configure

#!/bin/sh
set -e

Command="$0 $*"
CommandDirname=`dirname $0`
SourceDir=$(cd $CommandDirname && pwd)
# Appends a CMake cache entry definition to the CMakeCacheEntries variable.
#   $1: variable name
#   $2: CMake type
#   $3: value
append_cache_entry() {
  case "$3" in
    *\ * )
      # string contains whitespace
      CMakeCacheEntries="$CMakeCacheEntries -D \"$1:$2=$3\""
      ;;
    *)
      # string contains no whitespace
      CMakeCacheEntries="$CMakeCacheEntries -D $1:$2=$3"
      ;;
  esac
}

# Appends a BOOL cache entry to the CMakeCacheEntries variable.
#   $1: flag name
#   $2: value (ON or OFF)
set_build_flag() {
  FlagName=''
  case "$1" in
    testing)                 FlagName='LIB_NET_ENABLE_TESTS' ;;
    *)
      echo "Invalid flag '$1'.  Try $0 --help to see available options."
      exit 1
      ;;
  esac
  append_cache_entry $FlagName BOOL $2
}

set_log_level() {
  case "$1" in
    trace)                   level='4' ;;
    debug)                   level='3' ;;
    warning)                 level='2' ;;
    error)                   level='1' ;;
    none)                   level='0' ;;
    *)
      echo "Invalid log level '$1'.  Try $0 --help to see available options."
      exit 1
      ;;
  esac

  append_cache_entry 'LIB_NET_LOG_LEVEL' STRING $level
}

# Set defaults.
CMakeBuildDir=""
CMakeCacheEntries=""

# Parse user input.
while [ $# -ne 0 ]; do
  # Fetch the option argument.
  case "$1" in
    --*=*) optarg=`echo "$1" | sed 's/[-_a-zA-Z0-9]*=//'` ;;
    --enable-*) optarg=`echo "$1" | sed 's/--enable-//'` ;;
    --disable-*) optarg=`echo "$1" | sed 's/--disable-//'` ;;
    *) ;;
  esac
  # Consume current input.
  case "$1" in
    --build-type=*)
      append_cache_entry CMAKE_BUILD_TYPE STRING "$optarg"
      ;;
    --enable-*)
      set_build_flag $optarg ON
      ;;
    --disable-*)
      set_build_flag $optarg OFF
      ;;
    --openssl-root-dir=*)
      append_cache_entry OPENSSL_ROOT_DIR PATH "$optarg"
      ;;
    --compiler=*)
      append_cache_entry CMAKE_CXX_COMPILER STRING "$optarg"
      ;;
    --log-level=*)
      set_log_level "$optarg"
      ;;
    *)
      echo "Invalid option '$1'. Try $0 --help to see available options."
      exit 1
      ;;
  esac
  # Get next input.
  shift
done

if [ -z "$CMakeBuildDir" ]; then
  CMakeBuildDir="$SourceDir/build"
fi

# Check for `cmake` command.
if [ -z "$CMakeCommand" ]; then
  # Prefer cmake3 over "regular" cmake (cmake == cmake2 on RHEL).
  if command -v cmake3 >/dev/null 2>&1 ; then
    CMakeCommand="cmake3"
  elif command -v cmake >/dev/null 2>&1 ; then
    CMakeCommand="cmake"
  else
    echo "This package requires CMake, please install it first."
    echo "Then you may use this script to configure the CMake build."
    echo "Note: pass --cmake=PATH to use cmake in non-standard locations."
    exit 1
  fi
fi

# Make sure the build directory is an absolute path.
case "$CMakeBuildDir" in
  /*)
    CMakeAbsoluteBuildDir="$CMakeBuildDir"
    ;;
  *)
    CMakeAbsoluteBuildDir="$SourceDir/$CMakeBuildDir"
    ;;
esac

# If a build directory exists, delete any existing cache to have a clean build.
if [ -d "$CMakeAbsoluteBuildDir" ]; then
  if [ -f "$CMakeAbsoluteBuildDir/CMakeCache.txt" ]; then
    rm -f "$CMakeAbsoluteBuildDir/CMakeCache.txt"
  fi
else
  mkdir -p "$CMakeAbsoluteBuildDir"
fi

# Run CMake.
cd "$CMakeAbsoluteBuildDir"
if [ -n "$CMakeGenerator" ]; then
  "$CMakeCommand" -G "$CMakeGenerator" $CMakeCacheEntries "$SourceDir"
else
  "$CMakeCommand" $CMakeCacheEntries "$SourceDir"
fi

# Generate a config.status file that allows re-running a clean build.
printf "#!/bin/sh\n\n" > config.status
printf "# Switch to the source of this build directory.\n" >> config.status
printf "cd \"%s\"\n\n" "$SourceDir" >> config.status
printf "# Invoke the command to configure this build.\n" >> config.status
if [ -n "$CXX" ]; then
  printf "CXX=\"%s\"\n" "$CXX" >> config.status
fi
if [ -n "$CXXFLAGS" ]; then
  printf "CXXFLAGS=\"%s\"\n" "$CXXFLAGS" >> config.status
fi
if [ -n "$LDFLAGS" ]; then
  printf "LDFLAGS=\"%s\"\n" "$LDFLAGS" >> config.status
fi
echo $Command >> config.status
chmod u+x config.status