[CF-Devel] Suspicious code in server/skills.c

[crossfire-devel at archives.real-time.com]

Andreas Kirschbaum wrote:
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      In server/skills.c is a suspicious calculation:
     
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          throw_ob->stats.wc = 25-dex_bonus[op->stats.Dex?dex_bonus[op->stats.Dex]:0]-thaco_bonus[eff_str]-skill->level;
     
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      Essentially it calculates:
     
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          dex_bonus[dex_bonus[Dex]]
     
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      This can't be correct because
     
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       1. dex_bonus[] contains some negative values so it may access
     
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          dex_bonus[-1]
     
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       2. dex_bonus[1] == -3 so "Dex ? dex_bonus[Dex] : 0" is not a
     
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          sensible (monotonic increasing) function
     
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       3. dex_bonus maps "Dex" into "Wc" so "dex_bonus[Wc]" is incorrect
     
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      A possible solution could be
     
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          throw_ob->stats.wc = 25-dex_bonus[op->stats.Dex]-thaco_bonus[eff_str]-skill->level;
     
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      Is this the intended behavior?
     
     
  I've made the change you suggested - I think that is the proper behaviour - 
I'm not sure what the intention of the original code was.  Often times, there 
will be syntax like op->stats.dex?op->stats.dex:1, but the above mentioned code 
wasn't doing that.  And the 0 values for are the stat bonus arrays is properly 
intialized, so no harm using a 0 stat of dex.


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