GCC 10 defaults to `-fno-common`. no longer automatically sharing
global variable definitions, which makes it important to define
them in only one place (otherwise there will be duplicate definition
errors). Add `extern` qualifiers where (I think) is the best place for
them.
This currently just invokes GDB, but we could generalize it (though
pdb doesn't allow attaching to a running process, other python
debuggers seem to).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Code changes:
1. Expose daemon_poll() so lightningd can call it directly, which avoids us
having store a global and document it.
2. Remove the (undocumented, unused, forgotten) --rpc-file="" option to disable
JSON RPC.
3. Move the ickiness of finding the executable path into subd.c, so it doesn't
distract from lightningd.c overview.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In particular, the main daemon and subdaemons share the backtrace code,
with hooks for logging.
The daemon hook inserts the io_poll override, which means we no longer
need io_debug.[ch]. Though most daemons don't need it, they still link
against ccan/io, so it's harmess (suggested by @ZmnSCPxj).
This was tested manually to make sure we get backtraces still.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
