third_party/woff2/src/round.h

   1 // Copyright 2013 Google Inc. All Rights Reserved.
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 // http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14 //
  15 // Helper for rounding
  16
  17 #ifndef WOFF2_ROUND_H_
  18 #define WOFF2_ROUND_H_
  19
  20 #include <limits>
  21
  22 namespace woff2 {
  23
  24 // Round a value up to the nearest multiple of 4. Don't round the value in the
  25 // case that rounding up overflows.
  26 template<typename T> T Round4(T value) {
  27   if (std::numeric_limits<T>::max() - value < 3) {
  28     return value;
  29   }
  30   return (value + 3) & ~3;
  31 }
  32
  33 } // namespace woff2
  34
  35 #endif  // WOFF2_ROUND_H_