conf-parser: ignore trailing back-slash in comment

Fixes #10598.

src/test/test-conf-parser.c

@@ -274,6 +274,18 @@ static const char* const config_file[] = {
         "2\\\n"
         "3\n",
 
+        "[Section]\n"
+        "#hogehoge\\\n"      /* continuation is ignored in comment */
+        "setting1=1\\\n"     /* normal continuation */
+        "2\\\n"
+        "3\n",
+
+        "[Section]\n"
+        "setting1=1\\\n"     /* normal continuation */
+        "#hogehoge\\\n"      /* commented out line in continuation is ignored */
+        "2\\\n"
+        "3\n",
+
         "[Section]\n"
         "setting1=1\\\n"     /* continuation with extra trailing backslash at the end */
         "2\\\n"
@@ -350,27 +362,27 @@ static void test_config_parse(unsigned i, const char *s) {
                 assert_se(streq(setting1, "1"));
                 break;
 
-        case 4 ... 5:
+        case 4 ... 7:
                 assert_se(r == 0);
                 assert_se(streq(setting1, "1 2 3"));
                 break;
 
-        case 6:
+        case 8:
                 assert_se(r == 0);
                 assert_se(streq(setting1, "1\\\\ \\\\2"));
                 break;
 
-        case 7:
+        case 9:
                 assert_se(r == 0);
                 assert_se(streq(setting1, x1000("ABCD")));
                 break;
 
-        case 8 ... 9:
+        case 10 ... 11:
                 assert_se(r == 0);
                 assert_se(streq(setting1, x1000("ABCD") " foobar"));
                 break;
 
-        case 10 ... 11:
+        case 12 ... 13:
                 assert_se(r == -ENOBUFS);
                 assert_se(setting1 == NULL);
                 break;