Generate information about user-facing applications in build dir

When packaging different Qt versions for Linux distributions (or any
distribution with a common bin dir), Qt tools cannot be installed to
/usr/bin, because the executable names of the different Qt versions
clash.

To solve this conflict, our recommendation is to install Qt's tools to
/usr/lib/qt6/bin and to create versioned symlinks to user-facing tools
in /usr/bin.

User-facing tools are tools that are supposed to be started manually by
the user. They are marked in Qt's build system. Distro package
maintainers can now configure with
  -DCMAKE_INSTALL_PREFIX=/usr
  -DINSTALL_BINDIR=/usr/lib/qt6/bin
  -DINSTALL_PUBLICBINDIR=/usr/bin
and will find a file called user_facing_tool_links.txt in the build
directory after the cmake run. Nothing will be installed to
INSTALL_PUBLICBINDIR.

Each line of user_facing_tool_links.txt consists of the installation
path of a user-facing application followed by a space and the versioned
link name in INSTALL_PUBLICBINDIR.

Example content:
/usr/lib/qt6/bin/qmake /usr/bin/qmake6

To actually create the versioned symlinks, the content of this file can
be fed to ln like this:
  xargs ln -s < build-dir/user_facing_tool_links.txt

Or the package maintainer may decide to do something completely
different as suits their needs.

This patch adds the USER_FACING argument to qt_internal_add_tool to mark
tools as user-facing. In addition, every Qt created by
qt_internal_add_app is treated as user-facing.

The only tool this patch marks as user-facing in qtbase is qmake.

Pick-to: 6.1
Fixes: QTBUG-89170
Change-Id: I52673b1c8d40f40f56a74203065553115e2c4de5
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

1 files changed, 8 insertions, 1 deletions

diff --git a/cmake/QtToolHelpers.cmake b/cmake/QtToolHelpers.cmake
index 869a6e3300..e052479b6c 100644
--- a/cmake/QtToolHelpers.cmake
+++ b/cmake/QtToolHelpers.cmake
@@ -2,6 +2,9 @@
 # The BOOTSTRAP option allows building it as standalone program, otherwise
 # it will be linked against QtCore.
 #
+# USER_FACING can be passed to mark the tool as a program that is supposed to be
+# started directly by users.
+#
 # We must pass this function a target name obtained from
 # qt_get_tool_target_name like this:
 #     qt_get_tool_target_name(target_name my_tool)
@@ -22,7 +25,7 @@ function(qt_internal_add_tool target_name)
     qt_tool_target_to_name(name ${target_name})
     set(one_value_keywords TOOLS_TARGET EXTRA_CMAKE_FILES INSTALL_DIR
                            ${__default_target_info_args})
-    qt_parse_all_arguments(arg "qt_add_tool" "BOOTSTRAP;NO_INSTALL"
+    qt_parse_all_arguments(arg "qt_add_tool" "BOOTSTRAP;NO_INSTALL;USER_FACING"
                                "${one_value_keywords}"
                                "${__default_private_args}" ${ARGN})
 
@@ -175,6 +178,10 @@ function(qt_internal_add_tool target_name)
         )
     endif()
 
+    if(arg_USER_FACING)
+        set_property(GLOBAL APPEND PROPERTY QT_USER_FACING_TOOL_TARGETS ${target_name})
+    endif()
+
     # If building with a multi-config configuration, the main configuration tool will be placed in
     # ./bin, while the rest will be in <CONFIG> specific subdirectories.
     qt_get_tool_cmake_configuration(tool_cmake_configuration)