Slides from the Berlinsides/SkyTalks Hammer talk
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Meredith L. Patterson
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docs/hammer-presentation.pdf
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docs/hammer-presentation.tex
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\documentclass{beamer}
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\usetheme[secheader]{Boadilla}
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\usecolortheme{seahorse}
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\setbeamertemplate{footline}{https://github.com/UpstandingHackers/hammer}
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\title{Hammer: Smashing Binary Formats Into Bits}
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\author{mlp and tq}
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\date{July 27, 2012}
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\institute[2012]{Upstanding Hackers}
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\usepackage{fancyvrb}
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\usepackage{color}
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\usepackage[utf8]{inputenc}
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\makeatletter
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\def\PY@reset{\let\PY@it=\relax \let\PY@bf=\relax%
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\let\PY@ul=\relax \let\PY@tc=\relax%
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\let\PY@bc=\relax \let\PY@ff=\relax}
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\def\PY@tok#1{\csname PY@tok@#1\endcsname}
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\def\PY@toks#1+{\ifx\relax#1\empty\else%
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\PY@tok{#1}\expandafter\PY@toks\fi}
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\def\PY@do#1{\PY@bc{\PY@tc{\PY@ul{%
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\PY@it{\PY@bf{\PY@ff{#1}}}}}}}
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\def\PY#1#2{\PY@reset\PY@toks#1+\relax+\PY@do{#2}}
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\def\PY@tok@gd{\def\PY@tc##1{\textcolor[rgb]{0.63,0.00,0.00}{##1}}}
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\def\PY@tok@gu{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.50,0.00,0.50}{##1}}}
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\def\PY@tok@gt{\def\PY@tc##1{\textcolor[rgb]{0.00,0.25,0.82}{##1}}}
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\def\PY@tok@gs{\let\PY@bf=\textbf}
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\def\PY@tok@gr{\def\PY@tc##1{\textcolor[rgb]{1.00,0.00,0.00}{##1}}}
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\def\PY@tok@cm{\let\PY@it=\textit\def\PY@tc##1{\textcolor[rgb]{0.25,0.50,0.50}{##1}}}
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\def\PY@tok@vg{\def\PY@tc##1{\textcolor[rgb]{0.10,0.09,0.49}{##1}}}
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\def\PY@tok@m{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@mh{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@go{\def\PY@tc##1{\textcolor[rgb]{0.50,0.50,0.50}{##1}}}
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\def\PY@tok@ge{\let\PY@it=\textit}
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\def\PY@tok@vc{\def\PY@tc##1{\textcolor[rgb]{0.10,0.09,0.49}{##1}}}
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\def\PY@tok@il{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@cs{\let\PY@it=\textit\def\PY@tc##1{\textcolor[rgb]{0.25,0.50,0.50}{##1}}}
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\def\PY@tok@cp{\def\PY@tc##1{\textcolor[rgb]{0.74,0.48,0.00}{##1}}}
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\def\PY@tok@gi{\def\PY@tc##1{\textcolor[rgb]{0.00,0.63,0.00}{##1}}}
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\def\PY@tok@gh{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.00,0.50}{##1}}}
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\def\PY@tok@ni{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.60,0.60,0.60}{##1}}}
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\def\PY@tok@nl{\def\PY@tc##1{\textcolor[rgb]{0.63,0.63,0.00}{##1}}}
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\def\PY@tok@nn{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.00,1.00}{##1}}}
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\def\PY@tok@no{\def\PY@tc##1{\textcolor[rgb]{0.53,0.00,0.00}{##1}}}
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\def\PY@tok@na{\def\PY@tc##1{\textcolor[rgb]{0.49,0.56,0.16}{##1}}}
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\def\PY@tok@nb{\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@nc{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.00,1.00}{##1}}}
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\def\PY@tok@nd{\def\PY@tc##1{\textcolor[rgb]{0.67,0.13,1.00}{##1}}}
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\def\PY@tok@ne{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.82,0.25,0.23}{##1}}}
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\def\PY@tok@nf{\def\PY@tc##1{\textcolor[rgb]{0.00,0.00,1.00}{##1}}}
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\def\PY@tok@si{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.73,0.40,0.53}{##1}}}
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\def\PY@tok@s2{\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PY@tok@vi{\def\PY@tc##1{\textcolor[rgb]{0.10,0.09,0.49}{##1}}}
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\def\PY@tok@nt{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@nv{\def\PY@tc##1{\textcolor[rgb]{0.10,0.09,0.49}{##1}}}
