src/SDL12_compat.c

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2013 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/

/* This file contains functions for backwards compatibility with SDL 1.2 */

#include "SDL20_include_wrapper.h"

#if !SDL_VERSION_ATLEAST(2,0,0)
#error You need to compile against SDL 2.0 headers.
#endif

/*
 * We report the library version as 1.2.$(SDL12_COMPAT_VERSION). This number
 *  should be way ahead of what SDL-1.2 Classic would report, so apps can
 *  decide if they're running under the compat layer, if they really care.
 */
#define SDL12_COMPAT_VERSION 50

#include <stdarg.h>

// !!! IMPLEMENT_ME SDL_ConvertSurface
// !!! IMPLEMENT_ME SDL_GetKeyName
// !!! IMPLEMENT_ME SDL_GetKeyState
// !!! IMPLEMENT_ME SDL_GetModState
// !!! IMPLEMENT_ME SDL_GetRelativeMouseState
// !!! IMPLEMENT_ME SDL_LockSurface
// !!! IMPLEMENT_ME SDL_LowerBlit
// !!! IMPLEMENT_ME SDL_SetColorKey
// !!! IMPLEMENT_ME SDL_SetModState
// !!! IMPLEMENT_ME SDL_SoftStretch
// !!! IMPLEMENT_ME SDL_UnlockSurface
// !!! IMPLEMENT_ME SDL_UpperBlit
// !!! IMPLEMENT_ME X11_KeyToUnicode


#define SDL20_SYM(rc,fn,params,args,ret) \
    typedef rc (SDLCALL *SDL20_##fn##_t) params; \
    static SDL20_##fn##_t SDL20_##fn = NULL;
#define SDL20_SYM_PASSTHROUGH(rc,fn,params,args,ret) \
    SDL20_SYM(rc,fn,params,args,ret)
#include "SDL20_syms.h"
#undef SDL20_SYM_PASSTHROUGH
#undef SDL20_SYM

typedef int (SDLCALL *SDL20_SetError_t)(const char *fmt, ...);
static SDL20_SetError_t SDL20_SetError = NULL;

/* Things that _should_ be binary compatible pass right through... */
#define SDL20_SYM(rc,fn,params,args,ret)
#define SDL20_SYM_PASSTHROUGH(rc,fn,params,args,ret) \
    DECLSPEC rc SDLCALL SDL_##fn params { ret SDL20_##fn args; }
#include "SDL20_syms.h"
#undef SDL20_SYM_PASSTHROUGH
#undef SDL20_SYM


/* these are macros (etc) in the SDL headers, so make our own. */
#define SDL20_OutOfMemory() SDL20_Error(SDL_ENOMEM)
#define SDL20_Unsupported() SDL20_Error(SDL_UNSUPPORTED)
#define SDL20_InvalidParamError(param) SDL20_SetError("Parameter '%s' is invalid", (param))
#define SDL20_zero(x) SDL20_memset(&(x), 0, sizeof((x)))
#define SDL20_zerop(x) SDL20_memset((x), 0, sizeof(*(x)))
#define SDL_ReportAssertion SDL20_ReportAssertion

#define SDL12_DEFAULT_REPEAT_DELAY 500
#define SDL12_DEFAULT_REPEAT_INTERVAL 30

#define SDL12_INIT_TIMER       0x00000001
#define SDL12_INIT_AUDIO       0x00000010
#define SDL12_INIT_VIDEO       0x00000020
#define SDL12_INIT_CDROM       0x00000100
#define SDL12_INIT_JOYSTICK    0x00000200
#define SDL12_INIT_NOPARACHUTE 0x00100000
#define SDL12_INIT_EVENTTHREAD 0x01000000
#define SDL12_INIT_EVERYTHING  0x0000FFFF

typedef struct SDL12_Palette
{
    int       ncolors;
    SDL_Color *colors;
} SDL12_Palette;

typedef struct SDL12_PixelFormat
{
    SDL12_Palette *palette;
    Uint8 BitsPerPixel;
    Uint8 BytesPerPixel;
    Uint8 Rloss;
    Uint8 Gloss;
    Uint8 Bloss;
    Uint8 Aloss;
    Uint8 Rshift;
    Uint8 Gshift;
    Uint8 Bshift;
    Uint8 Ashift;
    Uint32 Rmask;
    Uint32 Gmask;
    Uint32 Bmask;
    Uint32 Amask;
    Uint32 colorkey;
    Uint8 alpha;
} SDL12_PixelFormat;

typedef struct SDL12_Surface
{
    Uint32 flags;
    SDL12_PixelFormat *format;
    int w;
    int h;
    Uint16 pitch;
    void *pixels;
    int offset;
    SDL_Surface *surface20; /* the real SDL 1.2 has an opaque pointer to a platform-specific thing here named "hwdata". */
    SDL_Rect clip_rect;
    Uint32 unused1;
    Uint32 locked;
    void *blitmap;
    unsigned int format_version;
    int refcount;
} SDL12_Surface;

typedef struct
{
    Uint32 hw_available :1;
    Uint32 wm_available :1;
    Uint32 UnusedBits1  :6;
    Uint32 UnusedBits2  :1;
    Uint32 blit_hw      :1;
    Uint32 blit_hw_CC   :1;
    Uint32 blit_hw_A    :1;
    Uint32 blit_sw      :1;
    Uint32 blit_sw_CC   :1;
    Uint32 blit_sw_A    :1;
    Uint32 blit_fill    :1;
    Uint32 UnusedBits3  :16;
    Uint32 video_mem;
    SDL_PixelFormat *vfmt;
    int current_w;
    int current_h;
} SDL12_VideoInfo;


#define SDL12_HWSURFACE 0x00000001
#define SDL12_ASYNCBLIT 0x00000004
#define SDL12_ANYFORMAT 0x10000000
#define SDL12_HWPALETTE 0x20000000
#define SDL12_DOUBLEBUF 0x40000000
#define SDL12_FULLSCREEN 0x80000000
#define SDL12_OPENGL 0x00000002
#define SDL12_OPENGLBLIT 0x0000000A
#define SDL12_RESIZABLE 0x00000010
#define SDL12_NOFRAME 0x00000020
#define SDL12_HWACCEL 0x00000100
#define SDL12_SRCCOLORKEY 0x00001000
#define SDL12_RLEACCELOK 0x00002000
#define SDL12_RLEACCEL 0x00004000
#define SDL12_SRCALPHA 0x00010000
#define SDL12_PREALLOC 0x01000000

typedef enum
{
    SDL12_NOEVENT = 0,
    SDL12_ACTIVEEVENT,
    SDL12_KEYDOWN,
    SDL12_KEYUP,
    SDL12_MOUSEMOTION,
    SDL12_MOUSEBUTTONDOWN,
    SDL12_MOUSEBUTTONUP,
    SDL12_JOYAXISMOTION,
    SDL12_JOYBALLMOTION,
    SDL12_JOYHATMOTION,
    SDL12_JOYBUTTONDOWN,
    SDL12_JOYBUTTONUP,
    SDL12_QUIT,
    SDL12_SYSWMEVENT,
    SDL12_EVENT_RESERVEDA,
    SDL12_EVENT_RESERVEDB,
    SDL12_VIDEORESIZE,
    SDL12_VIDEOEXPOSE,
    SDL12_USEREVENT = 24,
    SDL12_NUMEVENTS = 32
} SDL12_EventType;


#define SDL12_APPMOUSEFOCUS (1<<0)
#define SDL12_APPINPUTFOCUS (1<<1)
#define SDL12_APPACTIVE     (1<<2)

typedef struct
{
    Uint8 type;
    Uint8 gain;
    Uint8 state;
} SDL12_ActiveEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 state;
    //FIXME: SDL12_keysym keysym;
} SDL12_KeyboardEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 state;
    Uint16 x, y;
    Sint16 xrel;
    Sint16 yrel;
} SDL12_MouseMotionEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 button;
    Uint8 state;
    Uint16 x, y;
} SDL12_MouseButtonEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 axis;
    Sint16 value;
} SDL12_JoyAxisEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 ball;
    Sint16 xrel;
    Sint16 yrel;
} SDL12_JoyBallEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 hat;
    Uint8 value;
} SDL12_JoyHatEvent;

typedef struct
{
    Uint8 type;
    Uint8 which;
    Uint8 button;
    Uint8 state;
} SDL12_JoyButtonEvent;

typedef struct
{
    Uint8 type;
    int w;
    int h;
} SDL12_ResizeEvent;

typedef struct
{
    Uint8 type;
} SDL12_ExposeEvent;

typedef struct
{
    Uint8 type;
} SDL12_QuitEvent;

typedef struct
{
    Uint8 type;
    int code;
    void *data1;
    void *data2;
} SDL12_UserEvent;

typedef struct
{
    Uint8 type;
    void *msg;
} SDL12_SysWMEvent;

typedef union
{
    Uint8 type;
    SDL12_ActiveEvent active;
    SDL12_KeyboardEvent key;
    SDL12_MouseMotionEvent motion;
    SDL12_MouseButtonEvent button;
    SDL12_JoyAxisEvent jaxis;
    SDL12_JoyBallEvent jball;
    SDL12_JoyHatEvent jhat;
    SDL12_JoyButtonEvent jbutton;
    SDL12_ResizeEvent resize;
    SDL12_ExposeEvent expose;
    SDL12_QuitEvent quit;
    SDL12_UserEvent user;
    SDL12_SysWMEvent syswm;
} SDL12_Event;

typedef int (SDLCALL *SDL12_EventFilter)(const SDL12_Event *event12);
static int EventFilter20to12(void *data, SDL_Event *event20);

typedef Uint32 (SDLCALL *SDL12_TimerCallback)(Uint32 interval);
typedef SDL_TimerCallback SDL12_NewTimerCallback;

typedef struct
{
    SDL_Rect area;
    Sint16 hot_x;
    Sint16 hot_y;
    Uint8 *data;
    Uint8 *mask;
    Uint8 *save[2];
    SDL_Cursor *wm_cursor;  /* the real SDL 1.2 has an opaque pointer to a platform-specific cursor here. */
} SDL12_Cursor;

typedef enum
{
    SDL12_GL_RED_SIZE,
    SDL12_GL_GREEN_SIZE,
    SDL12_GL_BLUE_SIZE,
    SDL12_GL_ALPHA_SIZE,
    SDL12_GL_BUFFER_SIZE,
    SDL12_GL_DOUBLEBUFFER,
    SDL12_GL_DEPTH_SIZE,
    SDL12_GL_STENCIL_SIZE,
    SDL12_GL_ACCUM_RED_SIZE,
    SDL12_GL_ACCUM_GREEN_SIZE,
    SDL12_GL_ACCUM_BLUE_SIZE,
    SDL12_GL_ACCUM_ALPHA_SIZE,
    SDL12_GL_STEREO,
    SDL12_GL_MULTISAMPLEBUFFERS,
    SDL12_GL_MULTISAMPLESAMPLES,
    SDL12_GL_ACCELERATED_VISUAL,
    SDL12_GL_SWAP_CONTROL,
    SDL12_GL_MAX_ATTRIBUTE
} SDL12_GLattr;

static SDL12_VideoInfo VideoInfo;
static SDL_Window *VideoWindow20 = NULL;
static SDL12_Surface *WindowSurface = NULL;
static SDL12_Surface *VideoSurface = NULL;
static SDL12_Surface *ShadowSurface = NULL;
static SDL12_Surface *PublicSurface = NULL;
static SDL_GLContext *VideoContext = NULL;
static Uint32 VideoFlags = 0;
static SDL_Rect VideoViewport;
static char *WindowTitle = NULL;
static char *WindowIconTitle = NULL;
static SDL_Surface *VideoIcon;
static int EnabledUnicode = 0;
static int VideoDisplayIndex = 0;
static int CDRomInit = 0;
static SDL12_EventFilter EventFilter12 = NULL;
static SDL12_Cursor *CurrentCursor = NULL;
static Uint8 EventStates[SDL12_NUMEVENTS];
static int SwapInterval = 0;

