#!/bin/bash
# The purpose of this script is to check for all external tools, headers, and
# libraries VBox OSE depends on.

#
# Copyright (C) 2006 InnoTek Systemberatung GmbH
#
# This file is part of VirtualBox Open Source Edition (OSE), as
# available from http://www.virtualbox.org. This file is free software;
# you can redistribute it and/or modify it under the terms of the GNU
# General Public License as published by the Free Software Foundation,
# in version 2 as it comes in the "COPYING" file of the VirtualBox OSE
# distribution. VirtualBox OSE is distributed in the hope that it will
# be useful, but WITHOUT ANY WARRANTY of any kind.
#
# If you received this file as part of a commercial VirtualBox
# distribution, then only the terms of your commercial VirtualBox
# license agreement apply instead of the previous paragraph.
#

LC_ALL=C
export LC_ALL

#
# Defaults
#
OSE=1
WITH_XPCOM=1
WITH_LIBIDL=1
WITH_QT=1
WITH_SDL_TTF=1
CC="gcc"
CXX="g++"
BCC="bcc"
YASM="yasm"
IASL="iasl"
AS86="as86"
XSLTPROC="xsltproc"
GENISOIMAGE="genisoimage"
MKISOFS="mkisofs"
INCXALAN=""
LIBXALAN="-lxalan-c"
INCXERCES=""
LIBXERCES="-lxerces-c"
INCSDL="/usr/include/SDL"
LIBSDL="-lSDL"
LIBSDLMAIN="-lSDLmain"
LIBCRYPTO="-lcrypto"
LIBPTHREAD="-lpthread"
LIBX11="-L/usr/X11R6/lib -lXext -lX11"
LIBXCURSOR="-lXcursor"
INCZ=""
LIBZ="-lz"
INCPNG=""
LIBPNG="-lpng"
QTDIR="/usr/qt/3 /usr/lib/qt3 /usr/lib/qt-3.3 /usr/share/qt3"
KBUILDDIR="`cd $(dirname $0); pwd`/kBuild"
DEVDIR="`cd $(dirname $0); pwd`/tools"
if [ -d /lib/modules/`uname -r`/build ]; then
 LINUX="/lib/modules/`uname -r`/build"
else
 LINUX="/usr/src/linux"
fi
KCHMVIEWER="kchmviewer"
LOG="configure.log"
CNF="AutoConfig.kmk"
ENV="env.sh"
BUILD_TYPE="release"
# the restricting tool is ar (mri mode).
INVALID_CHARS="[^A-Za-z0-9/\\$:._-]"

if (cd $(dirname $0); pwd)|grep -q "$INVALID_CHARS"; then
  echo "Error: VBox base path contains invalid characters!"
  exit 1
fi

function cleanup()
{
  rm -f .tmp_src.cc .tmp_src.c .tmp_out .test_execute.log
}

function fail()
{
  if [ -z "$nofatal" -o "x$1" != "x" ]; then
    cleanup
    rm -f $ENV
    exit 1
  fi
}

function log_success()
{
  if [ -n "$1" ]; then echo -n "$1, "; fi
  echo "OK."
  echo -e "$1\n\n" >> $LOG
}

function log_failure()
{
  echo -e "\n  ** $1!"
  echo -e "** $1!\n" >> $LOG
}

function cnf_append()
{
  printf "%-30s := %s\n" "$1" "$2" >> $CNF
}

# Wrapper for ancient /usr/bin/which on darwin that always returns 0
function which_wrapper()
{
  if [ -z "$have_ancient_which" ]; then
    if which /bin/___cErTaINly_a_nOn_eXisTing_fIle___ 2> /dev/null > /dev/null; then
      have_ancient_which="yes"
    else
      have_ancient_which="no"
    fi
  fi
  if [ "$have_ancient_which" = "yes" ]; then
    local retval=`which $* 2>/dev/null`
    echo "$retval"
    test -n "$retval" -a -e "$retval"
  else
    which $* 2> /dev/null
  fi
}

function check_avail()
{
   if [ -z "$1" ]; then
     log_failure "$2 is empty"
     fail $3
     return 1
   elif which_wrapper $1 > /dev/null; then
     return 0
   else
     log_failure "$1 (variable $2) not found"
     fail $3
     return 1
   fi
}

