runtime: use FindCommon from c/common

it detects conmon-rs.

[NO NEW TESTS NEEDED] no functionalities added.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

libpod/runtime.go

@@ -2,15 +2,11 @@ package libpod
 
 import (
 	"bufio"
-	"bytes"
 	"context"
 	"errors"
 	"fmt"
 	"os"
-	"os/exec"
 	"path/filepath"
-	"regexp"
-	"strconv"
 	"strings"
 	"sync"
 	"syscall"
@@ -44,17 +40,6 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-const (
-	// conmonMinMajorVersion is the major version required for conmon.
-	conmonMinMajorVersion = 2
-
-	// conmonMinMinorVersion is the minor version required for conmon.
-	conmonMinMinorVersion = 0
-
-	// conmonMinPatchVersion is the sub-minor version required for conmon.
-	conmonMinPatchVersion = 24
-)
-
 // A RuntimeOption is a functional option which alters the Runtime created by
 // NewRuntime
 type RuntimeOption func(*Runtime) error
@@ -308,7 +293,7 @@ func getLockManager(runtime *Runtime) (lock.Manager, error) {
 // Sets up containers/storage, state store, OCI runtime
 func makeRuntime(runtime *Runtime) (retErr error) {
 	// Find a working conmon binary
-	cPath, err := findConmon(runtime.config.Engine.ConmonPath)
+	cPath, err := runtime.config.FindConmon()
 	if err != nil {
 		return err
 	}
@@ -670,102 +655,6 @@ func makeRuntime(runtime *Runtime) (retErr error) {
 	return nil
 }
 
-// findConmon iterates over conmonPaths and returns the path
-// to the first conmon binary with a new enough version. If none is found,
-// we try to do a path lookup of "conmon".
-func findConmon(conmonPaths []string) (string, error) {
-	foundOutdatedConmon := false
-	for _, path := range conmonPaths {
-		stat, err := os.Stat(path)
-		if err != nil {
-			continue
-		}
-		if stat.IsDir() {
-			continue
-		}
-		if err := probeConmon(path); err != nil {
-			logrus.Warnf("Conmon at %s invalid: %v", path, err)
-			foundOutdatedConmon = true
-			continue
-		}
-		logrus.Debugf("Using conmon: %q", path)
-		return path, nil
-	}
-
-	// Search the $PATH as last fallback
-	if path, err := exec.LookPath("conmon"); err == nil {
-		if err := probeConmon(path); err != nil {
-			logrus.Warnf("Conmon at %s is invalid: %v", path, err)
-			foundOutdatedConmon = true
-		} else {
-			logrus.Debugf("Using conmon from $PATH: %q", path)
-			return path, nil
-		}
-	}
-
-	if foundOutdatedConmon {
-		return "", fmt.Errorf(
-			"please update to v%d.%d.%d or later: %w",
-			conmonMinMajorVersion, conmonMinMinorVersion, conmonMinPatchVersion, define.ErrConmonOutdated)
-	}
-
-	return "", fmt.Errorf(
-		"could not find a working conmon binary (configured options: %v): %w",
-		conmonPaths, define.ErrInvalidArg)
-}
-
-// probeConmon calls conmon --version and verifies it is a new enough version for
-// the runtime expectations the container engine currently has.
-func probeConmon(conmonBinary string) error {
-	cmd := exec.Command(conmonBinary, "--version")
-	var out bytes.Buffer
-	cmd.Stdout = &out
-	err := cmd.Run()
-	if err != nil {
-		return err
-	}
-	r := regexp.MustCompile(`^conmon version (?P<Major>\d+).(?P<Minor>\d+).(?P<Patch>\d+)`)
-
-	matches := r.FindStringSubmatch(out.String())
-	if len(matches) != 4 {
-		return fmt.Errorf("%v: %w", define.ErrConmonVersionFormat, err)
-	}
-	major, err := strconv.Atoi(matches[1])
-	if err != nil {
-		return fmt.Errorf("%v: %w", define.ErrConmonVersionFormat, err)
-	}
-	if major < conmonMinMajorVersion {
-		return define.ErrConmonOutdated
-	}
-	if major > conmonMinMajorVersion {
-		return nil
-	}
-
-	minor, err := strconv.Atoi(matches[2])
-	if err != nil {
-		return fmt.Errorf("%v: %w", define.ErrConmonVersionFormat, err)
-	}
-	if minor < conmonMinMinorVersion {
-		return define.ErrConmonOutdated
-	}
-	if minor > conmonMinMinorVersion {
-		return nil
-	}
-
-	patch, err := strconv.Atoi(matches[3])
-	if err != nil {
-		return fmt.Errorf("%v: %w", define.ErrConmonVersionFormat, err)
-	}
-	if patch < conmonMinPatchVersion {
-		return define.ErrConmonOutdated
-	}
-	if patch > conmonMinPatchVersion {
-		return nil
-	}
-
-	return nil
-}
-
 // TmpDir gets the current Libpod temporary files directory.
 func (r *Runtime) TmpDir() (string, error) {
 	if !r.valid {