// !!! FIXME: need a mutex for the event queue.
#define SDL12_MAXEVENTS 128
typedef struct EventQueueType
{
    SDL12_Event event12;
    struct EventQueueType *next;
} EventQueueType;

static EventQueueType EventQueuePool[SDL12_MAXEVENTS];
static EventQueueType *EventQueueHead = NULL;
static EventQueueType *EventQueueTail = NULL;
static EventQueueType *EventQueueAvailable = NULL;


/* Obviously we can't use SDL_LoadObject() to load SDL2.  :)  */
#if defined(_WINDOWS)
    #define WIN32_LEAN_AND_MEAN 1
    #include <windows.h>
    #define SDL20_LIBNAME "SDL2.dll"
    static HANDLE Loaded_SDL20 = NULL;
    #define LoadSDL20Library() ((Loaded_SDL20 = LoadLibraryA(SDL20_LIBNAME)) != NULL)
    #define LookupSDL20Sym(sym) GetProcAddress(Loaded_SDL20, sym)
    #define CloseSDL20Library() { { if (Loaded_SDL20) { FreeLibrary(Loaded_SDL20); Loaded_SDL20 = NULL; } }
#elif defined(unix) || defined(__APPLE__)
    #include <dlfcn.h>
    #ifdef __APPLE__
    #define SDL20_LIBNAME "libSDL2.dylib"
    #else
    #define SDL20_LIBNAME "libSDL2-2.0.so.0"
    #endif
    static void *Loaded_SDL20 = NULL;
    #define LoadSDL20Library() ((Loaded_SDL20 = dlopen(SDL20_LIBNAME, RTLD_LOCAL)) != NULL)
    #define LookupSDL20Sym(sym) dlsym(Loaded_SDL20, sym)
    #define CloseSDL20Library() { if (Loaded_SDL20) { dlclose(Loaded_SDL20); Loaded_SDL20 = NULL; } }
#else
    #error Please define your platform.
#endif

static void *
LoadSDL20Symbol(const char *fn, int *okay)
{
    void *retval = NULL;
    if (*okay)  /* only bother trying if we haven't previously failed. */
    {
        retval = LookupSDL20Sym(fn);
        if (retval == NULL)
            *okay = 0;
    }
    return retval;
}

static void
UnloadSDL20(void)
{
    #define SDL20_SYM(rc,fn,params,args,ret) SDL20_##fn = NULL;
    #define SDL20_SYM_PASSTHROUGH(rc,fn,params,args,ret) SDL20_SYM(rc,fn,params,args,ret)
    #include "SDL20_syms.h"
    #undef SDL20_SYM_PASSTHROUGH
    #undef SDL20_SYM
    SDL20_SetError = NULL;
    CloseSDL20Library();
}

static int
LoadSDL20(void)
{
    int okay = 1;
    if (!Loaded_SDL20)
    {
        okay = LoadSDL20Library();
        #define SDL20_SYM(rc,fn,params,args,ret) SDL20_##fn = (SDL20_##fn##_t) LoadSDL20Symbol("SDL_" #fn, &okay);
        #define SDL20_SYM_PASSTHROUGH(rc,fn,params,args,ret) SDL20_SYM(rc,fn,params,args,ret)
        #include "SDL20_syms.h"
        #undef SDL20_SYM_PASSTHROUGH
        #undef SDL20_SYM
        SDL20_SetError = (SDL20_SetError_t) LoadSDL20Symbol("SDL_SetError", &okay);
        if (!okay)
            UnloadSDL20();
    }
    return okay;
}

DECLSPEC const SDL_version * SDLCALL
SDL_Linked_Version(void)
{
    static const SDL_version version = { 1, 2, SDL12_COMPAT_VERSION };
    return &version;
}

static int
GetVideoDisplay()
{
    // !!! FIXME: cache this value during SDL_Init() so it doesn't change.
    const char *variable = SDL_getenv("SDL_VIDEO_FULLSCREEN_DISPLAY");
    if ( !variable ) {
        variable = SDL_getenv("SDL_VIDEO_FULLSCREEN_HEAD");
    }
    if ( variable ) {
        return SDL20_atoi(variable);
    } else {
        return 0;
    }
}

DECLSPEC int SDLCALL
SDL_InitSubSystem(Uint32 sdl12flags)
{
    Uint32 sdl20flags = 0;
    int rc;

    if (!LoadSDL20())
        return -1;

    #define SETFLAG(flag) if (sdl12flags & SDL12_INIT_##flag) sdl20flags |= SDL_INIT_##flag
    SETFLAG(TIMER);
    SETFLAG(AUDIO);
    SETFLAG(VIDEO);
    SETFLAG(JOYSTICK);
    SETFLAG(NOPARACHUTE);
    #undef SETFLAG

    // There's no CDROM in 2.0, but we'll just pretend it succeeded.
    if (sdl12flags & SDL12_INIT_CDROM)
        CDRomInit = 1;

    // !!! FIXME: do something about SDL12_INIT_EVENTTHREAD

    rc = SDL20_Init(sdl20flags);
    if ((rc == 0) && (sdl20flags & SDL_INIT_VIDEO))
    {
        int i;
        for (i = 0; i < SDL12_MAXEVENTS-1; i++)
            EventQueuePool[i].next = &EventQueuePool[i+1];
        EventQueuePool[SDL12_MAXEVENTS-1].next = NULL;
        EventQueueHead = EventQueueTail = NULL;
        EventQueueAvailable = EventQueuePool;
        SDL_memset(EventStates, SDL_ENABLE, sizeof (EventStates)); /* on by default */
        EventStates[SDL12_SYSWMEVENT] = SDL_IGNORE;  /* off by default. */
        SDL20_SetEventFilter(EventFilter20to12, NULL);
        VideoDisplayIndex = GetVideoDisplay();
        SwapInterval = 0;
    }

    return rc;
}

DECLSPEC int SDLCALL
SDL_Init(Uint32 sdl12flags)
{
    return SDL_InitSubSubsystem(sdl12flags);   /* there's no difference betwee Init and InitSubSystem in SDL2. */
}

DECLSPEC Uint32 SDLCALL
SDL_WasInit(Uint32 sdl12flags)
{
    // !!! FIXME: this is cut and pasted several places.
    Uint32 sdl20flags = 0;
    Uint32 extraflags = 0;

    #define SETFLAG(flag) if (sdl12flags & SDL12_INIT_##flag) sdl20flags |= SDL_INIT_##flag
    SETFLAG(TIMER);
    SETFLAG(AUDIO);
    SETFLAG(VIDEO);
    SETFLAG(JOYSTICK);
    SETFLAG(NOPARACHUTE);
    #undef SETFLAG

    if ((sdl12flags & SDL12_INIT_CDROM) && (CDRomInit))
        extraflags |= SDL12_INIT_CDROM;

    // !!! FIXME: do something about SDL12_INIT_EVENTTHREAD

    // !!! FIXME: convert back to 1.2
    return SDL20_WasInit(sdl20flags) | extraflags;
}

DECLSPEC void SDLCALL
SDL_QuitSubSystem(Uint32 sdl12flags)
{
    Uint32 sdl20flags = 0;

    #define SETFLAG(flag) if (sdl12flags & SDL12_INIT_##flag) sdl20flags |= SDL_INIT_##flag
    SETFLAG(TIMER);
    SETFLAG(AUDIO);
    SETFLAG(VIDEO);
    SETFLAG(JOYSTICK);
    SETFLAG(NOPARACHUTE);
    // There's no CDROM in 2.0, but we'll just pretend it succeeded.
    #undef SETFLAG

    if (sdl12flags & SDL12_INIT_CDROM)
        CDRomInit = 0;

    // !!! FIXME: reset a bunch of other global variables too.
    if (sdl12flags & SDL12_INIT_VIDEO) {
        EventFilter12 = NULL;
        EventQueueAvailable = EventQueueHead = EventQueueTail = NULL;
        CurrentCursor = NULL;
        SDL20_FreeFormat(VideoInfo.vfmt);
        SDL20_zero(VideoInfo);
    }

    // !!! FIXME: do something about SDL12_INIT_EVENTTHREAD
    SDL20_QuitSubSystem(sdl20flags);

    // !!! FIXME: UnloadSDL20() ?
}

DECLSPEC void SDLCALL
SDL_Quit(void)
{
    // !!! FIXME: reset a bunch of other global variables too.
    EventFilter12 = NULL;
    EventQueueAvailable = EventQueueHead = EventQueueTail = NULL;
    CurrentCursor = NULL;
    SDL20_FreeFormat(VideoInfo.vfmt);
    SDL20_zero(VideoInfo);
    CDRomInit = 0;
    SDL20_Quit();
    UnloadSDL20();
}

DECLSPEC void SDLCALL
SDL_SetError(const char *fmt, ...)
{
    char ch;
    char *str = NULL;
    size_t len = 0;
    va_list ap;
    va_start(ap, fmt);
    len = SDL20_vsnprintf(&ch, 1, fmt, ap);
    va_end(ap);

    str = (char *) SDL20_malloc(len + 1);
    if (!str)
        SDL20_OutOfMemory();
    else
    {
        va_start(ap, fmt);
        SDL20_vsnprintf(str, len + 1, fmt, ap);
        va_end(ap);
        SDL20_SetError("%s", str);
        SDL20_free(str);
    }
}

DECLSPEC const char * SDLCALL
SDL_GetError(void)
{
    if (!Loaded_SDL20)
    {
        static const char noload_errstr[] = "Failed to load SDL 2.0 shared library";
        return noload_errstr;
    }
    return SDL20_GetError();
}


static const char *
GetDriverName(const char *name, char *namebuf, int maxlen)
{
    if (name) {
        if (namebuf) {
            SDL20_strlcpy(namebuf, name, maxlen);
            return namebuf;
        } else {
            return name;
        }
    }
    return NULL;
}

DECLSPEC const char * SDLCALL
SDL_AudioDriverName(char *namebuf, int maxlen)
{
    return GetDriverName(SDL20_GetCurrentAudioDriver(), namebuf, maxlen);
}

DECLSPEC const char * SDLCALL
SDL_VideoDriverName(char *namebuf, int maxlen)
{
    return GetDriverName(SDL20_GetCurrentVideoDriver(), namebuf, maxlen);
}

DECLSPEC int SDLCALL
SDL_PollEvent(SDL12_Event *event12)
{
    EventQueueType *next;

    SDL20_PumpEvents();  /* this will run our filter and build our 1.2 queue. */

    if (EventQueueHead == NULL)
        return 0;  /* no events at the moment. */

    SDL_memcpy(event12, &EventQueueHead->event12, sizeof (SDL12_Event));
    next = EventQueueHead->next;
    EventQueueHead->next = EventQueueAvailable;
    EventQueueAvailable = EventQueueHead;
    EventQueueHead = next;
    return 1;
}

DECLSPEC int SDLCALL
SDL_PushEvent(SDL12_Event *event12)
{
    EventQueueType *item = EventQueueAvailable;
    if (item == NULL)
        return -1;  /* no space available at the moment. */

    EventQueueAvailable = item->next;
    if (EventQueueTail)
        EventQueueTail->next = item;
    else
        EventQueueHead = EventQueueTail = item;
    item->next = NULL;

