use sys/unix package instead of syscall (#1340)

According to the golang docs, the syscall package is deprecated.
https://golang.org/pkg/syscall
This updates collectors to use the x/sys/unix package instead.
Also updates the vendored x/sys/unix module to latest.

Signed-off-by: Paul Gier <pgier@redhat.com>

collector/filesystem_linux.go

@@ -22,10 +22,10 @@ import (
 	"os"
 	"strings"
 	"sync"
-	"syscall"
 	"time"
 
 	"github.com/prometheus/common/log"
+	"golang.org/x/sys/unix"
 )
 
 const (
@@ -70,9 +70,8 @@ func (c *filesystemCollector) GetStats() ([]filesystemStats, error) {
 		success := make(chan struct{})
 		go stuckMountWatcher(labels.mountPoint, success)
 
-		buf := new(syscall.Statfs_t)
-		err = syscall.Statfs(rootfsFilePath(labels.mountPoint), buf)
-
+		buf := new(unix.Statfs_t)
+		err = unix.Statfs(rootfsFilePath(labels.mountPoint), buf)
 		stuckMountsMtx.Lock()
 		close(success)
 		// If the mount has been marked as stuck, unmark it and log it's recovery.

collector/hwmon_linux.go

@@ -23,10 +23,10 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
-	"syscall"
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
+	"golang.org/x/sys/unix"
 )
 
 var (
@@ -86,9 +86,9 @@ func sysReadFile(file string) ([]byte, error) {
 	// Go's ioutil.ReadFile implementation to poll forever.
 	//
 	// Since we either want to read data or bail immediately, do the simplest
-	// possible read using syscall directly.
+	// possible read using system call directly.
 	b := make([]byte, 128)
-	n, err := syscall.Read(int(f.Fd()), b)
+	n, err := unix.Read(int(f.Fd()), b)
 	if err != nil {
 		return nil, err
 	}

collector/sysctl_bsd.go

@@ -18,7 +18,6 @@ package collector
 
 import (
 	"fmt"
-	"syscall"
 	"unsafe"
 
 	"github.com/prometheus/client_golang/prometheus"
@@ -98,16 +97,16 @@ func (b bsdSysctl) getStructTimeval() (float64, error) {
 		return 0, err
 	}
 
-	if len(raw) != int(unsafe.Sizeof(syscall.Timeval{})) {
+	if len(raw) != int(unsafe.Sizeof(unix.Timeval{})) {
 		// Shouldn't get here.
 		return 0, fmt.Errorf(
 			"length of bytes received from sysctl (%d) does not match expected bytes (%d)",
 			len(raw),
-			unsafe.Sizeof(syscall.Timeval{}),
+			unsafe.Sizeof(unix.Timeval{}),
 		)
 	}
 
-	tv := *(*syscall.Timeval)(unsafe.Pointer(&raw[0]))
+	tv := *(*unix.Timeval)(unsafe.Pointer(&raw[0]))
 
 	// This conversion maintains the usec precision.  Using the time
 	// package did not.

collector/timex.go

@@ -18,9 +18,9 @@ package collector
 
 import (
 	"fmt"
-	"syscall"
 
 	"github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/sys/unix"
 )
 
 const (
@@ -156,9 +156,9 @@ func NewTimexCollector() (Collector, error) {
 func (c *timexCollector) Update(ch chan<- prometheus.Metric) error {
 	var syncStatus float64
 	var divisor float64
-	var timex = new(syscall.Timex)
+	var timex = new(unix.Timex)
 
-	status, err := syscall.Adjtimex(timex)
+	status, err := unix.Adjtimex(timex)
 	if err != nil {
 		return fmt.Errorf("failed to retrieve adjtimex stats: %v", err)
 	}