# callgraph-py2

**Repository Path**: lbit/callgraph-py2

## Basic Information

- **Project Name**: callgraph-py2
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2026-07-08
- **Last Updated**: 2026-07-08

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# callgraph-py2

Find all callees of a C/C++ function using the **clangd** LSP server.

Since clangd 14 does not implement `callHierarchy/outgoingCalls`, this
tool uses an alternative approach: it locates the target function via
`prepareCallHierarchy`, scans its body for call sites, and resolves each
callee's definition using `textDocument/definition`.

## Architecture

```
src/
├── main.py       # CLI entry point
└── core/         # Core library
    ├── lsp.py    # Generic LSP client (JSON-RPC over stdio)
    ├── clangd.py # Clangd server wrapper (spawn, init, document ops)
    ├── finder.py # Callee finder (body scan + definition resolution)
    └── project.py# Project root auto-detection
```

- **`core/lsp.py`** — A general-purpose LSP client that implements JSON-RPC
  message framing (Content-Length headers), request/response correlation,
  and server-request handling. Works with any LSP server, not just clangd.
- **`core/clangd.py`** — Wraps the LSP client with clangd-specific configuration
  (compile_commands.json path, background indexing, document management).
- **`core/finder.py`** — Uses `prepareCallHierarchy` to obtain the function
  body range, scans the source for call sites (`identifier(`), and
  resolves each callee via `textDocument/definition`. When line/column
  are not provided, locates the function via `documentSymbol`.
- **`project.py`** — Walks up the directory tree to find the project root,
  prioritising `compile_commands.json`.

## Usage

```bash
# Install dependencies (none required — pure stdlib)
cd /home/linux/code/callgraph-py2
uv sync

# Run built-in targets
uv run callgraph-py2 --root /home/linux/code/lynxi-drivers/

# Analyse a single function (auto-locate position)
uv run callgraph-py2 \
    --func lynd_pci_probe \
    --file /home/linux/code/lynxi-drivers/lyn_drv/drivers/pci_host/lynd_pci_host.c

# Analyse with explicit position (1-based line/column)
uv run callgraph-py2 \
    --func lynd_pci_remove \
    --file /home/linux/code/lynxi-drivers/lyn_drv/drivers/pci_host/lynd_pci_host.c \
    --line 1724 --column 1
```

## Output

Each callee is printed with its name, file path, line, and column:

```
============================================================
Function: lynd_pci_remove
  File:   /home/linux/code/lynxi-drivers/lyn_drv/drivers/pci_host/lynd_pci_host.c
  Pos:    line 1724, col 1
  Callees (8):
    lynd_tag  /home/linux/code/lynxi-drivers/.../lynd_pci_host.c:1728:2
    pci_disable_device  /home/linux/code/lynxi-linux/drivers/pci/pci.c:4567:1
    ...
============================================================
```

## Line / Column Convention

Line and column arguments are **1-based** (as displayed in editors).
They are converted to 0-based internally for the LSP protocol.