/*

SDL - Simple DirectMedia Layer

Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Library General Public

License as published by the Free Software Foundation; either

version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Library General Public License for more details.

You should have received a copy of the GNU Library General Public

License along with this library; if not, write to the Free

Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Sam Lantinga

slouken@libsdl.org

*/

#ifdef SAVE_RCSID

static char rcsid =

"@(#) $Id$";

#endif

#include <stdlib.h>

#include <unistd.h>

#include "SDL_error.h"

#include "SDL_endian.h"

#include "SDL_events_c.h"

#include "SDL_x11image_c.h"

#ifndef NO_SHARED_MEMORY

/* Shared memory information */

extern int XShmQueryExtension(Display *dpy); /* Not in X11 headers */

/* Shared memory error handler routine */

static int shm_error;

static int (*X_handler)(Display *, XErrorEvent *) = NULL;

static int shm_errhandler(Display *d, XErrorEvent *e)

{

if ( e->error_code == BadAccess ) {

shm_error = 1;

return(0);

} else

return(X_handler(d,e));

}

static void try_mitshm(_THIS, SDL_Surface *screen)

{

if(!use_mitshm)

return;

shminfo.shmid = shmget(IPC_PRIVATE, screen->h*screen->pitch,

IPC_CREAT | 0777);

if ( shminfo.shmid >= 0 ) {

shminfo.shmaddr = (char *)shmat(shminfo.shmid, 0, 0);

shminfo.readOnly = False;

if ( shminfo.shmaddr != (char *)-1 ) {

shm_error = False;

X_handler = XSetErrorHandler(shm_errhandler);

XShmAttach(SDL_Display, &shminfo);

XSync(SDL_Display, True);

XSetErrorHandler(X_handler);

if (shm_error)

shmdt(shminfo.shmaddr);

} else {

shm_error = True;

}

shmctl(shminfo.shmid, IPC_RMID, NULL);

} else {

shm_error = True;

}

if ( shm_error )

use_mitshm = 0;

if ( use_mitshm )

screen->pixels = shminfo.shmaddr;

}

#endif /* ! NO_SHARED_MEMORY */

/* Various screen update functions available */

static void X11_NormalUpdate(_THIS, int numrects, SDL_Rect *rects);

static void X11_MITSHMUpdate(_THIS, int numrects, SDL_Rect *rects);

int X11_SetupImage(_THIS, SDL_Surface *screen)

{

#ifndef NO_SHARED_MEMORY

try_mitshm(this, screen);

if(use_mitshm) {

SDL_Ximage = XShmCreateImage(SDL_Display, SDL_Visual,

this->hidden->depth, ZPixmap,

shminfo.shmaddr, &shminfo,

screen->w, screen->h);

if(!SDL_Ximage) {

XShmDetach(SDL_Display, &shminfo);

XSync(SDL_Display, False);

shmdt(shminfo.shmaddr);

screen->pixels = NULL;

goto error;

}

this->UpdateRects = X11_MITSHMUpdate;

}

#endif /* not NO_SHARED_MEMORY */

if(!use_mitshm) {

int bpp;

screen->pixels = malloc(screen->h*screen->pitch);

if ( screen->pixels == NULL ) {

SDL_OutOfMemory();

return -1;

}

bpp = screen->format->BytesPerPixel;

SDL_Ximage = XCreateImage(SDL_Display, SDL_Visual,

this->hidden->depth, ZPixmap, 0,

(char *)screen->pixels,

screen->w, screen->h,

32, 0);

if ( SDL_Ximage == NULL )

goto error;

/* XPutImage will convert byte sex automatically */

SDL_Ximage->byte_order = (SDL_BYTEORDER == SDL_BIG_ENDIAN)

? MSBFirst : LSBFirst;

this->UpdateRects = X11_NormalUpdate;

}

screen->pitch = SDL_Ximage->bytes_per_line;

return(0);

error:

SDL_SetError("Couldn't create XImage");

return 1;

}

void X11_DestroyImage(_THIS, SDL_Surface *screen)

{

if ( SDL_Ximage ) {

XDestroyImage(SDL_Ximage);

#ifndef NO_SHARED_MEMORY

if ( use_mitshm ) {

XShmDetach(SDL_Display, &shminfo);

XSync(SDL_Display, False);

shmdt(shminfo.shmaddr);

}

#endif /* ! NO_SHARED_MEMORY */

SDL_Ximage = NULL;

}

if ( screen ) {

screen->pixels = NULL;

}

}

/* Determine the number of CPUs in the system */

static int num_CPU(void)

{

static int num_cpus = 0;

if(!num_cpus) {

#if defined(__linux)

char line[BUFSIZ];

FILE *pstat = fopen("/proc/stat", "r");

if ( pstat ) {

while ( fgets(line, sizeof(line), pstat) ) {

if (memcmp(line, "cpu", 3) == 0 && line[3] != ' ') {

++num_cpus;