    SDL_memcpy(&item->event12, event12, sizeof (SDL12_Event));
    return 0;
}

DECLSPEC int SDLCALL
SDL_PeepEvents(SDL12_Event *events12, int numevents, SDL_eventaction action, Uint32 mask)
{
    if (action == SDL_ADDEVENT)
    {
        int i;
        for (i = 0; i < numevents; i++)
        {
            if (SDL_PushEvent(&events12[i]) == -1)
                break;  /* out of space for more events. */
        }
        return i;
    }
    else if ((action == SDL_PEEKEVENT) || (action == SDL_GETEVENT))
    {
        const SDL_bool isGet = (action == SDL_GETEVENT);
        EventQueueType *prev = NULL;
        EventQueueType *item = EventQueueHead;
        EventQueueType *next = NULL;
        int chosen = 0;
        while (chosen < numevents)
        {
            EventQueueType *nextPrev = item;
            if (!item)
                break;  /* no more events at the moment. */

            next = item->next;  /* copy, since we might overwrite item->next */

            if (mask & (1<<item->event12.type))
            {
                SDL_memcpy(&events12[chosen++], &item->event12, sizeof (SDL12_Event));
                if (isGet)  /* remove from list? */
                {
                    if (prev != NULL)
                        prev->next = next;
                    if (item == EventQueueHead)
                        EventQueueHead = next;
                    if (item == EventQueueTail)
                        EventQueueTail = prev;

                    /* put it back in the free pool. */
                    item->next = EventQueueAvailable;
                    EventQueueAvailable = item;
                    nextPrev = prev;  /* previous item doesn't change. */
                }
            }

            item = next;
            prev = nextPrev;
        }
        return chosen;
    }

    return 0;
}

DECLSPEC int SDLCALL
SDL_WaitEvent(SDL12_Event *event12)
{
    /* In 1.2, this only fails (-1) if you haven't SDL_Init()'d. */
    while (!SDL_PollEvent(event12))
        SDL_Delay(10);
    return 1;
}

static SDL_bool
PushEventIfNotFiltered(SDL12_Event *event12)
{
    if (event12->type != SDL12_NOEVENT)
    {
        if (EventStates[event12->type] != SDL_IGNORE)
        {
            if ((!EventFilter12) || (EventFilter12(event12)))
                return (SDL_PushEvent(event12) == 0);
        }
    }
    return SDL_FALSE;
}

DECLSPEC Uint8 SDLCALL
SDL_EventState(Uint8 type, int state)
{
    /* the values of "state" match between 1.2 and 2.0 */
    const Uint8 retval = EventStates[type];
    SDL12_Event e;

    if (state != SDL_QUERY)
        EventStates[type] = state;
    if (state == SDL_IGNORE)  /* drop existing events of this type. */
        while (SDL_PeepEvents(&e, 1, SDL_GETEVENT, (1<<type))) {}

    return retval;
}

DECLSPEC Uint8 SDLCALL
SDL_GetMouseState(int *x, int *y)
{
    const Uint32 state20 = SDL20_GetMouseState(x, y);
    Uint8 retval = (state20 & 0x7);  /* left, right, and middle will match. */

    /* the X[12] buttons are different in 1.2; mousewheel was in the way. */
    if (state20 & SDL_BUTTON(SDL_BUTTON_X1))
        retval |= (1<<5);
    if (state20 & SDL_BUTTON(SDL_BUTTON_X2))
        retval |= (1<<6);

    return retval;
}

static int
EventFilter20to12(void *data, SDL_Event *event20)
{
    const int maxUserEvents12 = SDL12_NUMEVENTS - SDL12_USEREVENT;
    SDL12_Event event12;
    int x, y;

    SDL_assert(data == NULL);  /* currently unused. */

    SDL20_zero(event12);

    switch (event20->type)
    {
        case SDL_QUIT:
            event12.type = SDL12_QUIT;
            break;

        case SDL_WINDOWEVENT:
            switch (event20->window.event)
            {
                case SDL_WINDOWEVENT_CLOSE:
                    event12.type = SDL12_QUIT;
                    break;

                case SDL_WINDOWEVENT_SHOWN:
                case SDL_WINDOWEVENT_EXPOSED:
                    event12.type = SDL12_VIDEOEXPOSE;
                    break;

                case SDL_WINDOWEVENT_RESIZED:
                case SDL_WINDOWEVENT_SIZE_CHANGED:  // !!! FIXME: what's the difference between RESIZED and SIZE_CHANGED?
                    event12.type = SDL12_VIDEORESIZE;
                    event12.resize.w = event20->window.data1;
                    event12.resize.h = event20->window.data2;
                    break;

                case SDL_WINDOWEVENT_MINIMIZED:
                    event12.type = SDL12_ACTIVEEVENT;
                    event12.active.gain = 0;
                    event12.active.state = SDL12_APPACTIVE;
                    break;

                case SDL_WINDOWEVENT_RESTORED:
                    event12.type = SDL12_ACTIVEEVENT;
                    event12.active.gain = 1;
                    event12.active.state = SDL12_APPACTIVE;
                    break;

                case SDL_WINDOWEVENT_ENTER:
                    event12.type = SDL12_ACTIVEEVENT;
                    event12.active.gain = 1;
                    event12.active.state = SDL12_APPMOUSEFOCUS;
                    break;

                case SDL_WINDOWEVENT_LEAVE:
                    event12.type = SDL12_ACTIVEEVENT;
                    event12.active.gain = 0;
                    event12.active.state = SDL12_APPMOUSEFOCUS;
                    break;

                case SDL_WINDOWEVENT_FOCUS_GAINED:
                    event12.type = SDL12_ACTIVEEVENT;
                    event12.active.gain = 1;
                    event12.active.state = SDL12_APPINPUTFOCUS;
                    break;

                case SDL_WINDOWEVENT_FOCUS_LOST:
                    event12.type = SDL12_ACTIVEEVENT;
                    event12.active.gain = 0;
                    event12.active.state = SDL12_APPINPUTFOCUS;
                    break;
            }
            break;

        // !!! FIXME: this is sort of a mess to convert.
        //case SDL_SYSWMEVENT:

        // !!! FIXME: write me
        case SDL_KEYDOWN:
        case SDL_KEYUP:
            return 0;

        // !!! FIXME: write me
        case SDL_TEXTEDITING:
        case SDL_TEXTINPUT:
            return 0;

        case SDL_MOUSEMOTION:
        	event12.type = SDL12_MOUSEMOTION;
            event12.motion.which = (Uint8) event20->motion.which;
            event12.motion.state = event20->motion.state;
            event12.motion.x = (Uint16) event20->motion.x;
            event12.motion.y = (Uint16) event20->motion.y;
            event12.motion.xrel = (Sint16) event20->motion.xrel;
            event12.motion.yrel = (Sint16) event20->motion.yrel;
            break;

        case SDL_MOUSEBUTTONDOWN:
        	event12.type = SDL12_MOUSEBUTTONDOWN;
            event12.button.which = (Uint8) event20->button.which;
            event12.button.button = event20->button.button;
            event12.button.state = event20->button.state;
            event12.button.x = (Uint16) event20->button.x;
            event12.button.y = (Uint16) event20->button.y;
            break;

        case SDL_MOUSEBUTTONUP:
        	event12.type = SDL12_MOUSEBUTTONUP;
            event12.button.which = (Uint8) event20->button.which;
            event12.button.button = event20->button.button;
            event12.button.state = event20->button.state;
            event12.button.x = (Uint16) event20->button.x;
            event12.button.y = (Uint16) event20->button.y;
            break;

        case SDL_MOUSEWHEEL:
            if (event20->wheel.y == 0)
                break;  /* don't support horizontal wheels in 1.2. */

            event12.type = SDL12_MOUSEBUTTONDOWN;
            event12.button.which = (Uint8) event20->wheel.which;
            event12.button.button = (event20->wheel.y > 0) ? 4 : 5;  /* wheelup is 4, down is 5. */
            event12.button.state = SDL_GetMouseState(&x, &y);
            event12.button.x = (Uint16) x;
            event12.button.y = (Uint16) y;
            PushEventIfNotFiltered(&event12);

            event12.type = SDL12_MOUSEBUTTONUP;  /* immediately release mouse "button" at the end of this switch. */
            break;

        case SDL_JOYAXISMOTION:
            event12.type = SDL12_JOYAXISMOTION;
            event12.jaxis.which = (Uint8) event20->jaxis.which;
            event12.jaxis.axis = event20->jaxis.axis;
            event12.jaxis.value = event20->jaxis.value;
            break;

        case SDL_JOYBALLMOTION:
            event12.type = SDL12_JOYBALLMOTION;
            event12.jball.which = (Uint8) event20->jball.which;
            event12.jball.ball = event20->jball.ball;
            event12.jball.xrel = event20->jball.xrel;
            event12.jball.yrel = event20->jball.yrel;
            break;

        case SDL_JOYHATMOTION:
            event12.type = SDL12_JOYHATMOTION;
            event12.jhat.which = (Uint8) event20->jhat.which;
            event12.jhat.hat = event20->jhat.hat;
            event12.jhat.value = event20->jhat.value;
            break;

        case SDL_JOYBUTTONDOWN:
            event12.type = SDL12_JOYBUTTONDOWN;
            event12.jbutton.which = (Uint8) event20->jbutton.which;
            event12.jbutton.button = event20->jbutton.button;
            event12.jbutton.state = event20->jbutton.state;
            break;

        case SDL_JOYBUTTONUP:
            event12.type = SDL12_JOYBUTTONUP;
            event12.jbutton.which = (Uint8) event20->jbutton.which;
            event12.jbutton.button = event20->jbutton.button;
            event12.jbutton.state = event20->jbutton.state;
            break;

        //case SDL_JOYDEVICEADDED:
        //case SDL_JOYDEVICEREMOVED:
	    //case SDL_CONTROLLERAXISMOTION:
	    //case SDL_CONTROLLERBUTTONDOWN:
	    //case SDL_CONTROLLERBUTTONUP:
	    //case SDL_CONTROLLERDEVICEADDED:
	    //case SDL_CONTROLLERDEVICEREMOVED:
	    //case SDL_CONTROLLERDEVICEREMAPPED:
        //case SDL_FINGERDOWN:
        //case SDL_FINGERUP:
        //case SDL_FINGERMOTION:
        //case SDL_DOLLARGESTURE:
        //case SDL_DOLLARRECORD:
        //case SDL_MULTIGESTURE:
        //case SDL_CLIPBOARDUPDATE:
        //case SDL_DROPFILE:

        default:
            return 0;  /* drop everything else. */
    }

    PushEventIfNotFiltered(&event12);

    return 0;  /* always drop it from the 2.0 event queue. */
}

DECLSPEC void SDLCALL
SDL_SetEventFilter(SDL12_EventFilter filter12)
{
    /* We always have a filter installed, but will call the app's too. */
    EventFilter12 = filter12;
}

DECLSPEC SDL12_EventFilter SDLCALL
SDL_GetEventFilter(void)
{
    return EventFilter12;
}


static SDL12_Surface *
Surface20to12(SDL_Surface *surface20)
{
    SDL12_Surface *surface12 = NULL;
    SDL12_Palette *palette12 = NULL;
    SDL12_PixelFormat *format12 = NULL;
    Uint32 flags = 0;

    if (!surface20)
        return NULL;

    surface12 = (SDL12_Surface *) SDL20_malloc(sizeof (SDL12_Surface));
    if (!surface12)
        goto failed;

    palette12 = (SDL12_Palette *) SDL20_malloc(sizeof (SDL12_Palette));
    if (!palette12)
        goto failed;

    format12 = (SDL12_PixelFormat *) SDL20_malloc(sizeof (SDL12_PixelFormat));
    if (!format12)
        goto failed;

    SDL20_zerop(palette12);
    palette12->ncolors = surface20->format->palette->ncolors;
    palette12->colors = surface20->format->palette->colors;

    SDL20_zerop(format12);
    format12->palette = palette12;
    format12->BitsPerPixel = surface20->format->BitsPerPixel;
    format12->BytesPerPixel = surface20->format->BytesPerPixel;
    format12->Rloss = surface20->format->Rloss;
    format12->Gloss = surface20->format->Gloss;
    format12->Bloss = surface20->format->Bloss;
    format12->Aloss = surface20->format->Aloss;
    format12->Rshift = surface20->format->Rshift;
    format12->Gshift = surface20->format->Gshift;
    format12->Bshift = surface20->format->Bshift;
    format12->Ashift = surface20->format->Ashift;
    format12->Rmask = surface20->format->Rmask;
    format12->Gmask = surface20->format->Gmask;
    format12->Bmask = surface20->format->Bmask;
    format12->Amask = surface20->format->Amask;
    /* !!! FIXME: format12->colorkey; */
    /* !!! FIXME: format12->alpha; */