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\def\PY@tok@s1{\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PY@tok@sh{\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PY@tok@sc{\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PY@tok@sx{\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@bp{\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@c1{\let\PY@it=\textit\def\PY@tc##1{\textcolor[rgb]{0.25,0.50,0.50}{##1}}}
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\def\PY@tok@kc{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@c{\let\PY@it=\textit\def\PY@tc##1{\textcolor[rgb]{0.25,0.50,0.50}{##1}}}
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\def\PY@tok@mf{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@err{\def\PY@bc##1{\fcolorbox[rgb]{1.00,0.00,0.00}{1,1,1}{##1}}}
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\def\PY@tok@kd{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@ss{\def\PY@tc##1{\textcolor[rgb]{0.10,0.09,0.49}{##1}}}
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\def\PY@tok@sr{\def\PY@tc##1{\textcolor[rgb]{0.73,0.40,0.53}{##1}}}
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\def\PY@tok@mo{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@kn{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@mi{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@gp{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.00,0.50}{##1}}}
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\def\PY@tok@o{\def\PY@tc##1{\textcolor[rgb]{0.40,0.40,0.40}{##1}}}
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\def\PY@tok@kr{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@s{\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PY@tok@kp{\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@w{\def\PY@tc##1{\textcolor[rgb]{0.73,0.73,0.73}{##1}}}
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\def\PY@tok@kt{\def\PY@tc##1{\textcolor[rgb]{0.69,0.00,0.25}{##1}}}
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\def\PY@tok@ow{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.67,0.13,1.00}{##1}}}
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\def\PY@tok@sb{\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PY@tok@k{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.00,0.50,0.00}{##1}}}
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\def\PY@tok@se{\let\PY@bf=\textbf\def\PY@tc##1{\textcolor[rgb]{0.73,0.40,0.13}{##1}}}
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\def\PY@tok@sd{\let\PY@it=\textit\def\PY@tc##1{\textcolor[rgb]{0.73,0.13,0.13}{##1}}}
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\def\PYZbs{\char`\\}
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\def\PYZus{\char`\_}
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\def\PYZob{\char`\{}
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\def\PYZcb{\char`\}}
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\def\PYZca{\char`\^}
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\def\PYZsh{\char`\#}
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\def\PYZpc{\char`\%}
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\def\PYZdl{\char`\$}
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\def\PYZti{\char`\~}
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% for compatibility with earlier versions
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\def\PYZat{@}
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\def\PYZlb{[}
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\def\PYZrb{]}
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\makeatother
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\begin{document}
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\frame{\titlepage}
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\section[Outline]{}
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\frame{\tableofcontents}
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\section{Introduction}
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\frame{
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\frametitle{The recursive-descent family}
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\begin{itemize}
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\item<1-> Recursive descent parsers
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\begin{itemize}
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\item Parsing like mom used to do it (if your mom is Jack Crenshaw)
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\item Conceptually really simple
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\item Can't do left recursion
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\item Can have exponential runtime
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\end{itemize}
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\item<2-> Parsing expression grammars
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\begin{itemize}
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\item Look a lot like CFGs
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\item Always deterministic (unambiguous)
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\item Provide lookahead
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\item Still can't do left recursion
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\end{itemize}
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\item<3-> Packrat parsers
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\begin{itemize}
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\item They're PEGs, but memoized
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\item Can handle left-recursion!
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\end{itemize}
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\end{itemize}
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}
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\section{Binary Parsing}
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\frame{
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\frametitle{Why binary parsing?}
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\begin{itemize}
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\item<1-> None of the existing tools do it well
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\begin{itemize}
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\item Limited to character streams
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\item Endianness is a pain in the dick
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\item So are bit-fields
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\end{itemize}
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\item<2-> Except bison, which nobody likes
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\begin{itemize}
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\item Interface sucks for everything except parsers/interpreters
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\item Shift-reduce conflicts are confusing
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\item Bit-fields still hard unless everything's nicely byte-aligned
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\end{itemize}
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\end{itemize}
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}
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\frame{
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\frametitle{Requirements}
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\begin{itemize}
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\item Thread-safe and reentrant
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\item Simple API
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\item Fast
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\item Correct
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\end{itemize}
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}
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\section{Parser combinators}
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\frame{
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\frametitle{Naming conventions}
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\begin{itemize}
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\item<1-> Types
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\begin{itemize}
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\item Start with \textbf{H} and are CamelCased
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\item \texttt{HParser}, \texttt{HParsedToken}, etc
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\end{itemize}
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\item<2-> Functions
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\begin{itemize}
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\item Start with \textbf{h\_} and use underscores
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\item \texttt{h\_parse()}, \texttt{h\_length\_value()}, etc
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\end{itemize}
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\end{itemize}
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}
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\begin{frame}[fragile]
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\frametitle{Basic usage}
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\begin{Verbatim}[commandchars=\\\{\}]
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\PY{c+cp}{\PYZsh{}}\PY{c+cp}{include "hammer.h"}
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\PY{k}{const} \PY{n}{HParsedToken}\PY{o}{*} \PY{n+nf}{build\PYZus{}my\PYZus{}struct}\PY{p}{(}\PY{k}{const} \PY{n}{HParseResult} \PY{o}{*}\PY{n}{p}\PY{p}{)} \PY{p}{\PYZob{}}
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\PY{c+c1}{// ...}
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\PY{p}{\PYZcb{}}
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\PY{k+kt}{int} \PY{n+nf}{main}\PY{p}{(}\PY{k+kt}{int} \PY{n}{argc}\PY{p}{,} \PY{k+kt}{char}\PY{o}{*}\PY{o}{*} \PY{n}{argv}\PY{p}{)} \PY{p}{\PYZob{}}
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\PY{c+c1}{// obtain data, and its length, from somewhere}
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\PY{c+c1}{// Create a parser}
