Add new interposer to make sure libjack is loaded on init

source/backend/plugin/CarlaPluginJack.cpp

@@ -121,13 +121,13 @@ protected:
 
             CarlaString ldpreload;
 
-            /*
+#ifdef HAVE_X11
             if (options.frontendWinId != 0)
             {
                 ldpreload = (CarlaString(options.binaryDir)
-                          + "/libcarla_interposer-x11.so");
+                          + "/libcarla_interposer-jack-x11.so");
             }
-            */
+#endif
 
             const ScopedEngineEnvironmentLocker _seel(kEngine);
 

source/interposer/Makefile

@@ -37,7 +37,9 @@ TARGETS += $(BINDIR)/libcarla_interposer-safe.so
 
 ifeq ($(HAVE_X11),true)
 OBJS    += $(OBJDIR)/interposer-x11.cpp.o
+OBJS    += $(OBJDIR)/interposer-jack-x11.cpp.o
 TARGETS += $(BINDIR)/libcarla_interposer-x11.so
+TARGETS += $(BINDIR)/libcarla_interposer-jack-x11.so
 endif
 endif
 
@@ -65,6 +67,11 @@ $(BINDIR)/libcarla_interposer-x11.so: $(OBJDIR)/interposer-x11.cpp.o
 	@echo "Linking libcarla_interposer-x11.so"
 	@$(CXX) $< $(SHARED) $(LINK_FLAGS) $(INTERPOSER_X11_LIBS) -o $@
 
+$(BINDIR)/libcarla_interposer-jack-x11.so: $(OBJDIR)/interposer-jack-x11.cpp.o
+	-@mkdir -p $(BINDIR)
+	@echo "Linking libcarla_interposer-jack-x11.so"
+	@$(CXX) $< $(SHARED) $(LINK_FLAGS) $(INTERPOSER_X11_LIBS) -o $@
+
 # ----------------------------------------------------------------------------------------------------------------------
 
 $(OBJDIR)/interposer-safe.cpp.o: interposer-safe.cpp
@@ -77,6 +84,11 @@ $(OBJDIR)/interposer-x11.cpp.o: interposer-x11.cpp
 	@echo "Compiling $<"
 	@$(CXX) $< $(BUILD_CXX_FLAGS) $(X11_FLAGS) -c -o $@
 
+$(OBJDIR)/interposer-jack-x11.cpp.o: interposer-jack-x11.cpp
+	-@mkdir -p $(OBJDIR)
+	@echo "Compiling $<"
+	@$(CXX) $< $(BUILD_CXX_FLAGS) $(X11_FLAGS) -c -o $@
+
 # ----------------------------------------------------------------------------------------------------------------------
 
 -include $(OBJS:%.o=%.d)

source/interposer/interposer-jack-x11.cpp

@@ -0,0 +1,110 @@
+/*
+ * Carla Interposer for X11 Window Mapping
+ * Copyright (C) 2014-2017 Filipe Coelho <falktx@falktx.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * For a full copy of the GNU General Public License see the doc/GPL.txt file.
+ */
+
+#include "CarlaUtils.hpp"
+
+#include <dlfcn.h>
+#include <X11/Xlib.h>
+
+struct ScopedLibOpen {
+    void* handle;
+
+    ScopedLibOpen()
+        : handle(dlopen("libjack.so.0", RTLD_NOW|RTLD_LOCAL)) {}
+
+    ~ScopedLibOpen()
+    {
+        if (handle != nullptr)
+            dlclose(handle);
+    }
+};
+
+// -----------------------------------------------------------------------
+// Function typedefs
+
+typedef int (*XMapWindowFunc)(Display*, Window);
+typedef int (*XUnmapWindowFunc)(Display*, Window);
+
+// -----------------------------------------------------------------------
+// Global counter so we only map the first (hopefully main) window
+
+static int sMapWindowCounter = 0;
+
+// -----------------------------------------------------------------------
+// Calling the real functions
+
+static int real_XMapWindow(Display* display, Window w)
+{
+    static const XMapWindowFunc func = (XMapWindowFunc)::dlsym(RTLD_NEXT, "XMapWindow");
+    CARLA_SAFE_ASSERT_RETURN(func != nullptr, 0);
+
+    return func(display, w);
+}
+
+static int real_XUnmapWindow(Display* display, Window w)
+{
+    static const XUnmapWindowFunc func = (XUnmapWindowFunc)::dlsym(RTLD_NEXT, "XUnmapWindow");
+    CARLA_SAFE_ASSERT_RETURN(func != nullptr, 0);
+
+    return func(display, w);
+}
+
+// -----------------------------------------------------------------------
+// Our custom functions
+
+CARLA_EXPORT
+int XMapWindow(Display* display, Window w)
+{
+    carla_stdout("------------------------------- XMapWindow called");
+
+    for (;;)
+    {
+        if (++sMapWindowCounter != 1)
+            break;
+
+        static const ScopedLibOpen slo;
+
+        if (const char* const winIdStr = std::getenv("CARLA_FRONTEND_WIN_ID"))
+        {
+            CARLA_SAFE_ASSERT_BREAK(winIdStr[0] != '\0');
+
+            const long long winIdLL(std::strtoll(winIdStr, nullptr, 16));
+            CARLA_SAFE_ASSERT_BREAK(winIdLL > 0);
+
+            const Window winId(static_cast<Window>(winIdLL));
+            XSetTransientForHint(display, w, static_cast<Window>(winId));
+
+            carla_stdout("Transient hint correctly applied before mapping window");
+        }
+
+        break;
+    }
+
+    return real_XMapWindow(display, w);
+}
+
+CARLA_EXPORT
+int XUnmapWindow(Display* display, Window w)
+{
+    carla_stdout("------------------------------- XUnmapWindow called");
+
+    --sMapWindowCounter;
+
+    return real_XUnmapWindow(display, w);
+}
+
+// -----------------------------------------------------------------------

source/interposer/interposer-x11.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla Interposer for X11 Window Mapping
- * Copyright (C) 2014-2015 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2014-2017 Filipe Coelho <falktx@falktx.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -63,15 +63,6 @@ int XMapWindow(Display* display, Window w)
         if (++sMapWindowCounter != 1)
             break;
 
-        static bool libjackopen = false;
-
-        if (! libjackopen && std::getenv("CARLA_LIBJACK_SETUP") != nullptr)
-        {
-            libjackopen = true;
-            dlopen("libjack.so.0", RTLD_NOW|RTLD_LOCAL);
-            carla_stdout("------------------------------- libjack opened");
-        }
-
         if (const char* const winIdStr = std::getenv("CARLA_ENGINE_OPTION_FRONTEND_WIN_ID"))
         {
             CARLA_SAFE_ASSERT_BREAK(winIdStr[0] != '\0');