This commit mostly duplicates the wlr_log functions, although
with a sway_* prefix. (This is very similar to PR #2009.)
However, the logging function no longer needs to be replaceable,
so sway_log_init's second argument is used to set the exit
callback for sway_abort.
wlr_log_init is still invoked in sway/main.c
This commit makes it easier to remove the wlroots dependency for
the helper programs swaymsg, swaybg, swaybar, and swaynag.
Previously, the success of `getline` was tested by checking if the
buffer it allocates is nonempty and has a nonzero first byte. As
`getline` does not explicitly zero out its memory buffer, this may
fail (e.g., with AddressSanitizer). Instead, we check that at least one
character was returned on standard output.
Also, trailing newlines (if present) are now removed.
When sway crashes a swaybar process is sometimes left behind running at
100% CPU. This was caused by the swaybar trying to retrieve an IPC
response from the closed sway socket.
This patch fixes the problem by aborting when the socket has been closed
(recv return 0).
Fix#528
Makes `ipc_recv_response` return a struct with size, type and payload
rather than just the payload string.
This is useful if the type has to be checked on the client.
