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/>.
37 "go.cypherpunks.ru/recfile"
38 "golang.org/x/sys/unix"
42 EnvDepFd = "REDO_DEP_FD"
43 EnvDirPrefix = "REDO_DIRPREFIX"
44 EnvBuildUUID = "REDO_BUILD_UUID"
45 EnvStderrPrefix = "REDO_STDERR_PREFIX"
46 EnvTrace = "REDO_TRACE"
47 EnvStderrKeep = "REDO_LOGS"
48 EnvStderrSilent = "REDO_SILENT"
49 EnvNoSync = "REDO_NO_SYNC"
61 StderrKeep bool = false
62 StderrSilent bool = false
65 flagTrace = flag.Bool("x", false, "trace current target (sh -x) (set REDO_TRACE=1 for others too)")
66 flagStderrKeep = flag.Bool("logs", false, "keep job's stderr (REDO_LOGS=1)")
67 flagStderrSilent = flag.Bool("silent", false, "do not print job's stderr (REDO_SILENT=1)")
78 func (e RunErr) Unwrap() error { return e.Err }
80 func (e *RunErr) Name() string {
85 name = fmt.Sprintf("%s (%s)", e.Tgt, e.DoFile)
87 if e.Finished == nil {
90 return fmt.Sprintf("%s (%fsec)", name, e.Finished.Sub(*e.Started).Seconds())
93 func (e RunErr) Error() string {
94 return fmt.Sprintf("%s: %s", e.Name(), e.Err)
97 func mkdirs(pth string) error {
98 if _, err := os.Stat(pth); err == nil {
101 return os.MkdirAll(pth, os.FileMode(0777))
104 func tempsuffix() string {
105 return strconv.FormatInt((time.Now().UnixNano()+int64(os.Getpid()))&0xFFFFFFFF, 16)
108 func tempfile(dir, prefix string) (*os.File, error) {
109 // It respects umask, unlike ioutil.TempFile
110 name := path.Join(dir, TmpPrefix+prefix+"."+tempsuffix())
111 return os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, os.FileMode(0666))
114 func isModified(cwd, redoDir, tgt string) (bool, error) {
115 fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
117 if os.IsNotExist(err) {
123 r := recfile.NewReader(fdDep)
125 m, err := r.NextMap()
132 if m["Target"] != tgt {
135 fd, err := os.Open(path.Join(cwd, tgt))
137 if os.IsNotExist(err) {
143 ourTs, err := fileCtime(fd)
147 if ourTs != m["Ctime"] {
155 func syncDir(dir string) error {
156 fd, err := os.Open(dir)
165 func runScript(tgtOrig string, errs chan error) error {
166 cwd, tgt := cwdAndTgt(tgtOrig)
167 redoDir := path.Join(cwd, RedoDir)
168 if err := mkdirs(redoDir); err != nil {
169 return TgtErr{tgtOrig, err}
173 fdLock, err := os.OpenFile(
174 path.Join(redoDir, tgt+LockSuffix),
175 os.O_WRONLY|os.O_TRUNC|os.O_CREATE,
179 return TgtErr{tgtOrig, err}
181 lockRelease := func() {
182 trace(CLock, "LOCK_UN: %s", fdLock.Name())
183 unix.Flock(int(fdLock.Fd()), unix.LOCK_UN)
186 trace(CLock, "LOCK_NB: %s", fdLock.Name())
188 // Waiting for job completion, already taken by someone else
189 if err = unix.Flock(int(fdLock.Fd()), unix.LOCK_EX|unix.LOCK_NB); err != nil {
190 if uintptr(err.(syscall.Errno)) != uintptr(unix.EWOULDBLOCK) {
192 return TgtErr{tgtOrig, err}
194 trace(CDebug, "waiting: %s", tgtOrig)
198 trace(CLock, "LOCK_EX: %s", fdLock.Name())
199 unix.Flock(int(fdLock.Fd()), unix.LOCK_EX)
201 trace(CDebug, "waiting done: %s", tgtOrig)
203 fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
205 if os.IsNotExist(err) {
206 err = errors.New("was not built")
210 builtNow, _, err = isBuiltNow(fdDep)
215 err = errors.New("was not built")
219 err = TgtErr{tgtOrig, err}
226 // Check if target is not modified externally
227 modified, err := isModified(cwd, redoDir, tgt)
230 return TgtErr{tgtOrig, err}
233 trace(CWarn, "%s externally modified: not redoing", tgtOrig)
236 return TgtErr{tgtOrig, err}
239 // Start preparing .dep
240 fdDep, err := tempfile(redoDir, tgt+DepSuffix)
243 return TgtErr{tgtOrig, err}
248 os.Remove(fdDep.Name())
250 if _, err = recfile.NewWriter(fdDep).WriteFields(
251 recfile.Field{Name: "Build", Value: BuildUUID},
254 return TgtErr{tgtOrig, err}
258 doFile, upLevels, err := findDo(fdDep, cwd, tgt)
261 return TgtErr{tgtOrig, err}
265 return TgtErr{tgtOrig, errors.New("no .do found")}
267 if err = writeDep(fdDep, cwd, doFile); err != nil {
269 return TgtErr{tgtOrig, err}
272 // Determine basename and DIRPREFIX
273 ents := strings.Split(cwd, "/")
274 ents = ents[len(ents)-upLevels:]
275 dirPrefix := path.Join(ents...)
