2 files changed, 30 insertions, 8 deletions

diff --git a/source/blender/blenlib/intern/path_util.c b/source/blender/blenlib/intern/path_util.c
index 68e0f2c4026..d323098827b 100644
--- a/source/blender/blenlib/intern/path_util.c
+++ b/source/blender/blenlib/intern/path_util.c
@@ -1324,15 +1324,20 @@ const char *BLI_get_folder_version(const int id, const int ver, const bool do_ch
 #endif
 
 /**
- * Sets the specified environment variable to the specified value.
+ * Sets the specified environment variable to the specified value,
+ * and clears it if val == NULL.
  */
 void BLI_setenv(const char *env, const char *val)
 {
 	/* free windows */
 #if (defined(WIN32) || defined(WIN64)) && defined(FREE_WINDOWS)
-	char *envstr = MEM_mallocN(sizeof(char) * (strlen(env) + strlen(val) + 2), "envstr"); /* one for = another for \0 */
+	char *envstr;
+
+	if (val)
+		envstr = BLI_sprintfN("%s=%s", env, val);
+	else
+		envstr = BLI_sprintfN("%s=", env);
 
-	sprintf(envstr, "%s=%s", env, val);
 	putenv(envstr);
 	MEM_freeN(envstr);
 
@@ -1343,7 +1348,10 @@ void BLI_setenv(const char *env, const char *val)
 
 #else
 	/* linux/osx/bsd */
-	setenv(env, val, 1);
+	if (val)
+		setenv(env, val, 1);
+	else
+		unsetenv(env);
 #endif
 }
 
diff --git a/source/gameengine/GameLogic/Joystick/SCA_Joystick.cpp b/source/gameengine/GameLogic/Joystick/SCA_Joystick.cpp
index 64ab0af4d26..793ce6a7b83 100644
--- a/source/gameengine/GameLogic/Joystick/SCA_Joystick.cpp
+++ b/source/gameengine/GameLogic/Joystick/SCA_Joystick.cpp
@@ -39,6 +39,8 @@
 #include "SCA_Joystick.h"
 #include "SCA_JoystickPrivate.h"
 
+#include "BLI_path_util.h"
+
 SCA_Joystick::SCA_Joystick(short int index)
 	:
 	m_joyindex(index),
@@ -88,14 +90,26 @@ SCA_Joystick *SCA_Joystick::GetInstance( short int joyindex )
 	if (m_refCount == 0) 
 	{
 		int i;
+
 		/* The video subsystem is required for joystick input to work. However,
-		 * when GHOST is running under SDL, video is initialized elsewhere.
-		 * Do this once only. */
+		 * when GHOST is running under SDL, video is initialized elsewhere. We
+		 * also need to set the videodriver to dummy, and do it here to avoid
+		 * interfering with addons that may use SDL too.
+		 *
+		 * We also init SDL once only. */
 #  ifdef WITH_GHOST_SDL
-		if (SDL_InitSubSystem(SDL_INIT_JOYSTICK) == -1 ) {
+		int success = (SDL_InitSubSystem(SDL_INIT_JOYSTICK) != -1 );
 #  else
-		if (SDL_InitSubSystem(SDL_INIT_JOYSTICK | SDL_INIT_VIDEO) == -1 ) {
+		/* set and restore environment variable */
+		char *videodriver = getenv("SDL_VIDEODRIVER");
+		BLI_setenv("SDL_VIDEODRIVER", "dummy");
+
+		int success = (SDL_InitSubSystem(SDL_INIT_JOYSTICK | SDL_INIT_VIDEO) != -1 );
+
+		BLI_setenv("SDL_VIDEODRIVER", videodriver);
 #  endif
+
+		if (!success) {
 			JOYSTICK_ECHO("Error-Initializing-SDL: " << SDL_GetError());
 			return NULL;
 		}