mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-12-05 20:50:24 +00:00
f60a07ae82
some of the kubernetes independent packages are moved out of the tree to new projects. Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
739 lines
21 KiB
Go
739 lines
21 KiB
Go
/*
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Copyright 2014 The Kubernetes Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package resource
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import (
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"bytes"
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"errors"
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"fmt"
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"math/big"
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"strconv"
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"strings"
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inf "gopkg.in/inf.v0"
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)
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// Quantity is a fixed-point representation of a number.
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// It provides convenient marshaling/unmarshaling in JSON and YAML,
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// in addition to String() and Int64() accessors.
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//
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// The serialization format is:
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//
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// <quantity> ::= <signedNumber><suffix>
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// (Note that <suffix> may be empty, from the "" case in <decimalSI>.)
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// <digit> ::= 0 | 1 | ... | 9
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// <digits> ::= <digit> | <digit><digits>
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// <number> ::= <digits> | <digits>.<digits> | <digits>. | .<digits>
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// <sign> ::= "+" | "-"
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// <signedNumber> ::= <number> | <sign><number>
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// <suffix> ::= <binarySI> | <decimalExponent> | <decimalSI>
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// <binarySI> ::= Ki | Mi | Gi | Ti | Pi | Ei
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// (International System of units; See: http://physics.nist.gov/cuu/Units/binary.html)
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// <decimalSI> ::= m | "" | k | M | G | T | P | E
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// (Note that 1024 = 1Ki but 1000 = 1k; I didn't choose the capitalization.)
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// <decimalExponent> ::= "e" <signedNumber> | "E" <signedNumber>
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//
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// No matter which of the three exponent forms is used, no quantity may represent
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// a number greater than 2^63-1 in magnitude, nor may it have more than 3 decimal
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// places. Numbers larger or more precise will be capped or rounded up.
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// (E.g.: 0.1m will rounded up to 1m.)
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// This may be extended in the future if we require larger or smaller quantities.
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//
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// When a Quantity is parsed from a string, it will remember the type of suffix
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// it had, and will use the same type again when it is serialized.
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//
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// Before serializing, Quantity will be put in "canonical form".
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// This means that Exponent/suffix will be adjusted up or down (with a
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// corresponding increase or decrease in Mantissa) such that:
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// a. No precision is lost
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// b. No fractional digits will be emitted
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// c. The exponent (or suffix) is as large as possible.
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// The sign will be omitted unless the number is negative.
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//
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// Examples:
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// 1.5 will be serialized as "1500m"
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// 1.5Gi will be serialized as "1536Mi"
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//
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// Note that the quantity will NEVER be internally represented by a
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// floating point number. That is the whole point of this exercise.
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//
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// Non-canonical values will still parse as long as they are well formed,
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// but will be re-emitted in their canonical form. (So always use canonical
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// form, or don't diff.)
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//
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// This format is intended to make it difficult to use these numbers without
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// writing some sort of special handling code in the hopes that that will
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// cause implementors to also use a fixed point implementation.
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//
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// +protobuf=true
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// +protobuf.embed=string
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// +protobuf.options.marshal=false
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// +protobuf.options.(gogoproto.goproto_stringer)=false
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// +k8s:deepcopy-gen=true
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// +k8s:openapi-gen=true
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type Quantity struct {
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// i is the quantity in int64 scaled form, if d.Dec == nil
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i int64Amount
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// d is the quantity in inf.Dec form if d.Dec != nil
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d infDecAmount
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// s is the generated value of this quantity to avoid recalculation
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s string
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// Change Format at will. See the comment for Canonicalize for
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// more details.
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Format
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}
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// CanonicalValue allows a quantity amount to be converted to a string.
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type CanonicalValue interface {
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// AsCanonicalBytes returns a byte array representing the string representation
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// of the value mantissa and an int32 representing its exponent in base-10. Callers may
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// pass a byte slice to the method to avoid allocations.
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AsCanonicalBytes(out []byte) ([]byte, int32)
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// AsCanonicalBase1024Bytes returns a byte array representing the string representation
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// of the value mantissa and an int32 representing its exponent in base-1024. Callers
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// may pass a byte slice to the method to avoid allocations.
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AsCanonicalBase1024Bytes(out []byte) ([]byte, int32)
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}
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// Format lists the three possible formattings of a quantity.