    SDL20_zerop(surface12);
    flags = surface20->flags;
    #define MAPSURFACEFLAGS(fl) { if (surface20->flags & SDL_##fl) { surface12->flags |= SDL12_##fl; flags &= ~SDL_##fl; } }
    MAPSURFACEFLAGS(PREALLOC);
    MAPSURFACEFLAGS(RLEACCEL);
    /*MAPSURFACEFLAGS(DONTFREE);*/
    #undef MAPSURFACEFLAGS
    SDL_assert(flags == 0);  /* non-zero if there's a flag we didn't map. */

    surface12->format = format12;
    surface12->w = surface20->w;
    surface12->h = surface20->h;
    surface12->pitch = (Uint16) surface20->pitch;  /* !!! FIXME: make sure this fits in a Uint16 */
    surface12->pixels = surface20->pixels;
    surface12->offset = 0;
    surface12->surface20 = surface20;
    SDL20_memcpy(&surface12->clip_rect, &surface20->clip_rect, sizeof (SDL_Rect));
    surface12->refcount = surface20->refcount;

    return surface12;

failed:
    SDL20_free(surface12);
    SDL20_free(palette12);
    SDL20_free(format12);
    return NULL;
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_CreateRGBSurface(Uint32 sdl12flags, int width, int height, int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)
{
    SDL_Surface *surface20 = SDL20_CreateRGBSurface(0, width, height, depth, Rmask, Gmask, Bmask, Amask);
    SDL12_Surface *surface12 = Surface20to12(surface20);
    if (!surface12) {
        SDL20_FreeSurface(surface20);
        return NULL;
    }

    SDL_assert(surface12->flags == 0);  // shouldn't have prealloc, rleaccel, or dontfree.
    return surface12;
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_CreateRGBSurfaceFrom(void *pixels, int width, int height, int depth, int pitch, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)
{
    SDL_Surface *surface20 = SDL20_CreateRGBSurfaceFrom(pixels, width, height, depth, pitch, Rmask, Gmask, Bmask, Amask);
    SDL12_Surface *surface12 = Surface20to12(surface20);
    if (!surface12) {
        SDL20_FreeSurface(surface20);
        return NULL;
    }

    SDL_assert(surface12->flags == SDL12_PREALLOC);  // should _only_ have prealloc.
    return surface12;
}

DECLSPEC void SDLCALL
SDL_FreeSurface(SDL12_Surface *surface12)
{
    if (surface12) {
        SDL20_FreeSurface(surface12->surface20);
        if (surface12->format) {
            SDL20_free(surface12->format->palette);
            SDL20_free(surface12->format);
        }
        SDL20_free(surface12);
    }
}

DECLSPEC void SDLCALL
SDL_GetClipRect(SDL12_Surface *surface12, SDL_Rect *rect)
{
    if (surface12 && rect)
	    SDL_memcpy(rect, &surface12->clip_rect, sizeof (SDL_Rect));
}

DECLSPEC SDL_bool SDLCALL
SDL_SetClipRect(SDL12_Surface *surface12, const SDL_Rect *rect)
{
    SDL_bool retval = SDL_FALSE;
    if (surface12)
    {
        retval = SDL20_SetClipRect(surface12->surface20, rect);
        SDL20_GetClipRect(surface12->surface20, &surface12->clip_rect);
    }
    return retval;
}

DECLSPEC int SDLCALL
SDL_FillRect(SDL12_Surface *dst, SDL_Rect *dstrect, Uint32 color)
{
    const SDL_Rect orig_dstrect = *dstrect;
    const int retval = SDL20_FillRect(dst->surface20, &orig_dstrect, color);
    if (retval != -1)
    {
        if (dstrect)  /* 1.2 stores the clip intersection in dstrect */
            SDL20_IntersectRect(&orig_dstrect, &dst->clip_rect, dstrect);
    }
    return retval;
}


static SDL_PixelFormat *
PixelFormat12to20(SDL_PixelFormat *format20, SDL_Palette *palette20, const SDL12_PixelFormat *format12)
{
    palette20->ncolors = format12->palette->ncolors;
    palette20->colors = format12->palette->colors;
    palette20->version = 1;
    palette20->refcount = 1;
    format20->format = SDL20_MasksToPixelFormatEnum(format12->BitsPerPixel, format12->Rmask, format12->Gmask, format12->Bmask, format12->Amask);
    format20->palette = palette20;
    format20->BitsPerPixel = format12->BitsPerPixel;
    format20->BytesPerPixel = format12->BytesPerPixel;
    format20->Rmask = format12->Rmask;
    format20->Gmask = format12->Gmask;
    format20->Bmask = format12->Bmask;
    format20->Amask = format12->Amask;
    format20->Rloss = format12->Rloss;
    format20->Gloss = format12->Gloss;
    format20->Bloss = format12->Bloss;
    format20->Aloss = format12->Aloss;
    format20->Rshift = format12->Rshift;
    format20->Gshift = format12->Gshift;
    format20->Bshift = format12->Bshift;
    format20->Ashift = format12->Ashift;
    format20->refcount = 1;
    format20->next = NULL;
    return format20;
}

DECLSPEC Uint32 SDLCALL
SDL_MapRGB(const SDL12_PixelFormat *format12, Uint8 r, Uint8 g, Uint8 b)
{
    /* This is probably way slower than apps expect. */
    SDL_PixelFormat format20;
    SDL_Palette palette20;
    return SDL20_MapRGB(PixelFormat12to20(&format20, &palette20, format12), r, g, b);
}

DECLSPEC Uint32 SDLCALL
SDL_MapRGBA(const SDL12_PixelFormat *format12, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
{
    /* This is probably way slower than apps expect. */
    SDL_PixelFormat format20;
    SDL_Palette palette20;
    return SDL20_MapRGBA(PixelFormat12to20(&format20, &palette20, format12), r, g, b, a);
}

DECLSPEC void SDLCALL
SDL_GetRGB(Uint32 pixel, const SDL12_PixelFormat *format12, Uint8 *r, Uint8 *g, Uint8 *b)
{
    /* This is probably way slower than apps expect. */
    SDL_PixelFormat format20;
    SDL_Palette palette20;
    return SDL20_GetRGB(pixel, PixelFormat12to20(&format20, &palette20, format12), r, g, b);
}

DECLSPEC void SDLCALL
SDL_GetRGBA(Uint32 pixel, const SDL12_PixelFormat *format12, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a)
{
    /* This is probably way slower than apps expect. */
    SDL_PixelFormat format20;
    SDL_Palette palette20;
    return SDL20_GetRGBA(pixel, PixelFormat12to20(&format20, &palette20, format12), r, g, b, a);
}

DECLSPEC const SDL12_VideoInfo * SDLCALL
SDL_GetVideoInfo(void)
{
    SDL_DisplayMode mode;

    if (!VideoInfo.vfmt && SDL20_GetDesktopDisplayMode(VideoDisplayIndex, &mode) == 0) {
        VideoInfo.vfmt = SDL20_AllocFormat(mode.format);
        VideoInfo.current_w = mode.w;
        VideoInfo.current_h = mode.h;
        // !!! FIXME
        //VideoInfo.wm_available = 1;
        //VideoInfo.video_mem = 1024 * 256;
    }
    return &VideoInfo;
}

DECLSPEC int SDLCALL
SDL_VideoModeOK(int width, int height, int bpp, Uint32 sdl12flags)
{
    int i, nummodes, actual_bpp = 0;

    if (!SDL20_WasInit(SDL_INIT_VIDEO)) {
        return 0;
    }

    if (!(sdl12flags & SDL12_FULLSCREEN)) {
        SDL_DisplayMode mode;
        SDL20_GetDesktopDisplayMode(VideoDisplayIndex, &mode);
        return SDL_BITSPERPIXEL(mode.format);
    }

    nummodes = SDL20_GetNumDisplayModes(VideoDisplayIndex);
    for (i = 0; i < nummodes; ++i) {
        SDL_DisplayMode mode;
        SDL20_GetDisplayMode(VideoDisplayIndex, i, &mode);
        if (!mode.w || !mode.h || (width == mode.w && height == mode.h)) {
            if (!mode.format) {
                return bpp;
            }
            if (SDL_BITSPERPIXEL(mode.format) >= (Uint32) bpp) {
                actual_bpp = SDL_BITSPERPIXEL(mode.format);
            }
        }
    }
    return actual_bpp;
}

#if SANITY_CHECK_THIS_CODE
DECLSPEC SDL_Rect ** SDLCALL
SDL_ListModes(const SDL12_PixelFormat *format, Uint32 flags)
{
    int i, nmodes;
    SDL_Rect **modes;

    if (!SDL20_WasInit(SDL_INIT_VIDEO)) {
        return NULL;
    }

    if (!(flags & SDL12_FULLSCREEN)) {
        return (SDL_Rect **) (-1);
    }

    if (!format) {
        format = VideoInfo.vfmt;
    }

    /* !!! FIXME: Memory leak */
    nmodes = 0;
    modes = NULL;
    for (i = 0; i < SDL20_GetNumDisplayModes(VideoDisplayIndex); ++i) {
        SDL_DisplayMode mode;
        int bpp;

        SDL20_GetDisplayMode(VideoDisplayIndex, i, &mode);
        if (!mode.w || !mode.h) {
            return (SDL_Rect **) (-1);
        }
        
        /* Copied from src/video/SDL_pixels.c:SDL_PixelFormatEnumToMasks */
        if (SDL_BYTESPERPIXEL(mode.format) <= 2) {
            bpp = SDL_BITSPERPIXEL(mode.format);
        } else {
            bpp = SDL_BYTESPERPIXEL(mode.format) * 8;
        }

        if (bpp != format->BitsPerPixel) {
            continue;
        }
        if (nmodes > 0 && modes[nmodes - 1]->w == mode.w
            && modes[nmodes - 1]->h == mode.h) {
            continue;
        }

        modes = SDL20_realloc(modes, (nmodes + 2) * sizeof(*modes));
        if (!modes) {
            return NULL;
        }
        modes[nmodes] = (SDL_Rect *) SDL20_malloc(sizeof(SDL_Rect));
        if (!modes[nmodes]) {
            return NULL;
        }
        modes[nmodes]->x = 0;
        modes[nmodes]->y = 0;
        modes[nmodes]->w = mode.w;
        modes[nmodes]->h = mode.h;
        ++nmodes;
    }
    if (modes) {
        modes[nmodes] = NULL;
    }
    return modes;
}
#endif

DECLSPEC void SDLCALL
SDL_FreeCursor(SDL12_Cursor *cursor12)
{
    if (cursor12)
    {
        if (cursor12->wm_cursor)
            SDL20_FreeCursor(cursor12->wm_cursor);
        SDL20_free(cursor12->data);
        SDL20_free(cursor12->mask);
        SDL20_free(cursor12);
    }
}

DECLSPEC SDL12_Cursor * SDLCALL
SDL_CreateCursor(Uint8 *data, Uint8 *mask, int w, int h, int hot_x, int hot_y)
{
    const size_t datasize = h * (w / 8);
    SDL_Cursor *cursor20 = NULL;
    SDL12_Cursor *retval = NULL;

    retval = (SDL12_Cursor *) SDL20_malloc(sizeof (SDL12_Cursor));
    if (!retval)
        goto outofmem;

    SDL20_zerop(retval);

    retval->data = (Uint8 *) SDL20_malloc(datasize);
    if (!retval->data)
        goto outofmem;

    retval->mask = (Uint8 *) SDL20_malloc(datasize);
    if (!retval->mask)
        goto outofmem;

    cursor20 = SDL20_CreateCursor(data, mask, w, h, hot_x, hot_y);
    if (!cursor20)
        goto failed;

    retval->area.w = w;
    retval->area.h = h;
    retval->hot_x = hot_x;
    retval->hot_y = hot_y;
    retval->wm_cursor = cursor20;
    /* we always leave retval->save as null pointers. */