# Prepare a test
function test_header()
{
  echo "***** Checking $1 *****" >> $LOG
  echo -n "Checking for $1: "
}

# Compile a test
function test_compile()
{
  echo "compiling the following source file:" >> $LOG
  cat .tmp_src.cc >> $LOG
  echo "using the following command line:" >> $LOG
  echo "$CXX -O -Wall -o .tmp_out .tmp_src.cc \"$1\"" >> $LOG
  $CXX -O -Wall -o .tmp_out .tmp_src.cc $1 >> $LOG 2>&1
  if (($?!=0)); then
    if [ -z "$4" ]; then
      echo -e "\n  $2 not found at $1 or $3 headers not found"
      echo      "  Check the file $LOG for detailed error information."
      fail
    else
      echo "not found."
      echo -e "\n" >> $LOG
    fi
    return 1
  fi
  return 0
}

# Execute a compiled test binary
function test_execute()
{
  echo "executing the binary" >> $LOG
  ./.tmp_out > .test_execute.log
  rc=$?
  cat .test_execute.log | tee -a $LOG
  if (($rc!=0)); then
    fail $1
    return 1
  fi
  echo -e "\n\n" >> $LOG
  return 0
}

#
# Check for OS, MACHINE, CPU
#
function check_environment()
{
  test_header environment
  CPU=`uname -m`
  case "$CPU" in
    i[3456789]86|x86)
      MACHINE='x86'
      ;;
    x86_64|amd64)
      MACHINE='amd64'
      CPU='k8'

      echo ""
      echo ""
      echo "Warning! Support for AMD64 host systems is work in progress."
      echo "         Don't expect it to work or even to build at the moment."
      echo ""
      echo ""
      ;;
    *)
      log_failure "Cannot determine system"
      exit 1
      ;;
  esac
  OS=`uname -s | sed -e 's/GNU\/Linux/Linux/g' | tr 'A-Z' 'a-z'`
  case "$OS" in
    linux)
      ;;
    darwin)
      ;;
    *)
      log_failure "Cannot determine OS"
      exit 1
      ;;
  esac
  DEVDIR_BIN="$DEVDIR/$OS.$MACHINE/bin"
  KBUILDDIR_BIN="$KBUILDDIR/bin/$OS.$MACHINE"
  log_success "Determined $OS.$MACHINE"

  # Automatically disable XPCOM on darwin.
  if [ "$OS" = "darwin" -a $WITH_XPCOM -eq 1 ]; then
    WITH_XPCOM=0
    WITH_LIBIDL=0
    WITH_QT=0
    echo "Disabling checks for XPCOM related components."
  fi
}

#
# Check for gcc with version >= 3.2.
# We depend on a working gcc, if we fail terminate in every case.
#
function check_gcc()
{
  test_header gcc
  if check_avail "$CC" CC really; then
    cc_ver=`$CC -dumpversion`
    if check_avail "$CXX" CXX really; then
      cxx_ver=`$CXX -dumpversion`
      cc_maj=`echo $cc_ver|cut -d. -f1`
      cc_min=`echo $cc_ver|cut -d. -f2`
      if [ "x$cc_ver" != "x$cxx_ver" ]; then
        log_failure "gcc version $cc_ver does not match g++ version $cxx_ver"
        fail really
      elif (($cc_maj>3)); then
        if [ "$MACHINE" = "x86" ]; then
          log_success "found version $cc_ver, using precompiled objects for recompiler"
          cnf_append "VBOX_USING_GCC4" "1"
        else
          log_success "found version $cc_ver"
        fi
      elif (($cc_maj<3 || $cc_min<2)); then
        log_failure "gcc version $cc_ver found, expected at least gcc version 3.2"
        fail really
      else
        log_success "found version $cc_ver"
      fi
      if [ "$CC" != "gcc" ]; then
        cnf_append "TOOL_GCC3_CC" "$CC"
        cnf_append "TOOL_GCC3_AS" "$CC"
      fi
      if [ "$CXX" != "g++" ]; then
        cnf_append "TOOL_GCC3_CXX" "$CXX"
        cnf_append "TOOL_GCC3_LD"  "$CXX"
      fi
    fi
  fi
}

#
# Check for the bcc compiler, needed for compiling the BIOS
#
function check_bcc()
{
  test_header bcc
  if check_avail "$BCC" BCC; then
    bcc_ver=`$BCC -v 2>&1|grep version|sed 's+^bcc: version \(.*\)+\1+'`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      echo "compiling the following source file:" >> $LOG
      echo '
int foo(a)
  int a;
{
  return 0;
}
' > .tmp_src.c
      cat .tmp_src.c >> $LOG
      local bcc_path=`which_wrapper $BCC`
      local bcc_dir="`dirname $bcc_path`/"
      echo "using the following command line:" >> $LOG
      echo "$BCC -B $bcc_dir -C-c -3 -S -o .tmp_out .tmp_src.c" >> $LOG
      $BCC -B $bcc_dir -C-c -3 -S -o .tmp_out .tmp_src.c >> $LOG 2>&1
      if (($?!=0)); then
        log_failure "not found"
        fail
      else
        log_success "found version $bcc_ver"
        cnf_append "VBOX_BCC" "$bcc_path -B $bcc_dir"
      fi
    fi
  fi
}

