From d8cf3cad5104ab7a9887397b2a34d94c8a5f2aef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
Date: Fri, 2 Jun 2023 00:26:41 +0200
Subject: [PATCH] IO: Add current_time_now() function for immediate timestamp

Add a current_time_now() function which gets an immediate monotonic
timestamp instead of using the cached value from the event loop. This is
useful for callers that need precise times, such as the Babel RTT
measurement code.

Minor changes by committer.
---
 lib/timer.h      |  3 +++
 sysdep/unix/io.c | 13 +++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/lib/timer.h b/lib/timer.h
index c5ea430c..0f87852b 100644
--- a/lib/timer.h
+++ b/lib/timer.h
@@ -46,6 +46,9 @@ extern struct timeloop main_timeloop;
 btime current_time(void);
 btime current_real_time(void);
 
+/* In sysdep code */
+btime current_time_now(void);
+
 //#define now (current_time() TO_S)
 //#define now_real (current_real_time() TO_S)
 extern btime boot_time;
diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index e131ca41..6aedcfb6 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -171,6 +171,19 @@ times_update_real_time(struct timeloop *loop)
   loop->real_time = ts.tv_sec S + ts.tv_nsec NS;
 }
 
+btime
+current_time_now(void)
+{
+  struct timespec ts;
+  int rv;
+
+  rv = clock_gettime(CLOCK_MONOTONIC, &ts);
+  if (rv < 0)
+    die("clock_gettime: %m");
+
+  return ts.tv_sec S + ts.tv_nsec NS;
+}
+
 
 /**
  * DOC: Sockets