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(tgt string, errs chan error) error {
167 cwd, tgt := cwdAndTgt(tgt)
168 redoDir := path.Join(cwd, RedoDir)
169 if err := mkdirs(redoDir); err != nil {
170 return TgtErr{tgtOrig, err}
174 fdLock, err := os.OpenFile(
175 path.Join(redoDir, tgt+LockSuffix),
176 os.O_WRONLY|os.O_TRUNC|os.O_CREATE,
180 return TgtErr{tgtOrig, err}
182 lockRelease := func() {
183 trace(CLock, "LOCK_UN: %s", fdLock.Name())
184 unix.Flock(int(fdLock.Fd()), unix.LOCK_UN)
187 trace(CLock, "LOCK_NB: %s", fdLock.Name())
189 // Waiting for job completion, already taken by someone else
190 if err = unix.Flock(int(fdLock.Fd()), unix.LOCK_EX|unix.LOCK_NB); err != nil {
191 if uintptr(err.(syscall.Errno)) != uintptr(unix.EWOULDBLOCK) {
193 return TgtErr{tgtOrig, err}
195 trace(CDebug, "waiting: %s", tgtOrig)
199 trace(CLock, "LOCK_EX: %s", fdLock.Name())
200 unix.Flock(int(fdLock.Fd()), unix.LOCK_EX)
202 trace(CDebug, "waiting done: %s", tgtOrig)
204 fdDep, err := os.Open(path.Join(redoDir, tgt+DepSuffix))
206 if os.IsNotExist(err) {
207 err = errors.New("was not built")
211 builtNow, _, err = isBuiltNow(fdDep)
216 err = errors.New("was not built")
220 err = TgtErr{tgtOrig, err}
227 // Check if target is not modified externally
228 modified, err := isModified(cwd, redoDir, tgt)
231 return TgtErr{tgtOrig, err}
234 trace(CWarn, "%s externally modified: not redoing", tgtOrig)
237 return TgtErr{tgtOrig, err}
240 // Start preparing .dep
241 fdDep, err := tempfile(redoDir, tgt+DepSuffix)
244 return TgtErr{tgtOrig, err}
249 os.Remove(fdDep.Name())
251 if _, err = recfile.NewWriter(fdDep).WriteFields(
252 recfile.Field{Name: "Build", Value: BuildUUID},
255 return TgtErr{tgtOrig, err}
259 doFile, upLevels, err := findDo(fdDep, cwd, tgt)
262 return TgtErr{tgtOrig, err}
266 return TgtErr{tgtOrig, errors.New("no .do found")}
268 if err = writeDep(fdDep, cwd, doFile); err != nil {
270 return TgtErr{tgtOrig, err}
273 // Determine basename and DIRPREFIX
274 ents := strings.Split(cwd, "/")
275 ents = ents[len(ents)-upLevels:]
276 dirPrefix := path.Join(ents...)
278 for i := 0; i < upLevels; i++ {
279 cwd = path.Join(cwd, "..")
281 cwd = path.Clean(cwd)
283 runErr := RunErr{Tgt: tgtOrig}
284 if strings.HasPrefix(doFile, "default.") {
285 basename = tgt[:len(tgt)-(len(doFile)-len("default.")-len(".do"))-1]
286 runErr.DoFile = doFile
288 trace(CWait, "%s", runErr.Name())
289 doFile = path.Base(doFile)
291 // Prepare command line
294 if err = unix.Access(path.Join(cwd, doFile), unix.X_OK); err == nil {
295 // Ordinary executable file
297 args = make([]string, 0, 3)
299 fd, err := os.Open(path.Join(cwd, doFile))
302 return TgtErr{tgtOrig, err}
304 buf := make([]byte, 512)
305 n, err := fd.Read(buf)
308 return TgtErr{tgtOrig, err}
310 if n > 3 && string(buf[:3]) == "#!/" {
312 t := string(buf[2:n])
313 nlIdx := strings.Index(t, "\n")
316 return TgtErr{tgtOrig, errors.New("not fully read shebang")}
318 args = strings.Split(t[:nlIdx], " ")
319 cmdName, args = args[0], args[1:]
324 args = append(args, "-ex")
326 args = append(args, "-e")
329 args = append(args, doFile)
332 // Temporary file for stdout
333 fdStdout, err := tempfile(cwd, tgt)
336 return TgtErr{tgtOrig, err}
338 tmpPath := fdStdout.Name() + ".3" // and for $3
339 args = append(args, tgt, basename, path.Base(tmpPath))
341 cmd := exec.Command(cmdName, args...)
