cubefs

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// Copyright 2019 The Prometheus 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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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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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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package util
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import (
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	"strconv"
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)
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// TODO(mdlayher): util packages are an anti-pattern and this should be moved
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// somewhere else that is more focused in the future.
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// A ValueParser enables parsing a single string into a variety of data types
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// in a concise and safe way. The Err method must be invoked after invoking
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// any other methods to ensure a value was successfully parsed.
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type ValueParser struct {
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	v   string
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	err error
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}
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// NewValueParser creates a ValueParser using the input string.
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func NewValueParser(v string) *ValueParser {
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	return &ValueParser{v: v}
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}
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// Int interprets the underlying value as an int and returns that value.
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func (vp *ValueParser) Int() int { return int(vp.int64()) }
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// PInt64 interprets the underlying value as an int64 and returns a pointer to
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// that value.
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func (vp *ValueParser) PInt64() *int64 {
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	if vp.err != nil {
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		return nil
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	}
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	v := vp.int64()
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	return &v
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}
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// int64 interprets the underlying value as an int64 and returns that value.
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// TODO: export if/when necessary.
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func (vp *ValueParser) int64() int64 {
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	if vp.err != nil {
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		return 0
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	}
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	// A base value of zero makes ParseInt infer the correct base using the
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	// string's prefix, if any.
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	const base = 0
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	v, err := strconv.ParseInt(vp.v, base, 64)
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	if err != nil {
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		vp.err = err
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		return 0
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	}
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	return v
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}
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// PUInt64 interprets the underlying value as an uint64 and returns a pointer to
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// that value.
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func (vp *ValueParser) PUInt64() *uint64 {
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	if vp.err != nil {
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		return nil
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	}
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	// A base value of zero makes ParseInt infer the correct base using the
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	// string's prefix, if any.
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	const base = 0
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	v, err := strconv.ParseUint(vp.v, base, 64)
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	if err != nil {
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		vp.err = err
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		return nil
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	}
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	return &v
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}
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// Err returns the last error, if any, encountered by the ValueParser.
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func (vp *ValueParser) Err() error {
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	return vp.err
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}
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