#! /bin/sh

# igawk --- like gawk but do @include processing
# Arnold Robbins, arnold@gnu.ai.mit.edu, Public Domain
# July 1993

if [ "$1" = debug ]
then
    set -x
    shift
else
    # cleanup on exit, hangup, interrupt, quit, termination
    trap 'rm -f /tmp/ig.[se].$$' 0 1 2 3 15
fi

while [ $# -ne 0 ] # loop over arguments
do
    case $1 in
    --)     shift; break;;

    -W)     shift
            set -- -W"$@"
            continue;;

    -[vF])  opts="$opts $1 '$2'"
            shift;;

    -[vF]*) opts="$opts '$1'" ;;

    -f)     echo @include "$2" >> /tmp/ig.s.$$
            shift;;

    -f*)    f=`echo "$1" | sed 's/-f//'`
            echo @include "$f" >> /tmp/ig.s.$$ ;;

    -?file=*)    # -Wfile or --file
            f=`echo "$1" | sed 's/-.file=//'`
            echo @include "$f" >> /tmp/ig.s.$$ ;;

    -?file)    # get arg, $2
            echo @include "$2" >> /tmp/ig.s.$$
            shift;;

    -?source=*)    # -Wsource or --source
            t=`echo "$1" | sed 's/-.source=//'`
            echo "$t" >> /tmp/ig.s.$$ ;;

    -?source)  # get arg, $2
            echo "$2" >> /tmp/ig.s.$$
            shift;;

    -?version)
            echo igawk: version 1.0 1>&2
            gawk --version
            exit 0 ;;

    -[W-]*)    opts="$opts '$1'" ;;

    *)      break;;
    esac
    shift
done

if [ ! -s /tmp/ig.s.$$ ]
then
    if [ -z "$1" ]
    then
         echo igawk: no program! 1>&2
         exit 1
    else
        echo "$1" > /tmp/ig.s.$$
        shift
    fi
fi

# at this point, /tmp/ig.s.$$ has the program
gawk -- '
# process @include directives

function pathto(file,    i, t, junk)
{
    if (index(file, "/") != 0)
        return file

    for (i = 1; i <= ndirs; i++) {
        t = (pathlist[i] "/" file)
        if ((getline junk < t) > 0) {
            # found it
            close(t)
            return t
        }
    }
    return ""
}
BEGIN {
    path = ENVIRON["AWKPATH"]
    ndirs = split(path, pathlist, ":")
    for (i = 1; i <= ndirs; i++) {
        if (pathlist[i] == "")
            pathlist[i] = "."
    }
    stackptr = 0
    input[stackptr] = ARGV[1] # ARGV[1] is first file

    for (; stackptr >= 0; stackptr--) {
        while ((getline < input[stackptr]) > 0) {
            if (tolower($1) != "@include") {
                print
                continue
            }
            fpath = pathto($2)
            if (fpath == "") {
                printf("igawk:%s:%d: cannot find %s\n", \
                    input[stackptr], FNR, $2) > "/dev/stderr"
                continue
            }
            if (! (fpath in processed)) {
                processed[fpath] = input[stackptr]
                input[++stackptr] = fpath
            } else
                print $2, "included in", input[stackptr], \
                    "already included in", \
                    processed[fpath] > "/dev/stderr"
        }
        close(input[stackptr])
    }
}' /tmp/ig.s.$$ > /tmp/ig.e.$$
eval gawk -f /tmp/ig.e.$$ $opts -- "$@"

exit $?