From c161ca023fe9be31016407172f52145cddc6f94b Mon Sep 17 00:00:00 2001
From: Lorenzo Miniero <lminiero@gmail.com>
Date: Tue, 9 Jul 2024 16:59:31 +0200
Subject: [PATCH] Normalize the return value of janus_get_monotonic_time()

---
 src/janus.c |  1 +
 src/utils.c | 12 +++++++++++-
 src/utils.h |  4 ++++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/janus.c b/src/janus.c
index f0153d27da..3151e8b1d4 100644
--- a/src/janus.c
+++ b/src/janus.c
@@ -4408,6 +4408,7 @@ gint main(int argc, char *argv[]) {
 	g_print("Janus version: %d (%s)\n", janus_version, janus_version_string);
 	g_print("Janus commit: %s\n", janus_build_git_sha);
 	g_print("Compiled on:  %s\n\n", janus_build_git_time);
+	janus_mark_started();
 
 	/* Initialize some command line options defaults */
 	options.debug_level = -1;
diff --git a/src/utils.c b/src/utils.c
index 0aa13f3823..409a0cc50b 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -31,12 +31,22 @@
 #include "mach_gettime.h"
 #endif
 
-gint64 janus_get_monotonic_time(void) {
+static gint64 janus_get_monotonic_time_internal(void) {
 	struct timespec ts;
 	clock_gettime (CLOCK_MONOTONIC, &ts);
 	return (ts.tv_sec*G_GINT64_CONSTANT(1000000)) + (ts.tv_nsec/G_GINT64_CONSTANT(1000));
 }
 
+static gint64 janus_started = 0;
+void janus_mark_started(void) {
+	if(janus_started == 0)
+		janus_started = janus_get_monotonic_time_internal();
+}
+
+gint64 janus_get_monotonic_time(void) {
+	return janus_get_monotonic_time_internal() - janus_started;
+}
+
 gint64 janus_get_real_time(void) {
 	struct timespec ts;
 	clock_gettime (CLOCK_REALTIME, &ts);
diff --git a/src/utils.h b/src/utils.h
index 4630a1b6c4..6bb68981e1 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -40,8 +40,12 @@ struct janus_json_parameter {
 #endif
 
 
+/*! Helper method used by the core to mark when Janus started */
+void janus_mark_started(void);
+
 /*! \brief Helper to retrieve the system monotonic time, as Glib's
  * g_get_monotonic_time may not be available (only since 2.28)
+ * @note The monotonic time will be normalized from the Janus start time
  * @returns The system monotonic time */
 gint64 janus_get_monotonic_time(void);