Prevent linking of AppMan modules into user plugins

As the AppMan modules are static libraries, linking any of them
into a QML plugin (that later gets loaded into the system-ui) will
lead to a bunch of problems:

1) due to symbol duplication and duplicate static data, a lot of
   singletons may exist twice
2) all static constructors (logging, crash-handling, etc.) are run
   a second time, overriding any custom configuration that was applied
   after config parsing.

If you are legitimately building a custom appman binary, a custom
launcher or a native app using launcher-lib, you need to flag this
via compile-time defines now:

Either AM_COMPILING_APPMAN or AM_COMPILING_LAUNCHER

AM_COMPILING_LAUNCHER is also used for native apps using launcher-lib.

Change-Id: I0c1a3fb7e0c7121f92d44c764c2c1eeb720e7041
Pick-to: 6.4
Reviewed-by: Dominik Holland <dominik.holland@qt.io>

8 files changed, 30 insertions, 3 deletions

diff --git a/examples/applicationmanager/application-features/doc/src/application-features.qdoc b/examples/applicationmanager/application-features/doc/src/application-features.qdoc
index a2ccb99b..ed9afad1 100644
--- a/examples/applicationmanager/application-features/doc/src/application-features.qdoc
+++ b/examples/applicationmanager/application-features/doc/src/application-features.qdoc
@@ -93,6 +93,14 @@ needs a \c type window property to differentiate between normal windows and popu
 This application only works in multi-process mode, as application processes cannot be started in
 single-process mode.
 
+Linking against the private application manager modules is prohibited by default to prevent
+potential problems with duplicate symbols coming from QML plugins. However here building against
+them is both intended and required, so we need to set the define \c AM_COMPILING_LAUNCHER:
+
+\quotefromfile applicationmanager/application-features/native/widgets/CMakeLists.txt
+\skipuntil /allows us to link against/
+\printuntil /AM_COMPILING_LAUNCHER/
+
 The C++ code for the native widgets application is as follows:
 
 \quotefromfile applicationmanager/application-features/native/widgets/main.cpp
diff --git a/examples/applicationmanager/application-features/native/widgets/CMakeLists.txt b/examples/applicationmanager/application-features/native/widgets/CMakeLists.txt
index b4c977da..52de895e 100644
--- a/examples/applicationmanager/application-features/native/widgets/CMakeLists.txt
+++ b/examples/applicationmanager/application-features/native/widgets/CMakeLists.txt
@@ -22,6 +22,10 @@ find_package(Qt6 COMPONENTS AppManLauncherPrivate)
 qt_add_executable(widgets
     main.cpp
 )
+
+# This define flags us as a "launcher" and allows us to link against the AppMan's private libraries
+target_compile_definitions(widgets PRIVATE AM_COMPILING_LAUNCHER)
+
 set_target_properties(widgets PROPERTIES
     WIN32_EXECUTABLE TRUE
     MACOSX_BUNDLE TRUE
diff --git a/examples/applicationmanager/application-features/native/widgets/widgets.pro b/examples/applicationmanager/application-features/native/widgets/widgets.pro
index 9a93277d..784f63cf 100644
--- a/examples/applicationmanager/application-features/native/widgets/widgets.pro
+++ b/examples/applicationmanager/application-features/native/widgets/widgets.pro
@@ -4,6 +4,9 @@ QT += widgets appman_launcher-private
 
 SOURCES = main.cpp
 
+# This define flags us as a "launcher" and allows us to link against the AppMan's private libraries
+DEFINES *= AM_COMPILING_LAUNCHER
+
 DESTDIR = $$OUT_PWD/../../apps/widgets
 
