Prior to this patch, if I ran something like this, sway would crash:
swaymsg bar height 50
or
swaymsg bar not-a-bar-id color bg #ff0000
This was in contrast to other bar subcommands, like status_command,
which would exit with a "No bar defined" message.
The difference between the subcommands that crashed and the ones that
exited was that some subcommands had a check to see if a bar was
specified, while others just assumed that it had been and carried on
until they segfaulted.
Because this check was identical in every subcommand it was present in,
and I couldn't think of a case where it would be valid to run a bar
subcommand without specifying which bar to apply it to, I moved this
check from individual subcommands into the bar command, which is already
responsible for actually setting the specified bar. This reduced code
duplication, and fixed the crash for the subcommands that were missing
this check.
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.
Patch tested by compiling with `__attribute__ ((format (printf, 2, 3)))`
applied to `cmd_results_new`.
String usage constants have been converted from pointers to arrays when
encountered. General handler format strings were sometimes modified to
include the old input string, especially for unknown command errors.
