[lldb] Move create_relative_symlink function up in CMake hierarchy

[dim]

Summary

Configuring lldb with LLDB_ENABLE_PYTHON=OFF and LLDB_ENABLE_LUA=ON results in a CMake error:

CMake Error at lldb/bindings/lua/CMakeLists.txt:47 (create_relative_symlink):
  Unknown CMake command "create_relative_symlink".
Call Stack (most recent call first):
  lldb/CMakeLists.txt:117 (finish_swig_lua)

This is because the CMake function create_relative_symlink only exists in lldb/bindings/python/CMakeLists.txt, and not in lldb/bindings/lua/CMakeLists.txt.

Move the function to lldb/bindings/CMakeLists.txt, so it is available for all language bindings.

lldb/bindings/CMakeLists.txt

set(SWIG_COMMON_FLAGS
   -features autodoc
   -I${LLDB_SOURCE_DIR}/include
   -I${CMAKE_CURRENT_SOURCE_DIR}
   -D__STDC_LIMIT_MACROS
   -D__STDC_CONSTANT_MACROS
   ${DARWIN_EXTRAS}
 )
 
+function(create_relative_symlink swig_target dest_file output_dir output_name)
+  get_filename_component(dest_file ${dest_file} ABSOLUTE)
+  get_filename_component(output_dir ${output_dir} ABSOLUTE)
+  file(RELATIVE_PATH rel_dest_file ${output_dir} ${dest_file})
+  if(CMAKE_HOST_UNIX)
+    set(LLVM_LINK_OR_COPY create_symlink)
+  else()
+    set(LLVM_LINK_OR_COPY copy)
+  endif()
+  add_custom_command(TARGET ${swig_target} POST_BUILD VERBATIM
+    COMMAND ${CMAKE_COMMAND} -E ${LLVM_LINK_OR_COPY} ${rel_dest_file} ${output_name}
+    WORKING_DIRECTORY ${output_dir})
+endfunction()
+
 if (LLDB_ENABLE_PYTHON)
   add_subdirectory(python)
 endif()
 
 if (LLDB_ENABLE_LUA)
   add_subdirectory(lua)
 endif()

lldb/bindings/python/CMakeLists.txt

function(create_python_package swig_target working_dir pkg_dir)
   endif()
   add_custom_command(TARGET ${swig_target} POST_BUILD VERBATIM
     COMMAND ${CMAKE_COMMAND} -E make_directory ${pkg_dir}
     ${copy_cmd}
     ${init_cmd}
     WORKING_DIRECTORY ${working_dir})
 endfunction()
 
-function(create_relative_symlink swig_target dest_file output_dir output_name)
-  get_filename_component(dest_file ${dest_file} ABSOLUTE)
-  get_filename_component(output_dir ${output_dir} ABSOLUTE)
-  file(RELATIVE_PATH rel_dest_file ${output_dir} ${dest_file})
-  if(CMAKE_HOST_UNIX)
-    set(LLVM_LINK_OR_COPY create_symlink)
-  else()
-    set(LLVM_LINK_OR_COPY copy)
-  endif()
-  add_custom_command(TARGET ${swig_target} POST_BUILD VERBATIM
-    COMMAND ${CMAKE_COMMAND} -E ${LLVM_LINK_OR_COPY} ${rel_dest_file} ${output_name}
-    WORKING_DIRECTORY ${output_dir})
-endfunction()
-
 function(finish_swig_python swig_target lldb_python_bindings_dir lldb_python_target_dir)
   # Add a Post-Build Event to copy over Python files and create the symlink to
   # liblldb.so for the Python API(hardlink on Windows).
   add_custom_target(${swig_target} ALL VERBATIM
     COMMAND ${CMAKE_COMMAND} -E make_directory ${lldb_python_target_dir}
     DEPENDS ${lldb_python_bindings_dir}/lldb.py
     COMMENT "Python script sym-linking LLDB Python API")