// SDL interface layer
// for the Build Engine
// by Jonathon Fowler (jonof@edgenetwk.com)
//
// Use SDL1.2 from http://www.libsdl.org

#include <stdlib.h>
#include <math.h>
#ifndef __APPLE__
# include "SDL.h"
#endif
#include "compat.h"
#include "sdlayer.h"
#include "cache1d.h"
#include "pragmas.h"
#include "a.h"
#include "build.h"
#include "osd.h"

#ifdef USE_OPENGL
# include "glbuild.h"
#endif

#if defined __APPLE__
# include <SDL/SDL.h>
# include "osxbits.h"
#elif defined HAVE_GTK2
# include "gtkbits.h"
#else
int startwin_open(void) { return 0; }
int startwin_close(void) { return 0; }
int startwin_puts(const char *s) { s=s; return 0; }
int startwin_idle(void *s) { return 0; }
int startwin_settitle(const char *s) { s=s; return 0; }
#endif

#define SURFACE_FLAGS	(SDL_SWSURFACE|SDL_HWPALETTE|SDL_HWACCEL)

// undefine to restrict windowed resolutions to conventional sizes
#define ANY_WINDOWED_SIZE

// fix for mousewheel
#define MWHEELTICKS 10
static unsigned int mwheelup, mwheeldown;

int   _buildargc = 1;
const char **_buildargv = NULL;
extern int app_main(int argc, const char *argv[]);

char quitevent=0, appactive=1;

// video
static SDL_Surface *sdl_surface;
int xres=-1, yres=-1, bpp=0, fullscreen=0, bytesperline, imageSize;
int frameplace=0, lockcount=0;
char modechange=1;
char offscreenrendering=0;
char videomodereset = 0;
char nofog=0;
static unsigned short sysgamma[3][256];
extern int curbrightness, gammabrightness;

#ifdef USE_OPENGL
// OpenGL stuff
static char nogl=0;
#endif

// input
char inputdevices=0;
char keystatus[256], keyfifo[KEYFIFOSIZ], keyfifoplc, keyfifoend;
unsigned char keyasciififo[KEYFIFOSIZ], keyasciififoplc, keyasciififoend;
static unsigned char keynames[256][24];
int mousex=0,mousey=0,mouseb=0;
int *joyaxis = NULL, joyb=0, *joyhat = NULL;
char joyisgamepad=0, joynumaxes=0, joynumbuttons=0, joynumhats=0;
int joyaxespresent=0;


void(*keypresscallback)(int,int) = 0;
void(*mousepresscallback)(int,int) = 0;
void(*joypresscallback)(int,int) = 0;

static unsigned char keytranslation[SDLK_LAST];
static int buildkeytranslationtable(void);

//static SDL_Surface * loadtarga(const char *fn);		// for loading the icon
static SDL_Surface * loadappicon(void);

int wm_msgbox(char *name, char *fmt, ...)
{
    char buf[2048];
    va_list va;

    va_start(va,fmt);
    vsprintf(buf,fmt,va);
    va_end(va);

#if defined(__APPLE__)
    return osx_msgbox(name, buf);
#elif defined HAVE_GTK2
    if (gtkbuild_msgbox(name, buf) >= 0) return 1;
#endif
    puts(buf);
    puts("   (press Return or Enter to continue)");
    getchar();

    return 0;
}

int wm_ynbox(char *name, char *fmt, ...)
{
    char buf[2048];
    char c;
    va_list va;
    int r;

    va_start(va,fmt);
    vsprintf(buf,fmt,va);
    va_end(va);

#if defined __APPLE__
    return osx_ynbox(name, buf);
#elif defined HAVE_GTK2
    if ((r = gtkbuild_ynbox(name, buf)) >= 0) return r;
#endif
    puts(buf);
    puts("   (type 'Y' or 'N', and press Return or Enter to continue)");
    do c = getchar(); while (c != 'Y' && c != 'y' && c != 'N' && c != 'n');
    if (c == 'Y' || c == 'y') return 1;

    return 0;
}

void wm_setapptitle(char *name)
{
    if (name)
    {
        Bstrncpy(apptitle, name, sizeof(apptitle)-1);
        apptitle[ sizeof(apptitle)-1 ] = 0;
    }

    SDL_WM_SetCaption(apptitle, NULL);

    startwin_settitle(apptitle);
}


//
//
// ---------------------------------------
//
// System
//
// ---------------------------------------
//
//

int main(int argc, char *argv[])
{
    int r;

    buildkeytranslationtable();

#ifdef HAVE_GTK2
    gtkbuild_init(&argc, &argv);
#endif
    startwin_open();

    _buildargc = argc;
    _buildargv = (const char**)argv;

    baselayer_init();
    r = app_main(_buildargc, _buildargv);

    startwin_close();
#ifdef HAVE_GTK2
    gtkbuild_exit(r);
#endif
    return r;
}


//
// initsystem() -- init SDL systems
//
int initsystem(void)
{
    const SDL_VideoInfo *vid;
    const SDL_version *linked = SDL_Linked_Version();
    SDL_version compiled;
    char drvname[32];

    SDL_VERSION(&compiled);

    initprintf("Initialising SDL system interface "
               "(compiled with SDL version %d.%d.%d, DLL version %d.%d.%d)\n",
               linked->major, linked->minor, linked->patch,
               compiled.major, compiled.minor, compiled.patch);

    if (SDL_Init(SDL_INIT_VIDEO //| SDL_INIT_TIMER
#ifdef NOSDLPARACHUTE
                 | SDL_INIT_NOPARACHUTE
#endif
                ))
    {
        initprintf("Initialisation failed! (%s)\n", SDL_GetError());
        return -1;
    }

    atexit(uninitsystem);

    frameplace = 0;
    lockcount = 0;

#ifdef USE_OPENGL
    if (loadgldriver(getenv("BUILD_GLDRV")))
    {
        initprintf("Failed loading OpenGL driver. GL modes will be unavailable.\n");
        nogl = 1;
    }
#endif

#ifndef __APPLE__
    {
        SDL_Surface *icon;
        //icon = loadtarga("icon.tga");
        icon = loadappicon();
        if (icon)
        {
            SDL_WM_SetIcon(icon, 0);
            SDL_FreeSurface(icon);
        }
    }
#endif

    if (SDL_VideoDriverName(drvname, 32))
        initprintf("Using \"%s\" video driver\n", drvname);

