status.go

   1 /*
   2 goredo -- redo implementation on pure Go
   3 Copyright (C) 2020 Sergey Matveev <stargrave@stargrave.org>
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, version 3 of the License.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 package main
  19
  20 import (
  21         "flag"
  22         "fmt"
  23         "os"
  24         "strings"
  25 )
  26
  27 const (
  28         EnvStatusFd = "REDO_STATUS_FD"
  29         EnvNoStatus = "REDO_NO_STATUS"
  30
  31         StatusRun = iota
  32         StatusDone
  33         StatusWait
  34         StatusWaited
  35 )
  36
  37 var (
  38         FdStatus *os.File
  39
  40         flagNoStatus = flag.Bool("no-status", false, "disable statusline (REDO_NO_STATUS=1)")
  41 )
  42
  43 func statusInit() {
  44         if *flagNoStatus {
  45                 return
  46         }
  47         if v := os.Getenv(EnvNoStatus); v == "1" {
  48                 return
  49         }
  50         if v := os.Getenv(EnvStatusFd); v != "" {
  51                 if v == "NO" {
  52                         return
  53                 }
  54                 FdStatus = mustParseFd(v, EnvStatusFd)
  55                 return
  56         }
  57         var r *os.File
  58         var err error
  59         r, FdStatus, err = os.Pipe()
  60         if err != nil {
  61                 panic(err)
  62         }
  63         go func() {
  64                 running := 0
  65                 waiting := 0
  66                 done := 0
  67                 var out string
  68                 outLenPrev := 0
  69                 buf := make([]byte, 1)
  70                 var n int
  71                 for {
  72                         n, err = r.Read(buf)
  73                         if err != nil || n != 1 {
  74                                 break
  75                         }
  76                         switch buf[0] {
  77                         case StatusRun:
  78                                 running++
  79                         case StatusDone:
  80                                 running--
  81                                 done++
  82                         case StatusWait:
  83                                 waiting++
  84                         case StatusWaited:
  85                                 waiting--
  86                         }
  87                         if NoColor {
  88                                 out = fmt.Sprintf(
  89                                         "\rrun: %d wait: %d done: %d\r",
  90                                         running, waiting, done,
  91                                 )
  92                         } else {
  93                                 out = fmt.Sprintf(
  94                                         "\rrun: %s%d%s wait: %s%d%s done: %s%d%s\r",
  95                                         CRedo, running, CReset,
  96                                         CWait, waiting, CReset,
  97                                         CJS, done, CReset,
  98                                 )
  99                         }
 100                         if len(out) < outLenPrev {
 101                                 outLenPrev = len(out)
 102                                 out += strings.Repeat(" ", outLenPrev-len(out))
 103                         } else {
 104                                 outLenPrev = len(out)
 105                         }
 106                         LogMutex.Lock()
 107                         os.Stderr.WriteString(out)
 108                         LogMutex.Unlock()
 109                 }
 110         }()
 111 }