Refactor package structure

Builds but not tested

pkg/archive/nodelist.go

@@ -0,0 +1,175 @@
+// Copyright (C) 2022 NHR@FAU, University Erlangen-Nuremberg.
+// All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+package archive
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/ClusterCockpit/cc-backend/pkg/log"
+)
+
+type NodeList [][]interface {
+	consume(input string) (next string, ok bool)
+}
+
+func (nl *NodeList) Contains(name string) bool {
+	var ok bool
+	for _, term := range *nl {
+		str := name
+		for _, expr := range term {
+			str, ok = expr.consume(str)
+			if !ok {
+				break
+			}
+		}
+
+		if ok && str == "" {
+			return true
+		}
+	}
+
+	return false
+}
+
+type NLExprString string
+
+func (nle NLExprString) consume(input string) (next string, ok bool) {
+	str := string(nle)
+	if strings.HasPrefix(input, str) {
+		return strings.TrimPrefix(input, str), true
+	}
+	return "", false
+}
+
+type NLExprIntRanges []NLExprIntRange
+
+func (nles NLExprIntRanges) consume(input string) (next string, ok bool) {
+	for _, nle := range nles {
+		if next, ok := nle.consume(input); ok {
+			return next, ok
+		}
+	}
+	return "", false
+}
+
+type NLExprIntRange struct {
+	start, end int64
+	zeroPadded bool
+	digits     int
+}
+
+func (nle NLExprIntRange) consume(input string) (next string, ok bool) {
+	if !nle.zeroPadded || nle.digits < 1 {
+		log.Error("node list: only zero-padded ranges are allowed")
+		return "", false
+	}
+
+	if len(input) < nle.digits {
+		return "", false
+	}
+
+	numerals, rest := input[:nle.digits], input[nle.digits:]
+	for len(numerals) > 1 && numerals[0] == '0' {
+		numerals = numerals[1:]
+	}
+
+	x, err := strconv.ParseInt(numerals, 10, 32)
+	if err != nil {
+		return "", false
+	}
+
+	if nle.start <= x && x <= nle.end {
+		return rest, true
+	}
+
+	return "", false
+}
+
+func ParseNodeList(raw string) (NodeList, error) {
+	isLetter := func(r byte) bool { return ('a' <= r && r <= 'z') || ('A' <= r && r <= 'Z') }
+	isDigit := func(r byte) bool { return '0' <= r && r <= '9' }
+
+	rawterms := []string{}
+	prevterm := 0
+	for i := 0; i < len(raw); i++ {
+		if raw[i] == '[' {
+			for i < len(raw) && raw[i] != ']' {
+				i++
+			}
+			if i == len(raw) {
+				return nil, fmt.Errorf("node list: unclosed '['")
+			}
+		} else if raw[i] == ',' {
+			rawterms = append(rawterms, raw[prevterm:i])
+			prevterm = i + 1
+		}
+	}
+	if prevterm != len(raw) {
+		rawterms = append(rawterms, raw[prevterm:])
+	}
+
+	nl := NodeList{}
+	for _, rawterm := range rawterms {
+		exprs := []interface {
+			consume(input string) (next string, ok bool)
+		}{}
+		for i := 0; i < len(rawterm); i++ {
+			c := rawterm[i]
+			if isLetter(c) || isDigit(c) {
+				j := i
+				for j < len(rawterm) && (isLetter(rawterm[j]) || isDigit(rawterm[j])) {
+					j++
+				}
+				exprs = append(exprs, NLExprString(rawterm[i:j]))
+				i = j - 1
+			} else if c == '[' {
+				end := strings.Index(rawterm[i:], "]")
+				if end == -1 {
+					return nil, fmt.Errorf("node list: unclosed '['")
+				}
+
+				parts := strings.Split(rawterm[i+1:i+end], ",")
+				nles := NLExprIntRanges{}
+				for _, part := range parts {
+					minus := strings.Index(part, "-")
+					if minus == -1 {
+						return nil, fmt.Errorf("node list: no '-' found inside '[...]'")
+					}
+
+					s1, s2 := part[0:minus], part[minus+1:]
+					if len(s1) != len(s2) || len(s1) == 0 {
+						return nil, fmt.Errorf("node list: %#v and %#v are not of equal length or of length zero", s1, s2)
+					}
+
+					x1, err := strconv.ParseInt(s1, 10, 32)
+					if err != nil {
+						return nil, fmt.Errorf("node list: %w", err)
+					}
+					x2, err := strconv.ParseInt(s2, 10, 32)
+					if err != nil {
+						return nil, fmt.Errorf("node list: %w", err)
+					}
+
+					nles = append(nles, NLExprIntRange{
+						start:      x1,
+						end:        x2,
+						digits:     len(s1),
+						zeroPadded: true,
+					})
+				}
+
+				exprs = append(exprs, nles)
+				i += end
+			} else {
+				return nil, fmt.Errorf("node list: invalid character: %#v", rune(c))
+			}
+		}
+		nl = append(nl, exprs)
+	}
+
+	return nl, nil
+}