From c389fbdaff34e35b0cd5de32b52e818714e13d40 Mon Sep 17 00:00:00 2001
From: Andreas Sturmlechner <asturm@gentoo.org>
Date: Mon, 1 Aug 2022 16:53:42 +0200
Subject: [PATCH] Add CMake option to build WITH_X11

We want to be able to build without X11 support even if some of the used
libraries may not work w/o X11 themselves yet or need to be built with
X11 support for other reverse dependencies.

HAVE_X11 already exists and is set automagically so far, but using
-DCMAKE_DISABLE_FIND_PACKAGE_X11 will break if any dependencies list X11
as required in their cmake config.

- Cleanup HAVE_* definitions a bit
- Clarify X11 PURPOSE a bit

Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>
---
 CMakeLists.txt           | 44 ++++++++++++++++++++++------------------
 processui/CMakeLists.txt |  4 ++--
 2 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 55938c4..5d4e085 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -65,25 +65,31 @@ ecm_setup_version(${PROJECT_VERSION}
                   SOVERSION 9
 )
 
-find_package(X11)
-set_package_properties(X11 PROPERTIES DESCRIPTION "X11 libraries"
-                        URL "https://www.x.org"
-                        TYPE OPTIONAL
-                        PURPOSE "Required for building the X11 based workspace"
-                    )
-if(X11_FOUND)
-    if (QT_MAJOR_VERSION STREQUAL "5")
-        find_package(Qt5X11Extras REQUIRED)
-    elseif (QT_MAJOR_VERSION STREQUAL "6")
-        find_package(Qt${QT_MAJOR_VERSION} ${REQUIRED_QT_VERSION} CONFIG REQUIRED Gui) # qtx11extras_p.h
-    endif()
-    set(HAVE_X11 1)
-    find_library(X11_XRes_LIB XRes ${X11_LIB_SEARCH_PATH})
-    find_path(X11_XRes_INCLUDE_PATH X11/extensions/XRes.h ${X11_INC_SEARCH_PATH})
-
-    if(X11_XRes_LIB AND X11_XRes_INCLUDE_PATH)
-        set(X11_XRes_FOUND TRUE)
+option(WITH_X11 "Build with X11 support." ON)
+if(WITH_X11)
+    find_package(X11)
+    set_package_properties(X11 PROPERTIES DESCRIPTION "X11 libraries"
+                            URL "https://www.x.org"
+                            TYPE OPTIONAL
+                            PURPOSE "Required for building Process UI with X11 support"
+                        )
+    if(X11_FOUND)
+        if (QT_MAJOR_VERSION STREQUAL "5")
+            find_package(Qt5X11Extras REQUIRED)
+        elseif (QT_MAJOR_VERSION STREQUAL "6")
+            find_package(Qt${QT_MAJOR_VERSION} ${REQUIRED_QT_VERSION} CONFIG REQUIRED Gui) # qtx11extras_p.h
+        endif()
+        set(HAVE_X11 1)
+        find_library(X11_XRes_LIB XRes ${X11_LIB_SEARCH_PATH})
+        find_path(X11_XRes_INCLUDE_PATH X11/extensions/XRes.h ${X11_INC_SEARCH_PATH})
+
+        if(X11_XRes_LIB AND X11_XRes_INCLUDE_PATH)
+            set(HAVE_XRES 1)
+        endif()
     endif()
+else()
+    set(HAVE_X11 0)
+    set(HAVE_XRES 0)
 endif()
 
 set(WEBENGINE_SCRIPTING_ENABLED FALSE)
@@ -122,8 +128,6 @@ if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
         PURPOSE "Used for reading hardware sensors")
 endif()
 
-set(HAVE_X11 ${X11_FOUND})
-set(HAVE_XRES ${X11_XRes_FOUND})
 configure_file(config-ksysguard.h.cmake ${CMAKE_CURRENT_BINARY_DIR}/config-ksysguard.h )
 
 option(BUILD_DESIGNERPLUGIN "Build plugin for Qt Designer" ON)
diff --git a/processui/CMakeLists.txt b/processui/CMakeLists.txt
index 2932733..c9bd800 100644
--- a/processui/CMakeLists.txt
+++ b/processui/CMakeLists.txt
@@ -30,7 +30,7 @@ ki18n_wrap_ui( processui_LIB_SRCS
 add_library(processui ${processui_LIB_SRCS})
 add_library(KSysGuard::ProcessUi ALIAS processui)
 
-if(X11_XRes_FOUND)
+if(HAVE_XRES)
     target_link_libraries(processui PRIVATE ${X11_XRes_LIB} ${X11_LIBRARIES})
     include_directories(${X11_XRes_INCLUDE_PATH})
 endif()
@@ -59,7 +59,7 @@ target_include_directories(processui
         "$<BUILD_INTERFACE:${libksysguard_SOURCE_DIR}>"
         "$<INSTALL_INTERFACE:${KDE_INSTALL_INCLUDEDIR}/ksysguard>"
 )
-if(X11_FOUND)
+if(HAVE_X11)
     if (QT_MAJOR_VERSION STREQUAL "5")
        target_link_libraries(processui PRIVATE Qt::X11Extras KF5::WindowSystem)
     else()
-- 
2.35.1