run.go

   1 /*
   2 goredo -- djb's redo implementation on pure Go
   3 Copyright (C) 2020-2022 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 // Targets runner
  19
  20 package main
  21
  22 import (
  23         "bufio"
  24         "errors"
  25         "flag"
  26         "fmt"
  27         "io"
  28         "log"
  29         "os"
  30         "os/exec"
  31         "path"
  32         "path/filepath"
  33         "strconv"
  34         "strings"
  35         "sync"
  36         "syscall"
  37         "time"
  38
  39         "go.cypherpunks.ru/recfile"
  40         "go.cypherpunks.ru/tai64n/v2"
  41         "golang.org/x/sys/unix"
  42 )
  43
  44 const (
  45         EnvDepFd        = "REDO_DEP_FD"
  46         EnvDirPrefix    = "REDO_DIRPREFIX"
  47         EnvDepCwd       = "REDO_DEP_CWD"
  48         EnvBuildUUID    = "REDO_BUILD_UUID"
  49         EnvStderrPrefix = "REDO_STDERR_PREFIX"
  50         EnvTrace        = "REDO_TRACE"
  51         EnvStderrKeep   = "REDO_LOGS"
  52         EnvStderrSilent = "REDO_SILENT"
  53         EnvNoSync       = "REDO_NO_SYNC"
  54         EnvStopIfMod    = "REDO_STOP_IF_MODIFIED"
  55
  56         RedoDir      = ".redo"
  57         LockSuffix   = ".lock"
  58         DepSuffix    = ".rec"
  59         TmpPrefix    = ".redo."
  60         LogSuffix    = ".log"
  61         LogRecSuffix = ".log-rec"
  62 )
  63
  64 var (
  65         NoSync       = false
  66         StderrKeep   = false
  67         StderrSilent = false
  68         StderrPrefix string
  69         StopIfMod    = false
  70         Jobs         sync.WaitGroup
  71
  72         flagTrace          *bool
  73         flagTraceAll       *bool
  74         flagStderrKeep     *bool
  75         flagStderrSilent   *bool
  76         flagForcedIfchange *bool
  77
  78         TracedAll bool
  79
  80         RunningProcs  = map[int]*os.Process{}
  81         RunningProcsM sync.Mutex
  82
  83         Err1WasTouched = errors.New("$1 was explicitly touched")
  84 )
  85
  86 func init() {
  87         cmdName := CmdName()
  88         if !(cmdName == CmdNameRedo || cmdName == CmdNameRedoIfchange) {
  89                 return
  90         }
  91         flagTrace = flag.Bool("x", false, "trace (sh -x) current targets")
  92         flagTraceAll = flag.Bool("xx", false,
  93                 fmt.Sprintf("trace (sh -x) all targets (%s=1)", EnvTrace))
  94         flagStderrKeep = flag.Bool("k", false,
  95                 fmt.Sprintf("keep job's stderr (%s=1)", EnvStderrKeep))
  96         flagStderrSilent = flag.Bool("s", false,
  97                 fmt.Sprintf("silent, do not print job's stderr (%s=1)", EnvStderrSilent))
  98         flagForcedIfchange = flag.Bool("f", false, "forced redo-ifchange")
  99 }
 100
 101 type RunError struct {
 102         Tgt      string
 103         DoFile   string
 104         Started  *time.Time
 105         Finished *time.Time
 106         Err      error
 107 }
 108
 109 func (e *RunError) Name() string {
 110         var name string
 111         if e.DoFile == "" {
 112                 name = e.Tgt
 113         } else {
 114                 name = fmt.Sprintf("%s (%s)", e.Tgt, e.DoFile)
 115         }
 116         if e.Finished == nil {
 117                 return name
 118         }
 119         return fmt.Sprintf("%s (%.3fs)", name, e.Finished.Sub(*e.Started).Seconds())
 120 }
 121
 122 func (e RunError) Error() string {
 123         return fmt.Sprintf("%s: %s", e.Name(), e.Err)
 124 }
 125
 126 func mkdirs(pth string) error {
 127         if _, err := os.Stat(pth); err == nil {
 128                 return nil
 129         }
 130         return os.MkdirAll(pth, os.FileMode(0777))
 131 }
 132
 133 func isModified(cwd, redoDir, tgt string) (bool, *Inode, string, error) {
 134         fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
 135         if err != nil {
 136                 if os.IsNotExist(err) {
 137                         return false, nil, "", nil
 138                 }
 139                 return false, nil, "", err
 140         }
 141         defer fdDep.Close()
 142         r := recfile.NewReader(fdDep)
 143         var modified bool
 144         var ourInode *Inode
 145         var hshPrev string
 146         for {
 147                 m, err := r.NextMap()
 148                 if err != nil {
 149                         if errors.Is(err, io.EOF) {
 150                                 break
 151                         }
 152                         return false, nil, "", err
 153                 }
 154                 if m["Type"] != DepTypeIfchange || m["Target"] != tgt {
 155                         continue
 156                 }
 157                 fd, err := os.Open(path.Join(cwd, tgt))
 158                 if err != nil {
 159                         if os.IsNotExist(err) {
