Unfortunately, sptps_logger() cannot know if s->handle is pointing to a
connection_t or a node_t. But it needs to print name and hostname in
both cases. So make sure both types have name and hostname fields at the
start with the same offset.
We do this by creating an umbilical between the CLI and the daemon. The
daemon pipes log messages to the CLI until it starts the main loop. The
daemon then cuts the umbilical. The CLI copies all the received log
messages to stderr, and the last byte indicates whether the daemon
started succesfully or not, so the CLI can exit with a useful exit code.
There are several reasons for this:
- MacOS/X doesn't support polling the tap device using kqueue, requiring a
workaround to fall back to select().
- On Windows only sockets are properly handled, therefore tinc uses a second
thread that does a blocking ReadFile() on the TAP-Win32/64 device. However,
this does not mix well with libevent.
- Libevent, event just the core, is quite large, and although it is easy to get
and install on many platforms, it can be a burden.
- Libev is more lightweight and seems technically superior, but it doesn't
abstract away all the platform differences (for example, async events are not
supported on Windows).
The tree functions were never used on the connection_tree, a list is more appropriate.
Also be more paranoid about connections disappearing while traversing the list.
This allows tincctl to receive log messages from a running tincd,
independent of what is logged to syslog or to file. Tincctl can receive
debug messages with an arbitrary level.
Instead of UNIX time, the log messages now start with the time in RFC3339
format, which human-readable and still easy for the computer to parse and sort.
The HUP signal will also cause the log file to be closed and reopened, which is
useful when log rotation is used. If there is an error while opening the log
file, this is logged to stderr.
