configure

#!/bin/sh

PATH=$PATH:/bin:/usr/bin:/usr/sbin:/sbin:/usr/local/sbin

case "$1" in
  --from-dkms-conf*)
    KDKMS=`echo "$1" | sed 's/[^=]*.//'`
    # restore options from existing Makefile, if present
    if [ -e Makefile ]; then
      set -- `sed -n 's/^CARGS = \(.*\)/\1/p' Makefile`
      FROMDKMSCONF=1
    fi
    ;;
esac

error() {
  printf "! Error: $*\n"
  exit 1
}

compiler_presence_test() {
  echo -n "Check for working gcc: "
  $CC -v >/dev/null 2>&1
  if [ $? = 0 ]; then
    echo Yes "($CC)"
  else
    echo No

    echo "! You need gcc to install module from source"
    if [ -s /etc/debian_version ]; then
      NAME=Debian
      if [ -e /etc/os-release ]; then
	. /etc/os-release >/dev/null 2>&1
      fi
      echo "! "
      echo "! Under $NAME try to run this:"
      echo "!   root# apt-get install gcc"
      echo "! "
    elif [ -s /etc/redhat-release ]; then
      echo "! "
      echo "! Under Centos try to run this:"
      echo "!   root# yum install gcc"
      echo "! "
    fi
    exit 1
  fi
}

show_help() {
  echo "Possible options:"
  echo "  --kver=..     kernel version (ex.: 2.6.30-std-def-alt15)"
  echo "  --kdir=..     directory for kernel source (ex.: /usr/src/kernel)"
  echo "  --enable-snmp-rules    enables SNMP-index conversion rules"
  echo "  --enable-macaddress    enables MAC address for v9/IPFIX"
  echo "  --enable-vlan          enables VLAN Ids for v9/IPFIX"
  echo "  --enable-direction     enables flowDirection(61) Element"
  echo "  --enable-sampler       enables Flow Sampling"
  echo "  --enable-sampler=hash  enables Hash sampler"
  echo "  --enable-aggregation   enables aggregation rules"
  echo "  --promisc-mpls         decapsulate MPLS in promisc mode"
  echo "  --promisc-mpls=N       -- and record N labels (default 3)"
  echo "  --enable-physdev       enables physdev reporting"
  echo "  --enable-physdev-override      to override interfaces"
  echo "  --disable-snmp-agent   disables net-snmp agent"
  echo "  --disable-dkms         disables DKMS support completely"
  echo "  --disable-dkms-install  no DKMS install but still create dkms.conf"
  exit 0
}

CARGS="$@"
for ac_option
do
  case "$ac_option" in
    -*=*) ac_optarg=`echo "$ac_option" | sed 's/[-_a-zA-Z0-9]*=//'` ;;
    *) ac_optarg= ;;
  esac

  case "$ac_option" in
    --kver=*)  KVERSION="$ac_optarg" ;;
    --kdir=*)      KDIR="$ac_optarg" ;;
    --enable-mac*)   KOPTS="$KOPTS -DENABLE_MAC" ;;
    --enable-vlan*)  KOPTS="$KOPTS -DENABLE_VLAN" ;;
    --enable-direc*) KOPTS="$KOPTS -DENABLE_DIRECTION" ;;
    --enable-sampl*hash) KOPTS="$KOPTS -DENABLE_SAMPLER -DSAMPLING_HASH" ;;
    --enable-sampl*) KOPTS="$KOPTS -DENABLE_SAMPLER" ;;
    --enable-aggr*)  KOPTS="$KOPTS -DENABLE_AGGR" ;;
    --promisc-mpls*)   ENABLE_PROMISC=1; PROMISC_MPLS=1; MPLS_DEPTH=${ac_optarg:-3} ;;
    --enable-snmp-r*)  KOPTS="$KOPTS -DSNMP_RULES" ;;
    --enable-physdev)       KOPTS="$KOPTS -DENABLE_PHYSDEV" ;;
    --enable-physdev-over*) KOPTS="$KOPTS -DENABLE_PHYSDEV_OVER" ;;
    --disable-snmp-a*)   SKIPSNMP=1 ;;
    --disable-net-snmp*) SKIPSNMP=1 ;;
    --disable-dkms*)     SKIPDKMS=1 ;;
    --from-dkms-conf*) ;;
    --make) echo called from make; CARGS=`echo $CARGS | sed s/--make//g` ;;
    -Werror) KOPTS="$KOPTS -Werror" ;;
    --help|-h) show_help ;;
    -*) echo Invalid option: $ac_option; exit 1 ;;
#    *) ni="$ni $ac_option" ;;
  esac
done

