configure.sh

   1 #!/usr/bin/env bash
   2 #
   3 # Configure.sh  Generates interactively a config.h from config.in
   4 #
   5 # net-tools     A collection of programs that form the base set of the
   6 #               NET-3 Networking Distribution for the LINUX operating
   7 #               system.
   8 #
   9 # Usage:        Install.sh [--nobackup] [--test]
  10 #
  11 # Version:      Install.sh 1.65 (1996-01-12)
  12 #
  13 # Authors:      Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  14 #               Johannes Grosen, <grosen@argv.cs.ndsu.nodak.edu>
  15 #               Copyright 1988-1993 MicroWalt Corporation
  16 #
  17 # Modified:
  18 #        {1.65} Bernd eckes Eckenfels <net-tools@lina.inka.de>
  19 #               some layout cleanups, slattach/plipconfig removed.
  20 #               --test for testinstallations added.
  21 #
  22 #               This program is free software; you can redistribute it
  23 #               and/or  modify it under  the terms of  the GNU General
  24 #               Public  License as  published  by  the  Free  Software
  25 #               Foundation;  either  version 2 of the License, or  (at
  26 #               your option) any later version.
  27 #
  28 #
  29 # Make sure we're really running bash.
  30 #
  31 # I would really have preferred to write this script in a language with
  32 # better string handling, but alas, bash is the only scripting language
  33 # that I can be reasonable sure everybody has on their Linux machine.
  34 #
  35
  36 CONFIG=config.h
  37 MAKECONFIG=config.make
  38
  39
  40 [ -z "$BASH" ] && { echo "Configure requires bash" 1>&2; exit 1; }
  41
  42 # Disable filename globbing once and for all.
  43 # Enable function cacheing.
  44 set -f -h
  45
  46 # set up reading of config file
  47 if [ "$#" != "1" ] || [ ! -f "$1" ]; then
  48         echo "usage: $0 configfile" 1>&2
  49         exit 1
  50 fi
  51 exec 7<$1
  52 config_fd_redir='<&7'
  53
  54 #
  55 # readln reads a line into $ans.
  56 #
  57 #       readln prompt default
  58 #
  59 function readln()
  60 {
  61   echo -n "$1"
  62   IFS='@' read ans || exit 1
  63   [ -z "$ans" ] && ans=$2
  64 }
  65
  66 # bool processes a boolean argument
  67 #
  68 #       bool tail
  69 #
  70 function bool()
  71 {
  72   # Slimier hack to get bash to rescan a line.
  73   eval "set -- $1"
  74   ans=""
  75   while [ "$ans" != "y" -a "$ans" != "n" ]
  76   do
  77         readln "$1 ($2) [$3] " "$3"
  78   done
  79   if [ "$ans" = "y" ]; then
  80         echo "#define $2 1" >>${CONFIG}
  81         echo "$2=1" >>${MAKECONFIG}
  82     else
  83         echo "#define $2 0" >>${CONFIG}
  84         echo "# $2=0" >> ${MAKECONFIG}
  85   fi
  86   raw_input_line="bool '$1' $2 $ans"
  87   eval "$2=$ans"
  88 }
  89
  90 # int processes an integer argument
  91 #
  92 #       int tail
  93 #
  94 function int()
  95 {
  96   # Slimier hack to get bash to rescan a line.
  97   eval "set -- $1"
  98   ans="x"
  99   while [ $[$ans+0] != "$ans" ];
 100   do
 101         readln "$1 ($2) [$3] " "$3"
 102   done
 103   echo "#define $2 ($ans)" >>${CONFIG}
 104   raw_input_line="int '$1' $2 $ans"
 105   eval "$2=$ans"
 106 }
 107
 108   #
 109   # Make sure we start out with a clean slate.
 110   #
 111   > config.new
 112   > ${CONFIG}
 113   > ${MAKECONFIG}
 114
 115   stack=''
 116   branch='t'
 117
 118   while IFS='@' eval read raw_input_line ${config_fd_redir}
 119   do
 120         # Slimy hack to get bash to rescan a line.
 121         read cmd rest <<-END_OF_COMMAND
 122                 $raw_input_line
 123         END_OF_COMMAND
 124
 125         if [ "$cmd" = "*" ]; then
 126                 if [ "$branch" = "t" ]; then
 127                         echo "$raw_input_line"
 128                         # echo "# $rest" >>$CONFIG
 129                         if [ "$prevcmd" != "*" ]; then
 130                                 echo >>${CONFIG}
 131                                 echo "/* $rest" >>${CONFIG}
 132                         else
 133                                 echo " * $rest" >>${CONFIG}
 134                         fi
 135                         prevcmd="*"
 136                 fi
 137         else
 138                 [ "$prevcmd" = "*" ] && echo " */" >>${CONFIG}
 139                 prevcmd=""
 140                 case "$cmd" in
 141                 =)      [ "$branch" = "t" ] && echo "$rest" >>${CONFIG};;
 142                 :)      [ "$branch" = "t" ] && echo "$raw_input_line" ;;
 143                 int)    [ "$branch" = "t" ] && int "$rest" ;;
 144                 bool)   [ "$branch" = "t" ] && bool "$rest" ;;
 145                 exec)   [ "$branch" = "t" ] && ( sh -c "$rest" ) ;;
 146                 if)     stack="$branch $stack"
 147                         if [ "$branch" = "t" ] && eval "$rest"; then
 148                                 branch=t
 149                         else
 150                                 branch=f
 151                         fi ;;
 152                 else)   if [ "$branch" = "t" ]; then
 153                                 branch=f
 154                         else
 155                                 read branch rest <<-END_OF_STACK
 156                                         $stack
 157                                 END_OF_STACK
 158                         fi ;;
 159                 fi)     [ -z "$stack" ] && echo "Error!  Extra fi." 1>&2
 160                         read branch stack <<-END_OF_STACK
 161                                 $stack
 162                         END_OF_STACK
 163                         ;;
 164                 esac
 165         fi
 166         echo "$raw_input_line" >>config.new
 167   done
 168   [ "$prevcmd" = "*" ] && echo " */" >>${CONFIG}
 169
 170   [ -z "$stack" ] || echo "Error!  Unterminated if." 1>&2
 171
 172   mv config.new config.status
 173   exit 0