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type Format string
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const (
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DecimalExponent = Format("DecimalExponent") // e.g., 12e6
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BinarySI = Format("BinarySI") // e.g., 12Mi (12 * 2^20)
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DecimalSI = Format("DecimalSI") // e.g., 12M (12 * 10^6)
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)
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// MustParse turns the given string into a quantity or panics; for tests
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// or others cases where you know the string is valid.
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func MustParse(str string) Quantity {
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q, err := ParseQuantity(str)
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if err != nil {
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panic(fmt.Errorf("cannot parse '%v': %v", str, err))
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}
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return q
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}
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const (
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// splitREString is used to separate a number from its suffix; as such,
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// this is overly permissive, but that's OK-- it will be checked later.
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splitREString = "^([+-]?[0-9.]+)([eEinumkKMGTP]*[-+]?[0-9]*)$"
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)
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var (
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// Errors that could happen while parsing a string.
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ErrFormatWrong = errors.New("quantities must match the regular expression '" + splitREString + "'")
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ErrNumeric = errors.New("unable to parse numeric part of quantity")
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ErrSuffix = errors.New("unable to parse quantity's suffix")
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)
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// parseQuantityString is a fast scanner for quantity values.
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func parseQuantityString(str string) (positive bool, value, num, denom, suffix string, err error) {
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positive = true
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pos := 0
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end := len(str)
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// handle leading sign
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if pos < end {
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switch str[0] {
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case '-':
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positive = false
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pos++
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case '+':
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pos++
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}
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}
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// strip leading zeros
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Zeroes:
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for i := pos; ; i++ {
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if i >= end {
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num = "0"
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value = num
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return
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}
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switch str[i] {
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case '0':
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pos++
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default:
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break Zeroes
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}
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}
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// extract the numerator
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Num:
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for i := pos; ; i++ {
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if i >= end {
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num = str[pos:end]
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value = str[0:end]
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return
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}
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switch str[i] {
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case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
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default:
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num = str[pos:i]
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pos = i
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break Num
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}
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}
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// if we stripped all numerator positions, always return 0
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if len(num) == 0 {
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num = "0"
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}
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// handle a denominator
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if pos < end && str[pos] == '.' {
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pos++
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Denom:
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for i := pos; ; i++ {
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if i >= end {
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denom = str[pos:end]
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value = str[0:end]
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return
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}
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switch str[i] {
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case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
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default:
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denom = str[pos:i]
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pos = i
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break Denom
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}
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}
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// TODO: we currently allow 1.G, but we may not want to in the future.
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// if len(denom) == 0 {
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// err = ErrFormatWrong
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// return
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// }
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}
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value = str[0:pos]
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// grab the elements of the suffix
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suffixStart := pos
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for i := pos; ; i++ {
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if i >= end {
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suffix = str[suffixStart:end]
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return
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}
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if !strings.ContainsAny(str[i:i+1], "eEinumkKMGTP") {
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pos = i
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break
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}
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}
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if pos < end {
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switch str[pos] {
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case '-', '+':
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pos++
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}
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}
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Suffix:
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for i := pos; ; i++ {
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if i >= end {
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suffix = str[suffixStart:end]
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return
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}
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switch str[i] {
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case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
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default:
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break Suffix
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}
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}
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// we encountered a non decimal in the Suffix loop, but the last character
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// was not a valid exponent
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err = ErrFormatWrong
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return
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}
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// ParseQuantity turns str into a Quantity, or returns an error.