    // dump a quick summary of the graphics hardware
#ifdef DEBUGGINGAIDS
    vid = SDL_GetVideoInfo();
    initprintf("Video device information:\n");
    initprintf("  Can create hardware surfaces?          %s\n", (vid->hw_available)?"Yes":"No");
    initprintf("  Window manager available?              %s\n", (vid->wm_available)?"Yes":"No");
    initprintf("  Accelerated hardware blits?            %s\n", (vid->blit_hw)?"Yes":"No");
    initprintf("  Accelerated hardware colourkey blits?  %s\n", (vid->blit_hw_CC)?"Yes":"No");
    initprintf("  Accelerated hardware alpha blits?      %s\n", (vid->blit_hw_A)?"Yes":"No");
    initprintf("  Accelerated software blits?            %s\n", (vid->blit_sw)?"Yes":"No");
    initprintf("  Accelerated software colourkey blits?  %s\n", (vid->blit_sw_CC)?"Yes":"No");
    initprintf("  Accelerated software alpha blits?      %s\n", (vid->blit_sw_A)?"Yes":"No");
    initprintf("  Accelerated colour fills?              %s\n", (vid->blit_fill)?"Yes":"No");
    initprintf("  Total video memory:                    %dKB\n", vid->video_mem);
#endif

    return 0;
}


//
// uninitsystem() -- uninit SDL systems
//
void uninitsystem(void)
{
    uninitinput();
    uninitmouse();
    uninittimer();

    SDL_Quit();

#ifdef USE_OPENGL
    unloadgldriver();
#endif
}


//
// initprintf() -- prints a string to the intitialization window
//
void initprintf(const char *f, ...)
{
    va_list va;
    char buf[1024];

    va_start(va, f);
    vprintf(f,va);
    va_end(va);

    va_start(va, f);
    Bvsnprintf(buf, 1024, f, va);
    va_end(va);
    OSD_Printf(buf);

    startwin_puts(buf);
    startwin_idle(NULL);
}


//
// debugprintf() -- prints a debug string to stderr
//
void debugprintf(const char *f, ...)
{
#ifdef DEBUGGINGAIDS
    va_list va;

    va_start(va,f);
    Bvfprintf(stderr, f, va);
    va_end(va);
#endif
}


//
//
// ---------------------------------------
//
// All things Input
//
// ---------------------------------------
//
//

static char mouseacquired=0,moustat=0;
static int joyblast=0;
static SDL_Joystick *joydev = NULL;

//
// initinput() -- init input system
//
int initinput(void)
{
    int i,j;

#ifdef __APPLE__
    // force OS X to operate in >1 button mouse mode so that LMB isn't adulterated
    if (!getenv("SDL_HAS3BUTTONMOUSE")) putenv("SDL_HAS3BUTTONMOUSE=1");
#endif

    if (SDL_EnableKeyRepeat(250, 30)) initprintf("Error enabling keyboard repeat.\n");
    inputdevices = 1|2;	// keyboard (1) and mouse (2)
    mouseacquired = 0;

    SDL_EnableUNICODE(1);	// let's hope this doesn't hit us too hard

    memset(keynames,0,sizeof(keynames));
    for (i=0; i<SDLK_LAST; i++)
    {
        if (!keytranslation[i]) continue;
        strncpy((char *)keynames[ keytranslation[i] ], SDL_GetKeyName(i), sizeof(keynames[i])-1);
    }

    if (!SDL_InitSubSystem(SDL_INIT_JOYSTICK))
    {
        i = SDL_NumJoysticks();
        initprintf("%d joystick(s) found\n",i);
        for (j=0;j<i;j++) initprintf("  %d. %s\n", j+1, SDL_JoystickName(j));
        joydev = SDL_JoystickOpen(0);
        if (joydev)
        {
            SDL_JoystickEventState(SDL_ENABLE);
            inputdevices |= 4;

            joynumaxes    = SDL_JoystickNumAxes(joydev);
            joynumbuttons = min(32,SDL_JoystickNumButtons(joydev));
            joynumhats    = SDL_JoystickNumHats(joydev);
            initprintf("Joystick 1 has %d axes, %d buttons, and %d hat(s).\n",
                       joynumaxes,joynumbuttons,joynumhats);

            joyaxis = (int *)Bcalloc(joynumaxes, sizeof(int));
            joyhat = (int *)Bcalloc(joynumhats, sizeof(int));
        }
    }

    return 0;
}

//
// uninitinput() -- uninit input system
//
void uninitinput(void)
{
    uninitmouse();

    if (joydev)
    {
        SDL_JoystickClose(joydev);
        joydev = NULL;
    }
}

const unsigned char *getkeyname(int num)
{
    if ((unsigned)num >= 256) return NULL;
    return keynames[num];
}

const unsigned char *getjoyname(int what, int num)
{
    static char tmp[64];

    switch (what)
    {
    case 0:	// axis
        if ((unsigned)num > (unsigned)joynumaxes) return NULL;
        sprintf(tmp,"Axis %d",num);
        return (unsigned char *)tmp;

    case 1: // button
        if ((unsigned)num > (unsigned)joynumbuttons) return NULL;
        sprintf(tmp,"Button %d",num);
        return (unsigned char *)tmp;

    case 2: // hat
        if ((unsigned)num > (unsigned)joynumhats) return NULL;
        sprintf(tmp,"Hat %d",num);
        return (unsigned char *)tmp;

    default:
        return NULL;
    }
}

//
// bgetchar, bkbhit, bflushchars -- character-based input functions
//
unsigned char bgetchar(void)
{
    unsigned char c;
    if (keyasciififoplc == keyasciififoend) return 0;
    c = keyasciififo[keyasciififoplc];
    keyasciififoplc = ((keyasciififoplc+1)&(KEYFIFOSIZ-1));
    return c;
}

int bkbhit(void)
{
    return (keyasciififoplc != keyasciififoend);
}

void bflushchars(void)
{
    keyasciififoplc = keyasciififoend = 0;
}


//
// set{key|mouse|joy}presscallback() -- sets a callback which gets notified when keys are pressed
//
void setkeypresscallback(void(*callback)(int, int)) { keypresscallback = callback; }
void setmousepresscallback(void(*callback)(int, int)) { mousepresscallback = callback; }
void setjoypresscallback(void(*callback)(int, int)) { joypresscallback = callback; }