}

}

fclose(pstat);

}

#elif defined(_SC_NPROCESSORS_ONLN)

/* number of processors online (SVR4.0MP compliant machines) */

num_cpus = sysconf(_SC_NPROCESSORS_ONLN);

#elif defined(_SC_NPROCESSORS_CONF)

/* number of processors configured (SVR4.0MP compliant machines) */

num_cpus = sysconf(_SC_NPROCESSORS_CONF);

#endif

if ( num_cpus <= 0 ) {

num_cpus = 1;

}

}

return num_cpus;

}

int X11_ResizeImage(_THIS, SDL_Surface *screen, Uint32 flags)

{

int retval;

X11_DestroyImage(this, screen);

if ( flags & SDL_OPENGL ) { /* No image when using GL */

retval = 0;

} else {

retval = X11_SetupImage(this, screen);

/* We support asynchronous blitting on the display */

if ( flags & SDL_ASYNCBLIT ) {

/* This is actually slower on single-CPU systems,

probably because of CPU contention between the

X server and the application.

Note: Is this still true with XFree86 4.0?

*/

if ( num_CPU() > 1 ) {

screen->flags |= SDL_ASYNCBLIT;

}

}

}

return(retval);

}

/* We don't actually allow hardware surfaces other than the main one */

int X11_AllocHWSurface(_THIS, SDL_Surface *surface)

{

return(-1);

}

void X11_FreeHWSurface(_THIS, SDL_Surface *surface)

{

return;

}

int X11_LockHWSurface(_THIS, SDL_Surface *surface)

{

if ( (surface == SDL_VideoSurface) && blit_queued ) {

XSync(GFX_Display, False);

blit_queued = 0;

}

return(0);

}

void X11_UnlockHWSurface(_THIS, SDL_Surface *surface)

{

return;

}

int X11_FlipHWSurface(_THIS, SDL_Surface *surface)

{

return(0);

}

static void X11_NormalUpdate(_THIS, int numrects, SDL_Rect *rects)

{

int i;

for (i = 0; i < numrects; ++i) {

if ( rects[i].w == 0 || rects[i].h == 0 ) { /* Clipped? */

continue;

}

XPutImage(GFX_Display, SDL_Window, SDL_GC, SDL_Ximage,

rects[i].x, rects[i].y,

rects[i].x, rects[i].y, rects[i].w, rects[i].h);

}

if ( SDL_VideoSurface->flags & SDL_ASYNCBLIT ) {

XFlush(GFX_Display);

blit_queued = 1;

} else {

XSync(GFX_Display, False);

}

}

static void X11_MITSHMUpdate(_THIS, int numrects, SDL_Rect *rects)

{

#ifndef NO_SHARED_MEMORY

int i;

for ( i=0; i<numrects; ++i ) {

if ( rects[i].w == 0 || rects[i].h == 0 ) { /* Clipped? */

continue;

}

XShmPutImage(GFX_Display, SDL_Window, SDL_GC, SDL_Ximage,

rects[i].x, rects[i].y,

rects[i].x, rects[i].y, rects[i].w, rects[i].h,

False);

}

if ( SDL_VideoSurface->flags & SDL_ASYNCBLIT ) {

XFlush(GFX_Display);

blit_queued = 1;

} else {

XSync(GFX_Display, False);

}

#endif /* ! NO_SHARED_MEMORY */

}

/* There's a problem with the automatic refreshing of the display.

Even though the XVideo code uses the GFX_Display to update the

video memory, it appears that updating the window asynchronously

from a different thread will cause "blackouts" of the window.

This is a sort of a hacked workaround for the problem.

*/

static int enable_autorefresh = 1;

void X11_DisableAutoRefresh(_THIS)

{

--enable_autorefresh;

}

void X11_EnableAutoRefresh(_THIS)

{

++enable_autorefresh;

}

void X11_RefreshDisplay(_THIS)

{

/* Don't refresh a display that doesn't have an image (like GL)

Instead, post an expose event so the application can refresh.

*/

if ( ! SDL_Ximage || (enable_autorefresh <= 0) ) {

SDL_PrivateExpose();

return;

}

#ifndef NO_SHARED_MEMORY

if ( this->UpdateRects == X11_MITSHMUpdate ) {

XShmPutImage(SDL_Display, SDL_Window, SDL_GC, SDL_Ximage,

0, 0, 0, 0, this->screen->w, this->screen->h,

False);

} else

#endif /* ! NO_SHARED_MEMORY */

{

XPutImage(SDL_Display, SDL_Window, SDL_GC, SDL_Ximage,

0, 0, 0, 0, this->screen->w, this->screen->h);

}

XSync(SDL_Display, False);

}