cmake functions

# SPDX-License-Identifier: Unlicense

# include( CMakePrintHelpers REQUIRED )

# *INDENT-OFF*

# `abort_if_in_source` prints a fatal error message to stderr and exits the
# make if attempting to build in the source directory.
function( abort_if_in_source_build )
  # Require out-of-source builds
  file( TO_CMAKE_PATH "${PROJECT_BINARY_DIR}/CMakeLists.txt" LOC_PATH )
  if( EXISTS "${LOC_PATH}" )
    message( FATAL_ERROR
      "You cannot build in a source directory (or any directory with a CMakeLists.txt file). Please make a build subdirectory. Feel free to remove CMakeCache.txt and CMakeFiles." )
  endif()
endfunction()

# `print_all_variables` prints all the currently defined variables and their
# values. The variables are printed in alphabetical order.
function( print_all_variables )
  get_cmake_property( _vars VARIABLES )
  list( SORT _vars )

  foreach( _varName ${_vars} )
    message( STATUS "${_varName}=${${_varName}}" )
  endforeach()
endfunction()