 160                                 return false, nil, "", nil
 161                         }
 162                         return false, nil, "", err
 163                 }
 164                 ourInode, err = inodeFromFile(fd)
 165                 fd.Close()
 166                 if err != nil {
 167                         return false, nil, "", err
 168                 }
 169                 theirInode, err := inodeFromRec(m)
 170                 if err != nil {
 171                         return false, nil, "", err
 172                 }
 173                 hshPrev = m["Hash"]
 174                 modified = !ourInode.Equals(theirInode)
 175                 break
 176         }
 177         return modified, ourInode, hshPrev, nil
 178 }
 179
 180 func syncDir(dir string) error {
 181         fd, err := os.Open(dir)
 182         if err != nil {
 183                 return err
 184         }
 185         err = fd.Sync()
 186         fd.Close()
 187         return err
 188 }
 189
 190 func runScript(tgtOrig string, errs chan error, traced bool) error {
 191         cwd, tgt := cwdAndTgt(tgtOrig)
 192         redoDir := path.Join(cwd, RedoDir)
 193         if err := mkdirs(redoDir); err != nil {
 194                 return TgtError{tgtOrig, err}
 195         }
 196
 197         shCtx := fmt.Sprintf("sh: %s: cwd:%s", tgtOrig, cwd)
 198         jsToken := jsAcquire(shCtx)
 199         jsNeedsRelease := true
 200         defer func() {
 201                 if jsNeedsRelease {
 202                         jsRelease(shCtx, jsToken)
 203                 }
 204         }()
 205
 206         // Acquire lock
 207         fdLock, err := os.OpenFile(
 208                 path.Join(redoDir, tgt+LockSuffix),
 209                 os.O_WRONLY|os.O_TRUNC|os.O_CREATE,
 210                 os.FileMode(0666),
 211         )
 212         if err != nil {
 213                 return TgtError{tgtOrig, err}
 214         }
 215         flock := unix.Flock_t{
 216                 Type:   unix.F_WRLCK,
 217                 Whence: io.SeekStart,
 218         }
 219         lockRelease := func() {
 220                 tracef(CLock, "LOCK_UN: %s", fdLock.Name())
 221                 flock.Type = unix.F_UNLCK
 222                 if err := unix.FcntlFlock(fdLock.Fd(), unix.F_SETLK, &flock); err != nil {
 223                         log.Fatalln(err)
 224                 }
 225                 fdLock.Close()
 226         }
 227         tracef(CLock, "LOCK_NB: %s", fdLock.Name())
 228
 229         // Waiting for job completion, already taken by someone else
 230         if err = unix.FcntlFlock(fdLock.Fd(), unix.F_SETLK, &flock); err != nil {
 231                 if uintptr(err.(syscall.Errno)) != uintptr(unix.EAGAIN) {
 232                         fdLock.Close()
 233                         return TgtError{tgtOrig, err}
 234                 }
 235                 Jobs.Add(1)
 236                 if err = unix.FcntlFlock(fdLock.Fd(), unix.F_GETLK, &flock); err != nil {
 237                         log.Fatalln(err)
 238                 }
 239                 tracef(CDebug, "waiting: %s (pid=%d)", tgtOrig, flock.Pid)
 240                 if FdStatus != nil {
 241                         if _, err = FdStatus.Write([]byte{StatusWait}); err != nil {
 242                                 log.Fatalln(err)
 243                         }
 244                 }
 245                 go func() {
 246                         defer Jobs.Done()
 247                         tracef(CLock, "LOCK_EX: %s", fdLock.Name())
 248                         if err := unix.FcntlFlock(fdLock.Fd(), unix.F_SETLKW, &flock); err != nil {
 249                                 log.Fatalln(err)
 250                         }
 251                         lockRelease()
 252                         tracef(CDebug, "waiting done: %s", tgtOrig)
 253                         if FdStatus != nil {
 254                                 if _, err = FdStatus.Write([]byte{StatusWaited}); err != nil {
 255                                         log.Fatalln(err)
 256                                 }
 257                         }
 258                         var depInfo *DepInfo
 259                         fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
 260                         if err != nil {
 261                                 if os.IsNotExist(err) {
 262                                         err = errors.New("was not built: no .rec")
 263                                 }
 264                                 goto Finish
 265                         }
 266                         defer fdDep.Close()
 267                         depInfo, err = depRead(fdDep)
 268                         if err != nil {
 269                                 goto Finish
 270                         }