 target.path = $$[QT_INSTALL_EXAMPLES]/applicationmanager/application-features/apps/widgets
diff --git a/examples/applicationmanager/custom-appman/CMakeLists.txt b/examples/applicationmanager/custom-appman/CMakeLists.txt
index c3627257..972295d4 100644
--- a/examples/applicationmanager/custom-appman/CMakeLists.txt
+++ b/examples/applicationmanager/custom-appman/CMakeLists.txt
@@ -20,6 +20,10 @@ find_package(Qt6 COMPONENTS AppManMainPrivate)
 qt_add_executable(custom-appman
     custom-appman.cpp
 )
+
+# This define flags us as an "appman" and allows us to link against the AppMan's private libraries
+target_compile_definitions(custom-appman PRIVATE AM_COMPILING_APPMAN)
+
 set_target_properties(custom-appman PROPERTIES
     WIN32_EXECUTABLE FALSE
     MACOSX_BUNDLE FALSE
diff --git a/examples/applicationmanager/custom-appman/custom-appman.pro b/examples/applicationmanager/custom-appman/custom-appman.pro
index e1ebab9e..f6f4e294 100644
--- a/examples/applicationmanager/custom-appman/custom-appman.pro
+++ b/examples/applicationmanager/custom-appman/custom-appman.pro
@@ -6,6 +6,9 @@ CONFIG -= app_bundle qml_debug
 
 DEFINES += QT_MESSAGELOGCONTEXT
 
+# This define flags us as an "appman" and allows us to link against the AppMan's private libraries
+DEFINES *= AM_COMPILING_APPMAN
+
 QT = appman_main-private
 
 SOURCES = custom-appman.cpp
diff --git a/examples/applicationmanager/custom-appman/doc/src/custom-appman.qdoc b/examples/applicationmanager/custom-appman/doc/src/custom-appman.qdoc
index 0b74c1c9..dc16c90e 100644
--- a/examples/applicationmanager/custom-appman/doc/src/custom-appman.qdoc
+++ b/examples/applicationmanager/custom-appman/doc/src/custom-appman.qdoc
@@ -25,6 +25,14 @@ If you still require this behavior, this example provides a starting point that
 custom implementation upon. Keep in mind, that this custom application manager executable needs a
 System UI to display something on the screen, just like the standard \c appman executable.
 
+Linking against those application manager modules is prohibited by default to prevent
+potential problems with duplicate symbols coming from QML plugins. However here building against
+them is both intended and required, so we need to set the define \c AM_COMPILING_APPMAN:
+
+\quotefromfile applicationmanager/custom-appman/CMakeLists.txt
+\skipuntil /allows us to link against/
+\printuntil /AM_COMPILING_APPMAN/
+
 The following is a breakdown of the minimal code necessary:
 
 \quotefromfile applicationmanager/custom-appman/custom-appman.cpp
diff --git a/examples/applicationmanager/softwarecontainer-plugin/softwarecontainer.cpp b/examples/applicationmanager/softwarecontainer-plugin/softwarecontainer.cpp
index 4fcdb23d..a9c8ebe0 100644
--- a/examples/applicationmanager/softwarecontainer-plugin/softwarecontainer.cpp
+++ b/examples/applicationmanager/softwarecontainer-plugin/softwarecontainer.cpp
@@ -6,7 +6,6 @@
 #include <tuple>
 
 #include <QtDBus/QtDBus>
-#include <QtAppManCommon/global.h>
 #include <QJsonDocument>
 #include <QSocketNotifier>
 #include <QMetaObject>
@@ -52,7 +51,6 @@ const QDBusArgument &operator>>(const QDBusArgument &argument, QMap<QString,QStr
 QT_END_NAMESPACE
 
 
-QT_USE_NAMESPACE_AM
 
 // unfortunately, this is a copy of the code from debugwrapper.cpp
 static QStringList substituteCommand(const QStringList &debugWrapperCommand, const QString &program,
diff --git a/examples/applicationmanager/startup-plugin/startup-plugin.h b/examples/applicationmanager/startup-plugin/startup-plugin.h
index e5d073ce..f917c3dd 100644
--- a/examples/applicationmanager/startup-plugin/startup-plugin.h
+++ b/examples/applicationmanager/startup-plugin/startup-plugin.h
@@ -5,7 +5,6 @@
 
 #include <QLoggingCategory>
 #include <QtAppManPluginInterfaces/startupinterface.h>
-#include <QtAppManCommon/global.h>
 
 Q_DECLARE_LOGGING_CATEGORY(LogMe)