cashless2ecash

commit a6742512f6c0e20de02e7c19f94f7dde56b38d58
parent 1360db78585be5e1785ee7968d8757f4ef5f4dae
Author: Joel-Haeberli <haebu@rubigen.ch>
Date:   Wed, 22 May 2024 00:08:00 +0200

fix: last retry will be set infinitely often

Diffstat:
M
c2ec/exponential-backoff.go
 | 
24
++++++++++++++++++------

1 file changed, 18 insertions(+), 6 deletions(-)
diff --git a/c2ec/exponential-backoff.go b/c2ec/exponential-backoff.go
@@ -1,9 +1,10 @@
 package main
 
 import (
+	"crypto/rand"
 	"fmt"
 	"math"
-	"math/rand"
+	"math/big"
 	"time"
 )
 
@@ -50,15 +51,26 @@ func randomizeBackoff(backoff int64) int64 {
 
 	// it's about randomizing on millisecond base... we mustn't care about rounding
 	threshold := int64(math.Floor(float64(backoff)*RANDOMIZATION_THRESHOLD_FACTOR)) + 1 // +1 to guarantee positive threshold
-	randomizedThreshold := rand.Int63n(threshold)
-	subtract := rand.Int31n(100) // upper boundary is exclusive (value is between 0 and 99)
+	randomizedThreshold, err := rand.Int(rand.Reader, big.NewInt(backoff+threshold))
+	if err != nil {
+		LogError("exponential-backoff", err)
+	}
+	subtract, err := rand.Int(rand.Reader, big.NewInt(100)) // upper boundary is exclusive (value is between 0 and 99)
+	if err != nil {
+		LogError("exponential-backoff", err)
+	}
+
+	if !randomizedThreshold.IsInt64() {
+		LogWarn("exponential-backoff", "the threshold is not int64")
+		return backoff
+	}
 
-	if subtract < 50 {
-		subtracted := backoff - randomizedThreshold
+	if subtract.Int64() < 50 {
+		subtracted := backoff - randomizedThreshold.Int64()
 		if subtracted < 0 {
 			return 0
 		}
 		return subtracted
 	}
-	return backoff + randomizedThreshold
+	return backoff + randomizedThreshold.Int64()
 }