#
# Check for the as86 assembler, needed for compiling the BIOS
#
function check_as86()
{
  test_header as86
  if check_avail "$AS86" AS86; then
    as86_ver=`$AS86 -v 2>&1|grep version|sed 's+^as86 version: \(.*\)+\1+'`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found version $as86_ver"
      cnf_append "VBOX_AS86" "`which_wrapper $AS86`"
    fi
  fi
}

#
# Check for yasm, needed to compile assembler files
#
function check_yasm()
{
  test_header yasm
  if check_avail "$YASM" YASM; then
    yasm_ver=`$YASM --version|grep "^yasm"|sed 's+^yasm \(.*\)+\1+'`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      yasm_maj=`echo $yasm_ver|cut -d. -f1`
      yasm_min=`echo $yasm_ver|cut -d. -f2`
      yasm_rev=`echo $yasm_ver|cut -d. -f3`
      yasm_ver_mul=$(($yasm_maj*10000+$yasm_min*100+$yasm_rev))
      if (($yasm_ver_mul<501)); then
        log_failure "found version $yasm_ver, expected at least 0.5.1"
        fail
      else
        log_success "found version $yasm_ver"
      fi
    fi
  fi
}

#
# Check for the iasl ACPI compiler, needed to compile vbox.dsl
#
function check_iasl()
{
  test_header iasl
  if check_avail "$IASL" IASL; then
    iasl_ver=`$IASL|grep version|sed 's+^ASL.*version \([0-9]*\).*+\1+'`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found version $iasl_ver"
      cnf_append "VBOX_IASLCMD" "`which_wrapper $IASL`"
    fi
  fi
}

#
# Check for xsltproc, needed by Main
#
function check_xsltproc()
{
  test_header xslt
  if check_avail "$XSLTPROC" XSLTPROC; then
    xsltproc_ver=`$XSLTPROC --version`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found"
      cnf_append "VBOX_XSLTPROC" "`which_wrapper $XSLTPROC`"
    fi
  fi
}

#
# Check for mkisofs, needed to build the CDROM image containing the additions
#
function check_mkisofs()
{
  test_header mkisofs
  if which_wrapper $GENISOIMAGE > /dev/null; then
    mkisofs_ver=`$GENISOIMAGE --version`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found $mkisofs_ver"
      cnf_append "VBOX_MKISOFS" "`which_wrapper $GENISOIMAGE`"
    fi
  elif check_avail "$MKISOFS" MKISOFS; then
    mkisofs_ver=`$MKISOFS --version`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found $mkisofs_ver"
      cnf_append "VBOX_MKISOFS" "`which_wrapper $MKISOFS`"
    fi
  fi
}

#
# Check for xalan, needed by VBoxXML
#
function check_xalan()
{
  test_header xalan
  echo '
#include <cstdio>
#include <xalanc/Include/XalanVersion.hpp>
extern "C" int main(void)
{
  printf("found version %d.%d.%d",
         XALAN_VERSION_MAJOR, XALAN_VERSION_MINOR, XALAN_VERSION_REVISION);
#if _XALAN_VERSION >= 10800
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 1.8.0 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "$LIBXALAN ${INCXALAN:+-I$INCXALAN}" xalan xalanc; then
    if test_execute; then
      cnf_append "SDK_VBOX_XALAN_LIBS" `echo $LIBXALAN|sed 's+-l++'`
      cnf_append "SDK_VBOX_XALAN_INCS" "$INCXALAN"
    fi
  fi
}

#
# Check for xerces, needed by VBoxXML
#
function check_xerces()
{
  test_header xerces
  echo '
#include <cstdio>
#include <xercesc/util/XercesVersion.hpp>
extern "C" int main(void)
{
  printf("found version %d.%d.%d",
         XERCES_VERSION_MAJOR, XERCES_VERSION_MINOR, XERCES_VERSION_REVISION);
#if _XERCES_VERSION >= 20500
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 2.5.0 or higher");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "$LIBXERCES ${INCXERCES:+-I$INCXERCES}" xerces xercesc; then
    if test_execute; then
      cnf_append "SDK_VBOX_XERCES_LIBS" `echo $LIBXERCES|sed 's+-l++'`
      cnf_append "SDK_VBOX_XERCES_INCS" "$INCXERCES"
    fi
  fi
}

