Fixed bug 3478 - Patch Haiku to use dlopen instead of load_add_on

Kai Sterker

SDL2 on Haiku so far uses Haiku-specific APIs for loading dynamic objects as add-ons, instead of using dlopen to load them as libraries. This, for example, leads to SDL_mixer not being able to load its audio backends, when compiled with standard settings.

As discussed at https://www.freelists.org/post/haikuports/SDL2-mixer-ogg-music-not-playing-and-other-stuff,2 , the best way to deal with this would be using dlopen instead of load_add_on. The following patch implements this change by dropping the Haiku-specific bits and using dlopen instead.

configure.in

@@ -3229,6 +3229,7 @@ AC_HELP_STRING([--enable-render-d3d], [enable the Direct3D render driver [[defau
         CheckDummyVideo
         CheckDiskAudio
         CheckDummyAudio
+        CheckDLOPEN
         CheckHaikuVideo
         CheckHaikuGL
         CheckPTHREAD
@@ -3251,12 +3252,6 @@ AC_HELP_STRING([--enable-render-d3d], [enable the Direct3D render driver [[defau
             SOURCES="$SOURCES $srcdir/src/timer/haiku/*.c"
             have_timers=yes
         fi
-        # Set up files for the shared object loading library
-        if test x$enable_loadso = xyes; then
-            AC_DEFINE(SDL_LOADSO_HAIKU, 1, [ ])
-            SOURCES="$SOURCES $srcdir/src/loadso/haiku/*.c"
-            have_loadso=yes
-        fi
         # Set up files for the system power library
         if test x$enable_power = xyes; then
             AC_DEFINE(SDL_POWER_HAIKU, 1, [ ])