Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/inputs/snmp_trap/netsnmp.go

@@ -0,0 +1,91 @@
+package snmp_trap
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"os/exec"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/influxdata/telegraf/config"
+	"github.com/influxdata/telegraf/internal"
+	"github.com/influxdata/telegraf/internal/snmp"
+)
+
+type execer func(config.Duration, string, ...string) ([]byte, error)
+
+func realExecCmd(timeout config.Duration, arg0 string, args ...string) ([]byte, error) {
+	cmd := exec.Command(arg0, args...)
+	var out bytes.Buffer
+	cmd.Stdout = &out
+	err := internal.RunTimeout(cmd, time.Duration(timeout))
+	if err != nil {
+		return nil, err
+	}
+	return out.Bytes(), nil
+}
+
+type netsnmpTranslator struct {
+	// Each translator has its own cache and each plugin instance has
+	// its own translator. This is different than the snmp plugin
+	// which has one global cache.
+	//
+	// We may want to change snmp_trap to
+	// have a global cache although it's not as important for
+	// snmp_trap to be global because there is usually only one
+	// instance, while it's common to configure many snmp instances.
+	cacheLock sync.Mutex
+	cache     map[string]snmp.MibEntry
+	execCmd   execer
+	timeout   config.Duration
+}
+
+func (s *netsnmpTranslator) lookup(oid string) (e snmp.MibEntry, err error) {
+	s.cacheLock.Lock()
+	defer s.cacheLock.Unlock()
+	var ok bool
+	if e, ok = s.cache[oid]; !ok {
+		// cache miss.  exec snmptranslate
+		e, err = s.snmptranslate(oid)
+		if err == nil {
+			s.cache[oid] = e
+		}
+		return e, err
+	}
+	return e, nil
+}
+
+func (s *netsnmpTranslator) snmptranslate(oid string) (e snmp.MibEntry, err error) {
+	var out []byte
+	out, err = s.execCmd(s.timeout, "snmptranslate", "-Td", "-Ob", "-m", "all", oid)
+
+	if err != nil {
+		return e, err
+	}
+
+	scanner := bufio.NewScanner(bytes.NewBuffer(out))
+	ok := scanner.Scan()
+	if err = scanner.Err(); !ok && err != nil {
+		return e, err
+	}
+
+	e.OidText = scanner.Text()
+
+	i := strings.Index(e.OidText, "::")
+	if i == -1 {
+		return e, errors.New("not found")
+	}
+	e.MibName = e.OidText[:i]
+	e.OidText = e.OidText[i+2:]
+	return e, nil
+}
+
+func newNetsnmpTranslator(timeout config.Duration) *netsnmpTranslator {
+	return &netsnmpTranslator{
+		execCmd: realExecCmd,
+		cache:   make(map[string]snmp.MibEntry),
+		timeout: timeout,
+	}
+}