[gdal-dev] Call for discusson on RFC 31 - OGR 64bit Integer Fields and FIDs

[Daniel Morissette]

Merci!

Daniel

On 2015-01-28 7:01 AM, Even Rouault wrote:
> Daniel,
>
>>
>> This may not be true on all platforms, but at least with GCC, we get
>> warnings in a case like this, e.g.
>>
>>
>> #include <stdio.h>
>> #include <stdint.h>
>>
>> int main()
>> {
>>     int64_t id=10;
>>
>>     printf ("%d %s\n", id, "test");
>>     return 0;
>> }
>>
>>
>> $ gcc -Wall ttt.c -o ttt
>> ttt.c: In function 'main':
>> ttt.c:8: warning: format '%ld' expects type 'long int', but argument 2
>> has type 'int64_t'
>>
>>> I've taken that approach from Frank's initial draft and that seamed a
>>> valid concern. That said, if you guys think that changing the return
>>> type is better, I've no strong mind.
>>
>> I don't feel that strongly about it. I was mostly wondering if there
>> would be a way to avoid the *64() suffixes.
>
> Yes GCC nicely warns. I don't think MSVC does, but oh well people building on
> Windows are used to self-inflicted pain ;-)
>
> So I've renamed GetFID64() -> GetFID() and GetFeatureCount64() -> GetFeature()
> in latest commit :
> https://github.com/rouault/gdal2/commit/40eb13bb9e2a4c86df9d3cf4d030ab14d67749d5
>
>>
>>>> Also note that in the list of driver upgrades, you could add potential
>>>> enhancement to the support for MITAB "TAB Seamless Tables" which had a
>>>> potential FID overflow problem on very large tables with 32 bit ids. The
>>>> driver would have caught and reported an error in this case, but that
>>>> limitation can be solved with 64 bit ids if/when the code is upgraded to
>>>> use them. Look for TABSeamless::EncodeFeatureId() and related methods in
>>>> mitab_tabseamless.cpp.
>>>
>
> I've made changes in TABSeamless and now builds a 64 bit FID  with the upper
> 32bits being for the index table and the lower 32bits for the feature within
> the table.
> Looking at the code, I've manually forged a simple seamless table and added it
> in autotest.
> https://github.com/rouault/gdal2/commit/a922228eff8d0b07918db520de142154e8454f6a
>


-- 
Daniel Morissette
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