view src/video/bwindow/SDL_BWin.h @ 4158:96ce26f24b01 SDL-1.2

Date: Sun, 7 Sep 2008 15:17:00 +0200 From: c2woody@gmx.net Subject: [SDL] SDL 1.2 doube free/pointer zeroing missing Hello, this is about a crash/debug breakage for the current SDL 1.2 source tree (today's svn checkout, same problem in 1.2.13 and before as far as relevant). In some places memory is free()d but the associated pointer is not zeroed, leading to for example double free()s. For me this happened because SDL_StopEventThread() was executed twice (during restart of the subsystems), once for the close down in SDL_VideoQuit() and once at the startup, right at the beginning of SDL_StartEventLoop(). Thus the code SDL_DestroyMutex(SDL_EventQ.lock); (see SDL_events.c) was called twice and executed the SDL_free(mutex); twice as well, leading to a crash (msvc 64bit for which it was noticed). I've tried to check all other occurrences of SDL_free and similar code in msvc, see the attached patch (udiff against revision 4082). Non-windows only codepaths have neither been checked nor touched. Comments/ideas welcome. Attached patch: NULLifies some pointers after they have been free()d.
author Sam Lantinga <slouken@libsdl.org>
date Wed, 12 Nov 2008 17:23:40 +0000
parents 5804139bdf0b
children a1b03ba2fcd0
line wrap: on
line source

/*
    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
*/

#ifndef _SDL_BWin_h
#define _SDL_BWin_h

#include "SDL_config.h"

#include <stdio.h>
#include <AppKit.h>
#include <InterfaceKit.h>
#include <be/game/DirectWindow.h>
#if SDL_VIDEO_OPENGL
#include <be/opengl/GLView.h>
#endif
#include <support/UTF8.h>

#include "../../main/beos/SDL_BeApp.h"
#include "SDL_events.h"
#include "SDL_BView.h"

extern "C" {
#include "../../events/SDL_events_c.h"

extern int mouse_relative;
};

class SDL_BWin : public BDirectWindow
{
public:
	SDL_BWin(BRect bounds) :
			BDirectWindow(bounds, "Untitled", B_TITLED_WINDOW, 0) {
		last_buttons = 0;
		the_view = NULL;
#if SDL_VIDEO_OPENGL
		SDL_GLView = NULL;
#endif
		SDL_View = NULL;
		Unlock();
		shown = false;
		inhibit_resize = false;
	}

	virtual ~SDL_BWin() {
		Lock();
		if ( the_view ) {
#if SDL_VIDEO_OPENGL
			if ( the_view == SDL_GLView ) {
				SDL_GLView->UnlockGL();
			}
#endif
			RemoveChild(the_view);
			the_view = NULL;
		}
		Unlock();
#if SDL_VIDEO_OPENGL
		if ( SDL_GLView ) {
			delete SDL_GLView;
		}
#endif
		if ( SDL_View ) {
			delete SDL_View;
		}
	}
	

	/* Override the Show() method so we can tell when we've been shown */
	virtual void Show(void) {
		BWindow::Show();
		shown = true;
	}
	virtual bool Shown(void) {
		return (shown);
	}
	/* If called, the next resize event will not be forwarded to SDL. */
	virtual void InhibitResize(void) {
		inhibit_resize=true;
	}
	/* Handle resizing of the window */
	virtual void FrameResized(float width, float height) {
		if(inhibit_resize)
			inhibit_resize = false;
		else 
			SDL_PrivateResize((int)width, (int)height);
	}
	virtual int CreateView(Uint32 flags, Uint32 gl_flags) {
		int retval;

