Fix our usage of CMake script mode in Windows configure

This is a preparation for adding the -help argument to
qt-configure-module.bat.

Consider the call
  qt-configure-module.bat path/to/qt-module -help
Internally, we called
  cmake ... -P .../QtWriteArgsFile.cmake path/to/qt-module -help
which was supposed to separate the arguments and write them into
config.opt.

However, passing arbitrary arguments after "-P script.cmake" only worked
by accident and is not supported.  As soon as arguments are passed that
are valid CMake arguments, like -help or -G, the CMake call would fail.

Now, we let configure.bat and qt-configure-module.bat write the
arguments as is into config.opt.in and let QtWriteArgsFile.cmake read
this file, separate the arguments and write config.opt.

Pick-to: 6.2
Task-number: QTBUG-95943
Change-Id: I80f298a2aaf55b0f79fed86320a055eb2d2b6faa
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

bin/qt-configure-module.bat.in

@@ -18,8 +18,9 @@ if not exist "%module_root%\CMakeLists.txt" (
 )
 
 set cmake_scripts_dir=%script_dir_path%\@__relative_path_to_cmake_scripts_dir@
-call "%script_dir_path%"\qt-cmake.bat -DSKIP_ARGS=1 -DOUT_FILE=config.opt ^
-    -P "%cmake_scripts_dir%\QtWriteArgsFile.cmake" %*
+echo %*>config.opt.in
+call "%script_dir_path%"\qt-cmake.bat -DSKIP_ARGS=1 -DIN_FILE=config.opt.in -DOUT_FILE=config.opt ^
+    -P "%cmake_scripts_dir%\QtWriteArgsFile.cmake"
 call "%script_dir_path%"\qt-cmake-private.bat -DOPTFILE=config.opt -DMODULE_ROOT="%module_root%" ^
     -DCMAKE_COMMAND="%script_dir_path%\qt-cmake-private.bat" ^
     -P "%cmake_scripts_dir%\QtProcessConfigureArgs.cmake"

cmake/QtWriteArgsFile.cmake

@@ -3,35 +3,30 @@
 # This is used for writing the config.opt file.
 #
 # This script takes the following arguments:
-# OUT_FILE: The output file.
+# IN_FILE: The input file. The whole command line as one string.
+# OUT_FILE: The output file. One argument per line.
 # SKIP_ARGS: Number of arguments to skip from the front of the arguments list.
 # IGNORE_ARGS: List of arguments to be ignored, i.e. that are not written.
 
 cmake_minimum_required(VERSION 3.3)
 
-# Look for the -P argument to determine the start of the actual script arguments
-math(EXPR stop "${CMAKE_ARGC} - 1")
-set(start 0)
-foreach(i RANGE 1 ${stop})
-    if(CMAKE_ARGV${i} STREQUAL "-P")
-        math(EXPR start "${i} + 2")
-        break()
-    endif()
-endforeach()
+# Read arguments from IN_FILE and separate them.
+file(READ "${IN_FILE}" raw_args)
+separate_arguments(args NATIVE_COMMAND "${raw_args}")
 
 # Skip arguments if requested
 if(DEFINED SKIP_ARGS)
-    math(EXPR start "${start} + ${SKIP_ARGS}")
+    foreach(i RANGE 1 ${SKIP_ARGS})
+        list(POP_FRONT args)
+    endforeach()
 endif()
 
 # Write config.opt
 set(content "")
-if(start LESS_EQUAL stop)
-    foreach(i RANGE ${start} ${stop})
-        set(arg ${CMAKE_ARGV${i}})
-        if(NOT arg IN_LIST IGNORE_ARGS)
-            string(APPEND content "${arg}\n")
-        endif()
-    endforeach()
-endif()
+foreach(arg IN LISTS args)
+    if(NOT arg IN_LIST IGNORE_ARGS)
+        string(APPEND content "${arg}\n")
+    endif()
+endforeach()
+
 file(WRITE "${OUT_FILE}" "${content}")

configure.bat

@@ -104,7 +104,8 @@ cd "%TOPQTDIR%"
 
 rem Write config.opt if we're not currently -redo'ing
 if "%rargs%" == "" (
-    cmake -DOUT_FILE=config.opt -DIGNORE_ARGS=-top-level -P "%QTSRC%\cmake\QtWriteArgsFile.cmake" %*
+    echo %*>config.opt.in
+    cmake -DIN_FILE=config.opt.in -DOUT_FILE=config.opt -DIGNORE_ARGS=-top-level -P "%QTSRC%\cmake\QtWriteArgsFile.cmake"
 )
 
 rem Launch CMake-based configure