main.go

   1 package main
   2
   3 import (
   4         "bufio"
   5         "flag"
   6         "fmt"
   7         "log"
   8         "os"
   9         "os/exec"
  10         "strconv"
  11         "strings"
  12         "time"
  13
  14         "github.com/dustin/go-humanize"
  15 )
  16
  17 var (
  18         MyPID string = strconv.Itoa(os.Getpid())
  19         CPU   string = "?"
  20         Freq  string = "?"
  21         Mem   string = "?"
  22         ARC   string = "?"
  23         Swap  string = "?"
  24         Flags string = "?"
  25         IOs   string = "?"
  26         Net   string = "?"
  27 )
  28
  29 func piper(c chan []string, name string, args ...string) error {
  30         cmd := exec.Command(name, args...)
  31         r, err := cmd.StdoutPipe()
  32         if err != nil {
  33                 return err
  34         }
  35         err = cmd.Start()
  36         if err != nil {
  37                 return err
  38         }
  39         scanner := bufio.NewScanner(r)
  40         for scanner.Scan() {
  41                 cols := strings.Fields(scanner.Text())
  42                 if len(cols) > 0 {
  43                         c <- cols
  44                 }
  45         }
  46         if err = scanner.Err(); err != nil {
  47                 cmd.Process.Kill()
  48                 cmd.Wait()
  49                 return err
  50         }
  51         return nil
  52 }
  53
  54 func bg(cmd string, args ...string) chan []string {
  55         c := make(chan []string)
  56         go func() {
  57                 for {
  58                         err := piper(c, cmd, args...)
  59                         if err != nil {
  60                                 log.Println("error:", cmd, ":", err)
  61                         }
  62                         time.Sleep(time.Second)
  63                 }
  64         }()
  65         return c
  66 }
  67
  68 func top() {
  69         for cols := range bg("top", "-b", "-d", "infinity", "-p", MyPID, "-s", "5", "infinity") {
  70                 switch cols[0] {
  71                 case "CPU:":
  72                         CPU = strings.ReplaceAll(fmt.Sprintf(
  73                                 "%s sys:%s int:%s n:%s",
  74                                 cols[1], cols[5], cols[7], cols[3],
  75                         ), "%", "")
  76                 case "Mem:":
  77                         Mem = strings.ReplaceAll(strings.Join(cols[1:], " "), ",", "")
  78                 case "ARC:":
  79                         ARC = cols[1]
  80                 case "Swap:":
  81                         if len(cols) >= 5 && cols[4] == "Used," {
  82                                 Swap = cols[3] + " Swap "
  83                         } else {
  84                                 Swap = ""
  85                         }
  86                 }
  87         }
  88 }
  89
  90 func iostat() {
  91         var stats []string
  92         for cols := range bg("iostat", "-d", "-w", "1", "-x") {
  93                 if cols[0] == "device" {
  94                         IOs = strings.Join(stats, " ")
  95                         stats = nil
  96                         continue
  97                 }
  98                 if len(cols) < 4 || (cols[1] == "0" && cols[2] == "0") {
  99                         continue
 100                 }
 101                 stats = append(stats, fmt.Sprintf("%s:%s/%s", cols[0], cols[1], cols[2]))
 102         }
 103 }
 104
 105 func netstat() {
 106         for cols := range bg("netstat", "-I", "bridge0", "-n", "1") {
 107                 if _, err := strconv.Atoi(cols[0]); err != nil {
 108                         continue
 109                 }
 110                 ibps, err := strconv.Atoi(cols[3])
 111                 if err != nil {
 112                         continue
 113                 }
 114                 obps, err := strconv.Atoi(cols[6])
 115                 if err != nil {
 116                         continue
 117                 }
 118                 Net = fmt.Sprintf(
 119                         "%s/%s %s / %s",
 120                         cols[0], cols[4],
 121                         humanize.IBytes(uint64(ibps)),
 122                         humanize.IBytes(uint64(obps)),
 123                 )
 124         }
 125 }
 126
 127 func freq() {
 128         for cols := range bg("sysctl", "-n", "dev.cpu.0.freq") {
 129                 raw, err := strconv.Atoi(cols[0])
 130                 if err != nil {
 131                         continue
 132                 }
 133                 Freq = fmt.Sprintf("%.1fG", float64(raw)/1000)
 134         }
 135 }
 136
 137 func flagfiles() {
 138         ents, err := os.ReadDir("/tmp/stargrave-flags")
 139         if err != nil {
 140                 log.Println(err)
 141                 return
 142         }
 143         fs := make([]string, 0, len(ents))
 144         for _, ent := range ents {
 145                 fs = append(fs, ent.Name())
 146         }
 147         Flags = strings.Join(fs, " ")
 148 }
 149
 150 func main() {
 151         xsetroot := flag.Bool("xsetroot", false, "Call xsetroot")
 152         flag.Parse()
 153         go func() {
 154                 for {
 155                         flagfiles()
 156                         time.Sleep(20 * time.Second)
 157                 }
 158         }()
 159         go top()
 160         go freq()
 161         go iostat()
 162         go netstat()
 163         var now time.Time
 164         var status string
 165         var cmd *exec.Cmd
 166         for {
 167                 now = time.Now()
 168                 status = fmt.Sprintf(
 169                         "[%s]  [%s]  [%s %s]  [%s%s %s ARC]  [%s] %s",
 170                         IOs, Net, CPU, Freq, Swap, Mem, ARC, Flags,
 171                         now.Format("2006-01-02 15:04:05"),
 172                 )
 173                 if *xsetroot {
 174                         cmd = exec.Command("xsetroot", "-name", status)
 175                         cmd.Run()
 176                 } else {
 177                         fmt.Println(status)
 178                 }
 179                 time.Sleep(time.Second)
 180         }
 181 }