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.

dhcp: make DHCP_OPTION_* enum public libsystemd-network provides the public function sd_dhcp_client_set_request_option() to enable the request of a given DHCP option. However the enum defining such options is defined in the internal header dhcp-protocol.h. Move the enum definition to the public header sd-dhcp-client.h and properly namespace values.

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.

siphash24: let siphash24_finalize() and siphash24() return the result directly Rather than passing a pointer to return the result, return it directly from the function calls. Also, return the result in native endianess, and let the callers care about the conversion. For hash tables and bloom filters, we don't care, but in order to keep MAC addresses and DHCP client IDs stable, we explicitly convert to LE.

siphash24: change result argument to uint64_t Change the "out" parameter from uint8_t[8] to uint64_t. On architectures which enforce pointer alignment this fixes crashes when we previously cast an unaligned array to uint64_t*, and on others this should at least improve performance as the compiler now aligns these properly. This also simplifies the code in most cases by getting rid of typecasts. The only place which we can't change is struct duid's en.id, as that is _packed_ and public API, so we can't enforce alignment of the "id" field and have to use memcpy instead.

util-lib: split our string related calls from util.[ch] into its own file string-util.[ch] There are more than enough calls doing string manipulations to deserve its own files, hence do something about it. This patch also sorts the #include blocks of all files that needed to be updated, according to the sorting suggestions from CODING_STYLE. Since pretty much every file needs our string manipulation functions this effectively means that most files have sorted #include blocks now. Also touches a few unrelated include files.

siphash24: unify API Make the API of the new helpers more similar to the old wrapper. In particular we now return the hash as a byte string to avoid any endianness problems.

hashmap: refactor hash_func All our hash functions are based on siphash24(), factor out siphash_init() and siphash24_finalize() and pass the siphash state to the hash functions rather than the hash key. This simplifies the hash functions, and in particular makes composition simpler as calling siphash24_compress() repeatedly on separate chunks of input has the same effect as first concatenating the input and then calling siphash23_compress() on the result.

sd-dhcp-server: simplify pool creation Merge sd_dhcp_server_set_address() and sd_dhcp_server_set_lease_pool() into sd_dhcp_server_configure_pool() as the behavior of the two former depends on the order they are called in. The flexibility is not needed, so let's just do this in one call.

remove unused includes This patch removes includes that are not used. The removals were found with include-what-you-use which checks if any of the symbols from a header is in use.

test: dhcp-server - fix test Reported by Corey Hammerton on G+

sd-dhcp-server: always send out ROUTER and SUBNET_MASK For now we simply take these values from the server's address.

sd-dhcp-server: test - skip when lacking perms

sd-dhcp-server: track bound leases Make sure we don't hand out the same IP twice. We still don't handle lease expiry.

sd-dhcp-server: add basic NAK support

sd-dhcp-server: add basic REQUEST/ACK support

sd-dhcp-server: add basic DISCOVER/OFFER support

sd-dhcp-server: add support for setting the server address

sd-dhcp-server: add basic message handling and verification

sd-dhcp-server: bind to a given interface We will (at least at first), restrict our focus to running the server on at most one interface.

sd-dhcp-server: add basic functionality for starting/stopping server Bind to UDP socket and listen for messages, discarding anything we receive.

sd-dhcp-server: add basic functionality for creating/destroying server instance