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.

resolved,networkd: unify ResolveSupport enum networkd previously knew an enum "ResolveSupport" for configuring per-interface LLMNR support, resolved had a similar enum just called "Support", with the same value and similar pasers. Unify this, call the enum ResolveSupport, and port both daemons to it.

basic: add string table macros for "extended boolean" enums In a couple of cases we maintain configuration settings that know an on and off state, like a boolean, plus some additional states. We generally parse them as booleans first, and if that fails check for specific additional values. This adds a generalized set of macros for parsing such settings, and ports one use in resolved and another in networkd over to it.

networkd: stop managing per-interface IP forwarding settings As it turns out the kernel does not support per-interface IPv6 packet forwarding controls (unlike as it does for IPv4), but only supports a global option (#1597). Also, the current per-interface management of the setting isn't really useful, as you want it to propagate to at least one more interface than the one you configure it on. This created much grief (#1411, #1808). Hence, let's roll this logic back and simplify this again, so that we can expose the same behaviour on IPv4 and IPv6 and things start to work automatically again for most folks: if a network with this setting set is set up we propagate the setting into the global setting, but this is strictly one-way: we never reset it again, and we do nothing for network interfaces where this setting is not enabled. Fixes: #1808, #1597.

networkd: fix option name in log message

util-lib: move string table stuff into its own string-table.[ch]

util-lib: split string parsing related calls from util.[ch] into parse-util.[ch]

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.

tree-wide: clean up log_syntax() usage - Rely everywhere that we use abs() on the error code passed in anyway, thus don't need to explicitly negate what we pass in - Never attach synthetic error number information to log messages. Only log about errors we *receive* with the error number we got there, don't log any synthetic error, that don#t even propagate, but just eat up. - Be more careful with attaching exactly the error we get, instead of errno or unrelated errors randomly. - Fix one occasion where the error number and line number got swapped. - Make sure we never tape over OOM issues, or inability to resolve specifiers

networkd: split up networkd.h into per-object header files No functional changes, just moving definitions into separate header files.