netdata/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

//go:build linux
// +build linux

package systemdunits

import (
    "fmt"
    "regexp"
    "strconv"
)

func (s *SystemdUnits) collect() (map[string]int64, error) {
    conn, err := s.getConnection()
    if err != nil {
        return nil, err
    }

    if s.systemdVersion == 0 {
        ver, err := s.getSystemdVersion(conn)
        if err != nil {
            s.closeConnection()
            return nil, err
        }
        s.systemdVersion = ver
    }

    mx := make(map[string]int64)

    if err := s.collectUnits(mx, conn); err != nil {
        s.closeConnection()
        return nil, err
    }

    if s.CollectUnitFiles && len(s.IncludeUnitFiles) > 0 {
        if err := s.collectUnitFiles(mx, conn); err != nil {
            s.closeConnection()
            return mx, err
        }
    }

    return mx, nil
}

func (s *SystemdUnits) getConnection() (systemdConnection, error) {
    if s.conn == nil {
        conn, err := s.client.connect()
        if err != nil {
            return nil, fmt.Errorf("error on creating a connection: %v", err)
        }
        s.conn = conn
    }
    return s.conn, nil
}

func (s *SystemdUnits) closeConnection() {
    if s.conn != nil {
        s.conn.Close()
        s.conn = nil
    }
}

var reVersion = regexp.MustCompile(`[0-9][0-9][0-9]`)

const versionProperty = "Version"

func (s *SystemdUnits) getSystemdVersion(conn systemdConnection) (int, error) {
    s.Debugf("calling function 'GetManagerProperty'")
    version, err := conn.GetManagerProperty(versionProperty)
    if err != nil {
        return 0, fmt.Errorf("error on getting '%s' manager property: %v", versionProperty, err)
    }

    s.Debugf("systemd version: %s", version)

    major := reVersion.FindString(version)
    if major == "" {
        return 0, fmt.Errorf("couldn't parse systemd version string '%s'", version)
    }

    ver, err := strconv.Atoi(major)
    if err != nil {
        return 0, fmt.Errorf("couldn't parse systemd version string '%s': %v", version, err)
    }

    return ver, nil
}