNT Development Guide
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Complete guide for TNT developers and contributors.
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## Table of Contents
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1. [Architecture Overview](#architecture-overview)
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2. [Code Structure](#code-structure)
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3. [Building and Testing](#building-and-testing)
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4. [Core Components](#core-components)
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5. [Adding Features](#adding-features)
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6. [Debugging](#debugging)
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7. [Performance Optimization](#performance-optimization)
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8. [Contributing Guidelines](#contributing-guidelines)
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---
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## Architecture Overview
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TNT uses a multi-threaded architecture with a main accept loop and per-client threads.
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```
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┌─────────────────────────────────────────────────────────┐
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│ Main Thread │
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│ ┌──────────────────────────────────────────────────┐ │
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│ │ ssh_server_start() │ │
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│ │ └─> ssh_bind_accept() │ │
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│ │ └─> Event loop (auth + channel setup) │ │
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│ │ └─> pthread_create(client_thread) │ │
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│ └──────────────────────────────────────────────────┘ │
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└─────────────────────────────────────────────────────────┘
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│
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┌─────────────────┴─────────────────┐
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│ │
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┌───────▼────────┐ ┌────────▼───────┐
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│ Client Thread 1│ │ Client Thread N│
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│ ┌──────────┐ │ │ ┌──────────┐ │
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│ │ Session │ │ ... │ │ Session │ │
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│ │ Handler │ │ │ │ Handler │ │
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│ └──────────┘ │ │ └──────────┘ │
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└────────────────┘ └────────────────┘
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│ │
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└───────────┬───────────────────────┘
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│
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┌──────────▼──────────┐
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│ Chat Room │
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│ ┌──────────────┐ │
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│ │ RW Lock │ │
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│ │ Clients[] │ │
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│ │ Messages[] │ │
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│ └──────────────┘ │
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└─────────────────────┘
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```
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### Key Design Principles
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1. **Fixed-size buffers** - No dynamic allocation in hot paths
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2. **Reader-writer locks** - Multiple readers, single writer
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3. **Reference counting** - Prevent use-after-free
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4. **Ring buffer** - Fixed-size message history (last 100 messages)
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---
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## Code Structure
|
||||
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### Source Files
|
||||
|
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```
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src/
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├── main.c - Entry point, signal handling
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├── ssh_server.c - SSH server, client threads, authentication
