4 files changed, 235 insertions, 14 deletions
diff --git a/cmake/ECMQueryQt.cmake b/cmake/ECMQueryQt.cmake
new file mode 100644
index 00000000..98eb5008
--- /dev/null
+++ b/cmake/ECMQueryQt.cmake
@@ -0,0 +1,100 @@
+# SPDX-FileCopyrightText: 2014 Rohan Garg <rohan16garg@gmail.com>
+# SPDX-FileCopyrightText: 2014 Alex Merry <alex.merry@kde.org>
+# SPDX-FileCopyrightText: 2014-2016 Aleix Pol <aleixpol@kde.org>
+# SPDX-FileCopyrightText: 2017 Friedrich W. H. Kossebau <kossebau@kde.org>
+# SPDX-FileCopyrightText: 2022 Ahmad Samir <a.samir78@gmail.com>
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#[=======================================================================[.rst:
+ECMQueryQt
+---------------
+This module can be used to query the installation paths used by Qt.
+
+For Qt5 this uses ``qmake``, and for Qt6 this used ``qtpaths`` (the latter has built-in
+support to query the paths of a target platform when cross-compiling).
+
+This module defines the following function:
+::
+
+    ecm_query_qt(<result_variable> <qt_variable> [TRY])
+
+Passing ``TRY`` will result in the method not making the build fail if the executable
+used for querying has not been found, but instead simply print a warning message and
+return an empty string.
+
+Example usage:
+
+.. code-block:: cmake
+
+    include(ECMQueryQt)
+    ecm_query_qt(bin_dir QT_INSTALL_BINS)
+
+If the call succeeds ``${bin_dir}`` will be set to ``<prefix>/path/to/bin/dir`` (e.g.
+``/usr/lib64/qt/bin/``).
+
+Since: 5.93
+#]=======================================================================]
+
+include(${CMAKE_CURRENT_LIST_DIR}/QtVersionOption.cmake)
+include(CheckLanguage)
+check_language(CXX)
+if (CMAKE_CXX_COMPILER)
+    # Enable the CXX language to let CMake look for config files in library dirs.
+    # See: https://gitlab.kitware.com/cmake/cmake/-/issues/23266
+    enable_language(CXX)
+endif()
+
+if (QT_MAJOR_VERSION STREQUAL "5")
+    # QUIET to accommodate the TRY option
+    find_package(Qt${QT_MAJOR_VERSION}Core QUIET)
+    if(TARGET Qt5::qmake)
+        get_target_property(_qmake_executable_default Qt5::qmake LOCATION)
+
+        set(QUERY_EXECUTABLE ${_qmake_executable_default}
+            CACHE FILEPATH "Location of the Qt5 qmake executable")
+        set(_exec_name_text "Qt5 qmake")
+        set(_cli_option "-query")
+    endif()
+elseif(QT_MAJOR_VERSION STREQUAL "6")
+    # QUIET to accommodate the TRY option
+    find_package(Qt6 COMPONENTS CoreTools QUIET CONFIG)
+    if (TARGET Qt6::qtpaths)
+        get_target_property(_qtpaths_executable Qt6::qtpaths LOCATION)
+
+        set(QUERY_EXECUTABLE ${_qtpaths_executable}
+            CACHE FILEPATH "Location of the Qt6 qtpaths executable")
+        set(_exec_name_text "Qt6 qtpaths")
+        set(_cli_option "--query")
+    endif()
+endif()
+
+function(ecm_query_qt result_variable qt_variable)
+    set(options TRY)
+    set(oneValueArgs)
+    set(multiValueArgs)
+
+    cmake_parse_arguments(ARGS "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+
+    if(NOT QUERY_EXECUTABLE)
+        if(ARGS_TRY)
+            set(${result_variable} "" PARENT_SCOPE)
+            message(STATUS "No ${_exec_name_text} executable found. Can't check ${qt_variable}")
+            return()
+        else()
+            message(FATAL_ERROR "No ${_exec_name_text} executable found. Can't check ${qt_variable} as required")
+        endif()
+    endif()
+    execute_process(
+        COMMAND ${QUERY_EXECUTABLE} ${_cli_option} "${qt_variable}"
+        RESULT_VARIABLE return_code
+        OUTPUT_VARIABLE output
+    )
+    if(return_code EQUAL 0)
+        string(STRIP "${output}" output)
+        file(TO_CMAKE_PATH "${output}" output_path)
+        set(${result_variable} "${output_path}" PARENT_SCOPE)
+    else()
+        message(WARNING "Failed call: ${_command} \"${qt_variable}\"")
+        message(FATAL_ERROR "${_exec_name_text} call failed: ${return_code}")
+    endif()
+endfunction()
diff --git a/cmake/QMakeQuery.cmake b/cmake/QMakeQuery.cmake
deleted file mode 100644
index bf0fe967..00000000
--- a/cmake/QMakeQuery.cmake
+++ /dev/null
@@ -1,14 +0,0 @@
-if(__QMAKEQUERY_CMAKE__)
-    return()
-endif()
-set(__QMAKEQUERY_CMAKE__ TRUE)
-
-get_target_property(QMAKE_EXECUTABLE Qt5::qmake LOCATION)
-
-function(QUERY_QMAKE VAR RESULT)
-    exec_program(${QMAKE_EXECUTABLE} ARGS "-query ${VAR}" RETURN_VALUE return_code OUTPUT_VARIABLE output )
-    if(NOT return_code)
-        file(TO_CMAKE_PATH "${output}" output)
-        set(${RESULT} ${output} PARENT_SCOPE)
-    endif(NOT return_code)
-endfunction(QUERY_QMAKE)
diff --git a/cmake/QtVersionOption.cmake b/cmake/QtVersionOption.cmake
new file mode 100644
index 00000000..1390f9db
--- /dev/null
+++ b/cmake/QtVersionOption.cmake
@@ -0,0 +1,38 @@
+#.rst:
+# QtVersionOption
+# ---------------
+#
+# Adds a build option to select the major Qt version if necessary,
+# that is, if the major Qt version has not yet been determined otherwise
+# (e.g. by a corresponding find_package() call).
