podman

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// Copyright 2013-2022 Frank Schroeder. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package properties
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import (
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	"fmt"
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	"runtime"
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)
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type parser struct {
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	lex *lexer
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}
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func parse(input string) (properties *Properties, err error) {
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	p := &parser{lex: lex(input)}
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	defer p.recover(&err)
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	properties = NewProperties()
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	key := ""
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	comments := []string{}
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	for {
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		token := p.expectOneOf(itemComment, itemKey, itemEOF)
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		switch token.typ {
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		case itemEOF:
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			goto done
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		case itemComment:
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			comments = append(comments, token.val)
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			continue
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		case itemKey:
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			key = token.val
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			if _, ok := properties.m[key]; !ok {
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				properties.k = append(properties.k, key)
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			}
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		}
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		token = p.expectOneOf(itemValue, itemEOF)
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		if len(comments) > 0 {
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			properties.c[key] = comments
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			comments = []string{}
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		}
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		switch token.typ {
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		case itemEOF:
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			properties.m[key] = ""
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			goto done
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		case itemValue:
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			properties.m[key] = token.val
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		}
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	}
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done:
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	return properties, nil
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}
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func (p *parser) errorf(format string, args ...interface{}) {
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	format = fmt.Sprintf("properties: Line %d: %s", p.lex.lineNumber(), format)
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	panic(fmt.Errorf(format, args...))
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}
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func (p *parser) expectOneOf(expected ...itemType) (token item) {
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	token = p.lex.nextItem()
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	for _, v := range expected {
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		if token.typ == v {
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			return token
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		}
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	}
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	p.unexpected(token)
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	panic("unexpected token")
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}
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func (p *parser) unexpected(token item) {
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	p.errorf(token.String())
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}
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// recover is the handler that turns panics into returns from the top level of Parse.
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func (p *parser) recover(errp *error) {
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	e := recover()
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	if e != nil {
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		if _, ok := e.(runtime.Error); ok {
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			panic(e)
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		}
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		*errp = e.(error)
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	}
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}
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