ENABLE_PROMISC=1
if [ "$PROMISC_MPLS" = 1 ]; then
  KOPTS="$KOPTS -DPROMISC_MPLS"
  case "$MPLS_DEPTH" in (*[!0-9]*|"") MPLS_DEPTH=1 ;; esac
  if [ "$MPLS_DEPTH" -lt 1 ]; then
    echo "! Requested MPLS stack depth is too small, limiting to 1."
  elif [ "$MPLS_DEPTH" -gt 10 ]; then
    echo "! Requested MPLS stack depth is too big, limiting to 10."
    MPLS_DEPTH=10;
  fi
  if [ "$MPLS_DEPTH" -ge 1 ]; then KOPTS="$KOPTS -DMPLS_DEPTH=$MPLS_DEPTH"; fi
fi

kernel_find_version() {
  KHOW=requested
  test "$KVERSION" && return 0

  if grep -q '#.*Debian' /proc/version; then
    KHOW=proc
    KVERSION=`sed -n 's/.*#.*Debian \([0-9\.]\+\)-.*/\1/p' /proc/version`
    KLIBMOD=`uname -r`
  else
    KHOW=uname
    KVERSION=`uname -r`
  fi
  test "$KDIR" || return 0

  test -s $KDIR/Makefile || return 1
  test -s $KDIR/include/config/kernel.release || return 1
  KVERSION=`cat $KDIR/include/config/kernel.release`
  KHOW=sources
}

kernel_check_src() {
  if [ -s "$1/Makefile" ]; then
    KDIR="$1"
    return 0
  fi
  return 1
}

kernel_check_src2() {
  if kernel_check_src $1/source; then
    KSRC=$KDIR
  fi
  kernel_check_src $1/build
}

kernel_find_source() {
  if [ "$KDKMS" ]; then
    # dkms args is highest priority
    KDIR=$KDKMS
    KSHOW=dkms
    return 0
  fi
  KSHOW=requested
  test "$KDIR" && return 0
  KSHOW=found
  kernel_check_src2 /lib/modules/$KLIBMOD  && return 0
  kernel_check_src2 /lib/modules/$KVERSION && return 0
  kernel_check_src  /usr/src/kernels/$KVERSION && return 0
  kernel_check_src  /usr/src/linux-$KVERSION && return 0
  echo "! Linux source not found. Don't panic. You may specify kernel source"
  echo "! directory with --kdir=..., or try to install kernel-devel package,"
  echo "! or just raw sources for linux-$KVERSION from kernel.org."
  if grep -q -i centos /proc/version 2>/dev/null; then
    echo "! "
    arch=.`uname -m`
    echo "! Under Centos simply run this:"
    echo "!   root# yum install kernel-devel"
  fi
  if grep -q -i debian /proc/version 2>/dev/null; then
    echo "! "
    echo "! Under Debian simply run this:"
    echo "!   root# apt-get install module-assistant"
    echo "!   root# m-a prepare"
  fi
  exit 1
}

kernel_check_consistency() {
  if [ -s $KDIR/include/config/kernel.release ]; then
    SRCVER=`cat $KDIR/include/config/kernel.release`
    if [ "$KVERSION" != "$SRCVER" ]; then
      echo "! Warning: $KHOW kernel version ($KVERSION) and $KSHOW version of kernel source ($SRCVER) doesn't match!"
      echo "!   You may try to specify only kernel source tree with --kdir=$KDIR"
      echo "!   and configure will pick up version properly."
      echo "! Assuming you want to build for $SRCVER"
      KVERSION=$SRCVER
    fi
  fi
  test -e "$KDIR/.config" || error ".config in kernel source not found, run  make menuconfig  in $KDIR"
  test -d "$KDIR/include/config" || error "kernel is not prepared, run  make prepare modules_prepare  in $KDIR"
}

kconfig() {
  KCONFIG=$KDIR/.config
  if ! grep -q "^$1=" $KCONFIG 2>/dev/null; then
    if [ "$KCONFIGREPORTED" != true ]; then
      KCONFIGREPORTED=true
      echo Kernel config file checked: $KCONFIG
      echo
    fi
    echo "! Attention: $1 is undefined in your kernel configuration"
    echo "!   Without this option enabled $2 will not work."
    echo
    return 1
  fi
  return 0
}

kernel_check_config() {
  kconfig CONFIG_SYSCTL			"sysctl interface"
  kconfig CONFIG_PROC_FS		"proc interface"
  kconfig CONFIG_IPV6			"IPv6"
}

kernel_check_include() {
  echo -n "Checking for presence of $1... "
  if [ "$KSRC" -a -e $KSRC/$1 ]; then
    echo Yes
    KOPTS="$KOPTS $2"
  elif [ -e $KDIR/$1 ]; then
    echo Yes
    KOPTS="$KOPTS $2"
  else
    echo No
  fi
}

