Fix #29

src/DotNetty.Buffers/PoolChunkList.cs

@@ -74,8 +74,36 @@ public PoolChunkList(PoolArena<T> arena, PoolChunkList<T> nextList, int minUsage
  // freeBytes = 16777216 == freeMaxThreshold: 16777216, usage = 0 < minUsage: 1, chunkSize: 16777216
  // At the same time we want to have zero thresholds in case of (maxUsage == 100) and (minUsage == 100).
  //
- _freeMinThreshold = (maxUsage == 100) ? 0 : (int)(uint)(chunkSize * (100.0d - maxUsage + 0.99999999d) / 100L);
- _freeMaxThreshold = (minUsage == 100) ? 0 : (int)(uint)(chunkSize * (100.0d - minUsage + 0.99999999d) / 100L);
+ _freeMinThreshold = CalculateThresholdWithOverflow(chunkSize, maxUsage);
+ _freeMaxThreshold = CalculateThresholdWithOverflow(chunkSize, minUsage);
+ }
+
+ // https://github.com/cuteant/SpanNetty/issues/29
+ private static int CalculateThresholdWithOverflow(int chunkSize, int usage)
+ {
+ int freeThreshold;
+ if (usage == 100)
+ {
+ freeThreshold = 0;
+ }
+ else
+ {
+ var tmp = chunkSize * (100.0d - usage + 0.99999999d) / 100L;
+ if (tmp <= int.MinValue)
+ {
+ freeThreshold = int.MinValue;
+ }
+ else if (tmp >= int.MaxValue)
+ {
+ freeThreshold = int.MaxValue;
+ }
+ else
+ {
+ freeThreshold = (int)tmp;
+ }
+ }
+
+ return freeThreshold;
  }
 
  /// Calculates the maximum capacity of a buffer that will ever be possible to allocate out of the {@link PoolChunk}s