Re: [PATCH] Remove potential reference count races.

[Nikolay Sivov]

On 10/28/2012 04:59, [e-mail] wrote:
> From: Max TenEyck Woodbury
>
> dlls/gdi32/freetype.c |    4 ++--
>   1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/dlls/gdi32/freetype.c b/dlls/gdi32/freetype.c
> index 6af977c..3379c6e 100644
> --- a/dlls/gdi32/freetype.c
> +++ b/dlls/gdi32/freetype.c
> @@ -3820,7 +3820,7 @@ static struct font_mapping *map_font_file( const char *name )
>       {
>           if (mapping->dev == st.st_dev && mapping->ino == st.st_ino)
>           {
> -
>        mapping->refcount++;
> -
>        InterlockedIncrement(&mapping->refcount);
>         close( fd );
>         return mapping;
>     }
>
> @@ -3850,7 +3850,7 @@ error:
>
> static void unmap_font_file( struct font_mapping *mapping )
>   {
> - if (!--mapping->refcount)
> - if (!InterlockedDecrement(&mapping->refcount))
>  {
>      list_remove( &mapping->entry );
>      munmap( mapping->data, mapping->size );

How does it help exactly and what is the problem with this code?