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├── chat_room.c - Chat room logic, message broadcasting
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├── message.c - Message persistence (RFC3339 format)
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├── tui.c - Terminal UI rendering (ANSI escape codes)
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└── utf8.c - UTF-8 character handling
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```
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### Header Files
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||||
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```
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include/
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├── common.h - Common definitions, constants
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├── ssh_server.h - SSH server interface
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├── chat_room.h - Chat room interface
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├── message.h - Message structure and persistence
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||||
├── tui.h - TUI rendering functions
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└── utf8.h - UTF-8 utilities
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```
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### Key Data Structures
|
||||
|
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#### `client_t` (ssh_server.h)
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```c
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typedef struct client {
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ssh_session session;
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ssh_channel channel;
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char username[MAX_USERNAME_LEN];
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int width, height; // Terminal dimensions
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client_mode_t mode; // INSERT/NORMAL/COMMAND
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int scroll_pos;
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bool connected;
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int ref_count; // Reference counting
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pthread_mutex_t ref_lock;
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} client_t;
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```
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|
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#### `chat_room_t` (chat_room.h)
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```c
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typedef struct {
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pthread_rwlock_t lock; // Reader-writer lock
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struct client **clients; // Dynamic array
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int client_count;
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message_t *messages; // Ring buffer
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int message_count;
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} chat_room_t;
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```
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#### `message_t` (message.h)
|
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```c
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typedef struct {
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time_t timestamp;
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char username[MAX_USERNAME_LEN];
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char content[MAX_MESSAGE_LEN];
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} message_t;
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```
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||||
|
||||
---
|
||||
|
||||
## Building and Testing
|
||||
|
||||
### Build Targets
|
||||
|
||||
```sh
|
||||
make # Standard release build
|
||||
make debug # Debug build with symbols (-g)
|
||||
make asan # AddressSanitizer build
|
||||
make check # Static analysis (cppcheck)
|
||||
make clean # Clean build artifacts
|
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make install # Install to /usr/local/bin
|
||||
```
|
||||
|
||||
### Compiler Flags
|
||||
|
||||
**Release build:**
|
||||
```
|
||||
-Wall -Wextra -O2 -std=c11 -D_XOPEN_SOURCE=700
|
||||
```
|
||||
|
||||
**Debug build:**
|
||||
```
|
||||
-Wall -Wextra -g -O0 -std=c11 -D_XOPEN_SOURCE=700
|
||||
```
|
||||
|
||||
**ASAN build:**
|
||||
```
|
||||
-Wall -Wextra -g -O0 -fsanitize=address -fno-omit-frame-pointer
|
||||
```
|
||||
|
||||
### Running Tests
|
||||
|
||||
```sh
|
||||
make test # Run all tests
|
||||
|
||||
# Individual tests
|
||||
cd tests
|
||||
./test_basic.sh # Basic functionality
|
||||
./test_security_features.sh # Security checks
