2 goredo -- redo implementation on pure Go
3 Copyright (C) 2020 Sergey Matveev <stargrave@stargrave.org>
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.
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.
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/>.
38 "go.cypherpunks.ru/recfile"
39 "golang.org/x/sys/unix"
43 EnvDepFd = "REDO_DEP_FD"
44 EnvDirPrefix = "REDO_DIRPREFIX"
45 EnvBuildUUID = "REDO_BUILD_UUID"
46 EnvStderrPrefix = "REDO_STDERR_PREFIX"
47 EnvTrace = "REDO_TRACE"
48 EnvStderrKeep = "REDO_LOGS"
49 EnvStderrSilent = "REDO_SILENT"
50 EnvNoSync = "REDO_NO_SYNC"
61 StderrKeep bool = false
62 StderrSilent bool = false
66 flagTrace = flag.Bool("x", false, fmt.Sprintf("trace current target (sh -x) (set %s=1 for all others)", EnvTrace))
67 flagStderrKeep = flag.Bool("logs", false, fmt.Sprintf("keep job's stderr (%s=1)", EnvStderrKeep))
68 flagStderrSilent = flag.Bool("silent", false, fmt.Sprintf("do not print job's stderr (%s=1)", EnvStderrSilent))
79 func (e RunErr) Unwrap() error { return e.Err }
81 func (e *RunErr) Name() string {
86 name = fmt.Sprintf("%s (%s)", e.Tgt, e.DoFile)
88 if e.Finished == nil {
91 return fmt.Sprintf("%s (%fsec)", name, e.Finished.Sub(*e.Started).Seconds())
94 func (e RunErr) Error() string {
95 return fmt.Sprintf("%s: %s", e.Name(), e.Err)
98 func mkdirs(pth string) error {
99 if _, err := os.Stat(pth); err == nil {
102 return os.MkdirAll(pth, os.FileMode(0777))
105 func tempsuffix() string {
106 return strconv.FormatInt((time.Now().UnixNano()+int64(os.Getpid()))&0xFFFFFFFF, 16)
109 func tempfile(dir, prefix string) (*os.File, error) {
110 // It respects umask, unlike ioutil.TempFile
111 name := path.Join(dir, TmpPrefix+prefix+"."+tempsuffix())
112 return os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, os.FileMode(0666))
115 func isModified(cwd, redoDir, tgt string) (bool, string, error) {
116 fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
118 if os.IsNotExist(err) {
119 return false, "", nil
121 return false, "", err
124 r := recfile.NewReader(fdDep)
127 m, err := r.NextMap()
132 return false, "", err
134 if m["Target"] != tgt {
137 fd, err := os.Open(path.Join(cwd, tgt))
139 if os.IsNotExist(err) {
140 return false, "", nil
142 return false, "", err
145 ourTs, err = fileCtime(fd)
147 return false, "", err
149 if ourTs != m["Ctime"] {
150 return true, ourTs, nil
154 return false, ourTs, nil
157 func syncDir(dir string) error {
158 fd, err := os.Open(dir)
167 func runScript(tgtOrig string, errs chan error, traced bool) error {
168 cwd, tgt := cwdAndTgt(tgtOrig)
169 redoDir := path.Join(cwd, RedoDir)
170 if err := mkdirs(redoDir); err != nil {
171 return TgtErr{tgtOrig, err}
175 fdLock, err := os.OpenFile(
176 path.Join(redoDir, tgt+LockSuffix),
177 os.O_WRONLY|os.O_TRUNC|os.O_CREATE,
181 return TgtErr{tgtOrig, err}
183 lockRelease := func() {
184 trace(CLock, "LOCK_UN: %s", fdLock.Name())
185 unix.Flock(int(fdLock.Fd()), unix.LOCK_UN)
188 trace(CLock, "LOCK_NB: %s", fdLock.Name())
190 // Waiting for job completion, already taken by someone else
191 if err = unix.Flock(int(fdLock.Fd()), unix.LOCK_EX|unix.LOCK_NB); err != nil {
192 if uintptr(err.(syscall.Errno)) != uintptr(unix.EWOULDBLOCK) {
194 return TgtErr{tgtOrig, err}
197 trace(CDebug, "waiting: %s", tgtOrig)
199 FdStatus.Write([]byte{StatusWait})
203 trace(CLock, "LOCK_EX: %s", fdLock.Name())
204 unix.Flock(int(fdLock.Fd()), unix.LOCK_EX)
206 trace(CDebug, "waiting done: %s", tgtOrig)
208 FdStatus.Write([]byte{StatusWaited})
211 fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
213 if os.IsNotExist(err) {
214 err = errors.New("was not built: no .dep")
219 depInfo, err = depRead(fdDep)
223 if depInfo.build != BuildUUID {
224 err = errors.New("was not built: build differs")
228 err = TgtErr{tgtOrig, err}
235 // Check if target is not modified externally
236 modified, tsPrev, err := isModified(cwd, redoDir, tgt)
239 return TgtErr{tgtOrig, err}
242 trace(CWarn, "%s externally modified: not redoing", tgtOrig)
250 // Start preparing .dep
251 fdDep, err := tempfile(redoDir, tgt+DepSuffix)
254 return TgtErr{tgtOrig, err}
259 os.Remove(fdDep.Name())
261 if _, err = recfile.NewWriter(fdDep).WriteFields(
262 recfile.Field{Name: "Build", Value: BuildUUID},
265 return TgtErr{tgtOrig, err}
269 doFile, upLevels, err := findDo(fdDep, cwd, tgt)
272 return TgtErr{tgtOrig, err}
276 return TgtErr{tgtOrig, errors.New("no .do found")}
279 // Determine basename and DIRPREFIX
280 ents := strings.Split(cwd, "/")
281 ents = ents[len(ents)-upLevels:]
282 dirPrefix := path.Join(ents...)