#
# Check for libIDL, needed by xpcom
#
check_libidl()
{
  test_header libIDL

  if which_wrapper libIDL-config-2 > /dev/null; then
    libidl_ver=`libIDL-config-2 --version`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found version $libidl_ver"
      cnf_append "VBOX_LIBIDL_CONFIG" \
        "PKG_CONFIG_PATH=`libIDL-config-2 --prefix`/lib/pkgconfig `which_wrapper libIDL-config-2`"
    fi
  elif check_avail "libIDL-config" libIDL-config; then
    libidl_ver=`libIDL-config --version`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found version $libidl_ver"
      cnf_append "VBOX_LIBIDL_CONFIG" `which_wrapper libIDL-config`
    fi
  fi
}

#
# Check for openssl, needed for RDP
#
function check_ssl()
{
  test_header ssl
  echo '
#include <cstdio>
#include <openssl/opensslv.h>
extern "C" int main(void)
{
  printf("found version %s", OPENSSL_VERSION_TEXT);
#if OPENSSL_VERSION_NUMBER >= 0x0090700
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 0.9.7 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile $LIBCRYPTO libcrypto openssl; then
    if test_execute nofatal; then
      cnf_append "SDK_VBOX_OPENSSL_INCS" ""
      cnf_append "SDK_VBOX_OPENSSL_LIBS" `echo $LIBCRYPTO|sed 's+-l++'`
    fi
  fi
}

#
# Check for pthread, needed by VBoxSVC, frontends, ...
#
function check_pthread()
{
  test_header pthread
  echo '
#include <cstdio>
#include <pthread.h>
extern "C" int main(void)
{
  pthread_mutex_t mutex;
  if (pthread_mutex_init(&mutex, NULL)) {
    printf("pthread_mutex_init() failed\n");
    return 1;
  }
  if (pthread_mutex_lock(&mutex)) {
    printf("pthread_mutex_lock() failed\n");
    return 1;
  }
  if (pthread_mutex_unlock(&mutex)) {
    printf("pthread_mutex_unlock() failed\n");
    return 1;
  }
  printf("found, OK.\n");
}
' > .tmp_src.cc
  if test_compile $LIBPTHREAD pthread pthread; then
    if test_execute; then
      cnf_append "LIB_PTHREAD" `echo $LIBPTHREAD|sed 's+-l++'`
    fi
  fi
}

#
# Check for zlib, needed by VBoxSVC, Runtime, ...
#
function check_z()
{
  test_header zlib
  echo '
#include <cstdio>
#include <zlib.h>
extern "C" int main(void)
{
  printf("found version %s", ZLIB_VERSION);
#if ZLIB_VERNUM >= 0x1210
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 1.2.1 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "$LIBZ ${INCZ:+-I$INCZ}" zlib zlib; then
    if test_execute; then
      cnf_append "SDK_VBOX_ZLIB_LIBS" `echo $LIBZ|sed 's+-l++'`
      cnf_append "SDK_VBOX_ZLIB_INCS" "$INCZ"
    fi
  fi
}

#
# Check for libpng, needed by kchmviewer
#
function check_png()
{
  test_header libpng
  echo '
#include <cstdio>
#include <png.h>
extern "C" int main(void)
{
  printf("found version %s", PNG_LIBPNG_VER_STRING);
#if PNG_LIBPNG_VER >= 10205
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 1.2.5 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "$LIBPNG ${INCPNG:+-I$INCPNG}" libpng libpng nofatal; then
    if test_execute nofatal; then
      cnf_append "SDK_VBOX_LIBPNG_LIBS" `echo $LIBPNG|sed 's+-l++'`
      cnf_append "SDK_VBOX_LIBPNG_INCS" "$INCPNG"
    fi
  fi
}