 271                         if depInfo.build != BuildUUID {
 272                                 err = errors.New("was not built: build differs")
 273                         }
 274                 Finish:
 275                         if err != nil {
 276                                 err = TgtError{tgtOrig, err}
 277                                 fdLock.Close()
 278                         }
 279                         errs <- err
 280                 }()
 281                 return nil
 282         }
 283
 284         // Check if target is not modified externally
 285         modified, inodePrev, hshPrev, err := isModified(cwd, redoDir, tgt)
 286         if err != nil {
 287                 lockRelease()
 288                 return TgtError{tgtOrig, err}
 289         }
 290         if modified {
 291                 lockRelease()
 292                 if StopIfMod {
 293                         return fmt.Errorf("%s externally modified", tgtOrig)
 294                 }
 295                 tracef(CWarn, "%s externally modified: not redoing", tgtOrig)
 296                 go func() {
 297                         errs <- nil
 298                 }()
 299                 return nil
 300         }
 301
 302         // Start preparing .rec
 303         fdDep, err := tempfile(redoDir, tgt+DepSuffix)
 304         if err != nil {
 305                 lockRelease()
 306                 return TgtError{tgtOrig, err}
 307         }
 308         fdDepPath := fdDep.Name()
 309         cleanup := func() {
 310                 lockRelease()
 311                 fdDep.Close()
 312                 os.Remove(fdDep.Name())
 313         }
 314         if _, err = recfile.NewWriter(fdDep).WriteFields(
 315                 recfile.Field{Name: "Build", Value: BuildUUID},
 316         ); err != nil {
 317                 cleanup()
 318                 return TgtError{tgtOrig, err}
 319         }
 320
 321         // Find .do
 322         doFile, upLevels, err := findDo(fdDep, cwd, tgt)
 323         if err != nil {
 324                 cleanup()
 325                 return TgtError{tgtOrig, err}
 326         }
 327         if doFile == "" {
 328                 cleanup()
 329                 return TgtError{tgtOrig, errors.New("no .do found")}
 330         }
 331
 332         // Determine basename and DIRPREFIX
 333         doFileRelPath := doFile
 334         ents := strings.Split(cwd, "/")
 335         ents = ents[len(ents)-upLevels:]
 336         dirPrefix := path.Join(ents...)
 337         cwdOrig := cwd
 338         for i := 0; i < upLevels; i++ {
 339                 cwd = path.Join(cwd, "..")
 340                 doFileRelPath = path.Join("..", doFileRelPath)
 341         }
 342         cwd = path.Clean(cwd)
 343         doFilePath := path.Join(cwd, doFile)
 344         basename := tgt
 345         runErr := RunError{Tgt: tgtOrig}
 346         if strings.HasPrefix(doFile, "default.") {
 347                 basename = tgt[:len(tgt)-(len(doFile)-len("default.")-len(".do"))-1]
 348                 runErr.DoFile = doFileRelPath
 349         }
 350
 351         if err = depWrite(fdDep, cwdOrig, doFileRelPath, ""); err != nil {
 352                 cleanup()
 353                 return TgtError{tgtOrig, err}
 354         }
 355         fdDep.Close()
 356         tracef(CWait, "%s", runErr.Name())
 357
 358         // Prepare command line
 359         var cmdName string
 360         var args []string
 361         if err = unix.Access(doFilePath, unix.X_OK); err == nil {
 362                 cmdName = doFilePath
 363                 args = make([]string, 0, 3)
 364         } else {
 365                 cmdName = "/bin/sh"
 366                 if traced || TracedAll {
 367                         args = append(args, "-ex")
 368                 } else {
 369                         args = append(args, "-e")
 370                 }
 371                 args = append(args, doFile)
 372         }
 373
 374         // Temporary file for stdout
 375         fdStdout, err := tempfile(cwdOrig, tgt)
 376         if err != nil {
 377                 cleanup()
 378                 return TgtError{tgtOrig, err}
 379         }
 380         stdoutPath := fdStdout.Name()
 381         fdStdout.Close()
 382         tmpPath := stdoutPath + ".3" // and for $3
 383         tmpPathRel, err := filepath.Rel(cwd, tmpPath)
 384         if err != nil {
 385                 panic(err)
 386         }
 387         args = append(
 388                 args,
 389                 path.Join(dirPrefix, tgt),
 390                 path.Join(dirPrefix, basename),
 391                 tmpPathRel,
 392         )
 393         shCtx = fmt.Sprintf(
 394                 "sh: %s: %s %s cwd:%s dirprefix:%s",
 395                 tgtOrig, cmdName, args, cwd, dirPrefix,
 396         )
 397
 398         cmd := exec.Command(cmdName, args...)
