view src/video/x11/SDL_x11wm.c @ 1176:dd2a8deeb26d

Date: Mon, 17 Oct 2005 20:09:03 -0400 From: Mark Schreiber <mark7@alumni.cmu.edu> To: ryan@clutteredmind.org Subject: [PATCH]SDL mprotect() crash fix (I'm going to throw this patch your way at the suggestion of #SDL -- for some reason, I had some difficulty sending it to the main list last time, and I go bonkers subscribing to send each email or patch...) Currently, when I run SDL applications as non-root using SDL_VIDEODRIVER=dga, the fbdev fallback mprotect()s read/write the proper size of mmapped /dev/fb0 (7.5MB), but on framebuffer release mprotect()s read-only the range by the entire size of my video memory (128MB), which causes a segfault: #0 0x002a9a27 in ?? () from /lib/libc.so.6 #1 0x04a63eb6 in SDL_XDGAUnmapFramebuffer (screen=3D0) at XF86DGA2.c:978 #2 0x04a63efc in SDL_XDGACloseFramebuffer (dpy=3D0x9d3f008, screen=3D0) at XF86DGA2.c:268 #3 0x04a68b57 in DGA_Available () at SDL_dgavideo.c:98 #4 0x04a53677 in SDL_VideoInit (driver_name=3D0xbfb0bfc7 "dga", flags=3D0) at SDL_video.c:180 #5 0x04a2613f in SDL_InitSubSystem (flags=3D32) at SDL.c:74 #6 0x04a2617c in SDL_Init (flags=3D32) at SDL.c:166 #7 0x08049722 in main (argc=3D1, argv=3D0x0) at testwin.c:32 This is SDL 1.2.8 on Fedora Core 4, radeon driver for a Radeon 9250, xorg-x11-6.8.2-37. I've attached a one-line patch against SDL CVS that updates the size of the framebuffer at framebuffer map time so that the mprotect() on unmap will be the same size. I'm not sure if this is the best approach (i.e. one might want to retain the original value), but it does make my SDL applications work without segfaulting. -- Best of luck, Mark Schreiber
author Ryan C. Gordon <icculus@icculus.org>
date Sat, 19 Nov 2005 18:57:00 +0000
parents 045f186426e1
children c9b51268668f
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2004 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 <string.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>

#include "SDL_version.h"
#include "SDL_error.h"
#include "SDL_timer.h"
#include "SDL_video.h"
#include "SDL_syswm.h"
#include "SDL_events_c.h"
#include "SDL_pixels_c.h"
#include "SDL_x11modes_c.h"
#include "SDL_x11wm_c.h"

static Uint8 reverse_byte(Uint8 x)
{
	x = (x & 0xaa) >> 1 | (x & 0x55) << 1;
	x = (x & 0xcc) >> 2 | (x & 0x33) << 2;
	x = (x & 0xf0) >> 4 | (x & 0x0f) << 4;
	return x;
}

void X11_SetIcon(_THIS, SDL_Surface *icon, Uint8 *mask)
{
	SDL_Surface *sicon;
	XWMHints *wmhints;
	XImage *icon_image;
	Pixmap icon_pixmap;
	Pixmap mask_pixmap;
	Window icon_window = None;
	GC gc;
	XGCValues GCvalues;
	int i, dbpp;
	SDL_Rect bounds;
	Uint8 *LSBmask;
	Visual *dvis;
	char *p;
	int masksize;

	SDL_Lock_EventThread();

	/* The icon must use the default visual, depth and colormap of the
	   screen, so it might need a conversion */
	dvis = DefaultVisual(SDL_Display, SDL_Screen);
	dbpp = DefaultDepth(SDL_Display, SDL_Screen);
	for(i = 0; i < this->hidden->nvisuals; i++) {
		if(this->hidden->visuals[i].visual == dvis) {
			dbpp = this->hidden->visuals[i].bpp;
			break;
		}
	}

