#!/bin/bash

prog="netstat"

# Pretty that we're the shell and that this command could not be
# found.
if [ "$FAKE_NETSTAT_NOT_FOUND" = "yes" ] ; then
    echo "sh: ${prog}: command not found" >&2
    exit 127
fi

usage ()
{
    cat >&2 <<EOF
Usage: $prog [ -t | --unix ] [ -n ] [ -a ] [ -l ]

A fake netstat stub that prints items depending on the variables
FAKE_NETSTAT_TCP_ESTABLISHED, FAKE_TCP_LISTEN,
FAKE_NETSTAT_UNIX_LISTEN, depending on command-line options.

Note that -n is ignored.

EOF
    exit 1
}

# Defaults.
tcp=false
unix=false
all=false
listen=false

parse_options ()
{
    # $POSIXLY_CORRECT means that the command passed to onnode can
    # take options and getopt won't reorder things to make them
    # options to this script.
    _temp=$(POSIXLY_CORRECT=1 getopt -n "$prog" -o "tnalh" -l unix -l help -- "$@")

    [ $? != 0 ] && usage

    eval set -- "$_temp"

    while true ; do
	case "$1" in
	    -n) shift ;;
	    -a) all=true ; shift ;;
	    -t) tcp=true ; shift ;;
	    -l) listen=true ; shift ;;
	    --unix) unix=true ; shift ;;
	    --) shift ; break ;;
	    -h|--help|*) usage ;; # * shouldn't happen, so this is reasonable.
	esac
    done

    [ $# -gt 0 ] && usage

    # If neither -t or --unix specified then print all.
    $tcp || $unix || { tcp=true ; unix=true ; }
}

parse_options "$@"

if $tcp ; then
    if $listen ; then
	echo "Active Internet connections (servers only)"
    elif $all ; then
	echo "Active Internet connections (servers and established)"
    else
	echo "Active Internet connections (w/o servers)"
    fi

    echo "Proto Recv-Q Send-Q Local Address           Foreign Address         State"

    tcp_fmt="tcp        0      0 %-23s %-23s %s\n"
    for i in $FAKE_NETSTAT_TCP_ESTABLISHED ; do
	src="${i%|*}"
	dst="${i#*|}"
	printf "$tcp_fmt" $src $dst "ESTABLISHED"
    done
    while read src dst ; do
	printf "$tcp_fmt" $src $dst "ESTABLISHED"
    done <"$FAKE_NETSTAT_TCP_ESTABLISHED_FILE"

    if $all || $listen ; then
	for i in $FAKE_TCP_LISTEN ; do
	    printf "$tcp_fmt" $i "0.0.0.0:*" "LISTEN"
	done
    fi
fi

if $unix ; then
    if $listen ; then
	echo "Active UNIX domain sockets (servers only)"
    elif $all ; then
	echo "Active UNIX domain sockets (servers and established)"
    else
	echo "Active UNIX domain sockets (w/o servers)"
    fi
    
    echo "Proto RefCnt Flags       Type       State         I-Node   Path"

    unix_fmt="unix  2      [ ACC ]     STREAM     LISTENING     %-8d %s\n"
    if $all || $listen ; then
	for i in $FAKE_NETSTAT_UNIX_LISTEN ; do
	    printf "$unix_fmt" 12345 "$i"
	done
    fi
fi