diff options
Diffstat (limited to 'vendor/k8s.io/apimachinery/pkg/api/resource/scale_int.go')
-rw-r--r-- | vendor/k8s.io/apimachinery/pkg/api/resource/scale_int.go | 95 |
1 files changed, 0 insertions, 95 deletions
diff --git a/vendor/k8s.io/apimachinery/pkg/api/resource/scale_int.go b/vendor/k8s.io/apimachinery/pkg/api/resource/scale_int.go deleted file mode 100644 index 55e177b0e..000000000 --- a/vendor/k8s.io/apimachinery/pkg/api/resource/scale_int.go +++ /dev/null @@ -1,95 +0,0 @@ -/* -Copyright 2015 The Kubernetes Authors. - -Licensed under the Apache License, Version 2.0 (the "License"); -you may not use this file except in compliance with the License. -You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - -Unless required by applicable law or agreed to in writing, software -distributed under the License is distributed on an "AS IS" BASIS, -WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -See the License for the specific language governing permissions and -limitations under the License. -*/ - -package resource - -import ( - "math" - "math/big" - "sync" -) - -var ( - // A sync pool to reduce allocation. - intPool sync.Pool - maxInt64 = big.NewInt(math.MaxInt64) -) - -func init() { - intPool.New = func() interface{} { - return &big.Int{} - } -} - -// scaledValue scales given unscaled value from scale to new Scale and returns -// an int64. It ALWAYS rounds up the result when scale down. The final result might -// overflow. -// -// scale, newScale represents the scale of the unscaled decimal. -// The mathematical value of the decimal is unscaled * 10**(-scale). -func scaledValue(unscaled *big.Int, scale, newScale int) int64 { - dif := scale - newScale - if dif == 0 { - return unscaled.Int64() - } - - // Handle scale up - // This is an easy case, we do not need to care about rounding and overflow. - // If any intermediate operation causes overflow, the result will overflow. - if dif < 0 { - return unscaled.Int64() * int64(math.Pow10(-dif)) - } - - // Handle scale down - // We have to be careful about the intermediate operations. - - // fast path when unscaled < max.Int64 and exp(10,dif) < max.Int64 - const log10MaxInt64 = 19 - if unscaled.Cmp(maxInt64) < 0 && dif < log10MaxInt64 { - divide := int64(math.Pow10(dif)) - result := unscaled.Int64() / divide - mod := unscaled.Int64() % divide - if mod != 0 { - return result + 1 - } - return result - } - - // We should only convert back to int64 when getting the result. - divisor := intPool.Get().(*big.Int) - exp := intPool.Get().(*big.Int) - result := intPool.Get().(*big.Int) - defer func() { - intPool.Put(divisor) - intPool.Put(exp) - intPool.Put(result) - }() - - // divisor = 10^(dif) - // TODO: create loop up table if exp costs too much. - divisor.Exp(bigTen, exp.SetInt64(int64(dif)), nil) - // reuse exp - remainder := exp - - // result = unscaled / divisor - // remainder = unscaled % divisor - result.DivMod(unscaled, divisor, remainder) - if remainder.Sign() != 0 { - return result.Int64() + 1 - } - - return result.Int64() -} |