343 cmd.Stdout = fdStdout
344 cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%d", EnvLevel, Level+1))
345 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvDirPrefix, dirPrefix))
346 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", EnvBuildUUID, BuildUUID))
347 childStderrPrefix := tempsuffix()
348 cmd.Env = append(cmd.Env, fmt.Sprintf(
349 "%s=%s", EnvStderrPrefix, childStderrPrefix,
352 cmd.ExtraFiles = append(cmd.ExtraFiles, fdDep)
354 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d", EnvDepFd, 3+fdNum))
358 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=NO", EnvJSFd))
360 cmd.ExtraFiles = append(cmd.ExtraFiles, JSR)
361 cmd.ExtraFiles = append(cmd.ExtraFiles, JSW)
362 cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%d,%d", EnvJSFd, 3+fdNum+0, 3+fdNum+1))
367 stderr, err := cmd.StderrPipe()
371 var fdStderr *os.File
373 fdStderr, err = os.OpenFile(
374 path.Join(redoDir, tgt+LogSuffix),
375 os.O_WRONLY|os.O_CREATE,
380 return TgtErr{tgtOrig, err}
384 shCtx := fmt.Sprintf("sh: %s: %s %s [%s]", tgtOrig, cmdName, args, cwd)
385 trace(CDebug, "%s", shCtx)
398 os.Remove(fdDep.Name())
399 os.Remove(fdStdout.Name())
401 os.Remove(fdLock.Name())
404 started := time.Now()
405 runErr.Started = &started
412 pid := fmt.Sprintf("[%d]", cmd.Process.Pid)
413 trace(CDebug, "%s runs %s", tgtOrig, pid)
415 stderrTerm := make(chan struct{}, 0)
417 scanner := bufio.NewScanner(stderr)
421 line = scanner.Text()
422 if strings.HasPrefix(line, childStderrPrefix) {
423 line = line[len(childStderrPrefix):]
424 os.Stderr.WriteString(StderrPrefix + line + "\n")
429 fmt.Fprintf(fdStderr, "@%s %s\n", hex.EncodeToString(ts[:]), line)
435 trace(CNone, "%s", line)
437 trace(CNone, "%s %s", pid, line)
443 // Wait for job completion
446 finished := time.Now()
447 runErr.Finished = &finished
454 // Does it produce both stdout and tmp?
455 fiStdout, err := os.Stat(fdStdout.Name())
462 _, err = os.Stat(tmpPath)
464 if fiStdout.Size() > 0 {
465 runErr.Err = errors.New("created both tmp and stdout")
470 } else if !os.IsNotExist(err) {
476 // Determine what file we must process at last
479 fd, err = os.Open(tmpPath)
484 } else if fiStdout.Size() > 0 {
488 // Do we need to ifcreate it, of ifchange with renaming?
490 err = ifcreate(fdDep, tgt)
501 err = os.Rename(fd.Name(), path.Join(cwdOrig, tgt))
506 err = syncDir(cwdOrig)
511 err = writeDep(fdDep, cwdOrig, tgt)
524 err = os.Rename(fdDep.Name(), path.Join(redoDir, tgt+DepSuffix))
529 err = syncDir(redoDir)