kernel_check_features() {
  kernel_check_include include/linux/llist.h -DHAVE_LLIST
  kernel_check_include include/linux/grsecurity.h -DHAVE_GRSECURITY_H
}

snmp_check() {
  SNMPTARGET=
  SNMPINSTALL=
  test "$SKIPSNMP" && return

  echo -n "Searching for net-snmp-config... "
  if which net-snmp-config >/dev/null 2>&1; then
    echo Yes `which net-snmp-config`
  else
    echo No.
    SNMPCONFIG=no
  fi

  echo -n "Searching for net-snmp agent... "
  if [ -s /etc/redhat-release ]; then
    if ! rpm --quiet -q net-snmp; then
      echo No.
      SNMPADD="do:  yum install net-snmp"
      if [ "$SNMPCONFIG" ]; then
	SNMPADD="$SNMPADD net-snmp-devel"
      fi
    else
      echo Yes.
    fi
    if [ "$SNMPCONFIG" ]; then
      SNMPCONFIG="run:  yum install net-snmp-devel"
    fi
  elif [ -s /etc/debian_version ]; then
    if ! dpkg -s snmpd >/dev/null 2>&1; then
      echo No.
      SNMPADD="do:  apt-get install snmpd"
      if [ "$SNMPCONFIG" ]; then
	SNMPADD="$SNMPADD libsnmp-dev"
      fi
    else
      echo Yes.
    fi
    if [ "$SNMPCONFIG" ]; then
      SNMPCONFIG="run:  apt-get install libsnmp-dev"
    fi
  elif [ -s /etc/snmp/snmpd.conf ]; then
    echo Yes.
  else
    echo No.
    SNMPADD="install net-snmp (www.net-snmp.org)"
    SNMPCONFIG="reinstall net-snmp with agent support."
  fi

  if [ "$SNMPADD" ]; then
    echo " Assuming you don't want net-snmp agent support".
    echo " Otherwise $SNMPADD"
    return
  elif [ "$SNMPCONFIG" ]; then
    echo "! You have net-snmp agent but not development package."
    echo "! net-snmp agent will not be built, to fix:"
    echo "!   $SNMPCONFIG"
    return
  fi

  SNMPTARGET=snmp_netflow.so
  SNMPINSTALL=sinstall
}

dkms_check() {
  DKMSINSTALL=
  test "$SKIPDKMS" && return

  echo -n "Checking for DKMS... "
  if ! which dkms >/dev/null 2>&1; then
    echo "No. (It may be useful to install it.)"
    echo "! "
    echo "! DKMS is method of installing kernel modules, that will"
    echo "! automatically recompile module after kernel upgrade."
    if [ -s /etc/debian_version ]; then
      echo "! "
      echo "! To install it under Debian simply run this:"
      echo "!   root# apt-get install dkms"
      echo "! "
    elif [ -s /etc/redhat-release ]; then
      echo "! "
      echo "! To install it under Centos enable EPEL or RPMforge repository,"
      echo "! then run this:"
      echo "!   root# yum install dkms"
      echo "! "
    fi
    return
  fi
  echo Yes.
  DKMSINSTALL=dinstall
  test "$FROMDKMSCONF" && return
  if dkms status | grep ^pkt-netflow, >/dev/null; then
    echo "! You are already have module installed via DKMS"
    echo "!   it will be uninstalled on 'make install' and"
    echo "!   current version of module installed afterwards."
    echo "! Use --disable-dkms option if don't want this."
  fi
}

kernel_find_version	#KVERSION
test "$KLIBMOD" || KLIBMOD=$KVERSION
echo "Kernel version: $KVERSION ($KHOW)"
kernel_find_source	#KDIR
echo "Kernel sources: $KDIR ($KSHOW)"
kernel_check_consistency
kernel_check_config
kernel_check_features

CC=${CC:-gcc}
compiler_presence_test

snmp_check
dkms_check

rm -f compat_def.h

REPLACE="\
s!@CARGS@!$CARGS!;\
s!@KVERSION@!$KVERSION!;\
s!@KDIR@!$KDIR!;\
s!@KOPTS@!$KOPTS!;\
s!@SNMPTARGET@!$SNMPTARGET!;\
s!@SNMPINSTALL@!$SNMPINSTALL!;\
s!@DKMSINSTALL@!$DKMSINSTALL!"

echo -n "Creating Makefile.. "
 sed "$REPLACE" Makefile.in > Makefile
 echo done.
echo
echo "  If you need some options enabled run ./configure --help"
echo "  Now run: make all install"
echo