|
||||
./test_anonymous_access.sh # Anonymous access
|
||||
./test_stress.sh # Concurrent connections
|
||||
```
|
||||
|
||||
### Test Coverage
|
||||
|
||||
- **Basic**: Server startup, SSH connection, message logging
|
||||
- **Security**: RSA keys, env vars, UTF-8 validation, buffer overflow protection
|
||||
- **Anonymous**: Passwordless access, any username
|
||||
- **Stress**: 10 concurrent clients for 30 seconds
|
||||
|
||||
---
|
||||
|
||||
## Core Components
|
||||
|
||||
### 1. SSH Server (ssh_server.c)
|
||||
|
||||
**Callback-based API** (libssh 0.9+):
|
||||
|
||||
```c
|
||||
/* Authentication callbacks */
|
||||
static int auth_password(ssh_session session, const char *user,
|
||||
const char *password, void *userdata);
|
||||
static int auth_none(ssh_session session, const char *user, void *userdata);
|
||||
|
||||
/* Channel callbacks */
|
||||
static ssh_channel channel_open_request_session(ssh_session session, void *userdata);
|
||||
static int channel_pty_request(ssh_session session, ssh_channel channel,
|
||||
const char *term, int width, int height,
|
||||
int pxwidth, int pxheight, void *userdata);
|
||||
static int channel_shell_request(ssh_session session, ssh_channel channel,
|
||||
void *userdata);
|
||||
static int channel_exec_request(ssh_session session, ssh_channel channel,
|
||||
const char *command, void *userdata);
|
||||
```
|
||||
|
||||
**Event loop:**
|
||||
```c
|
||||
ssh_event event = ssh_event_new();
|
||||
ssh_event_add_session(event, session);
|
||||
|
||||
/* Wait for: auth_success, channel != NULL, channel_ready */
|
||||
while ((!ctx->auth_success || ctx->channel == NULL || !ctx->channel_ready) && !timed_out) {
|
||||
ssh_event_dopoll(event, 1000);
|
||||
}
|
||||
```
|
||||
|
||||
### 2. Chat Room (chat_room.c)
|
||||
|
||||
**Thread-safe broadcasting:**
|
||||
```c
|
||||
void room_broadcast(chat_room_t *room, const message_t *msg) {
|
||||
pthread_rwlock_wrlock(&room->lock);
|
||||
|
||||
/* Copy client list with ref counting */
|
||||
client_t **clients_copy = calloc(...);
|
||||
for (int i = 0; i < count; i++) {
|
||||
clients_copy[i]->ref_count++;
|
||||
}
|
||||
|
||||
pthread_rwlock_unlock(&room->lock); // Release lock early
|
||||
|
||||
/* Render outside lock (avoid deadlock) */
|
||||
for (int i = 0; i < count; i++) {
|
||||
tui_render_screen(clients_copy[i]);
|
||||
client_release(clients_copy[i]);
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
**Why this works:**
|
||||
- Copy client list while holding write lock
|
||||
- Increment reference counts
|
||||
- Release lock BEFORE rendering
|
||||
- Render to all clients outside lock
|
||||
- Decrement reference counts (may free clients)
|
||||
|
||||
### 3. Message Persistence (message.c)
|
||||
|
||||
**Log format:**
|
||||
```
|
||||
2024-01-13T10:30:45Z|username|message content
|
||||
```
|
||||
|
||||
**Optimized loading** (backward scan):
|
||||
```c
|
||||
/* Scan backwards from file end */
|
||||
fseek(fp, 0, SEEK_END);
|
||||
long file_size = ftell(fp);
|
||||
long pos = file_size - 1;
|
||||
|
||||
/* Read 4KB chunks backwards */
|
||||
#define CHUNK_SIZE 4096
|
||||
while (pos >= 0 && newlines_found < max_messages) {
|
||||
/* Read chunk */
|
||||
/* Count newlines backwards */
|
||||
/* Stop when max_messages found */
|
||||
}
|
||||
```
|
||||
|
||||
**Complexity:** O(last N messages) instead of O(file size)
|
||||
|
||||
### 4. TUI Rendering (tui.c)
|
||||
|
||||
**Flicker-free rendering:**
|
||||
```c
|
||||
/* Move to top (no clear screen!) */
|
||||
pos += snprintf(buffer + pos, size - pos, ANSI_HOME);
|
||||
|
||||
/* Render each line with line clear */
|
||||
for (each line) {
|
||||
pos += snprintf(buffer + pos, size - pos, "%s\033[K\r\n", line);
|
||||
}
|
||||
```
|
||||
|
||||
**ANSI codes:**
|
||||
- `\033[H` - HOME (move cursor to 0,0)
|
||||
- `\033[K` - EL (erase to end of line)
|
||||
- `\033[2J` - ED (erase display) - **DON'T USE** (causes flicker)
|
||||
|
||||
### 5. UTF-8 Handling (utf8.c)
|
||||
|
||||
**Character width:**
|
||||
```c
|
||||
int utf8_char_width(const char *str) {
|
||||
unsigned char c = (unsigned char)str[0];
|
||||
|
||||
/* ASCII */
|
||||
if (c < 0x80) return 1;
|
||||
|
||||
/* CJK ranges (width = 2) */
|
||||
uint32_t codepoint = /* decode UTF-8 */;
|
||||
if (codepoint >= 0x4E00 && codepoint <= 0x9FFF) return 2; // CJK Unified
|
||||
if (codepoint >= 0x3040 && codepoint <= 0x30FF) return 2; // Hiragana/Katakana
|
||||
if (codepoint >= 0xAC00 && codepoint <= 0xD7AF) return 2; // Hangul
|
||||
|
||||
return 1;
|
||||
}
|
||||
```
|
||||
|
||||
**Word deletion (Ctrl+W):**
|
||||
```c
|
||||
void utf8_remove_last_word(char *str) {
|
||||
int i = strlen(str);
|
||||
|
||||
/* Skip trailing spaces */
|
||||
while (i > 0 && str[i-1] == ' ') i--;
|
||||
|
||||
/* Skip non-spaces (the word) */
|
||||
while (i > 0 && str[i-1] != ' ') i--;
|
||||
|
||||
str[i] = '\0';
