Avoid assert crash after bytestream position wrap around
Fixes #652.
diff --git a/common/rfb/Congestion.cxx b/common/rfb/Congestion.cxx
index 4d36d9f..8162808 100644
--- a/common/rfb/Congestion.cxx
+++ b/common/rfb/Congestion.cxx
@@ -68,6 +68,11 @@
// limit for now...
static const unsigned MAXIMUM_WINDOW = 4194304;
+// Compare position even when wrapped around
+static inline bool isAfter(unsigned a, unsigned b) {
+ return (int)a - (int)b > 0;
+}
+
static LogWriter vlog("Congestion");
Congestion::Congestion() :
@@ -230,7 +235,7 @@
targetAcked = lastPosition - congWindow;
// Simple case?
- if (lastPong.pos > targetAcked)
+ if (isAfter(lastPong.pos, targetAcked))
return 0;
// No measurements yet?
@@ -269,7 +274,7 @@
etaNext -= delay;
// Found it?
- if (curPing.pos > targetAcked) {
+ if (isAfter(curPing.pos, targetAcked)) {
eta += etaNext * (curPing.pos - targetAcked) / (curPing.pos - prevPing->pos);
if (elapsed > eta)
return 0;