//
// initmouse() -- init mouse input
//
int initmouse(void)
{
    moustat=1;
    grabmouse(1);
    return 0;
}

//
// uninitmouse() -- uninit mouse input
//
void uninitmouse(void)
{
    grabmouse(0);
    moustat=0;
}


//
// grabmouse() -- show/hide mouse cursor
//
void grabmouse(char a)
{
    if (appactive && moustat)
    {
        if (a != mouseacquired)
        {
// #ifndef DEBUGGINGAIDS
#if 1
            SDL_GrabMode g;

            g = SDL_WM_GrabInput(a ? SDL_GRAB_ON : SDL_GRAB_OFF);
            mouseacquired = (g == SDL_GRAB_ON);

            SDL_ShowCursor(mouseacquired ? SDL_DISABLE : SDL_ENABLE);
#else
            mouseacquired = a;
#endif
        }
    }
    else
    {
        mouseacquired = a;
    }
    mousex = mousey = 0;
}


//
// readmousexy() -- return mouse motion information
//
void readmousexy(int *x, int *y)
{
    if (!mouseacquired || !appactive || !moustat) { *x = *y = 0; return; }
    *x = mousex;
    *y = mousey;
    mousex = mousey = 0;
}

//
// readmousebstatus() -- return mouse button information
//
void readmousebstatus(int *b)
{
    if (!mouseacquired || !appactive || !moustat) *b = 0;
    else *b = mouseb;
}

//
// setjoydeadzone() -- sets the dead and saturation zones for the joystick
//
void setjoydeadzone(int axis, unsigned short dead, unsigned short satur)
{}


//
// getjoydeadzone() -- gets the dead and saturation zones for the joystick
//
void getjoydeadzone(int axis, unsigned short *dead, unsigned short *satur)
{
    *dead = *satur = 0;
}


//
// releaseallbuttons()
//
void releaseallbuttons(void)
{}


//
//
// ---------------------------------------
//
// All things Timer
// Ken did this
//
// ---------------------------------------
//
//

static Uint32 timerfreq=0;
static Uint32 timerlastsample=0;
Uint32 timerticspersec=0;
static void(*usertimercallback)(void) = NULL;

//
// inittimer() -- initialise timer
//
int inittimer(int tickspersecond)
{
    if (timerfreq) return 0;	// already installed

//    initprintf("Initialising timer\n");

    timerfreq = 1000;
    timerticspersec = tickspersecond;
    timerlastsample = SDL_GetTicks() * timerticspersec / timerfreq;

    usertimercallback = NULL;

    return 0;
}

//
// uninittimer() -- shut down timer
//
void uninittimer(void)
{
    if (!timerfreq) return;

    timerfreq=0;
}

//
// sampletimer() -- update totalclock
//
void sampletimer(void)
{
    Uint32 i;
    int n;

    if (!timerfreq) return;

    i = SDL_GetTicks();
    n = (int)(i * timerticspersec / timerfreq) - timerlastsample;
    if (n>0)
    {
        totalclock += n;
        timerlastsample += n;
    }

    if (usertimercallback) for (; n>0; n--) usertimercallback();
}

//
// getticks() -- returns the sdl ticks count
//
unsigned int getticks(void)
{
    return (unsigned int)SDL_GetTicks();
}


//
// gettimerfreq() -- returns the number of ticks per second the timer is configured to generate
//
int gettimerfreq(void)
{
    return timerticspersec;
}


//
// installusertimercallback() -- set up a callback function to be called when the timer is fired
//
void(*installusertimercallback(void(*callback)(void)))(void)
{
    void(*oldtimercallback)(void);

    oldtimercallback = usertimercallback;
    usertimercallback = callback;

    return oldtimercallback;
}



//
//
// ---------------------------------------
//
// All things Video
//
// ---------------------------------------
//
//


//
// getvalidmodes() -- figure out what video modes are available
//
static int sortmodes(const struct validmode_t *a, const struct validmode_t *b)
{
    int x;

    if ((x = a->fs   - b->fs)   != 0) return x;
    if ((x = a->bpp  - b->bpp)  != 0) return x;
    if ((x = a->xdim - b->xdim) != 0) return x;
    if ((x = a->ydim - b->ydim) != 0) return x;

    return 0;
}
static char modeschecked=0;
void getvalidmodes(void)
{
    static int cdepths[] =
    {
        8,
#ifdef USE_OPENGL
        16,24,32,
#endif
        0
    };
    static int defaultres[][2] =
    {
        {1280,1024}
        ,{1280,960},{1152,864},{1024,768},{800,600},{640,480},
        {640,400},{512,384},{480,360},{400,300},{320,240},{320,200},{0,0}
    };
    SDL_Rect **modes;
    SDL_PixelFormat pf = { NULL, 8, 1, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0 };
    int i, j, maxx=0, maxy=0;

    if (modeschecked) return;

    validmodecnt=0;
    initprintf("Detecting video modes:\n");

#define ADDMODE(x,y,c,f) if (validmodecnt<MAXVALIDMODES) { \
	int mn; \
	for(mn=0;mn<validmodecnt;mn++) \
		if (validmode[mn].xdim==x && validmode[mn].ydim==y && \
		    validmode[mn].bpp==c  && validmode[mn].fs==f) break; \
	if (mn==validmodecnt) { \
		validmode[validmodecnt].xdim=x; \
		validmode[validmodecnt].ydim=y; \
		validmode[validmodecnt].bpp=c; \
		validmode[validmodecnt].fs=f; \
		validmodecnt++; \
		initprintf("  - %dx%d %d-bit %s\n", x, y, c, (f&1)?"fullscreen":"windowed"); \
	} \
}

#define CHECK(w,h) if ((w < maxx) && (h < maxy))

    // do fullscreen modes first
    for (j=0; cdepths[j]; j++)
    {
#ifdef USE_OPENGL
        if (nogl && cdepths[j] > 8) continue;
#endif
        pf.BitsPerPixel = cdepths[j];
        pf.BytesPerPixel = cdepths[j] >> 3;

        modes = SDL_ListModes(&pf, SURFACE_FLAGS | SDL_FULLSCREEN);
        if (modes == (SDL_Rect **)0)
        {
            if (cdepths[j] > 8) cdepths[j] = -1;
            continue;
        }

        if (modes == (SDL_Rect **)-1)
        {
            for (i=0; defaultres[i][0]; i++)
                ADDMODE(defaultres[i][0],defaultres[i][1],cdepths[j],1)
            }
        else
        {
            for (i=0; modes[i]; i++)
            {
                if ((modes[i]->w > MAXXDIM) || (modes[i]->h > MAXYDIM)) continue;

