[PATCH] debuginfod: debuginfod client would cache negative results.

[Mark Wielaard]

Hi Alice,

On Tue, May 04, 2021 at 04:25:59PM -0400, Alice Zhang via Elfutils-devel wrote:
> add debuginfod_config_cache for reading and writing to cache
> configuration files, make use of the function within
> debuginfod_clean_cache and debuginfod_query_server.
> 
> in debuginfod_query_server, create 000-permission file on failed
> queries. Before querying each BUILDID, if corresponding 000 file
> detected, compare its stat mtime with parameter from
> .cache/cache_miss_s. if mtime is fresher, then return ENOENT and
> exit; otherwise unlink the 000 file and proceed to a new query.
> 
> tests: add test in run-debuginfod-find.sh
> 
> test if the 000 file is created on failed query; if querying the
> same failed BUILDID, whether the query should proceed without
> going through server; set the cache_miss_s to 0 and query the same
> buildid, and this time should go through the server.

This looks really good. I rebased it, added slightly bigger ChangeLog
entries and reindented the code in places where it was > 80 chars and
pushed the result.

Thanks,

Mark