However, bundled XPC services still don't work properly.
The problem is that bundled XPC service support needs to be implemented in launchd.
The open-source launchd sources are severely outdated, much like CoreFoundation.
The new launchd is based on libxpc and is closed-source.
We probably don't want to completely rewrite launchd, but at the very least, we do need to add support for new XPC-based features.
As noted in `plist.m`, the XML parsing implemented here is NOT robust, but it's good enough for the vast majority of files.
This commit also adds many new String methods. It also fixes an issue where syslogd would get stuck trying to send a message to itself due to our logging.
Also includes a serialization overhaul to be more object-oriented (each XPC object class worries about its own (de)serialization). The new serialization code also includes Mach port serialization (which we didn't have before).
The "test" service is not really a test; it's more of a sample. You have to test it out manually.
This commit is the first in the rewrite of libxpc. It implements the basic API (that is, the XPC object system and the most basic objects and collections). It also adds some tests for the basic API.
The current test suite uses ctest as the testing framework, but for future tests (such as for connections), it may be necessary to find something a little more robust (or roll our own).
Future commits will implement the rewritten connection system based on top of libdispatch's private Mach API, which is made specifically for this purpose (it even has certain methods marked as `4libxpc`).
