dom/streams/StreamUtils.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include "mozilla/dom/StreamUtils.h"
   6 #include "mozilla/FloatingPoint.h"
   7 #include "mozilla/dom/QueuingStrategyBinding.h"
   8
   9 namespace mozilla::dom {
  10
  11 // Streams Spec: 7.4
  12 // https://streams.spec.whatwg.org/#validate-and-normalize-high-water-mark
  13 double ExtractHighWaterMark(const QueuingStrategy& aStrategy,
  14                             double aDefaultHWM, mozilla::ErrorResult& aRv) {
  15   // Step 1.
  16   if (!aStrategy.mHighWaterMark.WasPassed()) {
  17     return aDefaultHWM;
  18   }
  19
  20   // Step 2.
  21   double highWaterMark = aStrategy.mHighWaterMark.Value();
  22
  23   // Step 3.
  24   if (mozilla::IsNaN(highWaterMark) || highWaterMark < 0) {
  25     aRv.ThrowRangeError("Invalid highWaterMark");
  26     return 0.0;
  27   }
  28
  29   // Step 4.
  30   return highWaterMark;
  31 }
  32
  33 }  // namespace mozilla::dom