parser36

A lightweight, dependency-free JavaScript library for parsing, manipulating, and reconstructing r36s dts files.

Overview

Parser36 provides a Proxy-based API that converts complex DTS structures into a manipulatable JavaScript object tree. This allows for programmatic modification of hardware descriptions before stringifying them back into a valid DTS format compatible with the Device Tree Compiler (dtc).

How it Works

1. Tokenization

The parser identifies DTS elements:

• Comments (skipped)
• Directives (e.g., /dts-v1/)
• Labels and Node names
• Properties (Strings, Cells <...>, Bytes [...])

2. AST Construction & Proxy Wrapper

The parseDTS(source) function returns a Proxy-wrapped root node.

• Path Access: dts.get('/path/to/node')
• Search: dts.find('compatible-string')
• Native JS Values: Assign numbers, strings, or arrays directly.

3. Manipulation API

• node.property = value: Update or create a property.
• node.add(name, { props }): Inject new child nodes.
• node.children: Iterate through child nodes.

4. Stringification

• node.toString(): Reconstructs the tree into a clean, properly indented DTS file.

Example Usage

import { readFileSync, writeFileSync } from 'fs';
import { parseDTS } from './parser36.js';

const content = readFileSync('my_device.dts', 'utf8');
const dts = parseDTS(content);

// 1. Modify properties via path
const mmc = dts.get('/dwmmc@ff370000');
if (mmc) {
    mmc.status = 'okay';
    mmc['max-frequency'] = 150000000; // Auto-converts to <0x8f0d180>
}

// 2. Find and update a node by compatible
const panel = dts.find('simple-panel-dsi');
if (panel) {
    panel['dsi,flags'] = [0xe03];
}

// 3. Stringify back to DTS
writeFileSync('updated.dts', dts.toString());

Validation

The tests/test-md5.js script is provided to ensure the parser's stability. It performs a "round-trip" validation (DTS -> AST -> DTS) and verifies that the output remains functionally identical to the input.

Build & Test

Use the root Makefile to run everything:

make        # Patch examples and run tests
make clean  # Remove generated files