                ADDMODE(modes[i]->w, modes[i]->h, cdepths[j], 1)

                if ((modes[i]->w > maxx) && (modes[i]->h > maxy))
                {
                    maxx = modes[i]->w;
                    maxy = modes[i]->h;
                }
            }
        }
    }

    if (maxx == 0 && maxy == 0)
    {
        initprintf("No fullscreen modes available!\n");
        maxx = MAXXDIM; maxy = MAXYDIM;
    }

    // add windowed modes next
    for (j=0; cdepths[j]; j++)
    {
#ifdef USE_OPENGL
        if (nogl && cdepths[j] > 8) continue;
#endif
        if (cdepths[j] < 0) continue;
        for (i=0; defaultres[i][0]; i++)
            CHECK(defaultres[i][0],defaultres[i][1])
            ADDMODE(defaultres[i][0],defaultres[i][1],cdepths[j],0)
        }

#undef CHECK
#undef ADDMODE

    qsort((void*)validmode, validmodecnt, sizeof(struct validmode_t), (int(*)(const void*,const void*))sortmodes);

    modeschecked=1;
}


//
// checkvideomode() -- makes sure the video mode passed is legal
//
int checkvideomode(int *x, int *y, int c, int fs, int forced)
{
    int i, nearest=-1, dx, dy, odx=9999, ody=9999;

    getvalidmodes();

    if (c>8
#ifdef USE_OPENGL
            && nogl
#endif
       ) return -1;

    // fix up the passed resolution values to be multiples of 8
    // and at least 320x200 or at most MAXXDIMxMAXYDIM
    if (*x < 320) *x = 320;
    if (*y < 200) *y = 200;
    if (*x > MAXXDIM) *x = MAXXDIM;
    if (*y > MAXYDIM) *y = MAXYDIM;
    *x &= 0xfffffff8l;

    for (i=0; i<validmodecnt; i++)
    {
        if (validmode[i].bpp != c) continue;
        if (validmode[i].fs != fs) continue;
        dx = klabs(validmode[i].xdim - *x);
        dy = klabs(validmode[i].ydim - *y);
        if (!(dx | dy))
        {
            // perfect match
            nearest = i;
            break;
        }
        if ((dx <= odx) && (dy <= ody))
        {
            nearest = i;
            odx = dx; ody = dy;
        }
    }

#ifdef ANY_WINDOWED_SIZE
    if (!forced && (fs&1) == 0 && (nearest < 0 || (validmode[nearest].xdim!=*x || validmode[nearest].ydim!=*y)))
        return 0x7fffffffl;
#endif

    if (nearest < 0)
    {
        // no mode that will match (eg. if no fullscreen modes)
        return -1;
    }

    *x = validmode[nearest].xdim;
    *y = validmode[nearest].ydim;

    return nearest;		// JBF 20031206: Returns the mode number
}


//
// setvideomode() -- set SDL video mode
//
int setvideomode(int x, int y, int c, int fs)
{
    int modenum, regrab = 0;
    static int warnonce = 0;

    if ((fs == fullscreen) && (x == xres) && (y == yres) && (c == bpp) &&
            !videomodereset)
    {
        OSD_ResizeDisplay(xres,yres);
        return 0;
    }

    if (checkvideomode(&x,&y,c,fs,0) < 0) return -1;

    startwin_close();

    if (mouseacquired)
    {
        regrab = 1;
        grabmouse(0);
    }

    if (lockcount) while (lockcount) enddrawing();

#if defined(USE_OPENGL)
    if (bpp > 8 && sdl_surface) polymost_glreset();
#endif

    // restore gamma before we change video modes if it was changed
    if (sdl_surface && gammabrightness)
    {
        SDL_SetGammaRamp(sysgamma[0], sysgamma[1], sysgamma[2]);
        gammabrightness = 0;	// redetect on next mode switch
    }

#if defined(USE_OPENGL)
    if (c > 8)
    {
        int i, j, multisamplecheck = (glmultisample > 0);
        struct
        {
            SDL_GLattr attr;
            int value;
        }
        attributes[] =
        {
#if 0
            { SDL_GL_RED_SIZE, 8 },
            { SDL_GL_GREEN_SIZE, 8 },
            { SDL_GL_BLUE_SIZE, 8 },
            { SDL_GL_ALPHA_SIZE, 8 },
            { SDL_GL_BUFFER_SIZE, c },
            { SDL_GL_STENCIL_SIZE, 0 },
            { SDL_GL_ACCUM_RED_SIZE, 0 },
            { SDL_GL_ACCUM_GREEN_SIZE, 0 },
            { SDL_GL_ACCUM_BLUE_SIZE, 0 },
            { SDL_GL_ACCUM_ALPHA_SIZE, 0 },
            { SDL_GL_DEPTH_SIZE, 24 },
#endif
            { SDL_GL_DOUBLEBUFFER, 1 },
            { SDL_GL_MULTISAMPLEBUFFERS, glmultisample > 0 },
            { SDL_GL_MULTISAMPLESAMPLES, glmultisample },
        };

        if (nogl) return -1;

        initprintf("Setting video mode %dx%d (%d-bpp %s)\n",
                   x,y,c, ((fs&1) ? "fullscreen" : "windowed"));
        do
        {
            for (i=0; i < (int)(sizeof(attributes)/sizeof(attributes[0])); i++)
            {
                j = attributes[i].value;
                if (!multisamplecheck &&
                        (attributes[i].attr == SDL_GL_MULTISAMPLEBUFFERS ||
                         attributes[i].attr == SDL_GL_MULTISAMPLESAMPLES)
                   )
                {
                    j = 0;
                }
                SDL_GL_SetAttribute(attributes[i].attr, j);
            }

            sdl_surface = SDL_SetVideoMode(x, y, c, SDL_OPENGL | ((fs&1)?SDL_FULLSCREEN:0));
            if (!sdl_surface)
            {
                if (multisamplecheck)
                {
                    initprintf("Multisample mode not possible. Retrying without multisampling.\n");
                    glmultisample = 0;
                    continue;
                }
                initprintf("Unable to set video mode!\n");
                return -1;
            }
        }
        while (multisamplecheck--);
    }
    else
#endif
    {
        initprintf("Setting video mode %dx%d (%d-bpp %s)\n",
                   x,y,c, ((fs&1) ? "fullscreen" : "windowed"));
        sdl_surface = SDL_SetVideoMode(x, y, c, SURFACE_FLAGS | ((fs&1)?SDL_FULLSCREEN:0));
        if (!sdl_surface)
        {
            initprintf("Unable to set video mode!\n");
            return -1;
        }
    }

