view src/video/x11/SDL_x11image.c @ 3957:b1d5b56aa549 SDL-1.2

Date: Mon, 4 Jun 2007 06:17:59 +0000 (UTC) From: George Gensure <werkt0@gmail.com> Subject: [SDL] error removal patch for SDL_x11dyn.c I found that calling SDL_GetError when an error hasn't necessarily occurred is still reporting problems from loadso regarding dynamic functions in X11. I've added the following to my local copy to avoid revealing the 'many library lookup' approach adopted by x11dyn.c:
author Ryan C. Gordon <icculus@icculus.org>
date Wed, 13 Jun 2007 07:54:10 +0000
parents 3ba88cb7eb1b
children e49147870aac c121d94672cb a1b03ba2fcd0
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

#include <stdio.h>
#include <unistd.h>

#include "SDL_endian.h"
#include "../../events/SDL_events_c.h"
#include "SDL_x11image_c.h"

#ifndef NO_SHARED_MEMORY

/* 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 = True;
        	return(0);
        } else
		return(X_handler(d,e));
}

static void try_mitshm(_THIS, SDL_Surface *screen)
{
	/* Dynamic X11 may not have SHM entry points on this box. */
	if ((use_mitshm) && (!SDL_X11_HAVE_SHM))
		use_mitshm = 0;

	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;
	}
	if(!use_mitshm)
#endif /* not NO_SHARED_MEMORY */
	{
		int bpp;
		screen->pixels = SDL_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 (SDL_memcmp(line, "cpu", 3) == 0 && line[3] != ' ') {
                       ++num_cpus;
                   }
               }
               fclose(pstat);
           }
#elif defined(__IRIX__)
	   num_cpus = sysconf(_SC_NPROC_ONLN);
#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);
}