1 files changed, 33 insertions, 0 deletions
diff --git a/unix/utils/getticks.c b/unix/utils/getticks.c
new file mode 100644
index 00000000..9d169816
--- /dev/null
+++ b/unix/utils/getticks.c
@@ -0,0 +1,33 @@
+/*
+ * Implement getticks() for Unix.
+ */
+
+#include <time.h>
+#include <sys/time.h>
+
+#include "putty.h"
+
+unsigned long getticks(void)
+{
+    /*
+     * We want to use milliseconds rather than the microseconds or
+     * nanoseconds given by the underlying clock functions, because we
+     * need a decent number of them to fit into a 32-bit word so it
+     * can be used for keepalives.
+     */
+#if HAVE_CLOCK_GETTIME && HAVE_CLOCK_MONOTONIC
+    {
+        /* Use CLOCK_MONOTONIC if available, so as to be unconfused if
+         * the system clock changes. */
+        struct timespec ts;
+        if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
+            return ts.tv_sec * TICKSPERSEC +
+                ts.tv_nsec / (1000000000 / TICKSPERSEC);
+    }
+#endif
+    {
+        struct timeval tv;
+        gettimeofday(&tv, NULL);
+        return tv.tv_sec * TICKSPERSEC + tv.tv_usec / (1000000 / TICKSPERSEC);
+    }
+}