From 02e8f2956014bd17c4e5a68757776fffc6d43c51 Mon Sep 17 00:00:00 2001
From: Andrew Kaster <akaster@serenityos.org>
Date: Mon, 4 Jul 2022 11:01:05 -0600
Subject: [PATCH] Meta: Use CMAKE_INSTALL_FOODIR variables instead of
 hardcoding usr/foo

In preparation for future refactoring of Lagom, let's use the variables
from GNUInstallDirs as much as possible for the helper macros and other
scripts used by the main build already.
---
 CMakeLists.txt                   | 12 +++++++-----
 Meta/CMake/code_generators.cmake |  2 +-
 Meta/CMake/utils.cmake           |  8 ++++----
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 96ebfbff9d..7a0f794319 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -152,13 +152,15 @@ if (ENABLE_ALL_THE_DEBUG_MACROS)
     include(all_the_debug_macros)
 endif(ENABLE_ALL_THE_DEBUG_MACROS)
 
+set(CMAKE_STAGING_PREFIX "${CMAKE_BINARY_DIR}/Root")
+set(CMAKE_INSTALL_PREFIX "${CMAKE_BINARY_DIR}/Root")
+set(CMAKE_INSTALL_DATAROOTDIR res)
+set(CMAKE_INSTALL_INCLUDEDIR usr/include)
+set(CMAKE_INSTALL_LIBDIR usr/lib)
+
 configure_file(AK/Debug.h.in AK/Debug.h @ONLY)
 configure_file(Kernel/Debug.h.in Kernel/Debug.h @ONLY)
-install(FILES ${CMAKE_CURRENT_BINARY_DIR}/AK/Debug.h DESTINATION usr/include/AK)
-
-set(CMAKE_STAGING_PREFIX ${CMAKE_BINARY_DIR}/Root)
-set(CMAKE_INSTALL_PREFIX ${CMAKE_BINARY_DIR}/Root)
-set(CMAKE_INSTALL_DATAROOTDIR ${CMAKE_BINARY_DIR}/Root/res)
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/AK/Debug.h" DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/AK")
 
 # We disable it completely because it makes cmake very spammy.
 # This will need to be revisited when the Loader supports RPATH/RUN_PATH.
diff --git a/Meta/CMake/code_generators.cmake b/Meta/CMake/code_generators.cmake
index 20c7ddccfa..e54a4c1023 100644
--- a/Meta/CMake/code_generators.cmake
+++ b/Meta/CMake/code_generators.cmake
@@ -37,7 +37,7 @@ function(compile_ipc source output)
     #       https://cmake.org/cmake/help/v3.23/command/cmake_path.html#relative-path
     string(LENGTH ${SerenityOS_SOURCE_DIR} root_source_dir_length)
     string(SUBSTRING ${CMAKE_CURRENT_SOURCE_DIR} ${root_source_dir_length} -1 current_source_dir_relative)
-    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${output} DESTINATION usr/include${current_source_dir_relative} OPTIONAL)
+    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${output} DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/${current_source_dir_relative}" OPTIONAL)
 endfunction()
 
 function(generate_state_machine source header)
diff --git a/Meta/CMake/utils.cmake b/Meta/CMake/utils.cmake
index 1bfc3b8ea2..5da86a1d3a 100644
--- a/Meta/CMake/utils.cmake
+++ b/Meta/CMake/utils.cmake
@@ -6,7 +6,7 @@ function(serenity_install_headers target_name)
     file(GLOB_RECURSE headers RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} "*.h")
     foreach(header ${headers})
         get_filename_component(subdirectory ${header} DIRECTORY)
-        install(FILES ${header} DESTINATION usr/include/${target_name}/${subdirectory} OPTIONAL)
+        install(FILES ${header} DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/${target_name}/${subdirectory}" OPTIONAL)
     endforeach()
 endfunction()
 
@@ -39,7 +39,7 @@ function(serenity_lib target_name fs_name)
     add_library(${target_name} SHARED ${SOURCES} ${GENERATED_SOURCES})
     set_target_properties(${target_name} PROPERTIES EXCLUDE_FROM_ALL TRUE)
     set_target_properties(${target_name} PROPERTIES VERSION "serenity")
-    install(TARGETS ${target_name} DESTINATION usr/lib OPTIONAL)
+    install(TARGETS ${target_name} DESTINATION ${CMAKE_INSTALL_LIBDIR} OPTIONAL)
     set_target_properties(${target_name} PROPERTIES OUTPUT_NAME ${fs_name})
     serenity_generated_sources(${target_name})
 endfunction()
@@ -50,7 +50,7 @@ function(serenity_lib_static target_name fs_name)
     add_library(${target_name} STATIC ${SOURCES} ${GENERATED_SOURCES})
     set_target_properties(${target_name} PROPERTIES EXCLUDE_FROM_ALL TRUE)
     set_target_properties(${target_name} PROPERTIES VERSION "serenity")
-    install(TARGETS ${target_name} DESTINATION usr/lib OPTIONAL)
+    install(TARGETS ${target_name} DESTINATION ${CMAKE_INSTALL_LIBDIR} OPTIONAL)
     set_target_properties(${target_name} PROPERTIES OUTPUT_NAME ${fs_name})
     serenity_generated_sources(${target_name})
 endfunction()
@@ -60,7 +60,7 @@ function(serenity_libc target_name fs_name)
     serenity_install_sources()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -nostdlib -fpic")
     add_library(${target_name} SHARED ${SOURCES})
-    install(TARGETS ${target_name} DESTINATION usr/lib)
+    install(TARGETS ${target_name} DESTINATION ${CMAKE_INSTALL_LIBDIR})
     set_target_properties(${target_name} PROPERTIES OUTPUT_NAME ${fs_name})
     # Avoid creating a dependency cycle between system libraries and the C++ standard library. This is necessary
     # to ensure that initialization functions will be called in the right order (libc++ must come after LibPthread).