    SDL20_memcpy(retval->data, data, datasize);
    SDL20_memcpy(retval->mask, mask, datasize);

    return retval;

outofmem:
    SDL20_OutOfMemory();

failed:
    SDL_FreeCursor(retval);
    return NULL;
}

DECLSPEC void SDLCALL
SDL_SetCursor(SDL12_Cursor *cursor)
{
    CurrentCursor = cursor;
    SDL20_SetCursor(cursor ? cursor->wm_cursor : NULL);
}

DECLSPEC SDL12_Cursor * SDLCALL
SDL_GetCursor(void)
{
    return CurrentCursor;
}

static void
GetEnvironmentWindowPosition(int w, int h, int *x, int *y)
{
    int display = VideoDisplayIndex;
    const char *window = SDL_getenv("SDL_VIDEO_WINDOW_POS");
    const char *center = SDL_getenv("SDL_VIDEO_CENTERED");
    if (window) {
        if (SDL_sscanf(window, "%d,%d", x, y) == 2) {
            return;
        }
        if (SDL_strcmp(window, "center") == 0) {
            center = window;
        }
    }
    if (center) {
        *x = SDL_WINDOWPOS_CENTERED_DISPLAY(display);
        *y = SDL_WINDOWPOS_CENTERED_DISPLAY(display);
    }
}

#if SANITY_CHECK_THIS_CODE
static void
ClearVideoSurface()
{
    if (ShadowSurface) {
        SDL20_FillRect(ShadowSurface, NULL,
            SDL20_MapRGB(ShadowSurface->format, 0, 0, 0));
    }
    SDL20_FillRect(WindowSurface, NULL, 0);
    SDL20_UpdateWindowSurface(VideoWindow20);
}
#endif

static void
SetupScreenSaver(int flags12)
{
    const char *env;
    SDL_bool allow_screensaver;

    /* Allow environment override of screensaver disable */
    env = SDL_getenv("SDL_VIDEO_ALLOW_SCREENSAVER");
    if (env) {
        allow_screensaver = SDL20_atoi(env) ? SDL_TRUE : SDL_FALSE;
    } else if (flags12 & SDL12_FULLSCREEN) {
        allow_screensaver = SDL_FALSE;
    } else {
        allow_screensaver = SDL_TRUE;
    }
    if (allow_screensaver) {
        SDL20_EnableScreenSaver();
    } else {
        SDL20_DisableScreenSaver();
    }
}

#if SANITY_CHECK_THIS_CODE
static int
ResizeVideoMode(int width, int height, int bpp, Uint32 flags12)
{
    int w, h;

    /* We can't resize something we don't have... */
    if (!VideoSurface) {
        return -1;
    }

    /* We probably have to recreate the window in fullscreen mode */
    if (flags12 & SDL12_FULLSCREEN) {
        return -1;
    }

    /* I don't think there's any change we can gracefully make in flags */
    if (flags12 != VideoFlags) {
        return -1;
    }
    if (bpp != VideoSurface->format->BitsPerPixel) {
        return -1;
    }

    /* Resize the window */
    SDL20_GetWindowSize(VideoWindow20, &w, &h);
    if (w != width || h != height) {
        SDL20_SetWindowSize(VideoWindow20, width, height);
    }

    /* If we're in OpenGL mode, just resize the stub surface and we're done! */
    if (flags12 & SDL12_OPENGL) {
        VideoSurface->w = width;
        VideoSurface->h = height;
        return 0;
    }

    WindowSurface = SDL20_GetWindowSurface(VideoWindow20);
    if (!WindowSurface) {
        return -1;
    }
    if (VideoSurface->format != WindowSurface->format) {
        return -1;
    }
    VideoSurface->w = width;
    VideoSurface->h = height;
    VideoSurface->pixels = WindowSurface->pixels;
    VideoSurface->pitch = WindowSurface->pitch;
    SDL20_SetClipRect(VideoSurface, NULL);

    if (ShadowSurface) {
        ShadowSurface->w = width;
        ShadowSurface->h = height;
        ShadowSurface->pitch = SDL20_CalculatePitch(ShadowSurface);
        ShadowSurface->pixels =
            SDL20_realloc(ShadowSurface->pixels,
                        ShadowSurface->h * ShadowSurface->pitch);
        SDL20_SetClipRect(ShadowSurface, NULL);
        SDL20_InvalidateMap(ShadowSurface->map);
    } else {
        PublicSurface = VideoSurface;
    }

    ClearVideoSurface();

    return 0;
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_SetVideoMode(int width, int height, int bpp, Uint32 flags12)
{
    SDL_DisplayMode desktop_mode;
    int display = VideoDisplayIndex;
    int window_x = SDL_WINDOWPOS_UNDEFINED_DISPLAY(display);
    int window_y = SDL_WINDOWPOS_UNDEFINED_DISPLAY(display);
    int window_w;
    int window_h;
    Uint32 window_flags20;
    Uint32 surface_flags12;

    if (!SDL20_WasInit(SDL_INIT_VIDEO)) {
        if (SDL_Init(SDL12_INIT_VIDEO | SDL12_INIT_NOPARACHUTE) < 0) {
            return NULL;
        }
    }

    SDL20_GetDesktopDisplayMode(display, &desktop_mode);

    if (width == 0) {
        width = desktop_mode.w;
    }
    if (height == 0) {
        height = desktop_mode.h;
    }
    if (bpp == 0) {
        bpp = SDL_BITSPERPIXEL(desktop_mode.format);
    }

    /* See if we can simply resize the existing window and surface */
    if (ResizeVideoMode(width, height, bpp, flags12) == 0) {
        return PublicSurface;
    }

    /* Destroy existing window */
    PublicSurface = NULL;
    if (ShadowSurface) {
        ShadowSurface->flags &= ~SDL_DONTFREE;
        SDL20_FreeSurface(ShadowSurface);
        ShadowSurface = NULL;
    }
    if (VideoSurface) {
        VideoSurface->flags &= ~SDL_DONTFREE;
        SDL20_FreeSurface(VideoSurface);
        VideoSurface = NULL;
    }
    if (VideoContext) {
        /* SDL_GL_MakeCurrent(0, NULL); *//* Doesn't do anything */
        SDL20_GL_DeleteContext(VideoContext);
        VideoContext = NULL;
    }
    if (VideoWindow20) {
        SDL20_GetWindowPosition(VideoWindow20, &window_x, &window_y);
        SDL20_DestroyWindow(VideoWindow20);
    }

    /* Create a new window */
    window_flags20 = SDL_WINDOW_SHOWN;
    if (flags12 & SDL12_FULLSCREEN) {
        window_flags20 |= SDL_WINDOW_FULLSCREEN;
    }
    if (flags12 & SDL12_OPENGL) {
        window_flags20 |= SDL_WINDOW_OPENGL;
    }
    if (flags12 & SDL12_RESIZABLE) {
        window_flags20 |= SDL_WINDOW_RESIZABLE;
    }
    if (flags12 & SDL12_NOFRAME) {
        window_flags20 |= SDL_WINDOW_BORDERLESS;
    }
    GetEnvironmentWindowPosition(width, height, &window_x, &window_y);
    VideoWindow20 =
        SDL20_CreateWindow(WindowTitle, window_x, window_y, width, height,
                         window_flags20);
    if (!VideoWindow20) {
        return NULL;
    }
    SDL20_SetWindowIcon(VideoWindow20, VideoIcon);

    SetupScreenSaver(flags12);

    window_flags20 = SDL20_GetWindowFlags(VideoWindow20);
    surface_flags12 = 0;
    if (window_flags20 & SDL_WINDOW_FULLSCREEN) {
        surface_flags12 |= SDL_FULLSCREEN;
    }
    if ((window_flags & SDL_WINDOW_OPENGL) && (flags12 & SDL_OPENGL)) {
        surface_flags12 |= SDL_OPENGL;
    }
    if (window_flags & SDL_WINDOW_RESIZABLE) {
        surface_flags12 |= SDL_RESIZABLE;
    }
    if (window_flags & SDL_WINDOW_BORDERLESS) {
        surface_flags12 |= SDL_NOFRAME;
    }

    VideoFlags = flags12;

    /* If we're in OpenGL mode, just create a stub surface and we're done! */
    if (flags12 & SDL_OPENGL) {

        VideoContext = SDL_GL_CreateContext(VideoWindow20);
        if (!VideoContext) {
            return NULL;
        }
        if (SDL_GL_MakeCurrent(VideoWindow20, VideoContext) < 0) {
            return NULL;
        }

        SDL20_GL_SetSwapInterval(SwapInterval);  /* don't care if this fails. */

        VideoSurface =
            SDL_CreateRGBSurfaceFrom(NULL, width, height, bpp, 0, 0, 0, 0, 0);
        if (!VideoSurface) {
            return NULL;
        }
        VideoSurface->flags |= surface_flags12;
        PublicSurface = VideoSurface;
        return PublicSurface;
    }

    /* Create the screen surface */
    WindowSurface = SDL_GetWindowSurface(VideoWindow20);
    if (!WindowSurface) {
        return NULL;
    }

    /* Center the public surface in the window surface */
    SDL_GetWindowSize(VideoWindow20, &window_w, &window_h);
    VideoViewport.x = (window_w - width)/2;
    VideoViewport.y = (window_h - height)/2;
    VideoViewport.w = width;
    VideoViewport.h = height;

    VideoSurface = SDL_CreateRGBSurfaceFrom(NULL, 0, 0, 32, 0, 0, 0, 0, 0);
    VideoSurface->flags |= surface_flags12;
    VideoSurface->flags |= SDL12_DONTFREE;
    SDL_FreeFormat(VideoSurface->format);
    VideoSurface->format = WindowSurface->format;
    VideoSurface->format->refcount++;
    VideoSurface->w = width;
    VideoSurface->h = height;
    VideoSurface->pitch = WindowSurface->pitch;
    VideoSurface->pixels = (void *)((Uint8 *)WindowSurface->pixels +
        VideoViewport.y * VideoSurface->pitch +
        VideoViewport.x  * VideoSurface->format->BytesPerPixel);
    SDL_SetClipRect(VideoSurface, NULL);

    /* Create a shadow surface if necessary */
    if ((bpp != VideoSurface->format->BitsPerPixel)
        && !(flags12 & SDL12_ANYFORMAT)) {
        ShadowSurface =
            SDL_CreateRGBSurface(0, width, height, bpp, 0, 0, 0, 0);
        if (!ShadowSurface) {
            return NULL;
        }
        ShadowSurface->flags |= surface_flags12;
        ShadowSurface->flags |= SDL12_DONTFREE;

        /* 8-bit ShadowSurface surfaces report that they have exclusive palette */
        if (ShadowSurface->format->palette) {
            ShadowSurface->flags |= SDL12_HWPALETTE;
            SDL_DitherColors(ShadowSurface->format->palette->colors,
                             ShadowSurface->format->BitsPerPixel);
        }
        SDL_FillRect(ShadowSurface, NULL,
            SDL_MapRGB(ShadowSurface->format, 0, 0, 0));
    }
    PublicSurface =
        (ShadowSurface ? ShadowSurface : VideoSurface);

    ClearVideoSurface();

    /* We're finally done! */
    return PublicSurface;
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_GetVideoSurface(void)
{
    return PublicSurface;
}

