Temporarily add go-agentx (w/ fixes to lexico ordering)

go-agentx/value/oid.go

@@ -0,0 +1,103 @@
+// Copyright 2018 The agentx authors
+// Licensed under the LGPLv3 with static-linking exception.
+// See LICENCE file for details.
+
+package value
+
+import (
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// OID defines an OID.
+type OID []uint32
+
+// ParseOID parses the provided string and returns a valid oid. If one of the
+// subidentifers canot be parsed to an uint32, the function will panic.
+func ParseOID(text string) (OID, error) {
+	var result OID
+
+	parts := strings.Split(text, ".")
+	for _, part := range parts {
+		subidentifier, err := strconv.ParseUint(part, 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("parse uint [%s]: %w", part, err)
+		}
+		result = append(result, uint32(subidentifier))
+	}
+
+	return result, nil
+}
+
+// MustParseOID works like ParseOID expect it panics on a parsing error.
+func MustParseOID(text string) OID {
+	result, err := ParseOID(text)
+	if err != nil {
+		panic(err)
+	}
+	return result
+}
+
+// First returns the first n subidentifiers as a new oid.
+func (o OID) First(count int) OID {
+	return o[:count]
+}
+
+// CommonPrefix compares the oid with the provided one and
+// returns a new oid containing all matching prefix subidentifiers.
+func (o OID) CommonPrefix(other OID) OID {
+	matchCount := 0
+
+	for index, subidentifier := range o {
+		if index >= len(other) || subidentifier != other[index] {
+			break
+		}
+		matchCount++
+	}
+
+	return o[:matchCount]
+}
+
+// CompareOIDs returns an integer comparing two OIDs lexicographically.
+// The result will be 0 if oid1 == oid2, -1 if oid1 < oid2, +1 if oid1 > oid2.
+func CompareOIDs(oid1, oid2 OID) int {
+	if oid2 != nil {
+		oid1Length := len(oid1)
+		oid2Length := len(oid2)
+		for i := 0; i < oid1Length && i < oid2Length; i++ {
+			if oid1[i] < oid2[i] {
+				return -1
+			}
+			if oid1[i] > oid2[i] {
+				return 1
+			}
+		}
+		if oid1Length == oid2Length {
+			return 0
+		} else if oid1Length < oid2Length {
+			return -1
+		} else {
+			return 1
+		}
+	}
+	return 1
+}
+
+// SortOIDs performs sorting of the OID list.
+func SortOIDs(oids []OID) {
+	sort.Slice(oids, func(i, j int) bool {
+		return CompareOIDs(oids[i], oids[j]) == -1
+	})
+}
+
+func (o OID) String() string {
+	var parts []string
+
+	for _, subidentifier := range o {
+		parts = append(parts, fmt.Sprintf("%d", subidentifier))
+	}
+
+	return strings.Join(parts, ".")
+}