diff options
Diffstat (limited to 'vendor/github.com/prometheus/procfs/net_sockstat.go')
-rw-r--r-- | vendor/github.com/prometheus/procfs/net_sockstat.go | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/vendor/github.com/prometheus/procfs/net_sockstat.go b/vendor/github.com/prometheus/procfs/net_sockstat.go new file mode 100644 index 000000000..f91ef5523 --- /dev/null +++ b/vendor/github.com/prometheus/procfs/net_sockstat.go @@ -0,0 +1,163 @@ +// 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: %v", 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: %v", 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 +} |