From d89a91f1f21d0953b8c6df45e747b6c33743d41a Mon Sep 17 00:00:00 2001
From: Mike Kazantsev <mk.fraggod@gmail.com>
Date: Fri, 9 Feb 2024 17:44:46 +0500
Subject: [PATCH] fix: print more descriptive error for strftime() failure on
 timestamp-prefix (#41)

Sorry for not thinking of it in #40, but this should fix non-descriptive something-about-assert-NULL error for bad timestamp-prefix format to something like this:
```
(log_proxy:269749): log_proxy-CRITICAL **: 17:37:58.678: strftime failed for timestamp-prefix: %
```
A relatively minor fix, I think.
---
 src/out.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/out.c b/src/out.c
index 1ecc76d..110f97c 100644
--- a/src/out.c
+++ b/src/out.c
@@ -96,9 +96,13 @@ gboolean write_output_channel(GString *buffer) {
     if ( _timestamp_prefix != NULL ) {
         GDateTime *dt = g_date_time_new_now_local();
         gchar *prefix = g_date_time_format(dt, _timestamp_prefix);
-        g_string_prepend(buffer, prefix);
-        g_free(prefix);
         g_date_time_unref(dt);
+        if ( prefix != NULL ) {
+            g_string_prepend(buffer, prefix);
+            g_free(prefix);
+        } else {
+            g_critical("strftime failed for timestamp-prefix: %s", _timestamp_prefix);
+        }
     }
 
     while (TRUE) {