DECLSPEC int SDLCALL
SDL_SetAlpha(SDL12_Surface * surface, Uint32 flag, Uint8 value)
{
    if (flag & SDL_SRCALPHA) {
        /* According to the docs, value is ignored for alpha surfaces */
        if (surface->format->Amask) {
            value = 0xFF;
        }
        SDL_SetSurfaceAlphaMod(surface, value);
        SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_BLEND);
    } else {
        SDL_SetSurfaceAlphaMod(surface, 0xFF);
        SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_NONE);
    }
    SDL_SetSurfaceRLE(surface, (flag & SDL_RLEACCEL));

    return 0;
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_DisplayFormat(SDL12_Surface *surface12)
{
    SDL12_PixelFormat *format;

    if (!PublicSurface) {
        SDL20_SetError("No video mode has been set");
        return NULL;
    }
    format = PublicSurface->format;

    /* Set the flags appropriate for copying to display surface */
    return SDL_ConvertSurface(surface, format, SDL12_RLEACCEL);
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_DisplayFormatAlpha(SDL12_Surface *surface)
{
    SDL_PixelFormat *vf;
    SDL_PixelFormat *format;
    SDL_Surface *converted;
    /* default to ARGB8888 */
    Uint32 amask = 0xff000000;
    Uint32 rmask = 0x00ff0000;
    Uint32 gmask = 0x0000ff00;
    Uint32 bmask = 0x000000ff;

    if (!PublicSurface) {
        SDL20_SetError("No video mode has been set");
        return NULL;
    }
    vf = PublicSurface->format;

    switch (vf->BytesPerPixel) {
    case 2:
        /* For XGY5[56]5, use, AXGY8888, where {X, Y} = {R, B}.
           For anything else (like ARGB4444) it doesn't matter
           since we have no special code for it anyway */
        if ((vf->Rmask == 0x1f) &&
            (vf->Bmask == 0xf800 || vf->Bmask == 0x7c00)) {
            rmask = 0xff;
            bmask = 0xff0000;
        }
        break;

    case 3:
    case 4:
        /* Keep the video format, as long as the high 8 bits are
           unused or alpha */
        if ((vf->Rmask == 0xff) && (vf->Bmask == 0xff0000)) {
            rmask = 0xff;
            bmask = 0xff0000;
        }
        break;

    default:
        /* We have no other optimised formats right now. When/if a new
           optimised alpha format is written, add the converter here */
        break;
    }
    format = SDL_AllocFormat(SDL_MasksToPixelFormatEnum(32, rmask,
                                                            gmask,
                                                            bmask,
                                                            amask));
    if (!format) {
        return NULL;
    }
    converted = SDL_ConvertSurface(surface, format, SDL_RLEACCEL);
    SDL_FreeFormat(format);
    return converted;
}

DECLSPEC void SDLCALL
SDL_UpdateRects(SDL_Surface * screen, int numrects, SDL_Rect * rects)
{
    int i;

    if (screen == ShadowSurface) {
        for (i = 0; i < numrects; ++i) {
            SDL_BlitSurface(ShadowSurface, &rects[i], VideoSurface,
                            &rects[i]);
        }

        /* Fall through to video surface update */
        screen = VideoSurface;
    }
    if (screen == VideoSurface) {
        if (VideoViewport.x || VideoViewport.y) {
            SDL_Rect *stackrects = SDL_stack_alloc(SDL_Rect, numrects);
            SDL_Rect *stackrect;
            const SDL_Rect *rect;
            
            /* Offset all the rectangles before updating */
            for (i = 0; i < numrects; ++i) {
                rect = &rects[i];
                stackrect = &stackrects[i];
                stackrect->x = VideoViewport.x + rect->x;
                stackrect->y = VideoViewport.y + rect->y;
                stackrect->w = rect->w;
                stackrect->h = rect->h;
            }
            SDL_UpdateWindowSurfaceRects(VideoWindow20, stackrects, numrects);
            SDL_stack_free(stackrects);
        } else {
            SDL_UpdateWindowSurfaceRects(VideoWindow20, rects, numrects);
        }
    }
}
#endif

DECLSPEC void SDLCALL
SDL_UpdateRect(SDL12_Surface *screen12, Sint32 x, Sint32 y, Uint32 w, Uint32 h)
{
    if (screen12) {
        SDL_Rect rect;
        rect.x = (int) x;
        rect.y = (int) y;
        rect.w = (int) (w ? w : screen12->w);
        rect.h = (int) (h ? h : screen12->h);
        SDL_UpdateRects(screen12, 1, &rect);
    }
}

DECLSPEC int SDLCALL
SDL_Flip(SDL12_Surface *screen12)
{
    SDL_UpdateRect(screen12, 0, 0, 0, 0);
    return 0;
}

DECLSPEC void SDLCALL
SDL_WM_SetCaption(const char *title, const char *icon)
{
    if (WindowTitle) {
        SDL20_free(WindowTitle);
    }
    if (WindowIconTitle) {
        SDL20_free(WindowIconTitle);
    }
    WindowTitle = title ? SDL_strdup(title) : NULL;
    WindowIconTitle = icon ? SDL_strdup(icon) : NULL;
    SDL20_SetWindowTitle(VideoWindow20, WindowTitle);
}

DECLSPEC void SDLCALL
SDL_WM_GetCaption(const char **title, const char **icon)
{
    if (title) {
        *title = WindowTitle;
    }
    if (icon) {
        *icon = WindowIconTitle;
    }
}

#if SANITY_CHECK_THIS_CODE
DECLSPEC void SDLCALL
SDL_WM_SetIcon(SDL_Surface *icon, Uint8 *mask)
{
    // !!! FIXME: free previous icon?
    VideoIcon = icon;
    ++VideoIcon->refcount;
}
#endif

DECLSPEC int SDLCALL
SDL_WM_IconifyWindow(void)
{
    SDL20_MinimizeWindow(VideoWindow20);
    return 0;
}

#if SANITY_CHECK_THIS_CODE
DECLSPEC int SDLCALL
SDL_WM_ToggleFullScreen(SDL_Surface *surface)
{
    int length;
    void *pixels;
    Uint8 *src, *dst;
    int row;
    int window_w;
    int window_h;

    if (!PublicSurface) {
        SDL20_SetError("SDL_SetVideoMode() hasn't been called");
        return 0;
    }

    /* Copy the old bits out */
    length = PublicSurface->w * PublicSurface->format->BytesPerPixel;
    pixels = SDL20_malloc(PublicSurface->h * length);
    if (pixels && PublicSurface->pixels) {
        src = (Uint8*)PublicSurface->pixels;
        dst = (Uint8*)pixels;
        for (row = 0; row < PublicSurface->h; ++row) {
            SDL_memcpy(dst, src, length);
            src += PublicSurface->pitch;
            dst += length;
        }
    }

    /* Do the physical mode switch */
    if (SDL20_GetWindowFlags(VideoWindow20) & SDL_WINDOW_FULLSCREEN) {
        if (SDL20_SetWindowFullscreen(VideoWindow20, 0) < 0) {
            return 0;
        }
        PublicSurface->flags &= ~SDL_FULLSCREEN;
    } else {
        if (SDL20_SetWindowFullscreen(VideoWindow20, 1) < 0) {
            return 0;
        }
        PublicSurface->flags |= SDL_FULLSCREEN;
    }

    /* Recreate the screen surface */
    WindowSurface = SDL20_GetWindowSurface(VideoWindow20);
    if (!WindowSurface) {
        /* We're totally hosed... */
        return 0;
    }

    /* Center the public surface in the window surface */
    SDL_GetWindowSize(VideoWindow20, &window_w, &window_h);
    VideoViewport.x = (window_w - VideoSurface->w)/2;
    VideoViewport.y = (window_h - VideoSurface->h)/2;
    VideoViewport.w = VideoSurface->w;
    VideoViewport.h = VideoSurface->h;

    /* Do some shuffling behind the application's back if format changes */
    if (VideoSurface->format->format != WindowSurface->format->format) {
        if (ShadowSurface) {
            if (ShadowSurface->format->format == WindowSurface->format->format) {
                /* Whee!  We don't need a shadow surface anymore! */
                VideoSurface->flags &= ~SDL_DONTFREE;
                SDL_FreeSurface(VideoSurface);
                SDL20_free(ShadowSurface->pixels);
                VideoSurface = ShadowSurface;
                VideoSurface->flags |= SDL_PREALLOC;
                ShadowSurface = NULL;
            } else {
                /* No problem, just change the video surface format */
                SDL_FreeFormat(VideoSurface->format);
                VideoSurface->format = WindowSurface->format;
                VideoSurface->format->refcount++;
                SDL_InvalidateMap(ShadowSurface->map);
            }
        } else {
            /* We can make the video surface the shadow surface */
            ShadowSurface = VideoSurface;
            ShadowSurface->pitch = SDL_CalculatePitch(ShadowSurface);
            ShadowSurface->pixels = SDL20_malloc(ShadowSurface->h * ShadowSurface->pitch);
            if (!ShadowSurface->pixels) {
                /* Uh oh, we're hosed */
                ShadowSurface = NULL;
                return 0;
            }
            ShadowSurface->flags &= ~SDL_PREALLOC;

            VideoSurface = SDL_CreateRGBSurfaceFrom(NULL, 0, 0, 32, 0, 0, 0, 0, 0);
            VideoSurface->flags = ShadowSurface->flags;
            VideoSurface->flags |= SDL_PREALLOC;
            SDL_FreeFormat(VideoSurface->format);
            VideoSurface->format = WindowSurface->format;
            VideoSurface->format->refcount++;
            VideoSurface->w = ShadowSurface->w;
            VideoSurface->h = ShadowSurface->h;
        }
    }

    /* Update the video surface */
    VideoSurface->pitch = WindowSurface->pitch;
    VideoSurface->pixels = (void *)((Uint8 *)WindowSurface->pixels +
        VideoViewport.y * VideoSurface->pitch +
        VideoViewport.x  * VideoSurface->format->BytesPerPixel);
    SDL_SetClipRect(VideoSurface, NULL);

    /* Copy the old bits back */
    if (pixels) {
        src = (Uint8*)pixels;
        dst = (Uint8*)PublicSurface->pixels;
        for (row = 0; row < PublicSurface->h; ++row) {
            SDL_memcpy(dst, src, length);
            src += length;
            dst += PublicSurface->pitch;
        }
        SDL_Flip(PublicSurface);
        SDL20_free(pixels);
    }

    /* We're done! */
    return 1;
}
#endif

typedef enum
{
    SDL12_GRAB_QUERY = -1,
    SDL12_GRAB_OFF = 0,
    SDL12_GRAB_ON = 1
} SDL12_GrabMode;

DECLSPEC SDL12_GrabMode SDLCALL
SDL_WM_GrabInput(SDL12_GrabMode mode)
{
    if (mode != SDL12_GRAB_QUERY) {
        SDL20_SetWindowGrab(VideoWindow20, (mode == SDL12_GRAB_ON));
    }
    return SDL20_GetWindowGrab(VideoWindow20) ? SDL12_GRAB_ON : SDL12_GRAB_OFF;
}

DECLSPEC void SDLCALL
SDL_WarpMouse(Uint16 x, Uint16 y)
{
    SDL20_WarpMouseInWindow(VideoWindow20, x, y);
}

DECLSPEC Uint8 SDLCALL
SDL_GetAppState(void)
{
    Uint8 state12 = 0;
    Uint32 flags20 = 0;

    flags20 = SDL20_GetWindowFlags(VideoWindow20);
    if ((flags20 & SDL_WINDOW_SHOWN) && !(flags20 & SDL_WINDOW_MINIMIZED)) {
        state12 |= SDL12_APPACTIVE;
    }
    if (flags20 & SDL_WINDOW_INPUT_FOCUS) {
        state12 |= SDL12_APPINPUTFOCUS;
    }
    if (flags20 & SDL_WINDOW_MOUSE_FOCUS) {
        state12 |= SDL12_APPMOUSEFOCUS;
    }
    return state12;
}

#if SANITY_CHECK_THIS_CODE
DECLSPEC int SDLCALL
SDL_SetPalette(SDL12_Surface *surface12, int flags, const SDL_Color *colors,
               int firstcolor, int ncolors)
{
    return SDL_SetColors(surface12, colors, firstcolor, ncolors);
}