 399         cmd.Dir = cwd
 400         // cmd.Stdin reads from /dev/null by default
 401         cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%d", EnvLevel, Level+1))
 402         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvDirPrefix, dirPrefix))
 403         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvBuildUUID, BuildUUID))
 404
 405         childStderrPrefix := tempsuffix()
 406         cmd.Env = append(cmd.Env, fmt.Sprintf(
 407                 "%s=%s", EnvStderrPrefix, childStderrPrefix,
 408         ))
 409
 410         fdNum := 0
 411         cmd.ExtraFiles = append(cmd.ExtraFiles, FdOODTgts)
 412         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvOODTgtsFd, 3+fdNum))
 413         fdNum++
 414         cmd.ExtraFiles = append(cmd.ExtraFiles, FdOODTgtsLock)
 415         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvOODTgtsLockFd, 3+fdNum))
 416         fdNum++
 417
 418         if FdStatus == nil {
 419                 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=NO", EnvStatusFd))
 420         } else {
 421                 cmd.ExtraFiles = append(cmd.ExtraFiles, FdStatus)
 422                 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvStatusFd, 3+fdNum))
 423                 fdNum++
 424         }
 425
 426         // Preparing stderr
 427         var fdStderr *os.File
 428         if StderrKeep {
 429                 fdStderr, err = os.OpenFile(
 430                         path.Join(redoDir, tgt+LogSuffix),
 431                         os.O_WRONLY|os.O_CREATE|os.O_TRUNC,
 432                         os.FileMode(0666),
 433                 )
 434                 if err != nil {
 435                         cleanup()
 436                         return TgtError{tgtOrig, err}
 437                 }
 438         }
 439         tracef(CDebug, "%s", shCtx)
 440
 441         jsNeedsRelease = false
 442         Jobs.Add(1)
 443         go func() {
 444                 if JSR == nil {
 445                         // infinite jobs
 446                         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=NO", EnvJobs))
 447                 } else {
 448                         cmd.ExtraFiles = append(cmd.ExtraFiles, JSR)
 449                         cmd.ExtraFiles = append(cmd.ExtraFiles, JSW)
 450                         makeFlags := fmt.Sprintf(
 451                                 "%s %s%d,%d", MakeFlags, MakeJSArg, 3+fdNum+0, 3+fdNum+1,
 452                         )
 453                         makeFlags = strings.Trim(makeFlags, " ")
 454                         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", MakeFlagsName, makeFlags))
 455                         fdNum += 2
 456                         cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvJSToken, jsToken))
 457                 }
 458
 459                 if FdStatus != nil {
 460                         if _, err = FdStatus.Write([]byte{StatusRun}); err != nil {
 461                                 log.Fatalln(err)
 462                         }
 463                 }
 464
 465                 defer jsRelease(shCtx, jsToken)
 466
 467                 var finished time.Time
 468                 var exitErr *exec.ExitError
 469                 started := time.Now()
 470                 runErr.Started = &started
 471                 fdStdout, err = os.OpenFile(stdoutPath, os.O_RDWR, os.FileMode(0666))
 472                 if err != nil {
 473                         if fdStderr != nil {
 474                                 fdStderr.Close()
 475                         }
 476                         runErr.Err = err
 477                         errs <- runErr
 478                         return
 479                 }
 480                 cmd.Stdout = fdStdout
 481                 fdDep, err = os.OpenFile(fdDepPath, os.O_WRONLY|os.O_APPEND, os.FileMode(0666))
 482                 if err != nil {
 483                         if fdStderr != nil {
 484                                 fdStderr.Close()
 485                         }
 486                         fdStdout.Close()
 487                         runErr.Err = err
 488                         errs <- runErr
 489                         return
 490                 }
 491                 cmd.ExtraFiles = append(cmd.ExtraFiles, fdDep)
 492                 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvDepFd, 3+fdNum))
 493                 fdNum++
 494                 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvDepCwd, cwd))
 495
 496                 defer func() {