#if 0
    {
        char flags[512] = "";
#define FLAG(x,y) if ((sdl_surface->flags & x) == x) { strcat(flags, y); strcat(flags, " "); }
        FLAG(SDL_HWSURFACE, "HWSURFACE") else
            FLAG(SDL_SWSURFACE, "SWSURFACE")
            FLAG(SDL_ASYNCBLIT, "ASYNCBLIT")
            FLAG(SDL_ANYFORMAT, "ANYFORMAT")
            FLAG(SDL_HWPALETTE, "HWPALETTE")
            FLAG(SDL_DOUBLEBUF, "DOUBLEBUF")
            FLAG(SDL_FULLSCREEN, "FULLSCREEN")
            FLAG(SDL_OPENGL, "OPENGL")
            FLAG(SDL_OPENGLBLIT, "OPENGLBLIT")
            FLAG(SDL_RESIZABLE, "RESIZABLE")
            FLAG(SDL_HWACCEL, "HWACCEL")
            FLAG(SDL_SRCCOLORKEY, "SRCCOLORKEY")
            FLAG(SDL_RLEACCEL, "RLEACCEL")
            FLAG(SDL_SRCALPHA, "SRCALPHA")
            FLAG(SDL_PREALLOC, "PREALLOC")
#undef FLAG
            initprintf("SDL Surface flags: %s\n", flags);
    }
#endif

    {
        //static char t[384];
        //sprintf(t, "%s (%dx%d %s)", apptitle, x, y, ((fs) ? "fullscreen" : "windowed"));
        SDL_WM_SetCaption(apptitle, 0);
    }

#ifdef USE_OPENGL
    if (c > 8)
    {
        char *p,*p2,*p3;
        int i;

        polymost_glreset();

        bglEnable(GL_TEXTURE_2D);
        bglShadeModel(GL_SMOOTH); //GL_FLAT
        bglClearColor(0,0,0,0.5); //Black Background
        bglHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST); //Use FASTEST for ortho!
        bglHint(GL_LINE_SMOOTH_HINT,GL_NICEST);
        bglDisable(GL_DITHER);

        glinfo.vendor     = (const char *)bglGetString(GL_VENDOR);
        glinfo.renderer   = (const char *)bglGetString(GL_RENDERER);
        glinfo.version    = (const char *)bglGetString(GL_VERSION);
        glinfo.extensions = (const char *)bglGetString(GL_EXTENSIONS);

        glinfo.maxanisotropy = 1.0;
        glinfo.bgra = 0;
        glinfo.texcompr = 0;

        // process the extensions string and flag stuff we recognize
        p = Bstrdup(glinfo.extensions);
        p3 = p;
        while ((p2 = Bstrtoken(p3==p?p:NULL, " ", (char**)&p3, 1)) != NULL)
        {
            if (!Bstrcmp(p2, "GL_EXT_texture_filter_anisotropic"))
            {
                // supports anisotropy. get the maximum anisotropy level
                bglGetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &glinfo.maxanisotropy);
            }
            else if (!Bstrcmp(p2, "GL_EXT_texture_edge_clamp") ||
                     !Bstrcmp(p2, "GL_SGIS_texture_edge_clamp"))
            {
                // supports GL_CLAMP_TO_EDGE or GL_CLAMP_TO_EDGE_SGIS
                glinfo.clamptoedge = 1;
            }
            else if (!Bstrcmp(p2, "GL_EXT_bgra"))
            {
                // support bgra textures
                glinfo.bgra = 1;
            }
            else if (!Bstrcmp(p2, "GL_ARB_texture_compression"))
            {
                // support texture compression
                glinfo.texcompr = 1;
            }
            else if (!Bstrcmp(p2, "GL_ARB_texture_non_power_of_two"))
            {
                // support non-power-of-two texture sizes
                glinfo.texnpot = 1;
            }
            else if (!Bstrcmp(p2, "WGL_3DFX_gamma_control"))
            {
                // 3dfx cards have issues with fog
                nofog = 1;
                if (!(warnonce&1)) initprintf("3dfx card detected: OpenGL fog disabled\n");
                warnonce |= 1;
            }
            else if (!Bstrcmp(p2, "GL_ARB_multisample"))
            {
                // supports multisampling
                glinfo.multisample = 1;
            }
            else if (!Bstrcmp(p2, "GL_NV_multisample_filter_hint"))
            {
                // supports nvidia's multisample hint extension
                glinfo.nvmultisamplehint = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_ARB_fragment_program"))
            {
                glinfo.arbfp = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_ARB_depth_texture"))
            {
                glinfo.depthtex = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_ARB_shadow"))
            {
                glinfo.shadow = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_EXT_framebuffer_object"))
            {
                glinfo.fbos = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_NV_texture_rectangle") ||
                     !Bstrcmp((char *)p2, "GL_EXT_texture_rectangle"))
            {
                glinfo.rect = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_ARB_multitexture"))
            {
                glinfo.multitex = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_ARB_texture_env_combine"))
            {
                glinfo.envcombine = 1;
            }
            else if (!Bstrcmp((char *)p2, "GL_ARB_vertex_buffer_object"))
            {
                glinfo.vbos = 1;
            }
        }
        Bfree(p);
    }
#endif

    xres = x;
    yres = y;
    bpp = c;
    fullscreen = fs;
    //bytesperline = sdl_surface->pitch;
    //imageSize = bytesperline*yres;
    numpages = c>8?2:1;
    frameplace = 0;
    lockcount = 0;
    modechange=1;
    videomodereset = 0;
    OSD_ResizeDisplay(xres,yres);

    // save the current system gamma to determine if gamma is available
    if (!gammabrightness)
    {
        float f = 1.0 + ((float)curbrightness / 10.0);
        if (SDL_GetGammaRamp(sysgamma[0], sysgamma[1], sysgamma[2]) >= 0)
            gammabrightness = 1;

        // see if gamma really is working by trying to set the brightness
        if (gammabrightness && SDL_SetGamma(f,f,f) < 0)
            gammabrightness = 0;	// nope
    }