	/* The Visual struct is supposed to be opaque but we cheat a little */
	sicon = SDL_CreateRGBSurface(SDL_SWSURFACE, icon->w, icon->h,
				     dbpp,
				     dvis->red_mask, dvis->green_mask,
				     dvis->blue_mask, 0);
	if ( sicon == NULL )
		goto done;

	if(dbpp == 8) {
		/* Default visual is 8bit; we need to allocate colours from
		   the default colormap */
		SDL_Color want[256], got[256];
		int nwant;
		Colormap dcmap;
		int missing;
		dcmap = DefaultColormap(SDL_Display, SDL_Screen);
		if(icon->format->palette) {
			/* The icon has a palette as well - we just have to
			   find those colours */
			nwant = icon->format->palette->ncolors;
			memcpy(want, icon->format->palette->colors,
			       nwant * sizeof want[0]);
		} else {
			/* try the standard 6x6x6 cube for lack of better
			   ideas */
			int r, g, b, i;
			for(r = i = 0; r < 256; r += 0x33)
				for(g = 0; g < 256; g += 0x33)
					for(b = 0; b < 256; b += 0x33, i++) {
						want[i].r = r;
						want[i].g = g;
						want[i].b = b;
					}
			nwant = 216;
		}
		if(SDL_iconcolors) {
			/* free already allocated colours first */
			unsigned long freelist[512];
			int nfree = 0;
			for(i = 0; i < 256; i++) {
				while(SDL_iconcolors[i]) {
					freelist[nfree++] = i;
					SDL_iconcolors[i]--;
				}
			}
			pXFreeColors(GFX_Display, dcmap, freelist, nfree, 0);
		}
		if(!SDL_iconcolors)
			SDL_iconcolors = malloc(256 * sizeof *SDL_iconcolors);
		memset(SDL_iconcolors, 0, 256 * sizeof *SDL_iconcolors);

		/* try to allocate the colours */
		memset(got, 0, sizeof got);
		missing = 0;
		for(i = 0; i < nwant; i++) {
			XColor c;
			c.red = want[i].r << 8;
			c.green = want[i].g << 8;
			c.blue = want[i].b << 8;
			c.flags = DoRed | DoGreen | DoBlue;
			if(pXAllocColor(GFX_Display, dcmap, &c)) {
				/* got the colour */
				SDL_iconcolors[c.pixel]++;
				got[c.pixel] = want[i];
			} else {
				missing = 1;
			}
		}
		if(missing) {
			/* Some colours were apparently missing, so we just
			   allocate all the rest as well */
			XColor cols[256];
			for(i = 0; i < 256; i++)
				cols[i].pixel = i;
			pXQueryColors(GFX_Display, dcmap, cols, 256);
			for(i = 0; i < 256; i++) {
				got[i].r = cols[i].red >> 8;
				got[i].g = cols[i].green >> 8;
				got[i].b = cols[i].blue >> 8;
				if(!SDL_iconcolors[i]) {
					if(pXAllocColor(GFX_Display, dcmap,
							cols + i)) {
						SDL_iconcolors[i] = 1;
					} else {
						/* index not available */
						got[i].r = 0;
						got[i].g = 0;
						got[i].b = 0;
					}
				}
			}
		}

		SDL_SetColors(sicon, got, 0, 256);
	}

	bounds.x = 0;
	bounds.y = 0;
	bounds.w = icon->w;
	bounds.h = icon->h;
	if ( SDL_LowerBlit(icon, &bounds, sicon, &bounds) < 0 )
		goto done;