 497                         fdDep.Close()
 498                         fdStdout.Close()
 499                         if fdStderr != nil {
 500                                 fdStderr.Close()
 501                                 logRecPath := path.Join(redoDir, tgt+LogRecSuffix)
 502                                 if fdStderr, err = os.OpenFile(
 503                                         logRecPath,
 504                                         os.O_WRONLY|os.O_CREATE|os.O_TRUNC,
 505                                         os.FileMode(0666),
 506                                 ); err == nil {
 507                                         fields := []recfile.Field{
 508                                                 {Name: "Build", Value: BuildUUID},
 509                                                 {Name: "PPID", Value: strconv.Itoa(os.Getpid())},
 510                                                 {Name: "Cwd", Value: cwd},
 511                                         }
 512                                         if cmd.Process != nil {
 513                                                 fields = append(fields, recfile.Field{
 514                                                         Name: "PID", Value: strconv.Itoa(cmd.Process.Pid),
 515                                                 })
 516                                         }
 517                                         ts := new(tai64n.TAI64N)
 518                                         ts.FromTime(started)
 519                                         fields = append(fields,
 520                                                 recfile.Field{Name: "Started", Value: tai64n.Encode(ts[:])},
 521                                         )
 522                                         ts.FromTime(finished)
 523                                         fields = append(fields,
 524                                                 recfile.Field{Name: "Finished", Value: tai64n.Encode(ts[:])})
 525                                         fields = append(fields, recfile.Field{
 526                                                 Name:  "Duration",
 527                                                 Value: strconv.FormatInt(finished.Sub(started).Nanoseconds(), 10),
 528                                         })
 529                                         fields = append(fields, recfile.Field{Name: "Cmd", Value: cmdName})
 530                                         for _, arg := range args {
 531                                                 fields = append(fields, recfile.Field{Name: "Arg", Value: arg})
 532                                         }
 533                                         for _, env := range cmd.Env {
 534                                                 fields = append(fields, recfile.Field{Name: "Env", Value: env})
 535                                         }
 536                                         if exitErr != nil {
 537                                                 fields = append(fields, recfile.Field{
 538                                                         Name:  "ExitCode",
 539                                                         Value: strconv.Itoa(exitErr.ProcessState.ExitCode()),
 540                                                 })
 541                                         }
 542                                         w := bufio.NewWriter(fdStderr)
 543
 544                                         var depInfo *DepInfo
 545                                         fdDep, err := os.Open(fdDepPath)
 546                                         if err != nil {
 547                                                 goto Err
 548                                         }
 549                                         depInfo, err = depRead(fdDep)
 550                                         fdDep.Close()
 551                                         if err != nil {
 552                                                 goto Err
 553                                         }
 554                                         for _, dep := range depInfo.ifchanges {
 555                                                 fields = append(fields, recfile.Field{
 556                                                         Name:  "Ifchange",
 557                                                         Value: dep["Target"],
 558                                                 })
 559                                         }
 560                                         _, err = recfile.NewWriter(w).WriteFields(fields...)
