tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easy GLIB has recently started to officially support the gcc cleanup attribute in its public API, hence let's do the same for our APIs. With this patch we'll define an xyz_unrefp() call for each public xyz_unref() call, to make it easy to use inside a __attribute__((cleanup())) expression. Then, all code is ported over to make use of this. The new calls are also documented in the man pages, with examples how to use them (well, I only added docs where the _unref() call itself already had docs, and the examples, only cover sd_bus_unrefp() and sd_event_unrefp()). This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we tend to call our destructors these days. Note that this defines no public macro that wraps gcc's attribute and makes it easier to use. While I think it's our duty in the library to make our stuff easy to use, I figure it's not our duty to make gcc's own features easy to use on its own. Most likely, client code which wants to make use of this should define its own: #define _cleanup_(function) __attribute__((cleanup(function))) Or similar, to make the gcc feature easier to use. Making this logic public has the benefit that we can remove three header files whose only purpose was to define these functions internally. See #2008.

tree-wide: sort includes in *.h This is a continuation of the previous include sort patch, which only sorted for .c files.

lldp: rename publicly visible structure Rename struct 'tlv_packet' to 'sd_lldp_packet' and struct 'tlv_section' to 'sd_lldp_section' since the former is referenced in public header sd-lldp.h. Signed-off-by: Beniamino Galvani <bgalvani@redhat.com>

lldp: add support for organizationally specific TLVs LLDP TLVs of type 127 are used to carry organizationally specific information and include additional fields to specify the OUI and subtype. Add support for parsing such fields and functions to access the most common IEEE 802.1 specific TLVs.

lldp: add sd_lldp_tlv_packet_get_destination_type() It can be useful to know the destination address of a LLDP frame because it determines the scope of propagation of the frame and thus this information be used to know whether the neighbor is connected to the same physical link. See clause 7.1 of IEEE Std 802.1AB-2009.

lldp: export opaque TLV type and accessor functions Export struct tlv_packet as a public opaque sd_lldp_packet type and make its accessor functions public.

lldp: add reference counter to struct tlv_packet Add a reference counter to the tlv_packet structure so that it can be shared between multiple users and properly free'd when no longer in use.

networkd: Introduce Link Layer Discovery Protocol (LLDP) This patch introduces LLDP support to networkd. it implements the receiver side of the protocol. The Link Layer Discovery Protocol (LLDP) is an industry-standard, vendor-neutral method to allow networked devices to advertise capabilities, identity, and other information onto a LAN. The Layer 2 protocol, detailed in IEEE 802.1AB-2005.LLDP allows network devices that operate at the lower layers of a protocol stack (such as Layer 2 bridges and switches) to learn some of the capabilities and characteristics of LAN devices available to higher layer protocols.