|
||||
}
|
||||
```
|
||||
|
||||
**Note:** Only recognizes ASCII space as word boundary (not ideal for CJK).
|
||||
|
||||
---
|
||||
|
||||
## Adding Features
|
||||
|
||||
### Adding a New Command
|
||||
|
||||
1. **Add to `execute_command()` in ssh_server.c:**
|
||||
```c
|
||||
if (strcmp(cmd, "newcmd") == 0) {
|
||||
pos += snprintf(output + pos, sizeof(output) - pos,
|
||||
"New command output\n");
|
||||
}
|
||||
```
|
||||
|
||||
2. **Update help text in tui.c:**
|
||||
```c
|
||||
"AVAILABLE COMMANDS:\n"
|
||||
" newcmd - Description of new command\n"
|
||||
```
|
||||
|
||||
3. **Add test in tests/test_basic.sh:**
|
||||
```sh
|
||||
echo ":newcmd" | timeout 5 ssh -p $PORT localhost
|
||||
```
|
||||
|
||||
### Adding a New Keybinding
|
||||
|
||||
1. **Add to `handle_key()` in ssh_server.c:**
|
||||
```c
|
||||
case MODE_INSERT:
|
||||
if (key == 26) { /* Ctrl+Z */
|
||||
/* Handle Ctrl+Z */
|
||||
return true;
|
||||
}
|
||||
```
|
||||
|
||||
2. **Update help text in tui.c**
|
||||
|
||||
3. **Document in README.md**
|
||||
|
||||
---
|
||||
|
||||
## Debugging
|
||||
|
||||
### Enable Verbose SSH Logging
|
||||
|
||||
```sh
|
||||
TNT_SSH_LOG_LEVEL=4 ./tnt
|
||||
```
|
||||
|
||||
Levels:
|
||||
- 0 = No logs
|
||||
- 1 = Warnings (default)
|
||||
- 2 = Protocol
|
||||
- 3 = Packet
|
||||
- 4 = Functions
|
||||
|
||||
### Use AddressSanitizer
|
||||
|
||||
```sh
|
||||
make asan
|
||||
ASAN_OPTIONS=detect_leaks=1 ./tnt
|
||||
```
|
||||
|
||||
Detects:
|
||||
- Buffer overflows
|
||||
- Use-after-free
|
||||
- Memory leaks
|
||||
- Stack corruption
|
||||
|
||||
### Use Valgrind
|
||||
|
||||
```sh
|
||||
make
|
||||
valgrind --leak-check=full --show-leak-kinds=all ./tnt
|
||||
```
|
||||
|
||||
### GDB Debugging
|
||||
|
||||
```sh
|
||||
make debug
|
||||
gdb ./tnt
|
||||
|
||||
(gdb) run
|
||||
(gdb) bt # backtrace on crash
|
||||
(gdb) p var # print variable
|
||||
```
|
||||
|
||||
### Common Issues
|
||||
|
||||
**Problem:** Client disconnects immediately
|
||||
**Solution:** Check `handle_pty_request()` - must wait for shell/exec request
|
||||
|
||||
**Problem:** Rendering flickers
|
||||
**Solution:** Use `\033[K` (line clear) instead of `\033[2J` (screen clear)
|
||||
|
||||
**Problem:** Race condition / deadlock
|
||||
**Solution:** Check lock order, use reader-writer locks correctly
|
||||
|
||||
**Problem:** Memory leak
|
||||
**Solution:** Run with ASAN, check reference counting
|
||||
|
||||
---
|
||||
|
||||
## Performance Optimization
|
||||
|
||||
### Hot Paths
|
||||
|
||||
1. **Message broadcasting** (`room_broadcast`)
|
||||
- Minimize lock holding time
|
||||
- Render outside lock
|
||||
- Use fixed-size buffers
|
||||
|
||||
2. **TUI rendering** (`tui_render_screen`)
|
||||
- Build buffer completely, then single write
|
||||
- No incremental writes
|
||||
- Use `snprintf` (not `strcat`)
|
||||
|
||||
3. **Message loading** (`message_load`)
|
||||
- Backward scan from file end
|
||||
- 4KB chunked reads
|
||||
- Early termination
|
||||
|
||||
### Profiling
|
||||
|
||||
```sh
|
||||
# Compile with profiling
|
||||
make CFLAGS="-pg"
|
||||
|
||||
# Run
|
||||
./tnt
|
||||
|
||||
# Generate report
|
||||
gprof tnt gmon.out > profile.txt
|
||||
```
|