#
# Check for pam, needed by VRDPAuth
# Version 79 was introduced in 9/2005, do we support older versions?
# Debian/sarge uses 76
# OpenSUSE comes with 0.99.xxx where they changed the versioning scheme.
#
function check_pam()
{
  test_header pam
  echo '
#include <cstdio>
#include <security/pam_appl.h>
extern "C" int main(void)
{
  printf("found version %d", __LIBPAM_VERSION);
  if (__LIBPAM_VERSION >= 76)
  {
    printf(", OK.\n");
    return 0;
  }
  else
  {
    printf(", expected version 76 or higher\n");
    return 1;
  }
}
' > .tmp_src.cc
  if test_compile "-lpam" pam pam nofatal; then
    if test_execute nofatal; then
      return 0;
    fi
  fi
  test_header linux_pam
  echo '
#include <cstdio>
#include <security/pam_appl.h>
extern "C" int main(void)
{
  printf("found version %d.%d", __LINUX_PAM__, __LINUX_PAM_MINOR__);
  if (__LINUX_PAM__ >= 1)
  {
    printf(", OK.\n");
    return 0;
  }
  else
  {
    printf(", expected version 1.0 or higher\n");
    return 1;
  }
}
' > .tmp_src.cc
  if test_compile "-lpam" pam pam; then
    test_execute
  fi
}

#
# Check for the SDL library, needed by VBoxSDL and VirtualBox
# We depend at least on version 1.2.7
#
function check_sdl()
{
  test_header SDL
  echo '
#include <cstdio>
#include <SDL/SDL.h>
#include <SDL/SDL_main.h>
extern "C" int main(void)
{
  printf("found version %d.%d.%d",
         SDL_MAJOR_VERSION, SDL_MINOR_VERSION, SDL_PATCHLEVEL);
#if SDL_VERSION_ATLEAST(1,2,7)
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 1.2.7 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "$LIBSDL $LIBSDLMAIN ${INCSDL:+-I$INCSDL}" SDL SDL; then
    if test_execute; then
      cnf_append "LIB_SDK_LIBSDL_SDL" `echo $LIBSDL|sed 's+-l++'`
      cnf_append "LIB_SDK_LIBSDL_SDLMAIN" `echo $LIBSDLMAIN|sed 's+-l++'`
      [ -n "$INCSDL" ] && cnf_append "SDK_LIBSDL_INCS" "$INCSDL"
    fi
  fi
}

#
# Check for the SDL_ttf library, needed by VBoxSDL (secure label)
#
function check_sdl_ttf()
{
  test_header SDL_ttf
  echo '
#include <cstdio>
#include <SDL/SDL_ttf.h>
#ifndef SDL_TTF_MAJOR_VERSION
#define SDL_TTF_MAJOR_VERSION TTF_MAJOR_VERSION
#define SDL_TTF_MINOR_VERSION TTF_MINOR_VERSION
#define SDL_TTF_PATCHLEVEL    TTF_PATCHLEVEL
#endif
extern "C" int main(void)
{
  printf("found version %d.%d.%d",
         SDL_TTF_MAJOR_VERSION, SDL_TTF_MINOR_VERSION, SDL_TTF_PATCHLEVEL);
#if 10000*SDL_TTF_MAJOR_VERSION + 100*SDL_TTF_MINOR_VERSION + SDL_TTF_PATCHLEVEL >= 20006
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 2.0.6 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "-lSDL_ttf" SDL_ttf SDL_ttf; then
    test_execute
  fi
}

#
# Check for libasound, needed by the ALSA audio backend
#
function check_alsa()
{
  test_header ALSA
  echo '
#include <alsa/asoundlib.h>
extern "C" int main(void)
{
  printf("found version %d.%d.%d",
         SND_LIB_MAJOR, SND_LIB_MINOR, SND_LIB_SUBMINOR);
#if 10000*SND_LIB_MAJOR + 100*SND_LIB_MINOR + SND_LIB_SUBMINOR >= 10006
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 1.0.6 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  if test_compile "-lasound" asound asound; then
    test_execute
  fi
}

#
# Check for the Xcursor library, needed by VBoxSDL and VBoxBFE
#
function check_xcursor()
{
  test_header Xcursor
  echo '
#include <cstdio>
#include <X11/Xlib.h>
#include <X11/Xcursor/Xcursor.h>
extern "C" int main(void)
{
  XcursorImage *cursor = XcursorImageCreate (10, 10);
  XcursorImageDestroy(cursor);
  return 0;
}
' > .tmp_src.cc
  if test_compile "$LIBX11 $LIBXCURSOR" Xcursor Xcursor; then
    log_success "found"
    cnf_append "LIB_XCURSOR" `echo $LIBXCURSOR|sed 's+-l++'`
  fi
}