    // setpalettefade will set the palette according to whether gamma worked
    setpalettefade(palfadergb.r, palfadergb.g, palfadergb.b, palfadedelta);

    //if (c==8) setpalette(0,256,0);
    //baselayer_onvideomodechange(c>8);

    if (regrab) grabmouse(1);

    return 0;
}


//
// resetvideomode() -- resets the video system
//
void resetvideomode(void)
{
    videomodereset = 1;
    modeschecked = 0;
}


//
// begindrawing() -- locks the framebuffer for drawing
//
void begindrawing(void)
{
    int i,j;

    if (bpp > 8)
    {
        if (offscreenrendering) return;
        frameplace = 0;
        bytesperline = 0;
        imageSize = 0;
        modechange = 0;
        return;
    }

    // lock the frame
    if (lockcount++ > 0)
        return;

    if (offscreenrendering) return;

    if (SDL_MUSTLOCK(sdl_surface)) SDL_LockSurface(sdl_surface);
    frameplace = (int)sdl_surface->pixels;

    if (sdl_surface->pitch != bytesperline || modechange)
    {
        bytesperline = sdl_surface->pitch;
        imageSize = bytesperline*yres;
        setvlinebpl(bytesperline);

        j = 0;
        for (i=0;i<=ydim;i++) ylookup[i] = j, j += bytesperline;
        modechange=0;
    }
}


//
// enddrawing() -- unlocks the framebuffer
//
void enddrawing(void)
{
    if (bpp > 8)
    {
        if (!offscreenrendering) frameplace = 0;
        return;
    }

    if (!frameplace) return;
    if (lockcount > 1) { lockcount--; return; }
    if (!offscreenrendering) frameplace = 0;
    if (lockcount == 0) return;
    lockcount = 0;

    if (offscreenrendering) return;

    if (SDL_MUSTLOCK(sdl_surface)) SDL_UnlockSurface(sdl_surface);
}


//
// showframe() -- update the display
//
void showframe(int w)
{
    int i,j;

#ifdef USE_OPENGL
    if (bpp > 8)
    {
        if (palfadedelta)
        {
            bglMatrixMode(GL_PROJECTION);
            bglPushMatrix();
            bglLoadIdentity();
            bglMatrixMode(GL_MODELVIEW);
            bglPushMatrix();
            bglLoadIdentity();

            bglDisable(GL_DEPTH_TEST);
            bglDisable(GL_ALPHA_TEST);
            bglDisable(GL_TEXTURE_2D);

            bglEnable(GL_BLEND);
            bglColor4ub(palfadergb.r, palfadergb.g, palfadergb.b, palfadedelta);

            bglBegin(GL_QUADS);
            bglVertex2i(-1, -1);
            bglVertex2i(1, -1);
            bglVertex2i(1, 1);
            bglVertex2i(-1, 1);
            bglEnd();

            bglMatrixMode(GL_MODELVIEW);
            bglPopMatrix();
            bglMatrixMode(GL_PROJECTION);
            bglPopMatrix();
        }

        SDL_GL_SwapBuffers();
        return;
    }
#endif

    if (offscreenrendering) return;

    if (lockcount)
    {
        printf("Frame still locked %d times when showframe() called.\n", lockcount);
        while (lockcount) enddrawing();
    }

    SDL_Flip(sdl_surface);
}


//
// setpalette() -- set palette values
//
int setpalette(int start, int num, char *dapal)
{
    SDL_Color pal[256];
    int i,n;

    if (bpp > 8) return 0;	// no palette in opengl

    copybuf(curpalettefaded, pal, 256);

    for (i=start, n=num; n>0; i++, n--)
    {
        /*
        pal[i].b = dapal[0] << 2;
        pal[i].g = dapal[1] << 2;
        pal[i].r = dapal[2] << 2;
        */
        curpalettefaded[i].f = pal[i].unused = 0;
        dapal += 4;
    }

    //return SDL_SetPalette(sdl_surface, SDL_LOGPAL|SDL_PHYSPAL, pal, 0, 256);
    return SDL_SetColors(sdl_surface, pal, 0, 256);
}

//
// getpalette() -- get palette values
//
/*
int getpalette(int start, int num, char *dapal)
{
	int i;
	SDL_Palette *pal;

	// we shouldn't need to lock the surface to get the palette
	pal = sdl_surface->format->palette;

	for (i=num; i>0; i--, start++) {
		dapal[0] = pal->colors[start].b >> 2;
		dapal[1] = pal->colors[start].g >> 2;
		dapal[2] = pal->colors[start].r >> 2;
		dapal += 4;
	}

	return 1;
}
*/

//
// setgamma
//
int setgamma(float ro, float go, float bo)
{
    return SDL_SetGamma(ro,go,bo);
}

#ifndef __APPLE__
extern struct sdlappicon sdlappicon;
static SDL_Surface * loadappicon(void)
{
    SDL_Surface *surf;

    surf = SDL_CreateRGBSurfaceFrom((void*)sdlappicon.pixels,
                                    sdlappicon.width, sdlappicon.height, 32, sdlappicon.width*4,
                                    0xffl,0xff00l,0xff0000l,0xff000000l);

    return surf;
}
#endif

//
//
// ---------------------------------------
//
// Miscellany
//
// ---------------------------------------
//
//


//
// handleevents() -- process the SDL message queue
//   returns !0 if there was an important event worth checking (like quitting)
//
int handleevents(void)
{
    int code, rv=0, j;
    SDL_Event ev;

#define SetKey(key,state) { \
	keystatus[key] = state; \
		if (state) { \
	keyfifo[keyfifoend] = key; \
	keyfifo[(keyfifoend+1)&(KEYFIFOSIZ-1)] = state; \
	keyfifoend = ((keyfifoend+2)&(KEYFIFOSIZ-1)); \
		} \
}

    while (SDL_PollEvent(&ev))
    {
        switch (ev.type)
        {
        case SDL_KEYDOWN:
        case SDL_KEYUP:
            code = keytranslation[ev.key.keysym.sym];

            if (ev.key.keysym.unicode != 0 && ev.key.type == SDL_KEYDOWN &&
                    (ev.key.keysym.unicode & 0xff80) == 0 &&
                    ((keyasciififoend+1)&(KEYFIFOSIZ-1)) != keyasciififoplc)
            {
                keyasciififo[keyasciififoend] = ev.key.keysym.unicode & 0x7f;
                keyasciififoend = ((keyasciififoend+1)&(KEYFIFOSIZ-1));
            }

