lighningd: Remove --debug-subdaemon-io.

We can use SIGUSR1, even in non-developer builds.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lightningd/lightningd.c

@@ -78,7 +78,6 @@ static struct lightningd *new_lightningd(const tal_t *ctx)
 	ld->reconnect = true;
 	timers_init(&ld->timers, time_mono());
 	ld->topology = new_topology(ld, ld->log);
-	ld->debug_subdaemon_io = NULL;
 	ld->daemon = false;
 	ld->pidfile = NULL;
 	ld->ini_autocleaninvoice_cycle = 0;

lightningd/lightningd.h

@@ -156,9 +156,6 @@ struct lightningd {
 	/* PID file */
 	char *pidfile;
 
-	/* May be useful for non-developers debugging in the field */
-	char *debug_subdaemon_io;
-
 	/* Initial autocleaninvoice settings. */
 	u64 ini_autocleaninvoice_cycle;
 	u64 ini_autocleaninvoice_expiredby;

lightningd/options.c

@@ -368,9 +368,6 @@ static void config_register_opts(struct lightningd *ld)
 			       opt_set_bool_arg, opt_show_bool,
 			       &deprecated_apis,
 			       "Enable deprecated options, JSONRPC commands, fields, etc.");
-	opt_register_arg("--debug-subdaemon-io",
-			 opt_set_charp, NULL, &ld->debug_subdaemon_io,
-			 "Enable full peer IO logging in subdaemons ending in this string (can also send SIGUSR1 to toggle)");
 	opt_register_arg("--autocleaninvoice-cycle",
 			 opt_set_u64, opt_show_u64,
 			 &ld->ini_autocleaninvoice_cycle,

lightningd/subd.c

@@ -135,7 +135,6 @@ static void close_taken_fds(va_list *ap)
 /* We use sockets, not pipes, because fds are bidir. */
 static int subd(const char *dir, const char *name,
 		const char *debug_subdaemon,
-		const char *debug_subdaemon_io,
 		int *msgfd, int dev_disconnect_fd, va_list *ap)
 {
 	int childmsg[2], execfail[2];
@@ -160,7 +159,7 @@ static int subd(const char *dir, const char *name,
 		int fdnum = 3, i, stdin_is_now = STDIN_FILENO;
 		long max;
 		size_t num_args;
-		char *args[] = { NULL, NULL, NULL, NULL, NULL };
+		char *args[] = { NULL, NULL, NULL, NULL };
 
 		close(childmsg[0]);
 		close(execfail[0]);
@@ -207,8 +206,6 @@ static int subd(const char *dir, const char *name,
 		if (debug_subdaemon && strends(name, debug_subdaemon))
 			args[num_args++] = "--debugger";
 #endif
-		if (debug_subdaemon_io && strends(name, debug_subdaemon_io))
-			args[num_args++] = "--log-io";
 		execv(args[0], args);
 
 	child_errno_fail:
@@ -261,7 +258,7 @@ int subd_raw(struct lightningd *ld, const char *name)
 	disconnect_fd = ld->dev_disconnect_fd;
 #endif /* DEVELOPER */
 
-	pid = subd(ld->daemon_dir, name, debug_subd, ld->debug_subdaemon_io,
+	pid = subd(ld->daemon_dir, name, debug_subd,
 		   &msg_fd, disconnect_fd,
 		   NULL);
 	if (pid == (pid_t)-1) {
@@ -658,7 +655,7 @@ static struct subd *new_subd(struct lightningd *ld,
 	disconnect_fd = ld->dev_disconnect_fd;
 #endif /* DEVELOPER */
 
-	sd->pid = subd(ld->daemon_dir, name, debug_subd, ld->debug_subdaemon_io,
+	sd->pid = subd(ld->daemon_dir, name, debug_subd,
 		       &msg_fd, disconnect_fd, ap);
 	if (sd->pid == (pid_t)-1) {
 		log_unusual(ld->log, "subd %s failed: %s",

tests/test_lightningd.py

@@ -4230,8 +4230,7 @@ class LightningDTests(BaseLightningDTests):
         l2.daemon.wait_for_log('onchaind complete, forgetting peer')
 
     def test_io_logging(self):
-        l1 = self.node_factory.get_node(options={'debug-subdaemon-io': 'channeld',
-                                                 'log-level': 'io'})
+        l1 = self.node_factory.get_node(options={'log-level': 'io'})
         l2 = self.node_factory.get_node()
         l1.rpc.connect(l2.info['id'], 'localhost', l2.port)
 
@@ -4250,6 +4249,9 @@ class LightningDTests(BaseLightningDTests):
         pid2 = re.search(r'pid ([0-9]*),', pidline).group(1)
         l2.daemon.wait_for_log(' to CHANNELD_NORMAL')
 
+        # Send it sigusr1: should turn on logging.
+        subprocess.run(['kill', '-USR1', pid1])
+
         fut = self.pay(l1, l2, 200000000, async=True)
 
         # WIRE_UPDATE_ADD_HTLC = 128 = 0x0080
@@ -4268,7 +4270,7 @@ class LightningDTests(BaseLightningDTests):
         assert not l1.daemon.is_in_log(r'channeld.*:\[IN\] 0082',
                                        start=l1.daemon.logsearch_start)
 
-        # IO logs should appear in peer logs.
+        # IO logs should not appear in peer logs.
         peerlog = l2.rpc.listpeers(l1.info['id'], "io")['peers'][0]['log']
         assert not any(l['type'] == 'IO_OUT' or l['type'] == 'IO_IN'
                        for l in peerlog)