strace to json parser
Branch: master
Clone or download
dannykopping Merge pull request #6 from dannykopping/parsing-fixes
Parsing fixes, adding new tracer
Latest commit 9ac7092 Feb 12, 2019
Permalink
Type Name Latest commit message Commit time
Failed to load latest commit information.
.circleci Merge branch 'master' of github.com:dannykopping/b3 Feb 11, 2019
lib Adding pegjs-backtrace with test instructions in README Feb 12, 2019
test Handling weird case, simplifying struct Feb 12, 2019
.gitignore Adding build script Feb 11, 2019
CHANGELOG Version bump & CHANGELOG Feb 12, 2019
LICENSE Adding CLI script, dependencies, light refactoring Feb 10, 2019
README.md Adding pegjs-backtrace with test instructions in README Feb 12, 2019
_config.yml Set theme jekyll-theme-cayman Feb 11, 2019
build.sh Improving build script Feb 11, 2019
cli.js Adding trace option and error debug display Feb 11, 2019
grammar.pegjs
package-lock.json
package.json Version bump & CHANGELOG Feb 12, 2019

README.md

B3 CircleCI

Purpose

This project's goal is to parse the famously impenetrable strace output into JSON.

Demo

asciicast

Installation

Using npm: npm i -g b3-strace-parser

or download the latest release

Usage

strace -f -p 1234 |& b3
# The "|&" is a shortcut for "2>&1 |" from Bash 4.0 (pipe stdout AND stderr to next program)

strace outputs to stderr, which is why you need the redirection.

For extra tastiness, combine with jq

strace -f -p 1234 |& b3 | jq '' -c

Tests

Run npm test to execute the test suite.

To enable extra tracing for problem-solving, set TRACE=true

Caveats, Limitations & Other Miscellany

  • Speed-wise, the utility performs well (according to my biased and unscientific benchmarking). It can currently parse ~15-20k lines per second, and there's much room for optimisation I'm sure.
  • The utility cannot handle unfinished syscalls
  • The utility silently skips parsers, unless the -s/--stop-on-fail switch is enabled
  • The utility uses the very excellent peg.js and you should too!

If you encounter any parsing errors, please create an issue and I will be happy to fix it! ...or better yet, be a good FOSS citizen and send an MR :)

Um, why?

Well, that's up to you. I figured that this output is so information-dense that it has to be useful in a structured format.

I love this utility and use it all the time, and wanted to learn more about it.

...plus it was a fun, terrifying, frustrating and illuminating excursion into parsing grammars (but oy vey what a schlep!).

Why not do this in C?

  1. I don't know C well enough, and...
  2. I invite you to examine the glorious mess that is this nearly 30-year old edifice
  3. Many people have tried and failed/given up, and I'm neither smarter nor more persistent than them