Initial commit

vendor/github.com/prometheus/procfs/diskstats.go

@@ -0,0 +1,81 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/prometheus/procfs/iostats"
+)
+
+const (
+	diskstatsFilename = "diskstats"
+	statFormat        = "%d %d %s %d %d %d %d %d %d %d %d %d %d %d %d %d %d %d"
+)
+
+// NewDiskstats reads the diskstats file and returns
+// an array of Diskstats (one per line/device)
+func NewDiskstats() ([]iostats.IODeviceStats, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewDiskstats()
+}
+
+// NewDiskstats reads the diskstats file and returns
+// an array of Diskstats (one per line/device)
+func (fs FS) NewDiskstats() ([]iostats.IODeviceStats, error) {
+	file, err := os.Open(fs.Path(diskstatsFilename))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	diskstats := []iostats.IODeviceStats{}
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		d := &iostats.IODeviceStats{}
+		count, err := fmt.Sscanf(scanner.Text(), statFormat,
+			&d.MajorNumber,
+			&d.MinorNumber,
+			&d.DeviceName,
+			&d.ReadIOs,
+			&d.ReadMerges,
+			&d.ReadSectors,
+			&d.ReadTicks,
+			&d.WriteIOs,
+			&d.WriteMerges,
+			&d.WriteSectors,
+			&d.WriteTicks,
+			&d.IOsInProgress,
+			&d.IOsTotalTicks,
+			&d.WeightedIOTicks,
+			&d.DiscardIOs,
+			&d.DiscardMerges,
+			&d.DiscardSectors,
+			&d.DiscardTicks)
+		if err != nil && err != io.EOF {
+			return diskstats, err
+		}
+		if count == 14 || count == 18 {
+			diskstats = append(diskstats, *d)
+		}
+	}
+	return diskstats, nil
+}