	/* We need the mask as given, except in LSBfirst format instead of
	   MSBfirst. Reverse the bits in each byte. */
	masksize = ((sicon->w + 7) >> 3) * sicon->h;
	LSBmask = malloc(masksize);
	if ( LSBmask == NULL ) {
		goto done;
	}
	memset(LSBmask, 0, masksize);
	for(i = 0; i < masksize; i++)
		LSBmask[i] = reverse_byte(mask[i]);
	mask_pixmap = pXCreatePixmapFromBitmapData(SDL_Display, WMwindow,
						  (char *)LSBmask,
						  sicon->w, sicon->h,
						  1L, 0L, 1);

	/* Transfer the image to an X11 pixmap */
	icon_image = pXCreateImage(SDL_Display,
				  DefaultVisual(SDL_Display, SDL_Screen),
				  DefaultDepth(SDL_Display, SDL_Screen),
				  ZPixmap, 0, sicon->pixels,
				  sicon->w, sicon->h,
				  32, 0);
	icon_image->byte_order = (SDL_BYTEORDER == SDL_BIG_ENDIAN)
		                 ? MSBFirst : LSBFirst;
	icon_pixmap = pXCreatePixmap(SDL_Display, SDL_Root, sicon->w, sicon->h,
				    DefaultDepth(SDL_Display, SDL_Screen));
	gc = pXCreateGC(SDL_Display, icon_pixmap, 0, &GCvalues);
	pXPutImage(SDL_Display, icon_pixmap, gc, icon_image,
		  0, 0, 0, 0, sicon->w, sicon->h);
	pXFreeGC(SDL_Display, gc);
	pXDestroyImage(icon_image);
	free(LSBmask);
	sicon->pixels = NULL;

	/* Some buggy window managers (some versions of Enlightenment, it
	   seems) need an icon window *and* icon pixmap to work properly, while
	   it screws up others. The default is only to use a pixmap. */
	p = getenv("SDL_VIDEO_X11_ICONWIN");
	if(p && *p) {
		icon_window = pXCreateSimpleWindow(SDL_Display, SDL_Root,
						  0, 0, sicon->w, sicon->h, 0,
						  CopyFromParent,
						  CopyFromParent);
		pXSetWindowBackgroundPixmap(SDL_Display, icon_window,
					   icon_pixmap);
		pXClearWindow(SDL_Display, icon_window);
	}

	/* Set the window icon to the icon pixmap (and icon window) */
	wmhints = pXAllocWMHints();
	wmhints->flags = (IconPixmapHint | IconMaskHint);
	wmhints->icon_pixmap = icon_pixmap;
	wmhints->icon_mask = mask_pixmap;
	if(icon_window != None) {
		wmhints->flags |= IconWindowHint;
		wmhints->icon_window = icon_window;
	}
	pXSetWMHints(SDL_Display, WMwindow, wmhints);
	pXFree(wmhints);
	pXSync(SDL_Display, False);

  done:
	SDL_Unlock_EventThread();
	SDL_FreeSurface(sicon);
}

void X11_SetCaption(_THIS, const char *title, const char *icon)
{
	XTextProperty titleprop, iconprop;

	/* Lock the event thread, in multi-threading environments */
	SDL_Lock_EventThread();

	if ( title != NULL ) {
		int error = XLocaleNotSupported;
#ifdef X_HAVE_UTF8_STRING
		error = pXutf8TextListToTextProperty(SDL_Display,
				(char **)&title, 1, XUTF8StringStyle,
				&titleprop);
#endif
		if ( error != Success ) {
			pXStringListToTextProperty((char **)&title, 1,
					&titleprop);
		}
		pXSetWMName(SDL_Display, WMwindow, &titleprop);
		pXFree(titleprop.value);
	}
	if ( icon != NULL ) {
		int error = XLocaleNotSupported;
#ifdef X_HAVE_UTF8_STRING
		error = pXutf8TextListToTextProperty(SDL_Display,
				(char **)&icon, 1, XUTF8StringStyle, &iconprop);
#endif
		if ( error != Success ) {
			pXStringListToTextProperty((char **)&icon, 1, &iconprop);
		}
		pXSetWMIconName(SDL_Display, WMwindow, &iconprop);
		pXFree(iconprop.value);
	}
	pXSync(SDL_Display, False);

