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