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\PY{n}{HParser} \PY{o}{*}\PY{n}{parser} \PY{o}{=} \PY{n}{action}\PY{p}{(}\PY{p}{.}\PY{p}{.}\PY{p}{.}\PY{p}{,}
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\PY{n}{build\PYZus{}my\PYZus{}struct}\PY{p}{)}\PY{p}{;}
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\PY{c+c1}{// Parse the data}
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\PY{n}{HParseResult} \PY{o}{*}\PY{n}{result} \PY{o}{=} \PY{n}{h\PYZus{}parse}\PY{p}{(}\PY{n}{parser}\PY{p}{,} \PY{n}{data}\PY{p}{,} \PY{n}{length}\PY{p}{)}\PY{p}{;}
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\PY{c+c1}{// Get your struct back from the result token and use it}
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\PY{n}{do\PYZus{}something}\PY{p}{(}\PY{n}{result}\PY{o}{-}\PY{o}{>}\PY{n}{ast}\PY{o}{-}\PY{o}{>}\PY{n}{user}\PY{p}{)}\PY{p}{;}
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\PY{k}{return} \PY{l+m+mi}{0}\PY{p}{;}
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\PY{p}{\PYZcb{}}
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\end{Verbatim}
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\end{frame}
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\begin{frame}[fragile]
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\frametitle{Result types}
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\begin{itemize}
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\item<1-> HParseResult
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\begin{itemize}
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\item A tree of parsed tokens
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\item The total number of bits parsed
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\item A reference to the memory context for this parse
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\end{itemize}
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\item<2-> HParsedToken
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\begin{itemize}
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\item Token type: bytes, signed/unsigned int, sequence, user-defined
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\item Token (a tagged union)
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\item Byte index and bit offset
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\end{itemize}
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\end{itemize}
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\end{frame}
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\begin{frame}[fragile]
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\frametitle{Primitives}
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\begin{itemize}
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\item<1-> Character and token parsers
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\begin{itemize}
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\item \texttt{h\_ch(const uint8\_t c)}, \\ \texttt{h\_token(const uint8\_t *str, size\_t len)}
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\item \texttt{h\_ch\_range(const uint8\_t lower, const uint8\_t upper)}
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\item \texttt{h\_not\_in(const uint8\_t charset, size\_t length)}
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\end{itemize}
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\item<2-> Integral parsers
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\begin{itemize}
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\item \texttt{h\_uint8()}, \texttt{h\_int64()}
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\item \texttt{h\_bits(size\_t len, bool sign)}
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\item \texttt{h\_int\_range(const HParser *p, const int64\_t lower, const int64\_t upper)}
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\end{itemize}
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\item<3-> End-of-input
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\begin{itemize}
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\item \texttt{h\_end\_p()}
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\end{itemize}
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\end{itemize}
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\end{frame}
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\begin{frame}[fragile]
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\frametitle{Combining primitives}
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\begin{itemize}
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\item<1-> Sequential and alternative
