SDL_rtf: cmake: install(CODE) has no CONFIG argument + don't use file(COPY_FILE)

From b5a9ad3808b19c6532ddd21edbbb07074c3625b8 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Fri, 22 Jul 2022 18:51:26 +0200
Subject: [PATCH] cmake: install(CODE) has no CONFIG argument + don't use
 file(COPY_FILE)

---
 CMakeLists.txt | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ef6705d..8d068ea 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -212,11 +212,15 @@ if(SDL2RTF_INSTALL)
         endif()
         # Only install a SDL2_rtf.pc file in Release mode
         install(CODE "
-        file(COPY_FILE \"${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtf-$<CONFIG>.pc\"
-            \"${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtf.pc\" ONLY_IF_DIFFERENT)
-        file(INSTALL DESTINATION \"\${CMAKE_INSTALL_PREFIX}/${PC_DESTDIR}\"
-            TYPE FILE
-            FILES \"${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtf.pc\")" CONFIG Release)
+            if(CMAKE_INSTALL_CONFIG_NAME MATCHES \"Release\")
+                # FIXME: use file(COPY_FILE) if minimum CMake version >= 3.21
+                execute_process(COMMAND \"\${CMAKE_COMMAND}\" -E copy_if_different
+                    \"${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtf-$<CONFIG>.pc\"
+                    \"${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtf.pc\")
+                file(INSTALL DESTINATION \"\${CMAKE_INSTALL_PREFIX}/${PC_DESTDIR}\"
+                    TYPE FILE
+                    FILES \"${CMAKE_CURRENT_BINARY_DIR}/SDL2_rtf.pc\")
+            endif()")
     endif()
 
     if(SDL2RTF_BUILD_SHARED_LIBS AND (APPLE OR (UNIX AND NOT ANDROID)))