Update swagger to 0.20.1 (#8010)

* update swagger to 0.20.1

* fiw swagger version for validate

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

@@ -0,0 +1,91 @@
+// Copyright 2019 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 (
+	"fmt"
+	"io/ioutil"
+	"strconv"
+	"strings"
+)
+
+// For the proc file format details,
+// see https://elixir.bootlin.com/linux/v4.17/source/net/core/net-procfs.c#L162
+// and https://elixir.bootlin.com/linux/v4.17/source/include/linux/netdevice.h#L2810.
+
+// SoftnetEntry contains a single row of data from /proc/net/softnet_stat
+type SoftnetEntry struct {
+	// Number of processed packets
+	Processed uint
+	// Number of dropped packets
+	Dropped uint
+	// Number of times processing packets ran out of quota
+	TimeSqueezed uint
+}
+
+// GatherSoftnetStats reads /proc/net/softnet_stat, parse the relevant columns,
+// and then return a slice of SoftnetEntry's.
+func (fs FS) GatherSoftnetStats() ([]SoftnetEntry, error) {
+	data, err := ioutil.ReadFile(fs.proc.Path("net/softnet_stat"))
+	if err != nil {
+		return nil, fmt.Errorf("error reading softnet %s: %s", fs.proc.Path("net/softnet_stat"), err)
+	}
+
+	return parseSoftnetEntries(data)
+}
+
+func parseSoftnetEntries(data []byte) ([]SoftnetEntry, error) {
+	lines := strings.Split(string(data), "\n")
+	entries := make([]SoftnetEntry, 0)
+	var err error
+	const (
+		expectedColumns = 11
+	)
+	for _, line := range lines {
+		columns := strings.Fields(line)
+		width := len(columns)
+		if width == 0 {
+			continue
+		}
+		if width != expectedColumns {
+			return []SoftnetEntry{}, fmt.Errorf("%d columns were detected, but %d were expected", width, expectedColumns)
+		}
+		var entry SoftnetEntry
+		if entry, err = parseSoftnetEntry(columns); err != nil {
+			return []SoftnetEntry{}, err
+		}
+		entries = append(entries, entry)
+	}
+
+	return entries, nil
+}
+
+func parseSoftnetEntry(columns []string) (SoftnetEntry, error) {
+	var err error
+	var processed, dropped, timeSqueezed uint64
+	if processed, err = strconv.ParseUint(columns[0], 16, 32); err != nil {
+		return SoftnetEntry{}, fmt.Errorf("Unable to parse column 0: %s", err)
+	}
+	if dropped, err = strconv.ParseUint(columns[1], 16, 32); err != nil {
+		return SoftnetEntry{}, fmt.Errorf("Unable to parse column 1: %s", err)
+	}
+	if timeSqueezed, err = strconv.ParseUint(columns[2], 16, 32); err != nil {
+		return SoftnetEntry{}, fmt.Errorf("Unable to parse column 2: %s", err)
+	}
+	return SoftnetEntry{
+		Processed:    uint(processed),
+		Dropped:      uint(dropped),
+		TimeSqueezed: uint(timeSqueezed),
+	}, nil
+}