DECLSPEC int SDLCALL
SDL_SetColors(SDL12_Surface *surface12, const SDL_Color * colors, int firstcolor,
              int ncolors)
{
    if (SDL20_SetPaletteColors
        (surface->format->palette, colors, firstcolor, ncolors) == 0) {
        return 1;
    } else {
        return 0;
    }
}

DECLSPEC int SDLCALL
SDL_GetWMInfo(SDL_SysWMinfo * info)
{
    return SDL_GetWindowWMInfo(VideoWindow20, info);
}

struct private_yuvhwdata
{
    SDL_SW_YUVTexture *texture;
    SDL_Surface *display;
    Uint32 display_format;
};

DECLSPEC SDL_Overlay * SDLCALL
SDL_CreateYUVOverlay(int w, int h, Uint32 format, SDL12_Surface *display)
{
    SDL_Overlay *overlay;
    Uint32 texture_format;
    SDL_SW_YUVTexture *texture;

    if ((display->flags & SDL_OPENGL) == SDL_OPENGL) {
        SDL20_SetError("YUV overlays are not supported in OpenGL mode");
        return NULL;
    }

    if (display != PublicSurface) {
        SDL20_SetError("YUV display is only supported on the screen surface");
        return NULL;
    }

    switch (format) {
    case SDL_YV12_OVERLAY:
        texture_format = SDL_PIXELFORMAT_YV12;
        break;
    case SDL_IYUV_OVERLAY:
        texture_format = SDL_PIXELFORMAT_IYUV;
        break;
    case SDL_YUY2_OVERLAY:
        texture_format = SDL_PIXELFORMAT_YUY2;
        break;
    case SDL_UYVY_OVERLAY:
        texture_format = SDL_PIXELFORMAT_UYVY;
        break;
    case SDL_YVYU_OVERLAY:
        texture_format = SDL_PIXELFORMAT_YVYU;
        break;
    default:
        SDL20_SetError("Unknown YUV format");
        return NULL;
    }

    overlay = (SDL_Overlay *) SDL20_malloc(sizeof(*overlay));
    if (!overlay) {
        SDL20_OutOfMemory();
        return NULL;
    }
    SDL20_zerop(overlay);

    overlay->hwdata =
        (struct private_yuvhwdata *) SDL20_malloc(sizeof(*overlay->hwdata));
    if (!overlay->hwdata) {
        SDL20_free(overlay);
        SDL20_OutOfMemory();
        return NULL;
    }

    texture = SDL_SW_CreateYUVTexture(texture_format, w, h);
    if (!texture) {
        SDL20_free(overlay->hwdata);
        SDL20_free(overlay);
        return NULL;
    }
    overlay->hwdata->texture = texture;
    overlay->hwdata->display = NULL;
    overlay->hwdata->display_format = SDL_PIXELFORMAT_UNKNOWN;

    overlay->format = format;
    overlay->w = w;
    overlay->h = h;
    if (format == SDL_YV12_OVERLAY || format == SDL_IYUV_OVERLAY) {
        overlay->planes = 3;
    } else {
        overlay->planes = 1;
    }
    overlay->pitches = texture->pitches;
    overlay->pixels = texture->planes;

    return overlay;
}

DECLSPEC int SDLCALL
SDL_LockYUVOverlay(SDL_Overlay * overlay)
{
    SDL_Rect rect;
    void *pixels;
    int pitch;

    if (!overlay) {
        return SDL20_SetError("Passed a NULL overlay");
    }

    rect.x = 0;
    rect.y = 0;
    rect.w = overlay->w;
    rect.h = overlay->h;

    if (SDL_SW_LockYUVTexture(overlay->hwdata->texture, &rect, &pixels, &pitch) < 0) {
        return -1;
    }

    overlay->pixels[0] = (Uint8 *) pixels;
    overlay->pitches[0] = pitch;
    switch (overlay->format) {
    case SDL_YV12_OVERLAY:
    case SDL_IYUV_OVERLAY:
        overlay->pitches[1] = pitch / 2;
        overlay->pitches[2] = pitch / 2;
        overlay->pixels[1] =
            overlay->pixels[0] + overlay->pitches[0] * overlay->h;
        overlay->pixels[2] =
            overlay->pixels[1] + overlay->pitches[1] * overlay->h / 2;
        break;
    case SDL_YUY2_OVERLAY:
    case SDL_UYVY_OVERLAY:
    case SDL_YVYU_OVERLAY:
        break;
    }
    return 0;
}

DECLSPEC void SDLCALL
SDL_UnlockYUVOverlay(SDL_Overlay * overlay)
{
    if (!overlay) {
        return;
    }

    SDL_SW_UnlockYUVTexture(overlay->hwdata->texture);
}

DECLSPEC int SDLCALL
SDL_DisplayYUVOverlay(SDL_Overlay * overlay, SDL_Rect * dstrect)
{
    SDL_Surface *display;
    SDL_Rect src_rect;
    SDL_Rect dst_rect;
    void *pixels;

    if (!overlay || !dstrect) {
        return SDL20_SetError("Passed a NULL overlay or dstrect");
    }

    display = overlay->hwdata->display;
    if (display != VideoSurface) {
        overlay->hwdata->display = display = VideoSurface;
        overlay->hwdata->display_format = SDL_MasksToPixelFormatEnum(
                                                display->format->BitsPerPixel,
                                                display->format->Rmask,
                                                display->format->Gmask,
                                                display->format->Bmask,
                                                display->format->Amask);
    }

    src_rect.x = 0;
    src_rect.y = 0;
    src_rect.w = overlay->w;
    src_rect.h = overlay->h;

    if (!SDL_IntersectRect(&display->clip_rect, dstrect, &dst_rect)) {
        return 0;
    }
     
    pixels = (void *)((Uint8 *)display->pixels +
                        dst_rect.y * display->pitch +
                        dst_rect.x * display->format->BytesPerPixel);

    if (SDL_SW_CopyYUVToRGB(overlay->hwdata->texture, &src_rect,
                            overlay->hwdata->display_format,
                            dst_rect.w, dst_rect.h,
                            pixels, display->pitch) < 0) {
        return -1;
    }
    SDL_UpdateWindowSurface(VideoWindow20);
    return 0;
}

DECLSPEC void SDLCALL
SDL_FreeYUVOverlay(SDL_Overlay * overlay)
{
    if (!overlay) {
        return;
    }
    if (overlay->hwdata) {
        if (overlay->hwdata->texture) {
            SDL_SW_DestroyYUVTexture(overlay->hwdata->texture);
        }
        SDL20_free(overlay->hwdata);
    }
    SDL20_free(overlay);
}
#endif

DECLSPEC int SDLCALL
SDL_GL_SetAttribute(SDL12_GLattr attr, int value)
{
    if (attr >= SDL12_GL_MAX_ATTRIBUTE)
        return SDL20_SetError("Unknown GL attribute");

    /* swap control was moved out of this API, everything else lines up. */
    if (attr == SDL12_GL_SWAP_CONTROL)
    {
        SwapInterval = value;
        return 0;
    }

    return SDL20_GL_SetAttribute((SDL_GLattr) attr, value);
}

DECLSPEC int SDLCALL
SDL_GL_GetAttribute(SDL12_GLattr attr, int* value)
{
    if (attr >= SDL12_GL_MAX_ATTRIBUTE)
        return SDL20_SetError("Unknown GL attribute");

    /* swap control was moved out of this API, everything else lines up. */
    if (attr == SDL12_GL_SWAP_CONTROL)
    {
        *value = SDL20_GL_GetSwapInterval();
        return 0;
    }

    return SDL20_GL_GetAttribute((SDL_GLattr) attr, value);
}


DECLSPEC void SDLCALL
SDL_GL_SwapBuffers(void)
{
    if (VideoWindow20)
        SDL20_GL_SwapWindow(VideoWindow20);
}

DECLSPEC int SDLCALL
SDL_SetGamma(float red, float green, float blue)
{
    Uint16 red_ramp[256];
    Uint16 green_ramp[256];
    Uint16 blue_ramp[256];

    SDL20_CalculateGammaRamp(red, red_ramp);
    if (green == red) {
        SDL20_memcpy(green_ramp, red_ramp, sizeof(red_ramp));
    } else {
        SDL20_CalculateGammaRamp(green, green_ramp);
    }
    if (blue == red) {
        SDL20_memcpy(blue_ramp, red_ramp, sizeof(red_ramp));
    } else if (blue == green) {
        SDL20_memcpy(blue_ramp, green_ramp, sizeof(green_ramp));
    } else {
        SDL20_CalculateGammaRamp(blue, blue_ramp);
    }
    return SDL20_SetWindowGammaRamp(VideoWindow20, red_ramp, green_ramp, blue_ramp);
}

DECLSPEC int SDLCALL
SDL_SetGammaRamp(const Uint16 *red, const Uint16 *green, const Uint16 *blue)
{
    return SDL20_SetWindowGammaRamp(VideoWindow20, red, green, blue);
}

DECLSPEC int SDLCALL
SDL_GetGammaRamp(Uint16 *red, Uint16 *green, Uint16 *blue)
{
    return SDL20_GetWindowGammaRamp(VideoWindow20, red, green, blue);
}

DECLSPEC int SDLCALL
SDL_EnableKeyRepeat(int delay, int interval)
{
    return 0;
}

DECLSPEC void SDLCALL
SDL_GetKeyRepeat(int *delay, int *interval)
{
    if (delay) {
        *delay = SDL12_DEFAULT_REPEAT_DELAY;
    }
    if (interval) {
        *interval = SDL12_DEFAULT_REPEAT_INTERVAL;
    }
}

#if SANITY_CHECK_THIS_CODE
DECLSPEC int SDLCALL
SDL_EnableUNICODE(int enable)
{
    int previous = EnabledUnicode;

    switch (enable) {
    case 1:
        EnabledUnicode = 1;
        SDL20_StartTextInput();
        break;
    case 0:
        EnabledUnicode = 0;
        SDL20_StopTextInput();
        break;
    }
    return previous;
}
#endif

static Uint32
SetTimerOld_Callback(Uint32 interval, void* param)
{
    return ((SDL12_TimerCallback)param)(interval);
}

DECLSPEC int SDLCALL
SDL_SetTimer(Uint32 interval, SDL12_TimerCallback callback)
{
    static SDL_TimerID compat_timer;

    if (compat_timer) {
        SDL20_RemoveTimer(compat_timer);
        compat_timer = 0;
    }

    if (interval && callback) {
        compat_timer = SDL20_AddTimer(interval, SetTimerOld_Callback, callback);
        if (!compat_timer) {
            return -1;
        }
    }
    return 0;
}

DECLSPEC int SDLCALL
SDL_putenv(const char *_var)
{
    char *ptr = NULL;
    char *var = SDL20_strdup(_var);
    if (var == NULL) {
        return -1;  /* we don't set errno. */
    }

    ptr = SDL20_strchr(var, '=');
    if (ptr == NULL) {
        SDL20_free(var);
        return -1;
    }

    *ptr = '\0';  /* split the string into name and value. */
    SDL20_setenv(var, ptr + 1, 1);
    SDL20_free(var);
    return 0;
}


/* CD-ROM support is gone from SDL 2.0, so just have stubs that fail. */

typedef void *SDL12_CD;  /* close enough.  :) */
typedef int SDL12_CDstatus;  /* close enough.  :) */

DECLSPEC int SDLCALL
SDL_CDNumDrives(void)
{
    return 0;  /* !!! FIXME: should return -1 without SDL_INIT_CDROM */
}