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\begin{itemize}
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\item \texttt{h\_sequence(const HParser *p, ...)}
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\item \texttt{h\_choice(const HParser *p, ...)}
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\end{itemize}
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\item<2-> Repetition
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\begin{itemize}
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\item \texttt{h\_many(const HParser *p)}
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\item \texttt{h\_many1(const HParser *p)}
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\item \texttt{h\_repeat\_n(const HParser *p, size\_t len)}
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\end{itemize}
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\item<3-> Optional
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\begin{itemize}
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\item \texttt{h\_optional(const HParser *p)}
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\end{itemize}
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\item<4-> Not Actually Appearing In This Parse Tree
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\begin{itemize}
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\item \texttt{h\_ignore(const HParser *p)}
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\end{itemize}
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\item<5-> Higher-order
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\begin{itemize}
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\item \texttt{h\_length\_value(const HParser *length, const HParser *value)}
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\item \texttt{h\_and(const HParser *p)}, \texttt{h\_not(const HParser *p)}
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\item \texttt{h\_indirect(const HParser *p)}
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\end{itemize}
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\end{itemize}
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\end{frame}
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\begin{frame}[fragile]
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\frametitle{Doing things to combinations of primitives}
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\begin{itemize}
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\item<1-> \texttt{h\_attr\_bool(const HParser *p, const HPredicate pred)}
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\item<2-> \texttt{h\_action(const HParser *p, const HAction a)}
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\end{itemize}
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\end{frame}
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\section{A practical example}
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\begin{frame}[fragile]
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\frametitle{Top-level DNS}
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\begin{Verbatim}[commandchars=\\\{\}]
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\PY{k}{const} \PY{n}{HParser} \PY{o}{*}\PY{n}{dns\PYZus{}message} \PY{o}{=}
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\PY{n}{h\PYZus{}action}\PY{p}{(}\PY{n}{h\PYZus{}attr\PYZus{}bool}\PY{p}{(}\PY{n}{h\PYZus{}sequence}\PY{p}{(}\PY{n}{dns\PYZus{}header}\PY{p}{,}
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\PY{n}{h\PYZus{}many}\PY{p}{(}\PY{n}{dns\PYZus{}question}\PY{p}{)}\PY{p}{,}
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\PY{n}{h\PYZus{}many}\PY{p}{(}\PY{n}{dns\PYZus{}rr}\PY{p}{)}\PY{p}{,}
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\PY{n}{h\PYZus{}end\PYZus{}p}\PY{p}{(}\PY{p}{)}\PY{p}{,}
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\PY{n+nb}{NULL}\PY{p}{)}\PY{p}{,}
|
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\PY{n}{validate\PYZus{}dns}\PY{p}{)}\PY{p}{,}
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\PY{n}{pack\PYZus{}dns\PYZus{}struct}\PY{p}{)}\PY{p}{;}
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|
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\end{Verbatim}
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\end{frame}
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\begin{frame}[fragile]
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\frametitle{DNS Questions}
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\begin{Verbatim}[commandchars=\\\{\}]
