ratelimit start requests

1 files changed, 43 insertions, 0 deletions

diff --git a/ratelimit.c b/ratelimit.c
new file mode 100644
index 0000000000..d9eb493496
--- /dev/null
+++ b/ratelimit.c
@@ -0,0 +1,43 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+#include <assert.h>
+
+#include "ratelimit.h"
+#include "log.h"
+
+/* Modelled after Linux' lib/ratelimit.c by Dave Young
+ * <hidave.darkstar@gmail.com>, which is licensed GPLv2. */
+
+bool ratelimit_test(RateLimit *r) {
+        usec_t timestamp;
+
+        timestamp = now(CLOCK_MONOTONIC);
+
+        assert(r);
+        assert(r->interval > 0);
+        assert(r->burst > 0);
+
+        if (r->begin <= 0 ||
+            r->begin + r->interval < timestamp) {
+
+                if (r->n_missed > 0)
+                        log_warning("%u events suppressed", r->n_missed);
+
+                r->begin = timestamp;
+
+                /* Reset counters */
+                r->n_printed = 0;
+                r->n_missed = 0;
+                goto good;
+        }
+
+        if (r->n_printed <= r->burst)
+                goto good;
+
+        r->n_missed++;
+        return false;
+
+good:
+        r->n_printed++;
+        return true;
+}