284 for i := 0; i < upLevels; i++ {
285 cwd = path.Join(cwd, "..")
287 cwd = path.Clean(cwd)
288 doFilePath := path.Join(cwd, doFile)
290 runErr := RunErr{Tgt: tgtOrig}
291 if strings.HasPrefix(doFile, "default.") {
292 basename = tgt[:len(tgt)-(len(doFile)-len("default.")-len(".do"))-1]
293 runErr.DoFile = doFile
296 if err = writeDep(fdDep, cwd, doFile); err != nil {
298 return TgtErr{tgtOrig, err}
300 trace(CWait, "%s", runErr.Name())
302 // Prepare command line
305 if err = unix.Access(doFilePath, unix.X_OK); err == nil {
307 args = make([]string, 0, 3)
311 args = append(args, "-ex")
313 args = append(args, "-e")
315 args = append(args, doFile)
318 // Temporary file for stdout
319 fdStdout, err := tempfile(cwd, tgt)
322 return TgtErr{tgtOrig, err}
324 tmpPath := fdStdout.Name() + ".3" // and for $3
325 args = append(args, tgt, basename, path.Base(tmpPath))
327 cmd := exec.Command(cmdName, args...)
329 cmd.Stdout = fdStdout
330 cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%d", EnvLevel, Level+1))
331 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvDirPrefix, dirPrefix))
332 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvBuildUUID, BuildUUID))
334 childStderrPrefix := tempsuffix()
335 cmd.Env = append(cmd.Env, fmt.Sprintf(
336 "%s=%s", EnvStderrPrefix, childStderrPrefix,
340 cmd.ExtraFiles = append(cmd.ExtraFiles, fdDep)
341 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvDepFd, 3+fdNum))
345 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=NO", EnvStatusFd))
347 cmd.ExtraFiles = append(cmd.ExtraFiles, FdStatus)
348 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvStatusFd, 3+fdNum))
354 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=NO", EnvJSFd))
356 cmd.ExtraFiles = append(cmd.ExtraFiles, JSR)
357 cmd.ExtraFiles = append(cmd.ExtraFiles, JSW)
358 cmd.Env = append(cmd.Env, fmt.Sprintf(
359 "%s=%d,%d", EnvJSFd, 3+fdNum+0, 3+fdNum+1,
365 stderr, err := cmd.StderrPipe()
369 var fdStderr *os.File
371 fdStderr, err = os.OpenFile(
372 path.Join(redoDir, tgt+LogSuffix),
373 os.O_WRONLY|os.O_CREATE,
378 return TgtErr{tgtOrig, err}
382 shCtx := fmt.Sprintf("sh: %s: %s %s [%s]", tgtOrig, cmdName, args, cwd)
383 trace(CDebug, "%s", shCtx)
389 FdStatus.Write([]byte{StatusRun})
399 os.Remove(fdDep.Name())
400 os.Remove(fdStdout.Name())
402 os.Remove(fdLock.Name())
404 FdStatus.Write([]byte{StatusDone})
408 started := time.Now()
409 runErr.Started = &started
416 pid := fmt.Sprintf("[%d]", cmd.Process.Pid)
417 trace(CDebug, "%s runs %s", tgtOrig, pid)
419 stderrTerm := make(chan struct{}, 0)
421 scanner := bufio.NewScanner(stderr)
425 line = scanner.Text()
426 if strings.HasPrefix(line, childStderrPrefix) {
427 line = line[len(childStderrPrefix):]
428 os.Stderr.WriteString(StderrPrefix + line + "\n")
434 fmt.Fprintf(fdStderr, "@%s %s\n", hex.EncodeToString(ts[:]), line)
441 trace(CNone, "%s", line)
443 trace(CNone, "%s %s", pid, line)
449 // Wait for job completion
452 finished := time.Now()
453 runErr.Finished = &finished
461 if fd, err := os.Open(path.Join(cwdOrig, tgt)); err == nil {
462 ts, err := fileCtime(fd)
464 if err == nil && ts != tsPrev {
465 runErr.Err = errors.New("$1 was explicitly touched")
472 // Does it produce both stdout and tmp?
473 fiStdout, err := os.Stat(fdStdout.Name())
480 _, err = os.Stat(tmpPath)
482 if fiStdout.Size() > 0 {
483 runErr.Err = errors.New("created both tmp and stdout")
488 } else if !os.IsNotExist(err) {
494 // Determine what file we must process at last
497 fd, err = os.Open(tmpPath)
502 } else if fiStdout.Size() > 0 {
506 // Do we need to ifcreate it, of ifchange with renaming?
508 err = ifcreate(fdDep, tgt)
519 err = os.Rename(fd.Name(), path.Join(cwdOrig, tgt))
524 err = syncDir(cwdOrig)
529 err = writeDep(fdDep, cwdOrig, tgt)
542 err = os.Rename(fdDep.Name(), path.Join(redoDir, tgt+DepSuffix))
547 err = syncDir(redoDir)
559 func isOkRun(err error) bool {
563 if err, ok := err.(RunErr); ok && err.Err == nil {
564 trace(CRedo, "%s", err.Name())
567 trace(CErr, "%s", err)