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C Yacc Lex Makefile
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/*---------------------------------------------------------------------------*/ /* YaccViso - a tool for visualizing dependencies of nonterminals in a yacc */ /* grammar file */ /* Copyright (C) 1997 Leon Aaron Kaplan, email: email@example.com */ /* This program is free software; you can redistribute it and/or modify */ /* it under the terms of the GNU General Public License as published by */ /* the Free Software Foundation; either version 2 of the License, or */ /* (at your option) any later version. */ /* */ /* This program is distributed in the hope that it will be useful, */ /* but WITHOUT ANY WARRANTY; without even the implied warranty of */ /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ /* GNU General Public License for more details. */ /* */ /* You should have received a copy of the GNU General Public License */ /* along with this program; if not, write to the Free Software */ /* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* ----------------------------------------------- end of legal stuff ------ */ /* file: README * YACCVISO * author: L. Aaron Kaplan, firstname.lastname@example.org * date: * last mod.: * descr.: */ TABLE OF CONTENTS ================= 1. COPYRIGHT 2. What is YaccViso 3. Why YaccViso 4. Requirements 5. Where to obtain YaccViso 6. Installation 7. Documentation 8. Systems On Which Yaccviso Was Tested 1. COPYRIGHT ============= This product is copylefted by the GNU General Public License (GPL). You should have received a copy of the GPL along with this program. It is in the file COPYRIGHT. 2. WHAT IS YACCVISO? ==================== Note: throughout this file when I refer to "yacc" I mean both yacc and bison. YaccViso is a tool for visualizing dependencies of non terminal and terminal symbols in a yacc grammar. If you do not know what yacc is then you probably won't need YaccViso. It is thus a tool specifically designed for people who write compilers with yacc who work on large grammar files. YaccViso will take a yacc or bison file, parse it and produce two dependency graphs: one which can be visualized using VCG and one which can be visualized using dot. What do I mean by dependency? If you have a yacc file of the form: %% start : declarations code ; declarations : declarations declaration ; code : code statement ; . . . %% then YaccViso will generate a directed graph in which there are directed edges from "start" to "declarations" and "code", etc. In other words: the rule "start" depends upon "declarations" and "code" 3. WHY YACCVISO? ================ If you have ever written a large grammar such as the grammar for ANSI C with more than 50 productions then you will have noticed that it isn't easy to keep track on each terminal or non terminal symbol, what it does etc. In such a case I recommend using YaccViso and printing your dependency graph of your grammar as a huge poster so that you have a handy reference. What's more: as YaccViso generates an easily parsable output of a directed graph, all the standard algorithms can be applied to this graph and questions such as "which grammar symbol is used in only one context and in which context?" can be answered automatically. We plan to incorporate some of these algorithms into YaccViso when time permits. 4. REQUIREMENTS =============== YaccViso should be compilable on any UN*X system which has: * bison or yacc (tested on both) * flex 2.5.4 or higher * GNU make (See Note gmake) * GNU C compiler (gcc). The Code should be highly portable except for the flex file. I seldomly used any system specific calls except malloc, free, fprintf and exit. In addition you will need one or more of: 1. VCG ("Visualization of compiler graphs") by Georg Sander obtainable at: ftp://ftp.cs.uni-sb-de/pub/graphics/vcg 2. the graphviz package (contains dot, lefty, neato, dotty) by AT&T obtainable at: http://www.research.att.com:80/~north/graphviz/ For the actual visualization. I highly recommend using dot as it produces a more aesthetic layout and as it is faster than VCG. NOTE gmake: The Makefile uses a few lines of conditionals. It was found that these won't work on BSD make and OSF/1 make. Use GNU make (gmake) instead or look at the Makefile and adapt it (it is a small Makefile) and remove theses conditionals. 5. WHERE TO OBTAIN YACCVISO? ============================ Get it from my Web page: https://github.com/aaronkaplan/yaccviso. (I appreciate git pull requests in case you find any errors). 6. INSTALLATION =============== 1) make a unique temporary directory 2) copy the .tgz file into that directory 3) ungzip it and untar it. Now you should have a directory structure like tmpdir |- README (this file) |- src/ |- misc/ |- doc/ |- examples/ 4) Go into the directory src/ and type "gmake" 5) ignore any warnings 6) you should have an executable "yaccviso". Take it and copy it to any location that you want to have it. 7. DOCUMENTATION ================ The documentation in the directory doc/ is far from complete. It gives some insight however. 8. SYSTEMS ON WHICH YACCVISO WAS TESTED ======================================= Redhat Linux 4.2, Pentium 166 DEC OSF/1, DEC Alpha