[Freeciv-Dev] Re: another cma-crash (PR#1888)

[Raimar Falke <rf13@xxxxxxxxxxxxxxxxx>]

On Wed, Aug 07, 2002 at 02:57:52AM -0700, Raimar Falke wrote:
> On Wed, Aug 07, 2002 at 12:53:06AM +0300, Jussi Asp wrote:
> > Hi,
> > 
> > Here's an another crash it got today, with latest cvs-version.
> > included a savegame which caused the crash. join as haakon vii and ivan 
> > the terrible and take haakon empty city with ivan's unit. city had max 
> > food cma on.
> > I hope you find the bug, using cma is so much more fun than without it. :)
> 
> Analysis:
> 
> new owner                               server                                
>        old owner
>  - client sends move request
>                                         - server sends a city_info packet 
> with an
>                                           updated city_map (because of the 
> enemy 
>                                           unit)
>                                         - server transfers city to new owner
>                                         - server sends a city_info packet 
> with the 
>                                           new owner to the old owner
>                                                                               
>       - receives the first city_info packet
>                                                                               
>       - handle_city is called
>                                                                               
>       - CMA calculates
>                                                                               
>       - CMA want to apply the new allocation 
>                                                                               
>         at the server
>                                                                               
>       - sends the changes to the server
>                                                                               
>       - wait for the results
>                                                                               
>         - receives the second city_info packet
>                                                                               
>         - city has changed owner in the 
>                                                                               
>           deep guts of CMA
>                                                                               
>         - KABOOM

And the alternative fix which uses extra checks.

        Raimar

-- 
 email: rf13@xxxxxxxxxxxxxxxxx
 "Transported to a surreal landscape, a young girl kills the first woman
  she meets and then teams up with three complete strangers to kill again."
    -- TV listing for the Wizard of Oz in the Marin Independent Journal

1888_fix1.diff
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