		retval = 0;
		Lock();
		if ( flags & SDL_OPENGL ) {
#if SDL_VIDEO_OPENGL
			if ( SDL_GLView == NULL ) {
				SDL_GLView = new BGLView(Bounds(), "SDL GLView",
					 	B_FOLLOW_ALL_SIDES, (B_WILL_DRAW|B_FRAME_EVENTS),
					 	gl_flags);
				SDL_GLView->EnableDirectMode(true);
			}
			if ( the_view != SDL_GLView ) {
				if ( the_view ) {
					RemoveChild(the_view);
				}
				AddChild(SDL_GLView);
				SDL_GLView->LockGL();
				the_view = SDL_GLView;
			}
#else
			SDL_SetError("OpenGL support not enabled");
			retval = -1;
#endif
		} else {
			if ( SDL_View == NULL ) {
				SDL_View = new SDL_BView(Bounds());
			}
			if ( the_view != SDL_View ) {
				if ( the_view ) {
#if SDL_VIDEO_OPENGL
					if ( the_view == SDL_GLView ) {
						SDL_GLView->UnlockGL();
					}
#endif
					RemoveChild(the_view);
				}
				AddChild(SDL_View);
				the_view = SDL_View;
			}
		}
		Unlock();
		return(retval);
	}
	virtual void SetBitmap(BBitmap *bitmap) {
		SDL_View->SetBitmap(bitmap);
	}
	virtual void SetXYOffset(int x, int y) {
#if SDL_VIDEO_OPENGL
		if ( the_view == SDL_GLView ) {
			return;
		}
#endif
		SDL_View->SetXYOffset(x, y);
	}
	virtual void GetXYOffset(int &x, int &y) {
#if SDL_VIDEO_OPENGL
		if ( the_view == SDL_GLView ) {
			x = 0;
			y = 0;
			return;
		}
#endif
		SDL_View->GetXYOffset(x, y);
	}
	virtual void GetXYOffset(float &x, float &y) {
#if SDL_VIDEO_OPENGL
		if ( the_view == SDL_GLView ) {
			x = 0.0f;
			y = 0.0f;
			return;
		}
#endif
		SDL_View->GetXYOffset(x, y);
	}
	virtual bool BeginDraw(void) {
		return(Lock());
	}
	virtual void DrawAsync(BRect updateRect) {
		SDL_View->DrawAsync(updateRect);
	}
	virtual void EndDraw(void) {
		SDL_View->Sync();
		Unlock();
	}
#if SDL_VIDEO_OPENGL
	virtual void SwapBuffers(void) {
		SDL_GLView->UnlockGL();
		SDL_GLView->LockGL();
		SDL_GLView->SwapBuffers();
	}
#endif
	virtual BView *View(void) {
		return(the_view);
	}

	/* Hook functions -- overridden */
	virtual void Minimize(bool minimize) {
		/* This is only called when mimimized, not when restored */
		//SDL_PrivateAppActive(minimize, SDL_APPACTIVE);
		BWindow::Minimize(minimize);
	}
	virtual void WindowActivated(bool active) {
		SDL_PrivateAppActive(active, SDL_APPINPUTFOCUS);
	}
	virtual bool QuitRequested(void) {
		if ( SDL_BeAppActive > 0 ) {
			SDL_PrivateQuit();
			/* We don't ever actually close the window here because
			   the application should respond to the quit request,
			   or ignore it as desired.
			 */
			return(false);
		}
		return(true);	/* Close the app window */
	}
	virtual void Quit() {
		if (!IsLocked())
			Lock();
		BDirectWindow::Quit();
	}

	virtual int16 Translate2Unicode(const char *buf) {
		int32 state, srclen, dstlen;
		unsigned char destbuf[2];
		Uint16 unicode = 0;

		if ((uchar)buf[0] > 127) {
			state = 0;
			srclen = SDL_strlen(buf);
			dstlen = sizeof(destbuf);
			convert_from_utf8(B_UNICODE_CONVERSION, buf, &srclen, (char *)destbuf, &dstlen, &state);
			unicode = destbuf[0];
			unicode <<= 8;
			unicode |= destbuf[1];
		} else
			unicode = buf[0];

		/* For some reason function keys map to control characters */
# define CTRL(X)	((X)-'@')
		switch (unicode) {
		    case CTRL('A'):
		    case CTRL('B'):
		    case CTRL('C'):
		    case CTRL('D'):
		    case CTRL('E'):
		    case CTRL('K'):
		    case CTRL('L'):
		    case CTRL('P'):
			if ( ! (SDL_GetModState() & KMOD_CTRL) )
				unicode = 0;
			break;
			/* Keyboard input maps newline to carriage return */
			case '\n':
				unicode = '\r';
			break;
		    default:
			break;
		}

		return unicode;
	}

	virtual void DispatchMessage(BMessage *msg, BHandler *target);

private:
#if SDL_VIDEO_OPENGL
	BGLView *SDL_GLView;
#endif
	SDL_BView *SDL_View;
	BView *the_view;
	bool shown;
	bool inhibit_resize;
	int32 last_buttons;
};

#endif /* _SDL_BWin_h */