+#
+# This module is typically included by other modules requiring knowledge
+# about the major Qt version.
+#
+# ``QT_MAJOR_VERSION`` is defined to either be "5" or "6".
+#
+#
+# Since 5.82.0.
+
+#=============================================================================
+# SPDX-FileCopyrightText: 2021 Volker Krause <vkrause@kde.org>
+#
+# SPDX-License-Identifier: BSD-3-Clause
+
+if (DEFINED QT_MAJOR_VERSION)
+    return()
+endif()
+
+if (TARGET Qt5::Core)
+    set(QT_MAJOR_VERSION 5)
+elseif (TARGET Qt6::Core)
+    set(QT_MAJOR_VERSION 6)
+else()
+    option(BUILD_WITH_QT6 "Build against Qt 6" OFF)
+
+    if (BUILD_WITH_QT6)
+        set(QT_MAJOR_VERSION 6)
+    else()
+        set(QT_MAJOR_VERSION 5)
+    endif()
+endif()
diff --git a/cmake/QtVersionlessBackport.cmake b/cmake/QtVersionlessBackport.cmake
new file mode 100644
index 00000000..46792db5
--- /dev/null
+++ b/cmake/QtVersionlessBackport.cmake
@@ -0,0 +1,97 @@
+#=============================================================================
+# Copyright 2005-2011 Kitware, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# * Redistributions of source code must retain the above copyright
+#   notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+#   notice, this list of conditions and the following disclaimer in the
+#   documentation and/or other materials provided with the distribution.
+#
+# * Neither the name of Kitware, Inc. nor the names of its
+#   contributors may be used to endorse or promote products derived
+#   from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#=============================================================================
+
+# From Qt5CoreMacros.cmake
+
+function(qt_generate_moc)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_generate_moc(${ARGV})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_generate_moc(${ARGV})
+    endif()
+endfunction()
+
+function(qt_wrap_cpp outfiles)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_wrap_cpp("${outfiles}" ${ARGN})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_wrap_cpp("${outfiles}" ${ARGN})
+    endif()
+    set("${outfiles}" "${${outfiles}}" PARENT_SCOPE)
+endfunction()
+
+function(qt_add_binary_resources)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_add_binary_resources(${ARGV})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_add_binary_resources(${ARGV})
+    endif()
+endfunction()
+
+function(qt_add_resources outfiles)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_add_resources("${outfiles}" ${ARGN})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_add_resources("${outfiles}" ${ARGN})
+    endif()
+    set("${outfiles}" "${${outfiles}}" PARENT_SCOPE)
+endfunction()
+
+function(qt_add_big_resources outfiles)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_add_big_resources(${outfiles} ${ARGN})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_add_big_resources(${outfiles} ${ARGN})
+    endif()
+    set("${outfiles}" "${${outfiles}}" PARENT_SCOPE)
+endfunction()
+
+function(qt_import_plugins)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_import_plugins(${ARGV})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_import_plugins(${ARGV})
+    endif()
+endfunction()
+
+
+# From Qt5WidgetsMacros.cmake
+
+function(qt_wrap_ui outfiles)
+    if(QT_VERSION_MAJOR EQUAL 5)
+        qt5_wrap_ui("${outfiles}" ${ARGN})
+    elseif(QT_VERSION_MAJOR EQUAL 6)
+        qt6_wrap_ui("${outfiles}" ${ARGN})
+    endif()
+    set("${outfiles}" "${${outfiles}}" PARENT_SCOPE)
+endfunction()
+