[Emacs-bug-tracker] bug#8410: closed (make_invisible_cursor returns garbage if XCreateBitmapFromData fails)

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Your message dated Tue, 05 Apr 2011 22:47:16 -0700
with message-id <address@hidden>
and subject line fix installed in trunk
has caused the GNU bug report #8410,
regarding make_invisible_cursor returns garbage if XCreateBitmapFromData fails
to be marked as done.

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-- 
8410: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8410
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> --- Begin Message ---
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> Subject: 
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> make_invisible_cursor returns garbage if XCreateBitmapFromData fails
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> Date: 
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> Fri, 01 Apr 2011 19:21:34 -0700
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> User-agent: 
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> Mozilla/5.0 (X11; U; Linux i686; en-US;	rv:1.9.2.14) Gecko/20110223 Thunderbird/3.1.8
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> I found this bug via static analysis, using GCC 4.6.0's warnings.
> src/xfns.c's make_invisible_cursor returns a garbage value if
> XCreateBitmapFromData fails.  I plan to fix it as follows.
> I don't know that returning 0 fixes the bug, so I'd like someone
> who's expert in this area to look at this.  Since the patch replaces
> undefined behavior with defined behavior it isn't likely to be
> introducing a bug, so it shouldn't hurt to install the patch.
>
> * xfns.c (make_invisible_cursor): Don't return garbage
> if XCreateBitmapFromData fails.
> === modified file 'src/xfns.c'
> --- src/xfns.c  2011-04-01 20:30:45 +0000
> +++ src/xfns.c  2011-04-01 23:01:33 +0000
> @@ -855,19 +855,20 @@
>    static char const no_data[] = { 0 };
>    Pixmap pix;
>    XColor col;
> -  Cursor c;
> +  Cursor c = 0;
>
>    x_catch_errors (dpy);
>    pix = XCreateBitmapFromData (dpy, FRAME_X_DISPLAY_INFO (f)->root_window,
>                                 no_data, 1, 1);
>    if (! x_had_errors_p (dpy) && pix != None)
>      {
> +      Cursor pixc;
>        col.pixel = 0;
>        col.red = col.green = col.blue = 0;
>        col.flags = DoRed | DoGreen | DoBlue;
> -      c = XCreatePixmapCursor (dpy, pix, pix, &col, &col, 0, 0);
> -      if (x_had_errors_p (dpy) || c == None)
> -        c = 0;
> +      pixc = XCreatePixmapCursor (dpy, pix, pix, &col, &col, 0, 0);
> +      if (! x_had_errors_p (dpy) && pixc != None)
> +        c = pixc;
>        XFreePixmap (dpy, pix);
>      }
>
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> --- End Message ---
> --- Begin Message ---
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>
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> Subject: 
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> fix installed in trunk
>
>
>
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> Date: 
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> Tue, 05 Apr 2011 22:47:16 -0700
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>
>
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> User-agent: 
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> Mozilla/5.0 (X11; U; Linux i686; en-US;	rv:1.9.2.14) Gecko/20110223 Thunderbird/3.1.8
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>
>
>
> I committed the previously-mentioned fix
> as part of the merge to the trunk in bzr 103841.
>
>
> --- End Message ---