#
# Check for the X libraries (Xext, X11)
#
function check_x()
{
  test_header "X libraries"
  echo '
#include <cstdio>
#include <X11/Xlib.h>
extern "C" int main(void)
{
  Display *dpy;
  int scrn_num;
  Screen *scrn;
  Window win;

  dpy      = XOpenDisplay(NULL);
  scrn_num = DefaultScreen(dpy);
  scrn     = ScreenOfDisplay(dpy, scrn_num);
  win      = XCreateWindow(dpy, RootWindowOfScreen(scrn), 0, 0, 100, 100,
                           0, 16, InputOutput, CopyFromParent, 0, NULL);
  XDestroyWindow(dpy, win);
}
' > .tmp_src.cc
  if test_compile "$LIBX11" Xlibs Xlibs; then
    log_success "found"
  fi
}

#
# Check for the QT library, needed by VirtualBox
#
function check_qt()
{
  test_header Qt
  echo '
#include <cstdio>
#include <qglobal.h>
extern "C" int main(void)
{
  printf("found version %s", QT_VERSION_STR);
#if QT_VERSION >= 0x030305
  printf(", OK.\n");
  return 0;
#elif QT_VERSION >= 0x030300
  printf("\n  ** WARNING: QT < 3.3.5 has known problems!\n");
#else
  printf(", expected version 3.3.0 or higher\n");
  return 1;
#endif
}
' > .tmp_src.cc
  found_qt=0
  for q in $QTDIR; do
    echo "compiling the following source file:" >> $LOG
    cat .tmp_src.cc >> $LOG
    echo "using the following command line:" >> $LOG
    echo "$CXX -O -Wall -o .tmp_out .tmp_src.cc -I$q/include -L$q/lib -lqt-mt" >> $LOG
    $CXX -O -Wall -o .tmp_out .tmp_src.cc -I$q/include -L$q/lib -lqt-mt >> $LOG 2>&1
    if (($?==0)); then
      if test_execute; then
        cnf_append "QTDIR" `cd $q ; pwd`
        found_qt=1
        break
      fi
    fi
  done
  if (($found_qt!=1)); then
    echo -e "\n  Qt not found at \"$QTDIR\" or Qt headers not found"
    echo      "  Check the file $LOG for detailed error information."
    fail
    return 1
  fi
  test_header "Qt devtools"
  if check_avail "$q/bin/moc" QTDIR/bin; then
    moc_ver=`$q/bin/moc 2>&1 -v|sed 's+^.*(Qt \(.*\))+\1+'`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found version $moc_ver"
    fi
  fi
}

#
# Check for Linux sources
#
function check_linux()
{
  test_header "Linux kernel sources"
  echo '
#include <linux/version.h>
int printf(const char *format, ...);
int main(void)
{
  printf("found version %d.%d.%d",  LINUX_VERSION_CODE / 65536,
                                   (LINUX_VERSION_CODE % 65536) / 256,
                                    LINUX_VERSION_CODE          % 256);
#if LINUX_VERSION_CODE > KERNEL_VERSION(2,4,0)
  printf(", OK.\n");
  return 0;
#else
  printf(", expected version 2.4.0 or higher\n");
  return 1;
#endif
}
' > .tmp_src.c
  echo "compiling the following source file:" >> $LOG
  cat .tmp_src.c >> $LOG
  echo "using the following command line:" >> $LOG
  echo "$CC -O -Wall -o .tmp_out .tmp_src.c -nostdinc -I$LINUX/include" >> $LOG
  $CC -O -Wall -o .tmp_out .tmp_src.c -nostdinc -I$LINUX/include >> $LOG 2>&1
  if (($?!=0)); then
    echo -e "\n  Linux kernel headers not found at $LINUX"
    echo      "  Check the file $LOG for detailed error information."
    fail
  else
    if test_execute; then
      cnf_append "VBOX_LINUX_SRC" `cd $LINUX ; pwd`
    fi
  fi
}

#
# Check for kchmviewer, needed to display the online help
#
function check_kchmviewer()
{
  test_header kchmviewer
  if check_avail "$KCHMVIEWER" KCHMVIEWER; then
    kchmviewer_ver=`$KCHMVIEWER --version|grep "^KchmViewer:"|sed 's+^KchmViewer: \(.*\)+\1+'`
    if (($?!=0)); then
      log_failure "not found"
      fail
    else
      log_success "found version $kchmviewer_ver"
    fi
  fi
}