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func ParseQuantity(str string) (Quantity, error) {
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if len(str) == 0 {
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return Quantity{}, ErrFormatWrong
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}
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if str == "0" {
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return Quantity{Format: DecimalSI, s: str}, nil
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}
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positive, value, num, denom, suf, err := parseQuantityString(str)
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if err != nil {
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return Quantity{}, err
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}
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base, exponent, format, ok := quantitySuffixer.interpret(suffix(suf))
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if !ok {
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return Quantity{}, ErrSuffix
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}
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precision := int32(0)
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scale := int32(0)
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mantissa := int64(1)
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switch format {
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case DecimalExponent, DecimalSI:
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scale = exponent
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precision = maxInt64Factors - int32(len(num)+len(denom))
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case BinarySI:
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scale = 0
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switch {
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case exponent >= 0 && len(denom) == 0:
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// only handle positive binary numbers with the fast path
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mantissa = int64(int64(mantissa) << uint64(exponent))
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// 1Mi (2^20) has ~6 digits of decimal precision, so exponent*3/10 -1 is roughly the precision
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precision = 15 - int32(len(num)) - int32(float32(exponent)*3/10) - 1
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default:
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precision = -1
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}
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}
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if precision >= 0 {
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// if we have a denominator, shift the entire value to the left by the number of places in the
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// denominator
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scale -= int32(len(denom))
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if scale >= int32(Nano) {
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shifted := num + denom
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var value int64
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value, err := strconv.ParseInt(shifted, 10, 64)
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if err != nil {
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return Quantity{}, ErrNumeric
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}
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if result, ok := int64Multiply(value, int64(mantissa)); ok {
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if !positive {
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result = -result
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}
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// if the number is in canonical form, reuse the string
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switch format {
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case BinarySI:
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if exponent%10 == 0 && (value&0x07 != 0) {
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return Quantity{i: int64Amount{value: result, scale: Scale(scale)}, Format: format, s: str}, nil
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}
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default:
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if scale%3 == 0 && !strings.HasSuffix(shifted, "000") && shifted[0] != '0' {
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return Quantity{i: int64Amount{value: result, scale: Scale(scale)}, Format: format, s: str}, nil
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}
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}
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return Quantity{i: int64Amount{value: result, scale: Scale(scale)}, Format: format}, nil
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}
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}
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}
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amount := new(inf.Dec)
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if _, ok := amount.SetString(value); !ok {
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return Quantity{}, ErrNumeric
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}
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// So that no one but us has to think about suffixes, remove it.
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if base == 10 {
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amount.SetScale(amount.Scale() + Scale(exponent).infScale())
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} else if base == 2 {
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// numericSuffix = 2 ** exponent
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numericSuffix := big.NewInt(1).Lsh(bigOne, uint(exponent))
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ub := amount.UnscaledBig()
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amount.SetUnscaledBig(ub.Mul(ub, numericSuffix))
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}
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// Cap at min/max bounds.
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sign := amount.Sign()
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if sign == -1 {
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amount.Neg(amount)
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}
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// This rounds non-zero values up to the minimum representable value, under the theory that
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// if you want some resources, you should get some resources, even if you asked for way too small
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// of an amount. Arguably, this should be inf.RoundHalfUp (normal rounding), but that would have
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// the side effect of rounding values < .5n to zero.
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if v, ok := amount.Unscaled(); v != int64(0) || !ok {
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amount.Round(amount, Nano.infScale(), inf.RoundUp)
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}
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// The max is just a simple cap.
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// TODO: this prevents accumulating quantities greater than int64, for instance quota across a cluster
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if format == BinarySI && amount.Cmp(maxAllowed.Dec) > 0 {
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amount.Set(maxAllowed.Dec)
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}
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if format == BinarySI && amount.Cmp(decOne) < 0 && amount.Cmp(decZero) > 0 {
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// This avoids rounding and hopefully confusion, too.
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format = DecimalSI
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}
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if sign == -1 {
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amount.Neg(amount)
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}
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return Quantity{d: infDecAmount{amount}, Format: format}, nil
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}
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// DeepCopy returns a deep-copy of the Quantity value. Note that the method
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// receiver is a value, so we can mutate it in-place and return it.
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func (q Quantity) DeepCopy() Quantity {
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if q.d.Dec != nil {
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tmp := &inf.Dec{}
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q.d.Dec = tmp.Set(q.d.Dec)
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}
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return q
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}
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// OpenAPISchemaType is used by the kube-openapi generator when constructing
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// the OpenAPI spec of this type.
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//
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// See: https://github.com/kubernetes/kube-openapi/tree/master/pkg/generators
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func (_ Quantity) OpenAPISchemaType() []string { return []string{"string"} }
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// OpenAPISchemaFormat is used by the kube-openapi generator when constructing
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// the OpenAPI spec of this type.
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func (_ Quantity) OpenAPISchemaFormat() string { return "" }
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// CanonicalizeBytes returns the canonical form of q and its suffix (see comment on Quantity).
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//
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// Note about BinarySI:
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// * If q.Format is set to BinarySI and q.Amount represents a non-zero value between
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// -1 and +1, it will be emitted as if q.Format were DecimalSI.
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// * Otherwise, if q.Format is set to BinarySI, fractional parts of q.Amount will be
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// rounded up. (1.1i becomes 2i.)
