After adding pid to the socket path the `--get-socketpath` command broke
because it doesn't know the pid of the running instance. Fix this by
setting and querying `SWAYSOCK`.
Also ignore `SWAYSOCK` upon normal startup if a socket exists at that
location (ie. from another sway instance), and don't overwrite `I3SOCK`
if it exists either.
Socket now includes pid in the filename (fixes nested sway sessions or
old sockets causing problems).
Fixed warnings on strict aliasing and cleaned up relevant code in
general.
In i3 the ipc reply will contain a human readable error message, and
this patch replicates that behaviour.
However, that error message is also useful for logging, which this
patch takes advantage of.
E.g. instead of logging errors directly in commands.c/checkargs, it is
fed back to the caller which eventually ends up logging everything with
maximum context available (config.c/read_config).
So instead of logging e.g. "Error on line 'exit'" it will now log:
"Error on line 'exit': Can't execute from config."
S. Christoffer Eliesen
Drew DeVault
Drew DeVault
minus
taiyu
Luminarys