#
# Check for the kBuild tools, we don't support GNU make
#
function check_kbuild()
{
  test_header kBuild
  if check_avail "$KBUILDDIR_BIN/kmk" KBUILDDIR really; then
    log_success "found"
    echo "export BUILD_PLATFORM=\"$OS\"" >> $ENV
    echo "export BUILD_PLATFORM_ARCH=\"$MACHINE\"" >> $ENV
    echo "export BUILD_TARGET=\"$OS\"" >> $ENV
    echo "export BUILD_TARGET_ARCH=\"$MACHINE\"" >> $ENV
    echo "export BUILD_TARGET_CPU=\"$CPU\"" >> $ENV
    echo "export BUILD_TYPE=\"$BUILD_TYPE\"" >> $ENV
    echo "export PATH_KBUILD=\"`cd $KBUILDDIR ; pwd`\"" >> $ENV
    echo "export PATH_DEVTOOLS=\"$DEVDIR\"" >> $ENV
    echo "path_kbuild_bin=\"\$PATH_KBUILD/bin/\$BUILD_TARGET.\$BUILD_PLATFORM_ARCH\"" >> $ENV
    echo "path_dev_bin=\"\$PATH_DEVTOOLS/\$BUILD_TARGET.\$BUILD_PLATFORM_ARCH\"/bin" >> $ENV
    echo "echo \"\$PATH\" | grep -q \"\$path_kbuild_bin\" || PATH=\"\$path_kbuild_bin:\$PATH\"" >> $ENV
    echo "echo \"\$PATH\" | grep -q \"\$path_dev_bin\" || PATH=\"\$path_dev_bin:\$PATH\"" >> $ENV
    echo "export PATH" >> $ENV
    echo "unset path_kbuild_bin path_dev_bin" >> $ENV
  fi
}


#
# Check for compiler.h
# Some Linux distributions include "compiler.h" in their libc linux 
# headers package, some don't.  Most don't need it, building might (!) 
# not succeed on openSUSE without it.
#
# See http://www.mail-archive.com/qemu-devel%40nongnu.org/msg07980.html
#
function check_compiler_h
{
  test_header compiler.h
  if ! test -f "/usr/include/linux/compiler.h"; then
    cnf_append "VBOX_WITHOUT_LINUX_COMPILER_H" "1"
    log_success "compiler.h not found"
  else
    log_success "compiler.h found"
  fi
}


#
# Show help
#
function show_help()
{
  cat << EOF
Usage: ./configure [OPTIONS]...

Configuration:
  -h, --help              display this help and exit
  --nofatal               don't abort on errors
  --disable-xpcom         disable XPCOM and related stuff
  --disable-sdl-ttf       disable SDL_ttf detection

Paths:
  --with-gcc=PATH         position of the gcc compiler [$CC]
  --with-g++=PATH         position of the g++ compiler [$CXX]
  --with-kbuild=DIR       kbuild directory [$KBUILDDIR]
  --with-iasl=PATH        the position of the iasl compiler [$IASL]
  --with-linux=DIR        Linux kernel source directory [$LINUX]
  --with-mkisofs=PATH     position of mkisofs [$MKISOFS]
  --with-qt-dir=DIR       directory for QT headers/libraries [$QTDIR]
  --with-xalan=LIB        position of the xalan library [$LIBXALAN]
  --with-xerces=LIB       position of the xerces library [$LIBXERCES]

Build type:
  -d, --build-debug       build with debugging symbols and assertions
EOF
  exit 0
}


#
# The body.
#

# scan command line options
for option; do
  case "$option" in
    --help|-help|-h)
      show_help
      ;;
    --nofatal)
      nofatal=1
      ;;
    --with-gcc=*)
      CC=`echo $option | cut -d'=' -f2`
      ;;
    --with-g++=*)
      CXX=`echo $option | cut -d'=' -f2`
      ;;
    --with-kbuild=*)
      KBUILDDIR=`echo $option | cut -d'=' -f2`
      if echo $KBUILDDIR|grep -q "$INVALID_CHARS"; then
        echo "Error: KBUILDDIR contains invalid characters!"
        exit 1
      fi
      ;;
    --with-qt-dir=*)
      QTDIR=`echo $option | cut -d'=' -f2`
      ;;
    --with-iasl=*)
      IASL=`echo $option | cut -d'=' -f2`
      ;;
    --with-linux=*)
      LINUX=`echo $option | cut -d'=' -f2`
      ;;
    --with-mkisofs=*)
      MKISOFS=`echo $option | cut -d'=' -f2`
      ;;
    --with-xalan=*)
      LIBXALAN=`echo $option | cut -d'=' -f2`
      ;;
    --with-xerces=*)
      LIBXERCES=`echo $option | cut -d'=' -f2`
      ;;
    --disable-xpcom)
      WITH_XPCOM=0
      ;;
    --disable-sdl-ttf)
      WITH_SDL_TTF=0
      ;;
    --disable-qt)
      WITH_QT=0
      ;;
    --build-debug|-d)
      BUILD_TYPE=debug
      ;;
    --ose)
      OSE=2
      ;;
    --odir=*)
      ODIR=`echo $option | cut -d'=' -f2`
      ;;
    *)
      echo
      echo "Unrecognized option \"$option\""
      echo
      show_help
      ;;
  esac
done