            // hook in the osd
            if (OSD_HandleKey(code, (ev.key.type == SDL_KEYDOWN)) == 0)
                break;

            if (ev.key.type == SDL_KEYDOWN)
            {
                if (!keystatus[code])
                {
                    SetKey(code, 1);
                    if (keypresscallback)
                        keypresscallback(code, 1);
                }
            }
            else
            {
                SetKey(code, 0);
                if (keypresscallback)
                    keypresscallback(code, 0);
            }
            break;

        case SDL_ACTIVEEVENT:
            if (ev.active.state & SDL_APPINPUTFOCUS)
            {
                appactive = ev.active.gain;
#ifndef DEBUGGINGAIDS
                if (mouseacquired && moustat)
                {
                    if (appactive)
                    {
                        SDL_WM_GrabInput(SDL_GRAB_ON);
                        SDL_ShowCursor(SDL_DISABLE);
                    }
                    else
                    {
                        SDL_WM_GrabInput(SDL_GRAB_OFF);
                        SDL_ShowCursor(SDL_ENABLE);
                    }
                }
#endif
                rv=-1;
            }
            break;

        case SDL_MOUSEBUTTONDOWN:
        case SDL_MOUSEBUTTONUP:
            switch (ev.button.button)
            {
            case SDL_BUTTON_LEFT:
                j = 0; break;
            case SDL_BUTTON_RIGHT:
                j = 1; break;
            case SDL_BUTTON_MIDDLE:
                j = 2; break;
            default:
                j = ev.button.button; break;
            }
            if (j<0) break;

            if (ev.button.state == SDL_PRESSED)
            {
                if (ev.button.button == SDL_BUTTON_WHEELUP)
                {
                    mwheelup = totalclock;
                }
                if (ev.button.button == SDL_BUTTON_WHEELDOWN)
                {
                    mwheeldown = totalclock;
                }
                mouseb |= (1<<j);
            }
            else
            {
                if (j < 4) mouseb &= ~(1<<j);
            }

            if (mousepresscallback)
                mousepresscallback(j+1, ev.button.state == SDL_PRESSED);
            break;

        case SDL_MOUSEMOTION:
            if (appactive)
            {
                mousex += ev.motion.xrel;
                mousey += ev.motion.yrel;
            }
            break;

        case SDL_JOYAXISMOTION:
            if (appactive && ev.jaxis.axis < joynumaxes)
                joyaxis[ ev.jaxis.axis ] = ev.jaxis.value * 10000 / 32767;
            break;

        case SDL_JOYHATMOTION:
        {
            int hatvals[16] =
            {
                -1,	// centre
                0, 	// up 1
                9000,	// right 2
                4500,	// up+right 3
                18000,	// down 4
                -1,	// down+up!! 5
                13500,	// down+right 6
                -1,	// down+right+up!! 7
                27000,	// left 8
                27500,	// left+up 9
                -1,	// left+right!! 10
                -1,	// left+right+up!! 11
                22500,	// left+down 12
                -1,	// left+down+up!! 13
                -1,	// left+down+right!! 14
                -1,	// left+down+right+up!! 15
            };
            if (appactive && ev.jhat.hat < joynumhats)
                joyhat[ ev.jhat.hat ] = hatvals[ ev.jhat.value & 15 ];
            break;
        }

        case SDL_JOYBUTTONDOWN:
        case SDL_JOYBUTTONUP:
            if (appactive && ev.jbutton.button < joynumbuttons)
            {
                if (ev.jbutton.state == SDL_PRESSED)
                    joyb |= 1 << ev.jbutton.button;
                else
                    joyb &= ~(1 << ev.jbutton.button);
            }
            break;

        case SDL_QUIT:
            quitevent = 1;
            rv=-1;
            break;

        default:
            //printOSD("Got event (%d)\n", ev.type);
            break;
        }
    }

    sampletimer();

    if (moustat)
    {
        if ((mwheelup) && (mwheelup <= (unsigned)(totalclock - MWHEELTICKS)))
        {
            mouseb &= ~16;
            mwheelup = 0;
        }
        if ((mwheeldown) && (mwheeldown <= (unsigned)(totalclock - MWHEELTICKS)))
        {
            mouseb &= ~32;
            mwheeldown = 0;
        }
    }

    startwin_idle(NULL);

#undef SetKey

    return rv;
}

inline void idle(void)
{
    usleep(1);
}

static int buildkeytranslationtable(void)
{
    memset(keytranslation,0,sizeof(keytranslation));

