[Fontconfig] Cache timestamping vs NFS

[Keith Packard]

Fontconfig makes sure cache files are 'up to date' by comparing the
timestamp of the cache file with the timestamp of the related directory,
if the cache is no older than the directory, then things are 'fine'.

This works correctly when the directory and cache timestamps are under
the control of the same machine. Leave the directory timestamp to
another machine and things get broken if the two machines are not
tightly synchronized in time. All too often, NFS has this problem.

As a fix, I propose writing the directory time into the cache file and
just comparing for equality. That seems far more reliable to me.

This will invalidate all existing cache files though, as the cache file
format will change.

Anyone have concerns about this plan?

-- 
keith.packard at intel.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part
Url : http://lists.freedesktop.org/archives/fontconfig/attachments/20070724/f53282b2/attachment.pgp