||||
|
||||
### Benchmarking
|
||||
|
||||
```sh
|
||||
# Message throughput
|
||||
time (for i in {1..1000}; do echo "msg $i"; done | ssh -p 2222 localhost)
|
||||
|
||||
# Concurrent connections
|
||||
./tests/test_stress.sh
|
||||
|
||||
# Startup time with large log
|
||||
dd if=/dev/zero of=messages.log bs=1M count=10
|
||||
time ./tnt
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Contributing Guidelines
|
||||
|
||||
### Code Style
|
||||
|
||||
Follow **Linux kernel coding style**:
|
||||
|
||||
```c
|
||||
/* Function brace on new line */
|
||||
int function(int arg)
|
||||
{
|
||||
/* Use tabs (width 8) */
|
||||
if (condition) {
|
||||
/* Do something */
|
||||
}
|
||||
|
||||
/* Single exit point preferred */
|
||||
return ret;
|
||||
}
|
||||
```
|
||||
|
||||
**Rules:**
|
||||
- Tabs for indentation (8 spaces)
|
||||
- Max 80 columns
|
||||
- No trailing whitespace
|
||||
- `/* C-style comments */` (not `//`)
|
||||
- Functions < 100 lines
|
||||
- Max 3 levels of indentation
|
||||
|
||||
### Commit Messages
|
||||
|
||||
```
|
||||
subsystem: short description (max 50 chars)
|
||||
|
||||
Longer explanation if needed (wrap at 72 chars).
|
||||
Explain WHAT and WHY, not HOW.
|
||||
|
||||
- Bullet points OK
|
||||
- Reference issues: Fixes #123
|
||||
|
||||
Signed-off-by: Your Name <email@example.com>
|
||||
```
|
||||
|
||||
Examples:
|
||||
```
|
||||
ssh: migrate to callback-based API
|
||||
|
||||
Replace deprecated message-based API with modern callback-based
|
||||
server implementation. Eliminates message loop complexity.
|
||||
|
||||
tui: optimize rendering to eliminate flicker
|
||||
|
||||
Use ANSI HOME + line clear instead of full screen clear.
|
||||
Reduces rendering time from 50ms to <1ms.
|
||||
```
|
||||
|
||||
### Pull Request Process
|
||||
|
||||
1. **Fork and branch**
|
||||
```sh
|
||||
git checkout -b feature/amazing-feature
|
||||
```
|
||||
|
||||
2. **Make changes**
|
||||
- Write code
|
||||
- Add tests
|
||||
- Update docs
|
||||
|
||||
3. **Test**
|
||||
```sh
|
||||
make clean
|
||||
make
|
||||
make test
|
||||
make asan # must pass!
|
||||
```
|
||||
|
||||
4. **Commit**
|
||||
```sh
|
||||
git commit -s -m "subsystem: description"
|
||||
```
|
||||
|
||||
5. **Push and PR**
|
||||
```sh
|
||||
git push origin feature/amazing-feature
|
||||
# Open PR on GitHub
|
||||
```
|
||||
|
||||
### Code Review Checklist
|
||||
|
||||
- [ ] Follows Linux kernel code style
|
||||
- [ ] All tests pass (`make test`)
|
||||
- [ ] ASAN clean (`make asan`)
|
||||
- [ ] No compiler warnings
|
||||
- [ ] Documentation updated
|
||||
- [ ] Commit messages follow convention
|
||||
- [ ] No unnecessary complexity
|
||||
- [ ] Thread-safe if touching shared data
|
||||
|
||||
---
|
||||
|
||||
## Additional Resources
|
||||
|
||||
- [libssh Documentation](https://api.libssh.org/stable/)
|
||||
- [Linux Kernel Coding Style](https://www.kernel.org/doc/html/latest/process/coding-style.html)
|
||||
- [ANSI Escape Codes](https://en.wikipedia.org/wiki/ANSI_escape_code)
|
||||
- [UTF-8 Specification](https://en.wikipedia.org/wiki/UTF-8)
|
||||
|
||||
---
|
||||
|
||||
**Questions?** Open an issue or discussion on GitHub.
|
||||
Loading…
Reference in a new issue