 561                                         if err != nil {
 562                                                 goto Err
 563                                         }
 564                                         err = w.Flush()
 565                                 Err:
 566                                         if err != nil {
 567                                                 log.Println(err)
 568                                                 os.Remove(logRecPath)
 569                                         }
 570                                         fdStderr.Close()
 571                                 } else {
 572                                         log.Println("can not open", logRecPath, ":", err)
 573                                 }
 574                         }
 575                         lockRelease()
 576                         os.Remove(fdDep.Name())
 577                         os.Remove(fdStdout.Name())
 578                         os.Remove(tmpPath)
 579                         os.Remove(fdLock.Name())
 580                         if FdStatus != nil {
 581                                 if _, err = FdStatus.Write([]byte{StatusDone}); err != nil {
 582                                         log.Fatalln(err)
 583                                 }
 584                         }
 585                         Jobs.Done()
 586                 }()
 587                 stderr, err := cmd.StderrPipe()
 588                 if err != nil {
 589                         runErr.Err = err
 590                         errs <- runErr
 591                         return
 592                 }
 593                 started = time.Now()
 594                 err = cmd.Start()
 595                 if err != nil {
 596                         runErr.Err = err
 597                         errs <- runErr
 598                         return
 599                 }
 600                 RunningProcsM.Lock()
 601                 RunningProcs[cmd.Process.Pid] = cmd.Process
 602                 RunningProcsM.Unlock()
 603                 pid := fmt.Sprintf("[%d]", cmd.Process.Pid)
 604                 tracef(CDebug, "%s runs %s", tgtOrig, pid)
 605
 606                 stderrTerm := make(chan struct{})
 607                 go func() {
 608                         scanner := bufio.NewScanner(stderr)
 609                         var line string
 610                         ts := new(tai64n.TAI64N)
 611                         for scanner.Scan() {
 612                                 line = scanner.Text()
 613                                 if strings.HasPrefix(line, childStderrPrefix) {
 614                                         line = line[len(childStderrPrefix):]
 615                                         os.Stderr.WriteString(StderrPrefix + line + "\n")
 616                                         continue
 617                                 }
 618                                 if fdStderr != nil {
 619                                         ts.FromTime(time.Now())
 620                                         LogMutex.Lock()
 621                                         fmt.Fprintln(fdStderr, tai64n.Encode(ts[:]), line)
 622                                         LogMutex.Unlock()
 623                                 }
 624                                 if StderrSilent {
 625                                         continue
 626                                 }
 627                                 if MyPid == 0 {
 628                                         tracef(CNone, "%s", line)
 629                                 } else {
 630                                         tracef(CNone, "%s %s", pid, line)
 631                                 }
 632                         }
 633                         close(stderrTerm)
 634                 }()
 635
 636                 // Wait for job completion
 637                 <-stderrTerm
 638                 err = cmd.Wait()
 639                 RunningProcsM.Lock()
 640                 delete(RunningProcs, cmd.Process.Pid)
 641                 RunningProcsM.Unlock()
 642                 finished = time.Now()
 643                 runErr.Finished = &finished
 644                 if err != nil {
 645                         exitErr = err.(*exec.ExitError)
 646                         runErr.Err = err
 647                         errs <- runErr
 648                         return
 649                 }
 650
 651                 // Was $1 touched?
 652                 if fd, err := os.Open(path.Join(cwdOrig, tgt)); err == nil {
 653                         if inodePrev == nil {
 654                                 fd.Close()
 655                                 runErr.Err = Err1WasTouched
 656                                 errs <- runErr
 657                                 return
 658                         }
 659                         inode, err := inodeFromFile(fd)
 660                         fd.Close()
 661                         if err != nil {
 662                                 runErr.Err = err
 663                                 errs <- runErr
 664                                 return
 665                         }
 666                         if !inode.Equals(inodePrev) {
 667                                 runErr.Err = Err1WasTouched
 668                                 errs <- runErr
 669                                 return
 670                         }
 671                 }
 672
 673                 if inodePrev != nil {
 674                         if fd, err := os.Open(path.Join(cwdOrig, tgt)); err == nil {
 675                                 inode, err := inodeFromFile(fd)
 676                                 fd.Close()
 677                                 if err == nil && !inode.Equals(inodePrev) {
 678                                         runErr.Err = Err1WasTouched
 679                                         errs <- runErr
 680                                         return
 681                                 }
 682                         }
 683                 }
 684
 685                 // Does it produce both stdout and tmp?
 686                 fiStdout, err := os.Stat(fdStdout.Name())
 687                 if err != nil {
 688                         runErr.Err = err
 689                         errs <- runErr
 690                         return
 691                 }
 692                 tmpExists := false
 693                 _, err = os.Stat(tmpPath)
 694                 if err == nil {
 695                         if fiStdout.Size() > 0 {
 696                                 runErr.Err = errors.New("created both tmp and stdout")
 697                                 errs <- runErr
 698                                 return
 699                         }
 700                         tmpExists = true
 701                 } else if !os.IsNotExist(err) {
 702                         runErr.Err = err
 703                         errs <- runErr
 704                         return
 705                 }
 706
 707                 // Determine what file we must process at last
 708                 var fd *os.File
 709                 if tmpExists {
 710                         fd, err = os.Open(tmpPath)
 711                         if err != nil {
 712                                 goto Finish
 713                         }
 714                         defer fd.Close()
 715                 } else if fiStdout.Size() > 0 {
 716                         fd = fdStdout
 717                 }
 718
 719                 // Do we need to ifcreate it, or ifchange with renaming?
