#!/bin/sh
#
# $Id: ifdef,v 1.5 2006/05/15 18:52:45 vogelke Exp $
#
# NAME:
#    ifdef
#
# SYNOPSIS:
#    ifdef [-hv] files
#
# DESCRIPTION:
#    This writes something I can include in a program to tell me what
#    macros were used when compiling.  Handy for things like the TCP
#    wrapper programs, so I can tell if I used -DPARANOID by just
#    doing "strings /usr/etc/tcpd".
#
#    Assumes you have nawk plus a version of cpp that reads from stdin.
#
# OPTIONS:
#    "-h" prints help and exits.
#    "-v" prints the version and exits.
#
# AUTHOR:
#    Karl Vogel <vogelke@pobox.com>
#    Sumaria Systems, Inc.

PATH=/bin:/usr/sbin:/usr/local/bin:/usr/ucb
export PATH

tmp=/tmp/ifdef.tmp.$$
trap "rm -f $tmp; exit 0" 0 1 2 3 15

tag=`basename $0`	# tag for the syslog entries.

# ============================= FUNCTIONS ==================================

die () {
    echo "$tag: ERROR -- $*" >& 2
    exit 1
}

usage () {
    lines=`egrep -n '^# (NAME|AUTHOR)' $0 | cut -f1 -d:`

    (
        case "$#" in
            0)  ;;
            *)  echo "usage error: $*"; echo ;;
        esac

        case "$lines" in
            "") ;;

            *)  set `echo $lines | sed -e 's/ /,/'`
                sed -n ${1}p $0 | sed -e 's/^#//g' |
                    egrep -v AUTHOR:
                ;;
        esac
    ) >& 2

    exit 1
}

version () {
    local_sedscr='s/RCSfile: //
    s/.Date: //
    s/,v . .Revision: /  v/
    s/\$//g'

    local_revno='$RCSfile: ifdef,v $ $Revision: 1.5 $'
    local_revdate='$Date: 2006/05/15 18:52:45 $'
    echo "$local_revno $local_revdate" | sed -e "$local_sedscr"
}

# ============================= MAIN PROGRAM ===============================

#
# Handle command line arguments.
#

set -- `getopt hv $*`

case "$?" in
    0)  ;;
    *)  usage "unrecognized option" ;;
esac

for i in $*
do
    case $i in
        -h) usage ;;
        -v) version; exit 0;;
        --) shift; break;;
    esac
done

#
# Strip non-preprocessor stuff from each input file.
# We want to find lines containing "defined" or "if[n]def", remove
# || or && conditions, and ignore crap like "#ifdef lint".
#

cpp=/usr/ccs/lib/cpp

rmjunk='
s/^defined(//
s/)$//
/^lint$/d
/^LIBC_SCCS$/d
'

for file in $*
do
    sed -e 's/^#/ #/' $file | $cpp -P | sed -e 's/^ #/#/' |
        egrep 'ifdef|ifndef|defined\(' | tr -d '!|&' | fmt -1 |
        grep -v '^#' | sed -e "$rmjunk" >> $tmp
done

#
# Read macro strings from stdin, write lines that look like this to stdout:
#
#   #ifdef something
#   static char  *something_defined = "something is defined";
#   #endif
#
# Break the static char line if it gets too long.
#

date=`date`

sort -u $tmp |
nawk 'BEGIN {
    printf "/* generated by '$tag' on '"$date"' */\n\n"
}
{
    var = $1
    gsub ("_", "", var)
    part1 = sprintf ("static char *%s_defined = ", var)
    part2 = sprintf ("\"%s is defined\";", $1)

    if (length (part1) + length (part2) > 77)
    {
        part1 = sprintf ("static char *%s_defined =\n\t", var)
    }

    printf "#ifdef %s\n", $1
    printf "%s%s\n", part1, part2
    printf "#endif\n\n"
}'

exit 0