[mkgmap-dev] Error in gmapsupp blocksize calculation with huge number of tiles

Thu Apr 4 10:10:33 BST 2024

Hi all

see https://www.mkgmap.org.uk/pipermail/mkgmap-dev/2024q2/034252.html
I think the experiments by Felix Herwegh showed a bug in the blocksize calculation. If the user combines a huge number of tiles (e.g. 6000) in one gmapsupp
the code may not find the best blocksize due to an integer overflow. Not sure, maybe this also happens with < 2048 tiles in some cases. 

The attached patch fixes the calculation. It will result in smaller gmapsupp sizes where the error occured.

Gerd

-------------- next part --------------
A non-text attachment was scrubbed...
Name: blksize.patch
Type: application/octet-stream
Size: 1006 bytes
Desc: blksize.patch
URL: <https://www.mkgmap.org.uk/pipermail/mkgmap-dev/attachments/20240404/e871fadc/attachment.obj>