DECLSPEC const char *SDLCALL SDL_CDName(int drive) { SDL20_Unsupported(); return NULL; }
DECLSPEC SDL12_CD *SDLCALL SDL_CDOpen(int drive) { SDL20_Unsupported(); return NULL; }
DECLSPEC SDL12_CDstatus SDLCALL SDL_CDStatus(SDL12_CD *cdrom) { return SDL20_Unsupported(); }
DECLSPEC int SDLCALL SDL_CDPlayTracks(SDL12_CD *cdrom, int start_track, int start_frame, int ntracks, int nframes) { return SDL20_Unsupported(); }
DECLSPEC int SDLCALL SDL_CDPlay(SDL12_CD *cdrom, int start, int length) { return SDL20_Unsupported(); }
DECLSPEC int SDLCALL SDL_CDPause(SDL12_CD *cdrom) { return SDL20_Unsupported(); }
DECLSPEC int SDLCALL SDL_CDResume(SDL12_CD *cdrom) { return SDL20_Unsupported(); }
DECLSPEC int SDLCALL SDL_CDStop(SDL12_CD *cdrom) { return SDL20_Unsupported(); }
DECLSPEC int SDLCALL SDL_CDEject(SDL12_CD *cdrom) { return SDL20_Unsupported(); }
DECLSPEC void SDLCALL SDL_CDClose(SDL12_CD *cdrom) {}


#ifdef SDL_PASSED_BEGINTHREAD_ENDTHREAD
DECLSPEC SDL_Thread * SDLCALL
SDL_CreateThread(int (SDLCALL *fn)(void *), void *data, pfnSDL_CurrentBeginThread pfnBeginThread, pfnSDL_CurrentEndThread pfnEndThread)
{
    return SDL20_CreateThread(fn, NULL, data, pfnBeginThread, pfnEndThread);
}
#else
DECLSPEC SDL_Thread * SDLCALL
SDL_CreateThread(int (SDLCALL *fn)(void *), void *data)
{
    return SDL20_CreateThread(fn, NULL, data);
}
#endif


/* !!! FIXME: Removed from 2.0; do nothing. We can't even report failure. */
DECLSPEC void SDLCALL SDL_KillThread(SDL_Thread *thread) {}

/* This changed from an opaque pointer to an int in 2.0. */
typedef struct _SDL12_TimerID *SDL12_TimerID;
SDL_COMPILE_TIME_ASSERT(timer, sizeof(SDL12_TimerID) >= sizeof(SDL_TimerID));


DECLSPEC SDL12_TimerID SDLCALL
SDL_AddTimer(Uint32 interval, SDL12_NewTimerCallback callback, void *param)
{
    return (SDL12_TimerID) ((size_t) SDL20_AddTimer(interval, callback, param));
}

DECLSPEC SDL_bool SDLCALL
SDL_RemoveTimer(SDL12_TimerID id)
{
    return SDL20_RemoveTimer((SDL_TimerID) ((size_t)id));
}


typedef struct SDL12_RWops {
    int (SDLCALL *seek)(struct SDL12_RWops *context, int offset, int whence);
    int (SDLCALL *read)(struct SDL12_RWops *context, void *ptr, int size, int maxnum);
    int (SDLCALL *write)(struct SDL12_RWops *context, const void *ptr, int size, int num);
    int (SDLCALL *close)(struct SDL12_RWops *context);
    Uint32 type;
    void *padding[8];
    SDL_RWops *rwops20;
} SDL12_RWops;


DECLSPEC SDL12_RWops * SDLCALL
SDL_AllocRW(void)
{
    SDL12_RWops *rwops = (SDL12_RWops *) SDL20_malloc(sizeof (SDL12_RWops));
    if (!rwops)
        SDL20_OutOfMemory();
    return rwops;
}

DECLSPEC void SDLCALL
SDL_FreeRW(SDL12_RWops *rwops12)
{
    SDL20_free(rwops12);
}

static int SDLCALL
RWops20to12_seek(struct SDL12_RWops *rwops12, int offset, int whence)
{
    return rwops12->rwops20->seek(rwops12->rwops20, offset, whence);
}

static int SDLCALL
RWops20to12_read(struct SDL12_RWops *rwops12, void *ptr, int size, int maxnum)
{
    return rwops12->rwops20->read(rwops12->rwops20, ptr, size, maxnum);
}

static int SDLCALL
RWops20to12_write(struct SDL12_RWops *rwops12, const void *ptr, int size, int num)
{
    return rwops12->rwops20->write(rwops12->rwops20, ptr, size, num);
}

static int SDLCALL
RWops20to12_close(struct SDL12_RWops *rwops12)
{
    int rc = 0;
    if (rwops12)
    {
        rc = rwops12->rwops20->close(rwops12->rwops20);
        if (rc == 0)
            SDL_FreeRW(rwops12);
    }
    return rc;
}

static SDL12_RWops *
RWops20to12(SDL_RWops *rwops20)
{
    SDL12_RWops *rwops12;

    if (!rwops20)
        return NULL;

    rwops12 = SDL_AllocRW();
    if (!rwops12)
        return NULL;

    SDL20_zerop(rwops12);
    rwops12->type = rwops20->type;
    rwops12->rwops20 = rwops20;
    rwops12->seek = RWops20to12_seek;
    rwops12->read = RWops20to12_read;
    rwops12->write = RWops20to12_write;
    rwops12->close = RWops20to12_close;

    return rwops12;
}

DECLSPEC SDL12_RWops * SDLCALL
SDL_RWFromFile(const char *file, const char *mode)
{
    return RWops20to12(SDL20_RWFromFile(file, mode));
}

DECLSPEC SDL12_RWops * SDLCALL
SDL_RWFromFP(FILE *io, int autoclose)
{
    return RWops20to12(SDL20_RWFromFP(io, autoclose));
}

DECLSPEC SDL12_RWops * SDLCALL
SDL_RWFromMem(void *mem, int size)
{
    return RWops20to12(SDL20_RWFromMem(mem, size));
}

DECLSPEC SDL12_RWops * SDLCALL
SDL_RWFromConstMem(const void *mem, int size)
{
    return RWops20to12(SDL20_RWFromConstMem(mem, size));
}

#define READ_AND_BYTESWAP(endian, bits) \
    DECLSPEC Uint##bits SDLCALL SDL_Read##endian##bits(SDL12_RWops *rwops12) { \
        Uint##bits val; rwops12->read(rwops12, &val, sizeof (val), 1); \
        return SDL_Swap##endian##bits(val); \
    }

READ_AND_BYTESWAP(LE,16)
READ_AND_BYTESWAP(BE,16)
READ_AND_BYTESWAP(LE,32)
READ_AND_BYTESWAP(BE,32)
READ_AND_BYTESWAP(LE,64)
READ_AND_BYTESWAP(BE,64)
#undef READ_AND_BYTESWAP

#define BYTESWAP_AND_WRITE(endian, bits) \
    DECLSPEC int SDLCALL SDL_Write##endian##bits(SDL12_RWops *rwops12, Uint##bits val) { \
        val = SDL_Swap##endian##bits(val); \
        return rwops12->write(rwops12, &val, sizeof (val), 1); \
    }
BYTESWAP_AND_WRITE(LE,16)
BYTESWAP_AND_WRITE(BE,16)
BYTESWAP_AND_WRITE(LE,32)
BYTESWAP_AND_WRITE(BE,32)
BYTESWAP_AND_WRITE(LE,64)
BYTESWAP_AND_WRITE(BE,64)
#undef BYTESWAP_AND_WRITE


static Sint64 SDLCALL
RWops12to20_size(struct SDL_RWops *rwops20)
{
    SDL12_RWops *rwops12 = (SDL12_RWops *) rwops20->hidden.unknown.data1;
    int size = rwops20->hidden.unknown.data2;
    int pos;

    if (size != -1)
        return size;

    pos = rwops12->seek(rwops12, 0, SEEK_CUR);
    if (pos == -1)
        return -1;

    size = (Sint64) rwops12->seek(rwops12, 0, SEEK_END);
    if (size == -1)
        return -1;

    rwops12->seek(rwops12, pos, SEEK_SET);  /* !!! FIXME: and if this fails? */
    rwops20->hidden.unknown.data2 = size;
    return size;
}

static Sint64 SDLCALL
RWops12to20_seek(struct SDL_RWops *rwops20, Sint64 offset, int whence)
{
    /* !!! FIXME: fail if (offset) is too big */
    SDL12_RWops *rwops12 = (SDL12_RWops *) rwops20->hidden.unknown.data1;
    return (Sint64) rwops12->seek(rwops12, (int) offset, whence);
}

static size_t SDLCALL
RWops12to20_read(struct SDL_RWops *rwops20, void *ptr, size_t size, size_t maxnum)
{
    /* !!! FIXME: fail if (size) or (maxnum) is too big */
    SDL12_RWops *rwops12 = (SDL12_RWops *) rwops20->hidden.unknown.data1;
    return (size_t) rwops12->read(rwops12, ptr, (int) size, (int) maxnum);
}

static size_t SDLCALL
RWops12to20_write(struct SDL_RWops *rwops20, const void *ptr, size_t size, size_t num)
{
    /* !!! FIXME: fail if (size) or (maxnum) is too big */
    SDL12_RWops *rwops12 = (SDL12_RWops *) rwops20->hidden.unknown.data1;
    return (size_t) rwops12->write(rwops12, ptr, (int) size, (int) num);
}

static int SDLCALL
RWops12to20_close(struct SDL_RWops *rwops20)
{
    int rc = 0;
    if (rwops20)
    {
        SDL12_RWops *rwops12 = (SDL12_RWops *) rwops20->hidden.unknown.data1;
        rc = rwops12->close(rwops12);
        if (rc == 0)
            SDL20_FreeRW(rwops20);
    }
    return rc;
}

static SDL_RWops *
RWops12to20(SDL12_RWops *rwops12)
{
    SDL_RWops *rwops20;

    if (!rwops12)
        return NULL;

    rwops20 = SDL20_AllocRW();
    if (!rwops20)
        return NULL;

    SDL20_zerop(rwops20);
    rwops20->type = rwops12->type;
    rwops20->hidden.unknown.data1 = rwops12;
    rwops20->hidden.unknown.data2 = -1;  /* cached size of stream */
    rwops20->size = RWops12to20_size;
    rwops20->seek = RWops12to20_seek;
    rwops20->read = RWops12to20_read;
    rwops20->write = RWops12to20_write;
    rwops20->close = RWops12to20_close;
    return rwops20;
}

DECLSPEC SDL12_Surface * SDLCALL
SDL_LoadBMP_RW(SDL12_RWops *rwops12, int freerwops12)
{
    SDL_RWops *rwops20 = RWops12to20(rwops12);
    SDL_Surface *surface20 = SDL20_LoadBMP_RW(rwops20, freerwops12);
    SDL12_Surface *surface12 = Surface20to12(surface20);
    if (!freerwops12)  /* free our wrapper if SDL2 didn't close it. */
        SDL20_FreeRW(rwops20);
    if ((!surface12) && (surface20))
        SDL20_FreeSurface(surface20);
    return surface12;
}

DECLSPEC int SDLCALL
SDL_SaveBMP_RW(SDL12_Surface *surface12, SDL12_RWops *rwops12, int freerwops12)
{
    // !!! FIXME: wrap surface.
    SDL_RWops *rwops20 = RWops12to20(rwops12);
    const int retval = SDL20_SaveBMP_RW(surface12->surface20, rwops20, freerwops12);
    if (!freerwops12)  /* free our wrapper if SDL2 didn't close it. */
        SDL20_FreeRW(rwops20);
    return retval;
}

DECLSPEC SDL_AudioSpec * SDLCALL
SDL_LoadWAV_RW(SDL12_RWops *rwops12, int freerwops12,
               SDL_AudioSpec *spec, Uint8 **buf, Uint32 *len)
{
    SDL_RWops *rwops20 = RWops12to20(rwops12);
    SDL_AudioSpec *retval = SDL20_LoadWAV_RW(rwops20, freerwops12, spec, buf, len);
    if (!freerwops12)  /* free our wrapper if SDL2 didn't close it. */
        SDL20_FreeRW(rwops20);
    return retval;
}

/* vi: set ts=4 sw=4 expandtab: */