[PATCH 7/7] virtiofsd: use GDateTime for formatting timestamp for debug messages

["Daniel P. Berrangé" <berrange@redhat.com>]

The GDateTime APIs provided by GLib avoid portability pitfalls, such
as some platforms where 'struct timeval.tv_sec' field is still 'long'
instead of 'time_t'. When combined with automatic cleanup, GDateTime
often results in simpler code too.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 tools/virtiofsd/passthrough_ll.c | 25 ++++---------------------
 1 file changed, 4 insertions(+), 21 deletions(-)

diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index 1553d2ef45..cdd224918c 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -3558,10 +3558,6 @@ static void setup_nofile_rlimit(unsigned long rlimit_nofile)
 static void log_func(enum fuse_log_level level, const char *fmt, va_list ap)
 {
     g_autofree char *localfmt = NULL;
-    struct timespec ts;
-    struct tm tm;
-    char sec_fmt[sizeof "2020-12-07 18:17:54"];
-    char zone_fmt[sizeof "+0100"];
 
     if (current_log_level < level) {
         return;
@@ -3573,23 +3569,10 @@ static void log_func(enum fuse_log_level level, const char *fmt, va_list ap)
             localfmt = g_strdup_printf("[ID: %08ld] %s", syscall(__NR_gettid),
                                        fmt);
         } else {
-            /* try formatting a broken-down timestamp */
-            if (clock_gettime(CLOCK_REALTIME, &ts) != -1 &&
-                localtime_r(&ts.tv_sec, &tm) != NULL &&
-                strftime(sec_fmt, sizeof sec_fmt, "%Y-%m-%d %H:%M:%S",
-                         &tm) != 0 &&
-                strftime(zone_fmt, sizeof zone_fmt, "%z", &tm) != 0) {
-                localfmt = g_strdup_printf("[%s.%02ld%s] [ID: %08ld] %s",
-                                           sec_fmt,
-                                           ts.tv_nsec / (10L * 1000 * 1000),
-                                           zone_fmt, syscall(__NR_gettid),
-                                           fmt);
-            } else {
-                /* fall back to a flat timestamp */
-                localfmt = g_strdup_printf("[%" PRId64 "] [ID: %08ld] %s",
-                                           get_clock(), syscall(__NR_gettid),
-                                           fmt);
-            }
+            g_autoptr(GDateTime) now = g_date_time_new_now_local();
+            g_autofree char *nowstr = g_date_time_format(now, "%Y-%m-%d %H:%M:%S.%f%z");
+            localfmt = g_strdup_printf("[%s] [ID: %08ld] %s",
+                                       nowstr, syscall(__NR_gettid), fmt);
         }
         fmt = localfmt;
     }
-- 
2.31.1