 720                 if fd == nil {
 721                         os.Remove(path.Join(cwdOrig, tgt))
 722                         err = ifcreate(fdDep, tgt)
 723                         if err != nil {
 724                                 goto Finish
 725                         }
 726                 } else {
 727                         var hsh string
 728                         if hshPrev != "" {
 729                                 _, err = fd.Seek(0, io.SeekStart)
 730                                 if err != nil {
 731                                         goto Finish
 732                                 }
 733                                 hsh, err = fileHash(fd)
 734                                 if err != nil {
 735                                         goto Finish
 736                                 }
 737                                 if hsh == hshPrev {
 738                                         tracef(CDebug, "%s has same hash, not renaming", tgtOrig)
 739                                         err = os.Remove(fd.Name())
 740                                         if err != nil {
 741                                                 goto Finish
 742                                         }
 743                                         err = os.Chtimes(path.Join(cwdOrig, tgt), finished, finished)
 744                                         if err != nil {
 745                                                 goto Finish
 746                                         }
 747                                         if !NoSync {
 748                                                 err = syncDir(cwdOrig)
 749                                                 if err != nil {
 750                                                         goto Finish
 751                                                 }
 752                                         }
 753                                         err = depWrite(fdDep, cwdOrig, tgt, hshPrev)
 754                                         if err != nil {
 755                                                 goto Finish
 756                                         }
 757                                         goto RecCommit
 758                                 }
 759                         }
 760                         if !NoSync {
 761                                 err = fd.Sync()
 762                                 if err != nil {
 763                                         goto Finish
 764                                 }
 765                         }
 766                         err = os.Rename(fd.Name(), path.Join(cwdOrig, tgt))
 767                         if err != nil {
 768                                 goto Finish
 769                         }
 770                         if !NoSync {
 771                                 err = syncDir(cwdOrig)
 772                                 if err != nil {
 773                                         goto Finish
 774                                 }
 775                         }
 776                         err = depWrite(fdDep, cwdOrig, tgt, hsh)
 777                         if err != nil {
 778                                 goto Finish
 779                         }
 780                 }
 781
 782         RecCommit:
 783                 // Commit .rec
 784                 if !NoSync {
 785                         err = fdDep.Sync()
 786                         if err != nil {
 787                                 goto Finish
 788                         }
 789                 }
 790                 fdDepPath = path.Join(redoDir, tgt+DepSuffix)
 791                 err = os.Rename(fdDep.Name(), fdDepPath)
 792                 if err != nil {
 793                         goto Finish
 794                 }
 795                 if !NoSync {
 796                         err = syncDir(redoDir)
 797                         if err != nil {
 798                                 goto Finish
 799                         }
 800                 }
 801
 802                 // Post-commit .rec sanitizing
 803                 fdDep.Close()
 804                 if fdDepR, err := os.Open(fdDepPath); err == nil {
 805                         depInfo, err := depRead(fdDepR)
 806                         fdDepR.Close()
 807                         if err != nil {
 808                                 goto Finish
 809                         }
 810                         ifchangeSeen := make(map[string]struct{}, len(depInfo.ifchanges))
 811                         for _, dep := range depInfo.ifchanges {
 812                                 ifchangeSeen[dep["Target"]] = struct{}{}
 813                         }
 814                         for _, dep := range depInfo.ifcreates {
 815                                 if _, exists := ifchangeSeen[dep]; exists {
 816                                         tracef(CWarn, "simultaneous ifcreate and ifchange records: %s", tgt)
 817                                 }
 818                         }
 819                 }
 820
 821         Finish:
 822                 runErr.Err = err
 823                 errs <- runErr
 824         }()
 825         return nil
 826 }
 827
 828 func isOkRun(err error) bool {
 829         if err == nil {
 830                 return true
 831         }
 832         var runErr RunError
 833         if errors.As(err, &runErr) && runErr.Err == nil {
 834                 tracef(CRedo, "%s", runErr.Name())
 835                 return true
 836         }
 837         tracef(CErr, "%s", err)
 838         return false
 839 }