	SDL_Unlock_EventThread();
}

/* Iconify the window */
int X11_IconifyWindow(_THIS)
{
	int result;

	SDL_Lock_EventThread();
	result = pXIconifyWindow(SDL_Display, WMwindow, SDL_Screen);
	pXSync(SDL_Display, False);
	SDL_Unlock_EventThread();
	return(result);
}

SDL_GrabMode X11_GrabInputNoLock(_THIS, SDL_GrabMode mode)
{
	int result;

	if ( this->screen == NULL ) {
		return(SDL_GRAB_OFF);
	}
	if ( ! SDL_Window ) {
		return(mode);	/* Will be set later on mode switch */
	}
	if ( mode == SDL_GRAB_OFF ) {
		pXUngrabPointer(SDL_Display, CurrentTime);
		pXUngrabKeyboard(SDL_Display, CurrentTime);
	} else {
		if ( this->screen->flags & SDL_FULLSCREEN ) {
			/* Unbind the mouse from the fullscreen window */
			pXUngrabPointer(SDL_Display, CurrentTime);
		}
		/* Try to grab the mouse */
#if 0 /* We'll wait here until we actually grab, otherwise behavior undefined */
		for ( numtries = 0; numtries < 10; ++numtries ) {
#else
		while ( 1 ) {
#endif
			result = pXGrabPointer(SDL_Display, SDL_Window, True, 0,
						GrabModeAsync, GrabModeAsync,
						SDL_Window, None, CurrentTime);
			if ( result == GrabSuccess ) {
				break;
			}
			SDL_Delay(100);
		}
		if ( result != GrabSuccess ) {
			/* Uh, oh, what do we do here? */ ;
		}
		/* Now grab the keyboard */
		pXGrabKeyboard(SDL_Display, WMwindow, True,
				GrabModeAsync, GrabModeAsync, CurrentTime);

		/* Raise the window if we grab the mouse */
		if ( !(this->screen->flags & SDL_FULLSCREEN) )
			pXRaiseWindow(SDL_Display, WMwindow);

		/* Make sure we register input focus */
		SDL_PrivateAppActive(1, SDL_APPINPUTFOCUS);
	}
	pXSync(SDL_Display, False);

	return(mode);
}

SDL_GrabMode X11_GrabInput(_THIS, SDL_GrabMode mode)
{
	SDL_Lock_EventThread();
	mode = X11_GrabInputNoLock(this, mode);
	SDL_Unlock_EventThread();

	return(mode);
}

/* If 'info' is the right version, this function fills it and returns 1.
   Otherwise, in case of a version mismatch, it returns -1.
*/
static void lock_display(void)
{
	SDL_Lock_EventThread();
}
static void unlock_display(void)
{
	/* Make sure any X11 transactions are completed */
	SDL_VideoDevice *this = current_video;
	pXSync(SDL_Display, False);
	SDL_Unlock_EventThread();
}
int X11_GetWMInfo(_THIS, SDL_SysWMinfo *info)
{
	if ( info->version.major <= SDL_MAJOR_VERSION ) {
		info->subsystem = SDL_SYSWM_X11;
		info->info.x11.display = SDL_Display;
		info->info.x11.window = SDL_Window;
		if ( SDL_VERSIONNUM(info->version.major,
		                    info->version.minor,
		                    info->version.patch) >= 1002 ) {
			info->info.x11.fswindow = FSwindow;
			info->info.x11.wmwindow = WMwindow;
		}
		info->info.x11.lock_func = lock_display;
		info->info.x11.unlock_func = unlock_display;
		return(1);
	} else {
		SDL_SetError("Application not compiled with SDL %d.%d\n",
					SDL_MAJOR_VERSION, SDL_MINOR_VERSION);
		return(-1);
	}
}