1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
// 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 (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"strings"
"github.com/prometheus/procfs/internal/util"
)
// A NetSockstat contains the output of /proc/net/sockstat{,6} for IPv4 or IPv6,
// respectively.
type NetSockstat struct {
// Used is non-nil for IPv4 sockstat results, but nil for IPv6.
Used *int
Protocols []NetSockstatProtocol
}
// A NetSockstatProtocol contains statistics about a given socket protocol.
// Pointer fields indicate that the value may or may not be present on any
// given protocol.
type NetSockstatProtocol struct {
Protocol string
InUse int
Orphan *int
TW *int
Alloc *int
Mem *int
Memory *int
}
// NetSockstat retrieves IPv4 socket statistics.
func (fs FS) NetSockstat() (*NetSockstat, error) {
return readSockstat(fs.proc.Path("net", "sockstat"))
}
// NetSockstat6 retrieves IPv6 socket statistics.
//
// If IPv6 is disabled on this kernel, the returned error can be checked with
// os.IsNotExist.
func (fs FS) NetSockstat6() (*NetSockstat, error) {
return readSockstat(fs.proc.Path("net", "sockstat6"))
}
// readSockstat opens and parses a NetSockstat from the input file.
func readSockstat(name string) (*NetSockstat, error) {
// This file is small and can be read with one syscall.
b, err := util.ReadFileNoStat(name)
if err != nil {
// Do not wrap this error so the caller can detect os.IsNotExist and
// similar conditions.
return nil, err
}
stat, err := parseSockstat(bytes.NewReader(b))
if err != nil {
return nil, fmt.Errorf("failed to read sockstats from %q: %w", name, err)
}
return stat, nil
}
// parseSockstat reads the contents of a sockstat file and parses a NetSockstat.
func parseSockstat(r io.Reader) (*NetSockstat, error) {
var stat NetSockstat
s := bufio.NewScanner(r)
for s.Scan() {
// Expect a minimum of a protocol and one key/value pair.
fields := strings.Split(s.Text(), " ")
if len(fields) < 3 {
return nil, fmt.Errorf("malformed sockstat line: %q", s.Text())
}
// The remaining fields are key/value pairs.
kvs, err := parseSockstatKVs(fields[1:])
if err != nil {
return nil, fmt.Errorf("error parsing sockstat key/value pairs from %q: %w", s.Text(), err)
}
// The first field is the protocol. We must trim its colon suffix.
proto := strings.TrimSuffix(fields[0], ":")
switch proto {
case "sockets":
// Special case: IPv4 has a sockets "used" key/value pair that we
// embed at the top level of the structure.
used := kvs["used"]
stat.Used = &used
default:
// Parse all other lines as individual protocols.
nsp := parseSockstatProtocol(kvs)
nsp.Protocol = proto
stat.Protocols = append(stat.Protocols, nsp)
}
}
if err := s.Err(); err != nil {
return nil, err
}
return &stat, nil
}
// parseSockstatKVs parses a string slice into a map of key/value pairs.
func parseSockstatKVs(kvs []string) (map[string]int, error) {
if len(kvs)%2 != 0 {
return nil, errors.New("odd number of fields in key/value pairs")
}
// Iterate two values at a time to gather key/value pairs.
out := make(map[string]int, len(kvs)/2)
for i := 0; i < len(kvs); i += 2 {
vp := util.NewValueParser(kvs[i+1])
out[kvs[i]] = vp.Int()
if err := vp.Err(); err != nil {
return nil, err
}
}
return out, nil
}
// parseSockstatProtocol parses a NetSockstatProtocol from the input kvs map.
func parseSockstatProtocol(kvs map[string]int) NetSockstatProtocol {
var nsp NetSockstatProtocol
for k, v := range kvs {
// Capture the range variable to ensure we get unique pointers for
// each of the optional fields.
v := v
switch k {
case "inuse":
nsp.InUse = v
case "orphan":
nsp.Orphan = &v
case "tw":
nsp.TW = &v
case "alloc":
nsp.Alloc = &v
case "mem":
nsp.Mem = &v
case "memory":
nsp.Memory = &v
}
}
return nsp
}
|