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\PY{k}{const} \PY{n}{HParser} \PY{o}{*}\PY{n}{dns\PYZus{}question} \PY{o}{=}
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\PY{n}{h\PYZus{}sequence}\PY{p}{(}\PY{n}{h\PYZus{}sequence}\PY{p}{(}\PY{n}{h\PYZus{}many1}\PY{p}{(}\PY{n}{h\PYZus{}length\PYZus{}value}\PY{p}{(}\PY{n}{h\PYZus{}int\PYZus{}range}\PY{p}{(}
|
||||
\PY{n}{h\PYZus{}uint8}\PY{p}{(}\PY{p}{)}\PY{p}{,}
|
||||
\PY{l+m+mi}{1}\PY{p}{,}
|
||||
\PY{l+m+mi}{255}\PY{p}{)}\PY{p}{,}
|
||||
\PY{n}{h\PYZus{}uint8}\PY{p}{(}\PY{p}{)}\PY{p}{)}\PY{p}{)}\PY{p}{,}
|
||||
\PY{n}{h\PYZus{}ch}\PY{p}{(}\PY{l+s+sc}{'\PYZbs{}x00'}\PY{p}{)}\PY{p}{,}
|
||||
\PY{n+nb}{NULL}\PY{p}{)}\PY{p}{,} \PY{c+c1}{// QNAME}
|
||||
\PY{n}{qtype}\PY{p}{,} \PY{c+c1}{// QTYPE}
|
||||
\PY{n}{qclass}\PY{p}{,} \PY{c+c1}{// QCLASS}
|
||||
\PY{n+nb}{NULL}\PY{p}{)}\PY{p}{;}
|
||||
|
||||
\end{Verbatim}
|
||||
\end{frame}
|
||||
|
||||
\begin{frame}[fragile]
|
||||
\frametitle{DNS RRs}
|
||||
\begin{Verbatim}[commandchars=\\\{\}]
|
||||
\PY{k}{const} \PY{n}{HParser} \PY{o}{*}\PY{n}{dns\PYZus{}rr} \PY{o}{=}
|
||||
\PY{n}{h\PYZus{}sequence}\PY{p}{(}\PY{n}{domain}\PY{p}{,} \PY{c+c1}{// NAME}
|
||||
\PY{n}{type}\PY{p}{,} \PY{c+c1}{// TYPE}
|
||||
\PY{n}{class}\PY{p}{,} \PY{c+c1}{// CLASS}
|
||||
\PY{n}{h\PYZus{}uint32}\PY{p}{(}\PY{p}{)}\PY{p}{,} \PY{c+c1}{// TTL}
|
||||
\PY{c+c1}{// RDLENGTH+RDATA}
|
||||
\PY{n}{h\PYZus{}length\PYZus{}value}\PY{p}{(}\PY{n}{h\PYZus{}uint16}\PY{p}{(}\PY{p}{)}\PY{p}{,} \PY{n}{h\PYZus{}uint8}\PY{p}{(}\PY{p}{)}\PY{p}{)}\PY{p}{,}
|
||||
\PY{n+nb}{NULL}\PY{p}{)}\PY{p}{;}
|
||||
|
||||
\end{Verbatim}
|
||||
\end{frame}
|
||||
|
||||
\begin{frame}[fragile]
|
||||
\frametitle{Validating a DNS packet}
|
||||
\begin{Verbatim}[commandchars=\\\{\}]
|
||||
\PY{n}{bool} \PY{n+nf}{validate\PYZus{}dns}\PY{p}{(}\PY{n}{HParseResult} \PY{o}{*}\PY{n}{p}\PY{p}{)} \PY{p}{\PYZob{}}
|
||||
\PY{k}{if} \PY{p}{(}\PY{n}{TT\PYZus{}SEQUENCE} \PY{o}{!}\PY{o}{=} \PY{n}{p}\PY{o}{-}\PY{o}{>}\PY{n}{ast}\PY{o}{-}\PY{o}{>}\PY{n}{token\PYZus{}type}\PY{p}{)}
|
||||
\PY{k}{return} \PY{n+nb}{false}\PY{p}{;}
|
||||
\PY{n}{HParsedToken} \PY{o}{*}\PY{o}{*}\PY{n}{elems} \PY{o}{=} \PY{n}{p}\PY{o}{-}\PY{o}{>}\PY{n}{ast}\PY{o}{-}\PY{o}{>}\PY{n}{seq}\PY{o}{-}\PY{o}{>}\PY{n}{elements}\PY{p}{[}\PY{l+m+mi}{0}\PY{p}{]}\PY{o}{-}\PY{o}{>}\PY{n}{seq}\PY{o}{-}\PY{o}{>}
|
||||
\PY{n}{elements}\PY{p}{;}
|
||||
\PY{k+kt}{size\PYZus{}t} \PY{n}{qd} \PY{o}{=} \PY{n}{elems}\PY{p}{[}\PY{l+m+mi}{8}\PY{p}{]}\PY{o}{-}\PY{o}{>}\PY{n}{uint}\PY{p}{;}
|
||||
\PY{k+kt}{size\PYZus{}t} \PY{n}{an} \PY{o}{=} \PY{n}{elems}\PY{p}{[}\PY{l+m+mi}{9}\PY{p}{]}\PY{o}{-}\PY{o}{>}\PY{n}{uint}\PY{p}{;}
|
||||
\PY{k+kt}{size\PYZus{}t} \PY{n}{ns} \PY{o}{=} \PY{n}{elems}\PY{p}{[}\PY{l+m+mi}{10}\PY{p}{]}\PY{o}{-}\PY{o}{>}\PY{n}{uint}\PY{p}{;}
|
||||
\PY{k+kt}{size\PYZus{}t} \PY{n}{ar} \PY{o}{=} \PY{n}{elems}\PY{p}{[}\PY{l+m+mi}{11}\PY{p}{]}\PY{o}{-}\PY{o}{>}\PY{n}{uint}\PY{p}{;}
|
||||
\PY{n}{HParsedToken} \PY{o}{*}\PY{n}{questions} \PY{o}{=} \PY{n}{p}\PY{o}{-}\PY{o}{>}\PY{n}{ast}\PY{o}{-}\PY{o}{>}\PY{n}{seq}\PY{o}{-}\PY{o}{>}\PY{n}{elements}\PY{p}{[}\PY{l+m+mi}{1}\PY{p}{]}\PY{p}{;}
|
||||
\PY{k}{if} \PY{p}{(}\PY{n}{questions}\PY{o}{-}\PY{o}{>}\PY{n}{seq}\PY{o}{-}\PY{o}{>}\PY{n}{used} \PY{o}{!}\PY{o}{=} \PY{n}{qd}\PY{p}{)}
|
||||
\PY{k}{return} \PY{n+nb}{false}\PY{p}{;}
|
||||
\PY{n}{HParsedToken} \PY{o}{*}\PY{n}{rrs} \PY{o}{=} \PY{n}{p}\PY{o}{-}\PY{o}{>}\PY{n}{ast}\PY{o}{-}\PY{o}{>}\PY{n}{seq}\PY{o}{-}\PY{o}{>}\PY{n}{elements}\PY{p}{[}\PY{l+m+mi}{2}\PY{p}{]}\PY{p}{;}
|
||||
\PY{k}{if} \PY{p}{(}\PY{n}{an}\PY{o}{+}\PY{n}{ns}\PY{o}{+}\PY{n}{ar} \PY{o}{!}\PY{o}{=} \PY{n}{rrs}\PY{o}{-}\PY{o}{>}\PY{n}{seq}\PY{o}{-}\PY{o}{>}\PY{n}{used}\PY{p}{)}
|
||||
\PY{k}{return} \PY{n+nb}{false}\PY{p}{;}
|
||||
\PY{k}{return} \PY{n+nb}{true}\PY{p}{;}
|
||||
\PY{p}{\PYZcb{}}
|
||||
|
||||
\end{Verbatim}
|
||||
\end{frame}
|
||||
|
||||
\section{Future work}
|
||||
|
||||
\begin{frame}[fragile]
|
||||
\frametitle{What's next?}
|
||||
\begin{itemize}
|
||||
\item More parsing backends
|
||||
\begin{itemize}
|
||||
\item LL(k)
|
||||
\item GLR
|
||||
\item LALR(8)
|
||||
\item Derivatives
|
||||
\end{itemize}
|
||||
\item Benchmarking :)
|
||||
\item Bindings for python, ruby, (your preferred language here)
|
||||
\end{itemize}
|
||||
\end{frame}
|
||||
|
||||
\begin{frame}[fragile]
|
||||
\frametitle{More to come!}
|
||||
\begin{itemize}
|
||||
\item Watch langsec-discuss@lists.langsec.org for further announcements
|
||||
\item https://github.com/UpstandingHackers/hammer
|
||||
\end{itemize}
|
||||
\end{frame}
|
||||
|
||||
\end{document}
|
||||
Loading…
Add table
Add a link
Reference in a new issue