[postgis-users] msPOSTGISLayerCLose() called twice

[Daniel Morissette]

David Blasby wrote:
> Daniel Morissette wrote:
> 
>> I don't think it's right for the pooling code to call close a second 
>> time, but it wouldn't hurt anyway to modify msPOSTGISLayerClose() to 
>> check if the layer is still open before closing it.  From MapScript 
>> it's possible for a script to call $layer->close() twice, a mistake 
>> that will be very common in scripts I'm sure, so it would be better if 
>> calling close twice didn't crash the server but instead either 
>> returned silently or produced an error.
> 
> 
> 
> msPOSTGISLayerClose() doesnt do anything if the layer is already close. 
>  I just though this was quite strange that it was getting called more 
> than it ought to have.  I looked like an indication of a larger problem.
> 
> Also, whats an itemnquery supposed to do (from the perspective of the 
> layer)?
> 
> dave
> 

I barely ever use the mapserv CGI myself so I am not sure what 
itemnquery should do so you might be better ask this on mapserver-dev.

However, looking at the source it seems that itemnquery calls 
msQueryByAttributes().  And looking at msQueryByAttributes(), the 
sequence of calls is:

   msLayerOpen()
   msLayerWhichItems()  (this one is internal, it doesn't call postgis)
   msLayerWhichShapes()
   iterate on msLayerNextShape() until all shapes have been read
   msLayerClose()


Daniel
-- 
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  Daniel Morissette               morissette at dmsolutions.ca
  DM Solutions Group              http://www.dmsolutions.ca/
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