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func (q *Quantity) CanonicalizeBytes(out []byte) (result, suffix []byte) {
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if q.IsZero() {
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return zeroBytes, nil
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}
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var rounded CanonicalValue
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format := q.Format
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switch format {
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case DecimalExponent, DecimalSI:
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case BinarySI:
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if q.CmpInt64(-1024) > 0 && q.CmpInt64(1024) < 0 {
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// This avoids rounding and hopefully confusion, too.
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format = DecimalSI
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} else {
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var exact bool
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if rounded, exact = q.AsScale(0); !exact {
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// Don't lose precision-- show as DecimalSI
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format = DecimalSI
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}
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}
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default:
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format = DecimalExponent
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}
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// TODO: If BinarySI formatting is requested but would cause rounding, upgrade to
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// one of the other formats.
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switch format {
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case DecimalExponent, DecimalSI:
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number, exponent := q.AsCanonicalBytes(out)
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suffix, _ := quantitySuffixer.constructBytes(10, exponent, format)
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return number, suffix
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default:
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// format must be BinarySI
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number, exponent := rounded.AsCanonicalBase1024Bytes(out)
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suffix, _ := quantitySuffixer.constructBytes(2, exponent*10, format)
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return number, suffix
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}
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}
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// AsInt64 returns a representation of the current value as an int64 if a fast conversion
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// is possible. If false is returned, callers must use the inf.Dec form of this quantity.
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func (q *Quantity) AsInt64() (int64, bool) {
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if q.d.Dec != nil {
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return 0, false
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}
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return q.i.AsInt64()
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}
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// ToDec promotes the quantity in place to use an inf.Dec representation and returns itself.
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func (q *Quantity) ToDec() *Quantity {
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if q.d.Dec == nil {
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q.d.Dec = q.i.AsDec()
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q.i = int64Amount{}
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}
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return q
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}
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// AsDec returns the quantity as represented by a scaled inf.Dec.
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func (q *Quantity) AsDec() *inf.Dec {
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if q.d.Dec != nil {
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return q.d.Dec
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}
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q.d.Dec = q.i.AsDec()
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q.i = int64Amount{}
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return q.d.Dec
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}
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// AsCanonicalBytes returns the canonical byte representation of this quantity as a mantissa
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|
// and base 10 exponent. The out byte slice may be passed to the method to avoid an extra
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// allocation.
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func (q *Quantity) AsCanonicalBytes(out []byte) (result []byte, exponent int32) {
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if q.d.Dec != nil {
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return q.d.AsCanonicalBytes(out)
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}
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return q.i.AsCanonicalBytes(out)
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}
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// IsZero returns true if the quantity is equal to zero.
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func (q *Quantity) IsZero() bool {
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if q.d.Dec != nil {
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return q.d.Dec.Sign() == 0
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}
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return q.i.value == 0
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}
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// Sign returns 0 if the quantity is zero, -1 if the quantity is less than zero, or 1 if the
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// quantity is greater than zero.
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func (q *Quantity) Sign() int {
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if q.d.Dec != nil {
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return q.d.Dec.Sign()
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}
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return q.i.Sign()
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}
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// AsScale returns the current value, rounded up to the provided scale, and returns
|
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// false if the scale resulted in a loss of precision.
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func (q *Quantity) AsScale(scale Scale) (CanonicalValue, bool) {
|
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if q.d.Dec != nil {
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return q.d.AsScale(scale)
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}
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return q.i.AsScale(scale)
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}
|
|
|
|
// RoundUp updates the quantity to the provided scale, ensuring that the value is at
|
|
// least 1. False is returned if the rounding operation resulted in a loss of precision.
|
|
// Negative numbers are rounded away from zero (-9 scale 1 rounds to -10).
|
|
func (q *Quantity) RoundUp(scale Scale) bool {
|
|
if q.d.Dec != nil {
|
|
q.s = ""
|
|
d, exact := q.d.AsScale(scale)
|
|
q.d = d
|
|
return exact
|
|
}
|
|
// avoid clearing the string value if we have already calculated it
|
|
if q.i.scale >= scale {
|
|
return true
|
|
}
|
|
q.s = ""
|
|
i, exact := q.i.AsScale(scale)
|
|
q.i = i
|
|
return exact
|
|
}
|
|
|
|
// Add adds the provide y quantity to the current value. If the current value is zero,
|
|
// the format of the quantity will be updated to the format of y.