277 for i := 0; i < upLevels; i++ {
278 cwd = path.Join(cwd, "..")
280 cwd = path.Clean(cwd)
282 runErr := RunErr{Tgt: tgtOrig}
283 if strings.HasPrefix(doFile, "default.") {
284 basename = tgt[:len(tgt)-(len(doFile)-len("default.")-len(".do"))-1]
285 runErr.DoFile = doFile
287 trace(CWait, "%s", runErr.Name())
288 doFile = path.Base(doFile)
290 // Prepare command line
293 if err = unix.Access(path.Join(cwd, doFile), unix.X_OK); err == nil {
294 // Ordinary executable file
296 args = make([]string, 0, 3)
298 fd, err := os.Open(path.Join(cwd, doFile))
301 return TgtErr{tgtOrig, err}
303 buf := make([]byte, 512)
304 n, err := fd.Read(buf)
307 return TgtErr{tgtOrig, err}
309 if n > 3 && string(buf[:3]) == "#!/" {
311 t := string(buf[2:n])
312 nlIdx := strings.Index(t, "\n")
315 return TgtErr{tgtOrig, errors.New("not fully read shebang")}
317 args = strings.Split(t[:nlIdx], " ")
318 cmdName, args = args[0], args[1:]
323 args = append(args, "-ex")
325 args = append(args, "-e")
328 args = append(args, doFile)
331 // Temporary file for stdout
332 fdStdout, err := tempfile(cwd, tgt)
335 return TgtErr{tgtOrig, err}
337 tmpPath := fdStdout.Name() + ".3" // and for $3
338 args = append(args, tgt, basename, path.Base(tmpPath))
340 cmd := exec.Command(cmdName, args...)
342 cmd.Stdout = fdStdout
343 cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%d", EnvLevel, Level+1))
344 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvDirPrefix, dirPrefix))
345 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvBuildUUID, BuildUUID))
346 childStderrPrefix := tempsuffix()
347 cmd.Env = append(cmd.Env, fmt.Sprintf(
348 "%s=%s", EnvStderrPrefix, childStderrPrefix,
351 cmd.ExtraFiles = append(cmd.ExtraFiles, fdDep)
353 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvDepFd, 3+fdNum))
357 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=NO", EnvJSFd))
359 cmd.ExtraFiles = append(cmd.ExtraFiles, JSR)
360 cmd.ExtraFiles = append(cmd.ExtraFiles, JSW)
361 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d,%d", EnvJSFd, 3+fdNum+0, 3+fdNum+1))
366 stderr, err := cmd.StderrPipe()
370 var fdStderr *os.File
372 fdStderr, err = os.OpenFile(
373 path.Join(redoDir, tgt+LogSuffix),
374 os.O_WRONLY|os.O_CREATE,
379 return TgtErr{tgtOrig, err}
383 shCtx := fmt.Sprintf("sh: %s: %s %s [%s]", tgtOrig, cmdName, args, cwd)
384 trace(CDebug, "%s", shCtx)
397 os.Remove(fdDep.Name())
398 os.Remove(fdStdout.Name())
400 os.Remove(fdLock.Name())
403 started := time.Now()
404 runErr.Started = &started
411 pid := fmt.Sprintf("[%d]", cmd.Process.Pid)
412 trace(CDebug, "%s runs %s", tgtOrig, pid)
414 stderrTerm := make(chan struct{}, 0)
416 scanner := bufio.NewScanner(stderr)
420 line = scanner.Text()
421 if strings.HasPrefix(line, childStderrPrefix) {
422 line = line[len(childStderrPrefix):]
423 os.Stderr.WriteString(StderrPrefix + line + "\n")
428 fmt.Fprintf(fdStderr, "@%s %s\n", hex.EncodeToString(ts[:]), line)
434 trace(CNone, "%s", line)
436 trace(CNone, "%s %s", pid, line)
442 // Wait for job completion
445 finished := time.Now()
446 runErr.Finished = &finished
453 // Does it produce both stdout and tmp?
454 fiStdout, err := os.Stat(fdStdout.Name())
461 _, err = os.Stat(tmpPath)
463 if fiStdout.Size() > 0 {
464 runErr.Err = errors.New("created both tmp and stdout")
469 } else if !os.IsNotExist(err) {
475 // Determine what file we must process at last
478 fd, err = os.Open(tmpPath)
483 } else if fiStdout.Size() > 0 {
487 // Do we need to ifcreate it, of ifchange with renaming?
489 err = ifcreate(fdDep, tgt)
500 err = os.Rename(fd.Name(), path.Join(cwdOrig, tgt))
505 err = syncDir(cwdOrig)
510 err = writeDep(fdDep, cwdOrig, tgt)
523 err = os.Rename(fdDep.Name(), path.Join(redoDir, tgt+DepSuffix))
528 err = syncDir(redoDir)