Re: [libvirt] [PATCH] leaseshelper: add enhancements to support all events

This patch enables the helper program to detect event(s) triggered when there is a change in lease length or expiry and client-id. This transfers complete control of leases database to libvirt and suppresses use of the lease database file (<network-name>.leases). That file will not be created, read, or written. This is achieved by adding the option --leasefile-ro to dnsmasq and applying the symlink technique, which helps us map events related to leases with their corresponding network bridges. Example: /var/lib/libvirt/dnsmasq/virbr0.helper -> /home/wani/libvirt/src/libvirt_leaseshelper /var/lib/libvirt/dnsmasq/virbr3.helper -> /home/wani/libvirt/src/libvirt_leaseshelper Also, this requires the addition of a new non-lease entry in our custom lease database: "server-duid". It is required to identify a DHCPv6 server. Now that dnsmasq doesn't maintain its own leases database, it relies on our helper program to tell it about previous leases and server duid. Thus, this patch makes our leases program honor an extra action: "init", in which it sends the known info in a particular format to dnsmasq by printing it to stdout. --- src/network/bridge_driver.c | 43 +++++++++++- src/network/leaseshelper.c | 156 +++++++++++++++++++++++++++++++++++++------- 2 files changed, 175 insertions(+), 24 deletions(-)