Patches 1 & 2 were posted previously here:
https://www.redhat.com/archives/libguestfs/2016-May/msg00134.html
Patch 3 is a hack so I can test this using my own version of qemu (the
`-L ?' stuff is not upstream).
Patch 4 is where the real action takes place: Replace the caching of
qemu features in blob-like files with a sqlite database. Probably the
best way to approach this patch is to start with the schema
(src/qemu-schema.sql) and the sqlite C API documentation
(
https://www.sqlite.org/cintro.html).
Rich.