|
|
func (q *Quantity) Add(y Quantity) {
|
|
q.s = ""
|
|
if q.d.Dec == nil && y.d.Dec == nil {
|
|
if q.i.value == 0 {
|
|
q.Format = y.Format
|
|
}
|
|
if q.i.Add(y.i) {
|
|
return
|
|
}
|
|
} else if q.IsZero() {
|
|
q.Format = y.Format
|
|
}
|
|
q.ToDec().d.Dec.Add(q.d.Dec, y.AsDec())
|
|
}
|
|
|
|
// Sub subtracts the provided quantity from the current value in place. If the current
|
|
// value is zero, the format of the quantity will be updated to the format of y.
|
|
func (q *Quantity) Sub(y Quantity) {
|
|
q.s = ""
|
|
if q.IsZero() {
|
|
q.Format = y.Format
|
|
}
|
|
if q.d.Dec == nil && y.d.Dec == nil && q.i.Sub(y.i) {
|
|
return
|
|
}
|
|
q.ToDec().d.Dec.Sub(q.d.Dec, y.AsDec())
|
|
}
|
|
|
|
// Cmp returns 0 if the quantity is equal to y, -1 if the quantity is less than y, or 1 if the
|
|
// quantity is greater than y.
|
|
func (q *Quantity) Cmp(y Quantity) int {
|
|
if q.d.Dec == nil && y.d.Dec == nil {
|
|
return q.i.Cmp(y.i)
|
|
}
|
|
return q.AsDec().Cmp(y.AsDec())
|
|
}
|
|
|
|
// CmpInt64 returns 0 if the quantity is equal to y, -1 if the quantity is less than y, or 1 if the
|
|
// quantity is greater than y.
|
|
func (q *Quantity) CmpInt64(y int64) int {
|
|
if q.d.Dec != nil {
|
|
return q.d.Dec.Cmp(inf.NewDec(y, inf.Scale(0)))
|
|
}
|
|
return q.i.Cmp(int64Amount{value: y})
|
|
}
|
|
|
|
// Neg sets quantity to be the negative value of itself.
|
|
func (q *Quantity) Neg() {
|
|
q.s = ""
|
|
if q.d.Dec == nil {
|
|
q.i.value = -q.i.value
|
|
return
|
|
}
|
|
q.d.Dec.Neg(q.d.Dec)
|
|
}
|
|
|
|
// int64QuantityExpectedBytes is the expected width in bytes of the canonical string representation
|
|
// of most Quantity values.
|
|
const int64QuantityExpectedBytes = 18
|
|
|
|
// String formats the Quantity as a string, caching the result if not calculated.
|
|
// String is an expensive operation and caching this result significantly reduces the cost of
|
|
// normal parse / marshal operations on Quantity.
|
|
func (q *Quantity) String() string {
|
|
if len(q.s) == 0 {
|
|
result := make([]byte, 0, int64QuantityExpectedBytes)
|
|
number, suffix := q.CanonicalizeBytes(result)
|
|
number = append(number, suffix...)
|
|
q.s = string(number)
|
|
}
|
|
return q.s
|
|
}
|
|
|
|
// MarshalJSON implements the json.Marshaller interface.
|
|
func (q Quantity) MarshalJSON() ([]byte, error) {
|
|
if len(q.s) > 0 {
|
|
out := make([]byte, len(q.s)+2)
|
|
out[0], out[len(out)-1] = '"', '"'
|
|
copy(out[1:], q.s)
|
|
return out, nil
|
|
}
|
|
result := make([]byte, int64QuantityExpectedBytes, int64QuantityExpectedBytes)
|
|
result[0] = '"'
|
|
number, suffix := q.CanonicalizeBytes(result[1:1])
|
|
// if the same slice was returned to us that we passed in, avoid another allocation by copying number into
|
|
// the source slice and returning that
|
|
if len(number) > 0 && &number[0] == &result[1] && (len(number)+len(suffix)+2) <= int64QuantityExpectedBytes {
|
|
number = append(number, suffix...)
|
|
number = append(number, '"')
|
|
return result[:1+len(number)], nil
|
|
}
|
|
// if CanonicalizeBytes needed more space than our slice provided, we may need to allocate again so use
|
|
// append
|
|
result = result[:1]
|
|
result = append(result, number...)
|
|
result = append(result, suffix...)