#define MAP(x,y) keytranslation[x] = y
    MAP(SDLK_BACKSPACE,	0xe);
    MAP(SDLK_TAB,		0xf);
    MAP(SDLK_RETURN,	0x1c);
    MAP(SDLK_PAUSE,		0x59);	// 0x1d + 0x45 + 0x9d + 0xc5
    MAP(SDLK_ESCAPE,	0x1);
    MAP(SDLK_SPACE,		0x39);
    MAP(SDLK_EXCLAIM,	0x2);	// '1'
    MAP(SDLK_QUOTEDBL,	0x28);	// '''
    MAP(SDLK_HASH,		0x4);	// '3'
    MAP(SDLK_DOLLAR,	0x5);	// '4'
    MAP(37,			0x6);	// '5' <-- where's the keysym SDL guys?
    MAP(SDLK_AMPERSAND,	0x8);	// '7'
    MAP(SDLK_QUOTE,		0x28);	// '''
    MAP(SDLK_LEFTPAREN,	0xa);	// '9'
    MAP(SDLK_RIGHTPAREN,	0xb);	// '0'
    MAP(SDLK_ASTERISK,	0x9);	// '8'
    MAP(SDLK_PLUS,		0xd);	// '='
    MAP(SDLK_COMMA,		0x33);
    MAP(SDLK_MINUS,		0xc);
    MAP(SDLK_PERIOD,	0x34);
    MAP(SDLK_SLASH,		0x35);
    MAP(SDLK_0,		0xb);
    MAP(SDLK_1,		0x2);
    MAP(SDLK_2,		0x3);
    MAP(SDLK_3,		0x4);
    MAP(SDLK_4,		0x5);
    MAP(SDLK_5,		0x6);
    MAP(SDLK_6,		0x7);
    MAP(SDLK_7,		0x8);
    MAP(SDLK_8,		0x9);
    MAP(SDLK_9,		0xa);
    MAP(SDLK_COLON,		0x27);
    MAP(SDLK_SEMICOLON,	0x27);
    MAP(SDLK_LESS,		0x33);
    MAP(SDLK_EQUALS,	0xd);
    MAP(SDLK_GREATER,	0x34);
    MAP(SDLK_QUESTION,	0x35);
    MAP(SDLK_AT,		0x3);	// '2'
    MAP(SDLK_LEFTBRACKET,	0x1a);
    MAP(SDLK_BACKSLASH,	0x2b);
    MAP(SDLK_RIGHTBRACKET,	0x1b);
    MAP(SDLK_CARET,		0x7);	// '7'
    MAP(SDLK_UNDERSCORE,	0xc);
    MAP(SDLK_BACKQUOTE,	0x29);
    MAP(SDLK_a,		0x1e);
    MAP(SDLK_b,		0x30);
    MAP(SDLK_c,		0x2e);
    MAP(SDLK_d,		0x20);
    MAP(SDLK_e,		0x12);
    MAP(SDLK_f,		0x21);
    MAP(SDLK_g,		0x22);
    MAP(SDLK_h,		0x23);
    MAP(SDLK_i,		0x17);
    MAP(SDLK_j,		0x24);
    MAP(SDLK_k,		0x25);
    MAP(SDLK_l,		0x26);
    MAP(SDLK_m,		0x32);
    MAP(SDLK_n,		0x31);
    MAP(SDLK_o,		0x18);
    MAP(SDLK_p,		0x19);
    MAP(SDLK_q,		0x10);
    MAP(SDLK_r,		0x13);
    MAP(SDLK_s,		0x1f);
    MAP(SDLK_t,		0x14);
    MAP(SDLK_u,		0x16);
    MAP(SDLK_v,		0x2f);
    MAP(SDLK_w,		0x11);
    MAP(SDLK_x,		0x2d);
    MAP(SDLK_y,		0x15);
    MAP(SDLK_z,		0x2c);
    MAP(SDLK_DELETE,	0xd3);
    MAP(SDLK_KP0,		0x52);
    MAP(SDLK_KP1,		0x4f);
    MAP(SDLK_KP2,		0x50);
    MAP(SDLK_KP3,		0x51);
    MAP(SDLK_KP4,		0x4b);
    MAP(SDLK_KP5,		0x4c);
    MAP(SDLK_KP6,		0x4d);
    MAP(SDLK_KP7,		0x47);
    MAP(SDLK_KP8,		0x48);
    MAP(SDLK_KP9,		0x49);
    MAP(SDLK_KP_PERIOD,	0x53);
    MAP(SDLK_KP_DIVIDE,	0xb5);
    MAP(SDLK_KP_MULTIPLY,	0x37);
    MAP(SDLK_KP_MINUS,	0x4a);
    MAP(SDLK_KP_PLUS,	0x4e);
    MAP(SDLK_KP_ENTER,	0x9c);
    //MAP(SDLK_KP_EQUALS,	);
    MAP(SDLK_UP,		0xc8);
    MAP(SDLK_DOWN,		0xd0);
    MAP(SDLK_RIGHT,		0xcd);
    MAP(SDLK_LEFT,		0xcb);
    MAP(SDLK_INSERT,	0xd2);
    MAP(SDLK_HOME,		0xc7);
    MAP(SDLK_END,		0xcf);
    MAP(SDLK_PAGEUP,	0xc9);
    MAP(SDLK_PAGEDOWN,	0xd1);
    MAP(SDLK_F1,		0x3b);
    MAP(SDLK_F2,		0x3c);
    MAP(SDLK_F3,		0x3d);
    MAP(SDLK_F4,		0x3e);
    MAP(SDLK_F5,		0x3f);
    MAP(SDLK_F6,		0x40);
    MAP(SDLK_F7,		0x41);
    MAP(SDLK_F8,		0x42);
    MAP(SDLK_F9,		0x43);
    MAP(SDLK_F10,		0x44);
    MAP(SDLK_F11,		0x57);
    MAP(SDLK_F12,		0x58);
    MAP(SDLK_NUMLOCK,	0x45);
    MAP(SDLK_CAPSLOCK,	0x3a);
    MAP(SDLK_SCROLLOCK,	0x46);
    MAP(SDLK_RSHIFT,	0x36);
    MAP(SDLK_LSHIFT,	0x2a);
    MAP(SDLK_RCTRL,		0x9d);
    MAP(SDLK_LCTRL,		0x1d);
    MAP(SDLK_RALT,		0xb8);
    MAP(SDLK_LALT,		0x38);
    MAP(SDLK_LSUPER,	0xdb);	// win l
    MAP(SDLK_RSUPER,	0xdc);	// win r
    MAP(SDLK_PRINT,		-2);	// 0xaa + 0xb7
    MAP(SDLK_SYSREQ,	0x54);	// alt+printscr
    MAP(SDLK_BREAK,		0xb7);	// ctrl+pause
    MAP(SDLK_MENU,		0xdd);	// win menu?
#undef MAP

    return 0;
}

#if defined _WIN32
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#elif defined __linux || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__
# include <sys/mman.h>
#endif

void makeasmwriteable(void)
{
#ifndef ENGINE_USING_A_C
    extern int dep_begin, dep_end;
# if defined _WIN32
    DWORD oldprot;
    if (!VirtualProtect((LPVOID)&dep_begin, (SIZE_T)&dep_end - (SIZE_T)&dep_begin, PAGE_EXECUTE_READWRITE, &oldprot))
    {
        initprint("Error making code writeable\n");
        return;
    }
# elif defined __linux || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__
    int pagesize;
    size_t dep_begin_page;
    pagesize = sysconf(_SC_PAGE_SIZE);
    if (pagesize == -1)
    {
        initprintf("Error getting system page size\n");
        return;
    }
    dep_begin_page = ((size_t)&dep_begin) & ~(pagesize-1);
    if (mprotect((const void *)dep_begin_page, (size_t)&dep_end - dep_begin_page, PROT_READ|PROT_WRITE) < 0)
    {
        initprintf("Error making code writeable (errno=%d)\n", errno);
        return;
    }
# else
#  error Don't know how to unprotect the self-modifying assembly on this platform!
# endif
#endif
}