LOG="${ODIR:+$ODIR/}$LOG"
ENV="${ODIR:+$ODIR/}$ENV"
CNF="${ODIR:+$ODIR/}$CNF"

# initialize output files
cat > $LOG << EOF
# Log file generated by
#
#   '$0 $*'
#

EOF
cat > $CNF << EOF
# -*- Makefile -*-
#
# automatically generated by
#
#   '$0 $*'
#
# It will be completely overwritten if configure is executed again.
#

EOF
cat > $ENV << EOF
#!/bin/bash
#
# automatically generated by
#
#   '$0 $*'
#
# It will be completely overwritten if configure is executed again.
# Make sure you source this file once before you start to build VBox.
#

EOF

# test if we are OSE
if (($OSE==1)) && [ -d "`cd $(dirname $0); pwd`/src/VBox/Devices/USB" ]; then
  echo "Found USB devices, assuming VBOX_OSE = FALSE" >> $LOG
  echo >> $LOG
  OSE=0
fi

# first determine our environment
check_environment
check_kbuild

# some things are not available in for OSE
if (($OSE)); then
  cnf_append "VBOX_OSE" "1"
  cnf_append "VBOX_WITH_TESTSUITE" ""
  cnf_append "VBOX_WITH_WIN32_ADDITIONS" ""

  if [ "$OS" = "linux" ]; then
    cnf_append "VBOX_WITH_LINUX_ADDITIONS" "1"
  else
    cnf_append "VBOX_WITH_LINUX_ADDITIONS" ""
  fi
  echo >> $CNF
fi

# emit disable directives corresponding to any --disable-xxx options.
(($WITH_XPCOM==0)) && cnf_append "VBOX_WITH_MAIN" ""
(($WITH_QT==0)) && cnf_append "VBOX_WITH_QTGUI" ""
(($WITH_SDL_TTF==0)) && cnf_append "VBOX_WITH_SECURELABEL" ""

# append the tools directory to the default search path
echo "$PATH" | grep -q "$DEVDIR_BIN" || PATH="$PATH:$DEVDIR_BIN"

# append some extra paths
PATH="$PATH:/opt/gnome/bin"

# the tools
check_gcc
[ "$OS" != "darwin" ] && check_as86
[ "$OS" != "darwin" ] && check_bcc
[ "$OS" != "darwin" ] && check_iasl
# don't check for yasm for the time beeing as 0.40 and 0.50 both have known bugs
# [ "$OS" != "darwin" ] && check_yasm
[ "$OS" != "darwin" ] && check_xsltproc
(($OSE==0)) && check_mkisofs

# the libraries
(($WITH_XPCOM==1)) && check_xalan
(($WITH_XPCOM==1)) && check_xerces
(($WITH_LIBIDL==1)) && check_libidl
(($OSE==0)) && check_ssl
[ "$OS" != "darwin" ] && check_pthread
[ "$OS" != "darwin" ] && check_z
(($OSE==0)) && check_png
(($OSE==0)) && [ "$OS" = "linux" ] && check_pam
[ "$OS" != "darwin" ] && check_sdl
(($WITH_SDL_TTF==1)) && (($OSE==0)) && check_sdl_ttf
[ "$OS" != "darwin" ] && check_alsa
[ "$OS" != "darwin" ] && check_x
[ "$OS" != "darwin" ] && check_xcursor
(($WITH_QT==1)) && check_qt

# Linux-specific
[ "$OS" = "linux" ] && check_linux
[ "$OS" = "linux" ] && check_compiler_h

# success!
echo
echo "Successfully generated '$CNF' and '$ENV'."
echo "Source '$ENV' once before you start to build VBox:"
echo ""
echo "  source $ENV"
echo "  kmk"
echo ""
if [ "$OS" = "linux" ]; then
    echo "To compile the kernel module, do:"
    echo ""
    echo "  cd ./out/$OS.$MACHINE/$BUILD_TYPE/bin/src"
    echo "  make"
    echo ""
fi
echo "Enjoy!"
cleanup