glib: add compatibility interface for g_get_monotonic_time()

This patch fixes compilation errors when building against glib <2.28.0
due to the missing g_get_monotonic_time() function.

The compilation error in tests/libqos/virtio.c was introduced in commit
70556264a89a268efba1d7e8e341adcdd7881eb4 ("libqos: use microseconds
instead of iterations for virtio timeout").

Add a simple g_get_monotonic_time() implementation to glib-compat.h
based on code from vhost-user-test.c.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
[Igor: add G_TIME_SPAN_SECOND, include glib-compat.h in libqtest.h]
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/include/glib-compat.h b/include/glib-compat.h
index 4ae0671..e29bf69 100644
--- a/include/glib-compat.h
+++ b/include/glib-compat.h
@@ -18,6 +18,11 @@
 
 #include <glib.h>
 
+/* GLIB version compatibility flags */
+#if !GLIB_CHECK_VERSION(2, 26, 0)
+#define G_TIME_SPAN_SECOND              (G_GINT64_CONSTANT(1000000))
+#endif
+
 #if !GLIB_CHECK_VERSION(2, 14, 0)
 static inline guint g_timeout_add_seconds(guint interval, GSourceFunc function,
                                           gpointer data)
@@ -26,6 +31,20 @@ static inline guint g_timeout_add_seconds(guint interval, GSourceFunc function,
 }
 #endif
 
+#if !GLIB_CHECK_VERSION(2, 28, 0)
+static inline gint64 g_get_monotonic_time(void)
+{
+    /* g_get_monotonic_time() is best-effort so we can use the wall clock as a
+     * fallback.
+     */
+
+    GTimeVal time;
+    g_get_current_time(&time);
+
+    return time.tv_sec * G_TIME_SPAN_SECOND + time.tv_usec;
+}
+#endif
+
 #ifdef _WIN32
 /*
  * g_poll has a problem on Windows when using