diff --git a/src/freq_ctr.c b/src/freq_ctr.c
index 3df930f..28f5936 100644
--- a/src/freq_ctr.c
+++ b/src/freq_ctr.c
@@ -1,7 +1,7 @@
 /*
  * Event rate calculation functions.
  *
- * Copyright 2000-2009 Willy Tarreau <w@1wt.eu>
+ * Copyright 2000-2010 Willy Tarreau <w@1wt.eu>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -110,6 +110,82 @@
 	return MAX(wait, 1);
 }
 
+/* Reads a frequency counter taking history into account for missing time in
+ * current period. The period has to be passed in number of ticks and must
+ * match the one used to feed the counter. The counter value is reported for
+ * current date (now_ms). The return value has the same precision as one input
+ * data sample, so low rates over the period will be inaccurate but still
+ * appropriate for max checking. One trick we use for low values is to specially
+ * handle the case where the rate is between 0 and 1 in order to avoid flapping
+ * while waiting for the next event.
+ *
+ * For immediate limit checking, it's recommended to use freq_ctr_period_remain()
+ * instead which does not have the flapping correction, so that even frequencies
+ * as low as one event/period are properly handled.
+ *
+ * For measures over a 1-second period, it's better to use the implicit functions
+ * above.
+ */
+unsigned int read_freq_ctr_period(struct freq_ctr_period *ctr, unsigned int period)
+{
+	unsigned int curr, past;
+	unsigned int remain;
+
+	curr = ctr->curr_ctr;
+	past = ctr->prev_ctr;
+
+	remain = ctr->curr_tick + period - now_ms;
+	if (unlikely((int)remain < 0)) {
+		/* We're past the first period, check if we can still report a
+		 * part of last period or if we're too far away.
+		 */
+		remain += period;
+		if ((int)remain < 0)
+			return 0;
+		past = curr;
+		curr = 0;
+	}
+	if (past <= 1 && !curr)
+		return past; /* very low rate, avoid flapping */
+
+	curr += div64_32((unsigned long long)past * remain, period);
+	return curr;
+}
+
+/* Returns the number of remaining events that can occur on this freq counter
+ * while respecting <freq> events per period, and taking into account that
+ * <pend> events are already known to be pending. Returns 0 if limit was reached.
+ */
+unsigned int freq_ctr_remain_period(struct freq_ctr_period *ctr, unsigned int period,
+				    unsigned int freq, unsigned int pend)
+{
+	unsigned int curr, past;
+	unsigned int remain;
+
+	curr = ctr->curr_ctr;
+	past = ctr->prev_ctr;
+
+	remain = ctr->curr_tick + period - now_ms;
+	if (likely((int)remain < 0)) {
+		/* We're past the first period, check if we can still report a
+		 * part of last period or if we're too far away.
+		 */
+		past = curr;
+		curr = 0;
+		remain += period;
+		if ((int)remain < 0)
+			past = 0;
+	}
+	if (likely(past))
+		curr += div64_32((unsigned long long)past * remain, period);
+
+	curr += pend;
+	freq -= curr;
+	if ((int)freq < 0)
+		freq = 0;
+	return freq;
+}
+
 
 /*
  * Local variables: