From 34b6731b82d9f050d1347a68be418d70c491e305 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Sat, 5 Aug 2023 17:15:40 +0930
Subject: [PATCH] lightningd: don't return to a default filter level if there
 are no per-file filters.

In this case, the user's default was info, but they specifically asked for debug
from one plugin.  Since there were no per-file filters, it set filtering to the
default level, info, and rejected it.  Since it's been explicitly filtered in,
we need to pass it at this point.

Reported-by: @wtogami
Fixes: #6503
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 lightningd/log.c   | 15 ++++++++++++---
 tests/test_misc.py |  1 -
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/lightningd/log.c b/lightningd/log.c
index 59bcb2aad..4c9b6b9be 100644
--- a/lightningd/log.c
+++ b/lightningd/log.c
@@ -206,6 +206,7 @@ static void log_to_files(const char *log_prefix,
 {
 	char tstamp[sizeof("YYYY-mm-ddTHH:MM:SS.nnnZ ")];
 	char *entry, *nodestr;
+	bool filtered;
 
 	if (print_timestamps) {
 		char iso8601_msec_fmt[sizeof("YYYY-mm-ddTHH:MM:SS.%03dZ ")];
@@ -243,12 +244,15 @@ static void log_to_files(const char *log_prefix,
 
 	/* In complex configurations, we tell loggers to overshare: then we
 	 * need to filter here to see if we really want it. */
+	filtered = false;
 	if (print_filters) {
 		enum log_level filter;
 		if (filter_level(print_filters,
 				 entry_prefix, nodestr, &filter)) {
 			if (level < filter)
 				return;
+			/* Even if they specify a default filter level of 'INFO', this overrides */
+			filtered = true;
 		}
 	}
 
@@ -264,10 +268,15 @@ static void log_to_files(const char *log_prefix,
 		if (!filter_level(&log_files[i]->print_filters,
 				  entry_prefix, nodestr, &filter)) {
 			/* If we haven't set default yet, only log UNUSUAL */
-			if (default_print_level)
-				filter = *default_print_level;
-			else
+			if (!default_print_level)
 				filter = LOG_UNUSUAL;
+			else {
+				/* If we've filtered it already, it passes */
+				if (filtered)
+					filter = level;
+				else
+					filter = *default_print_level;
+			}
 		}
 		if (level < filter)
 			continue;
diff --git a/tests/test_misc.py b/tests/test_misc.py
index a62833e71..ef410852a 100644
--- a/tests/test_misc.py
+++ b/tests/test_misc.py
@@ -3076,7 +3076,6 @@ def test_log_filter(node_factory):
     assert all([' {}-'.format(l1.info['id']) in l for l in lines])
 
 
-@pytest.mark.xfail(strict=True)
 def test_log_filter_bug(node_factory):
     """Test the log-level option with overriding to a more verbose setting"""
     log_plugin = os.path.join(os.getcwd(), 'tests/plugins/log.py')