# Fast stack [![Build Status](https://travis-ci.org/SamSaffron/fast_stack.svg?branch=master)](https://travis-ci.org/SamSaffron/fast_stack)

Very efficient collection of ruby backtraces, even under heavy CPU load

### How do you use it?

```ruby
require 'fast_stack'
```

### Usage

```ruby
def fib( n )
  return  n  if ( 0..1 ).include? n
  ( fib( n - 1 ) + fib( n - 2 ) )
end

stacks = FastStack.profile do
  fib(30)
end

puts stacks.count # => 30
```

### Notes

This technique was conceived by https://github.com/tmm1 , big thank you.

Ruby 2.0 uses #backtrace_locations, 1.9.3 uses #backtrace

(gem template based on https://github.com/CodeMonkeySteve/fast_xor )


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fast_stack

Sam Saffron

(Experimental) An ambiguous license classifier was found.

What is an ambiguous license classifier?

Ambiguous License Classifier

Source files are encoded using a non-standard text encoding.

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Bad text encoding

Package version is not a valid semantic version (semver).

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Bad semver

Package has dependencies with an invalid semantic version. This could be a sign of beta, low quality, or unmaintained dependencies.

What is bad dependency semver?

Bad dependency semver

Source files contain bidirectional unicode control characters. This could indicate a Trojan source supply chain attack. See: trojansource.codes for more information.

What are bidirectional unicode control characters?

Bidirectional unicode control characters

This package has multiple bin scripts with the same name. This can cause non-deterministic behavior when installing or could be a sign of a supply chain attack.

What is bin script confusion?

Bin script confusion

This Chrome extension includes a content script '{scriptFile}' that runs on websites matching '{matches}'.

What are Chrome extension content scripts?

Chrome Extension Content Script

This Chrome extension requests access to '{host}'.

What are Chrome extension host permissions?

Chrome Extension Host Permission

This Chrome extension uses the '{permission}' permission.

What are Chrome extension permissions?

Chrome Extension Permission

This Chrome extension requests broad access to websites with the pattern '{host}'.

What are Chrome extension wildcard host permissions?

Chrome Extension Wildcard Host Permission

Semantic versions published out of chronological order.

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Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

(Experimental) Copyleft license information was found.

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Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

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Title

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High CVE

Uses debug, reflection and dynamic code execution features.

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Debug access

The maintainer of the package marked it as deprecated. This could indicate that a single version should not be used, or that the package is no longer maintained and any new vulnerabilities will not be fixed.

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Deprecated

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Deprecated SPDX exception

(Experimental) License is deprecated which may have legal implications regarding the package's use.

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Deprecated license

Package name is similar to other popular packages and may not be the package you want.

What is a typosquat?

Possible typosquat attack

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

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Dynamic require

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Empty package

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Environment variable access

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Name

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File dependency

Accesses the file system, and could potentially read sensitive data.

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Filesystem access

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Wildcard dependency

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Git dependency

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GitHub dependency

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Native code

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High entropy strings

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Unicode homoglyphs

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HTTP dependency

Install scripts are run when the package is installed. The majority of malware in npm is hidden in install scripts.

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Install scripts

Package has an invalid manifest file and can cause installation problems if you try to use it.

What is an invalid manifest file?

Invalid manifest file

Source files contain invisible characters. This could indicate source obfuscation or a supply chain attack.

What are invisible characters?

Invisible chars

(Experimental) Package license has recently changed.

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License change

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What is a license exception?

License exception

This package is not allowed per your license policy. Review the package's license to ensure compliance.

What is a license policy violation?

License Policy Violation

Contains long string literals, which may be a sign of obfuscated or packed code.

What's wrong with long strings?

Long strings

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Major refactor

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This package contains minified code. This may be harmless in some cases where minified code is included in packaged libraries, however packages on npm should not minify code.

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The package was published by an npm account that no longer exists.

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Modified license exception

(Experimental) Package contains a modified version of an SPDX license. Please read carefully before using this code.

What is a modified license?

Modified license

What is network access?

Network access

A new npm collaborator published a version of the package for the first time. New collaborators are usually benign additions to a project, but do indicate a change to the security surface area of a package.

What is new author?

New author

Package does not specify a list of contributors or an author in package.json.

Why is contributor and author data important?

No contributors or author data

Package does not have a linked bug tracker in package.json.

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No bug tracker

(Experimental) License information could not be found.

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No README

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Why are missing repositories important?

No repository

Package does not have any tests. This is a strong signal of a poorly maintained or low quality package.

fast_stack

Fast stack

How do you use it?

Usage

Notes

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