From 2e02dce0c3de4a231f74b44c34647406de507768 Mon Sep 17 00:00:00 2001
From: rofl0r <rofl0r@users.noreply.github.com>
Date: Wed, 15 Jan 2020 17:02:22 +0000
Subject: [PATCH] conf: use 2 swappable conf slots, so old config can stay
 valid

... in case reloading of it after SIGHUP fails, the old config can
continue working.

(apart from the logging-related issue mentioned in 27d96df99900c5a62ab0fdf2a37565e78f256d6a )
---
 src/main.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/main.c b/src/main.c
index 8a3b6fa..2963957 100644
--- a/src/main.c
+++ b/src/main.c
@@ -48,11 +48,17 @@
  * Global Structures
  */
 struct config_s *config;
-static struct config_s config_main;
-static struct config_s config_defaults;
+static struct config_s configs[2];
 static const char* config_file;
 unsigned int received_sighup = FALSE;   /* boolean */
 
+static struct config_s*
+get_next_config(void)
+{
+        if (config == &configs[0]) return &configs[1];
+        return &configs[0];
+}
+
 /*
  * Handle a signal
  */
@@ -247,16 +253,17 @@ change_user (const char *program)
 int reload_config (int reload_logging)
 {
         int ret;
+        struct config_s *c_next = get_next_config();
 
         if (reload_logging) shutdown_logging ();
 
-        ret = reload_config_file (config_file, &config_main);
+        ret = reload_config_file (config_file, c_next);
 
         if (ret != 0) {
                 goto done;
         }
 
-        config = &config_main;
+        config = c_next;
 
         if (reload_logging) ret = setup_logging ();