|
|
result = append(result, '"')
|
|
return result, nil
|
|
}
|
|
|
|
// UnmarshalJSON implements the json.Unmarshaller interface.
|
|
// TODO: Remove support for leading/trailing whitespace
|
|
func (q *Quantity) UnmarshalJSON(value []byte) error {
|
|
l := len(value)
|
|
if l == 4 && bytes.Equal(value, []byte("null")) {
|
|
q.d.Dec = nil
|
|
q.i = int64Amount{}
|
|
return nil
|
|
}
|
|
if l >= 2 && value[0] == '"' && value[l-1] == '"' {
|
|
value = value[1 : l-1]
|
|
}
|
|
|
|
parsed, err := ParseQuantity(strings.TrimSpace(string(value)))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
// This copy is safe because parsed will not be referred to again.
|
|
*q = parsed
|
|
return nil
|
|
}
|
|
|
|
// NewQuantity returns a new Quantity representing the given
|
|
// value in the given format.
|
|
func NewQuantity(value int64, format Format) *Quantity {
|
|
return &Quantity{
|
|
i: int64Amount{value: value},
|
|
Format: format,
|
|
}
|
|
}
|
|
|
|
// NewMilliQuantity returns a new Quantity representing the given
|
|
// value * 1/1000 in the given format. Note that BinarySI formatting
|
|
// will round fractional values, and will be changed to DecimalSI for
|
|
// values x where (-1 < x < 1) && (x != 0).
|
|
func NewMilliQuantity(value int64, format Format) *Quantity {
|
|
return &Quantity{
|
|
i: int64Amount{value: value, scale: -3},
|
|
Format: format,
|
|
}
|
|
}
|
|
|
|
// NewScaledQuantity returns a new Quantity representing the given
|
|
// value * 10^scale in DecimalSI format.
|
|
func NewScaledQuantity(value int64, scale Scale) *Quantity {
|
|
return &Quantity{
|
|
i: int64Amount{value: value, scale: scale},
|
|
Format: DecimalSI,
|
|
}
|
|
}
|
|
|
|
// Value returns the unscaled value of q rounded up to the nearest integer away from 0.
|
|
func (q *Quantity) Value() int64 {
|
|
return q.ScaledValue(0)
|
|
}
|
|
|
|
// MilliValue returns the value of ceil(q * 1000); this could overflow an int64;
|
|
// if that's a concern, call Value() first to verify the number is small enough.
|
|
func (q *Quantity) MilliValue() int64 {
|
|
return q.ScaledValue(Milli)
|
|
}
|
|
|
|
// ScaledValue returns the value of ceil(q * 10^scale); this could overflow an int64.
|
|
// To detect overflow, call Value() first and verify the expected magnitude.
|
|
func (q *Quantity) ScaledValue(scale Scale) int64 {
|
|
if q.d.Dec == nil {
|
|
i, _ := q.i.AsScaledInt64(scale)
|
|
return i
|
|
}
|
|
dec := q.d.Dec
|
|
return scaledValue(dec.UnscaledBig(), int(dec.Scale()), int(scale.infScale()))
|
|
}
|
|
|
|
// Set sets q's value to be value.
|
|
func (q *Quantity) Set(value int64) {
|
|
q.SetScaled(value, 0)
|
|
}
|
|
|
|
// SetMilli sets q's value to be value * 1/1000.
|
|
func (q *Quantity) SetMilli(value int64) {
|
|
q.SetScaled(value, Milli)
|
|
}
|
|
|
|
// SetScaled sets q's value to be value * 10^scale
|
|
func (q *Quantity) SetScaled(value int64, scale Scale) {
|
|
q.s = ""
|
|
q.d.Dec = nil
|
|
q.i = int64Amount{value: value, scale: scale}
|
|
}
|
|
|
|
// Copy is a convenience function that makes a deep copy for you. Non-deep
|
|
// copies of quantities share pointers and you will regret that.
|
|
func (q *Quantity) Copy() *Quantity {
|
|
if q.d.Dec == nil {
|
|
return &Quantity{
|
|
s: q.s,
|
|
i: q.i,
|
|
Format: q.Format,
|
|
}
|
|
}
|
|
tmp := &inf.Dec{}
|
|
return &Quantity{
|
|
s: q.s,
|
|
d: infDecAmount{tmp.Set(q.d.Dec)},
|
|
Format: q.Format,
|
|
}
|
|
}
|