os2: integrate the port into main tree.

include/SDL_config_os2.h

@@ -27,6 +27,7 @@
 
 #define SDL_AUDIO_DRIVER_DUMMY 1
 #define SDL_AUDIO_DRIVER_DISK 1
+#define SDL_AUDIO_DRIVER_OS2 1
 
 #define SDL_POWER_DISABLED  1
 #define SDL_JOYSTICK_DISABLED 1
@@ -34,6 +35,7 @@
 
 #define SDL_SENSOR_DUMMY 1
 #define SDL_VIDEO_DRIVER_DUMMY 1
+#define SDL_VIDEO_DRIVER_OS2 1
 
 /* Enable OpenGL support */
 /* #undef SDL_VIDEO_OPENGL */
@@ -41,10 +43,10 @@
 /* Enable Vulkan support */
 /* #undef SDL_VIDEO_VULKAN */
 
-#define SDL_LOADSO_DISABLED 1
-#define SDL_THREADS_DISABLED 1
-#define SDL_TIMERS_DISABLED 1
-#define SDL_FILESYSTEM_DUMMY 1
+#define SDL_THREAD_OS2 1
+#define SDL_LOADSO_OS2 1
+#define SDL_TIMER_OS2 1
+#define SDL_FILESYSTEM_OS2 1
 
 /* Enable assembly routines */
 #define SDL_ASSEMBLY_ROUTINES 1

include/SDL_syswm.h

@@ -106,6 +106,11 @@ typedef void *EGLSurface;
 #if defined(SDL_VIDEO_DRIVER_VIVANTE)
 #include "SDL_egl.h"
 #endif
+
+#if defined(SDL_VIDEO_DRIVER_OS2)
+#define INCL_WIN
+#include <os2.h>
+#endif
 #endif /* SDL_PROTOTYPES_ONLY */
 
 
@@ -186,6 +191,16 @@ struct SDL_SysWMmsg
             int dummy;
             /* No Vivante window events yet */
         } vivante;
+#endif
+#if defined(SDL_VIDEO_DRIVER_OS2)
+        struct
+        {
+            BOOL fFrame;                /**< TRUE if hwnd is a frame window */
+            HWND hwnd;                  /**< The window receiving the message */
+            ULONG msg;                  /**< The message identifier */
+            MPARAM mp1;                 /**< The first first message parameter */
+            MPARAM mp2;                 /**< The second first message parameter */
+        } os2;
 #endif
         /* Can't have an empty union */
         int dummy;
@@ -280,6 +295,14 @@ struct SDL_SysWMinfo
         } android;
 #endif
 
+#if defined(SDL_VIDEO_DRIVER_OS2)
+        struct
+        {
+            HWND hwnd;                  /**< The window handle */
+            HWND hwndFrame;             /**< The frame window handle */
+        } os2;
+#endif
+
 #if defined(SDL_VIDEO_DRIVER_VIVANTE)
         struct
         {