view src/video/ps2gs/SDL_gsmouse.c @ 4355:9b464226e541 SDL-1.2

Fixed bug #855 Ludwig Nussel 2009-10-18 06:31:52 PDT an mprotect call was added to fix bug 528. However that results in a buffer that allows writing and code execution. Ie the no-execute security features of modern operating systems are defeated this way. Two mprotect calls are needed. One to make the buffer executable but not writeable when done and another one to make the buffer writeable again if the content needs to be changed.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 18 Oct 2009 17:31:37 +0000
parents a1b03ba2fcd0
children
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 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 <sys/ioctl.h>

#include "SDL_mouse.h"
#include "../../events/SDL_events_c.h"
#include "../SDL_cursor_c.h"
#include "SDL_gsvideo.h"
#include "SDL_gsmouse_c.h"


/* The implementation dependent data for the window manager cursor */
struct WMcursor {
	int unused;
};

/* There isn't any implementation dependent data */
void GS_FreeWMCursor(_THIS, WMcursor *cursor)
{
	return;
}

/* There isn't any implementation dependent data */
WMcursor *GS_CreateWMCursor(_THIS,
		Uint8 *data, Uint8 *mask, int w, int h, int hot_x, int hot_y)
{
	return((WMcursor *)0x01);
}

static void GS_MoveCursor(_THIS, SDL_Cursor *cursor, int x, int y)
{
	SDL_Surface *screen;
	struct ps2_image image;
	SDL_Rect area;
	int mouse_y1, mouse_y2;
	void *saved_pixels;
	int screen_updated;

	/* Lock so we don't interrupt an update with mouse motion */
	SDL_LockCursor();

	/* Make sure any pending DMA has completed */
	if ( dma_pending ) {
		ioctl(console_fd, PS2IOC_SENDQCT, 1);
		dma_pending = 0;
	}

	/* Remove the cursor image from the DMA area */
	screen = this->screen;
	saved_pixels = screen->pixels;
	screen->pixels = mapped_mem + screen->offset;
	screen_updated = 0;
	if ( cursor_drawn ) {
		SDL_EraseCursorNoLock(screen);
		cursor_drawn = 0;
		screen_updated = 1;
	}

	/* Save the current mouse area */
	SDL_MouseRect(&area);
	mouse_y1 = area.y;
	mouse_y2 = area.y+area.h;

	/* Only draw the new cursor if there was one passed in */
	if ( cursor ) {
		/* Set the new location */
		cursor->area.x = (x - cursor->hot_x);
		cursor->area.y = (y - cursor->hot_y);

		/* Draw the cursor at the new location */
		if ( (SDL_cursorstate & CURSOR_VISIBLE) && screen->pixels ) {
			SDL_DrawCursorNoLock(screen);
			cursor_drawn = 1;
			screen_updated = 1;
		}
	}
	screen->pixels = saved_pixels;

	/* Update the affected area of the screen */
	if ( screen_updated ) {
		SDL_MouseRect(&area);
		if ( area.y < mouse_y1 ) {
			mouse_y1 = area.y;
		}
		if ( (area.y+area.h) > mouse_y2 ) {
			mouse_y2 = area.y+area.h;
		}
		image = screen_image;
		image.y += screen->offset / screen->pitch + mouse_y1;
		image.h = mouse_y2 - mouse_y1;
		image.ptr = mapped_mem +
		            (image.y - screen_image.y) * screen->pitch;
		ioctl(console_fd, PS2IOC_LOADIMAGE, &image);

		/* Need to scale offscreen image to TV output */
		if ( image.y > 0 ) {
			scaleimage_nonblock(console_fd,
			                    tex_tags_mem, scale_tags_mem);
		}
	}

	/* We're finished */
	SDL_UnlockCursor();
}

void GS_MoveWMCursor(_THIS, int x, int y)
{
	GS_MoveCursor(this, SDL_cursor, x, y);
}

int GS_ShowWMCursor(_THIS, WMcursor *wmcursor)
{
	SDL_Cursor *cursor;
	int x, y;

	/* Draw the cursor at the appropriate location */
	SDL_GetMouseState(&x, &y);
	if ( wmcursor ) {
		cursor = SDL_cursor;
	} else {
		cursor = NULL;
	}
	GS_MoveCursor(this, cursor, x, y);
	return(1);
}