2 goredo -- djb's redo implementation on pure Go
3 Copyright (C) 2020-2023 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/>.
18 // Out-of-date determination
32 "golang.org/x/sys/unix"
36 EnvOODTgtsFd = "REDO_OOD_TGTS_FD"
37 EnvOODTgtsLockFd = "REDO_OOD_TGTS_LOCK_FD"
41 OODTgts map[string]struct{}
43 FdOODTgtsLock *os.File
45 OODCache = make(map[string]bool)
46 FileExistsCache = make(map[string]bool)
49 func FileExists(p string) bool {
50 if exists, known := FileExistsCache[p]; known {
55 FileExistsCache[p] = true
58 if errors.Is(err, fs.ErrNotExist) {
59 FileExistsCache[p] = false
64 type TgtError struct {
69 func (e TgtError) Unwrap() error { return e.Err }
71 func (e TgtError) Error() string {
72 return fmt.Sprintf("%s: %s", e.Tgt, e.Err)
75 func isSrc(tgt *Tgt) bool {
76 if !FileExists(tgt.a) {
79 if FileExists(tgt.a + ".do") {
82 if FileExists(tgt.dep) {
88 func isOODByBuildUUID(tgt *Tgt) bool {
89 build, err := depBuildRead(tgt.dep)
90 return err != nil || build != BuildUUID
93 func isOOD(tgt *Tgt, level int, seen map[string]*Tgt) (bool, error) {
94 indent := strings.Repeat(". ", level)
95 tracef(CDebug, "ood: %s%s checking", indent, tgt)
96 ood, cached := OODCache[tgt.rel]
98 tracef(CDebug, "ood: %s%s -> cached: %v", indent, tgt, ood)
101 dep := DepCache[tgt.rel]
104 dep, err = depRead(tgt)
106 if errors.Is(err, fs.ErrNotExist) {
109 tracef(CDebug, "ood: %s%s -> is source", indent, tgt)
112 tracef(CDebug, "ood: %s%s -> no dep: %s", indent, tgt, tgt.dep)
114 OODCache[tgt.rel] = ood
118 return true, TgtError{tgt, ErrLine(err)}
121 DepCache[tgt.rel] = dep
124 if dep.build == BuildUUID {
125 tracef(CDebug, "ood: %s%s -> already built", indent, tgt)
126 OODCache[tgt.rel] = false
129 if !FileExists(tgt.a) {
130 tracef(CDebug, "ood: %s%s -> non-existent", indent, tgt)
131 OODCache[tgt.rel] = true
135 for _, ifcreate := range dep.ifcreates {
136 if FileExists(ifcreate.a) {
137 tracef(CDebug, "ood: %s%s -> %s created", indent, tgt, ifcreate)
143 for _, ifchange := range dep.ifchanges {
144 tracef(CDebug, "ood: %s%s -> %s: checking", indent, tgt, ifchange.tgt)
145 ood, cached = OODCache[ifchange.tgt.rel]
147 tracef(CDebug, "ood: %s%s -> %s: cached: %v", indent, tgt, ifchange.tgt, ood)
154 inode, err := inodeFromFileByPath(ifchange.tgt.a)
156 if errors.Is(err, fs.ErrNotExist) {
157 tracef(CDebug, "ood: %s%s -> %s: not exists", indent, tgt, ifchange.tgt)
159 OODCache[ifchange.tgt.rel] = ood
162 return ood, TgtError{tgt, ErrLine(err)}
165 if !bytes.Equal(inode[:8], ifchange.Inode()[:8]) {
166 tracef(CDebug, "ood: %s%s -> %s: size differs", indent, tgt, ifchange.tgt)
168 OODCache[ifchange.tgt.rel] = ood
171 if InodeTrust != InodeTrustNone && inode.Equals(ifchange.Inode()) {
172 tracef(CDebug, "ood: %s%s -> %s: same inode", indent, tgt, ifchange.tgt)
174 tracef(CDebug, "ood: %s%s -> %s: inode differs", indent, tgt, ifchange.tgt)
175 fd, err := os.Open(ifchange.tgt.a)
177 return ood, TgtError{tgt, ErrLine(err)}
179 hsh, err := fileHash(fd)
182 return ood, TgtError{tgt, ErrLine(err)}
184 if ifchange.Hash() != hsh {
185 tracef(CDebug, "ood: %s%s -> %s: hash differs", indent, tgt, ifchange.tgt)
187 OODCache[ifchange.tgt.rel] = ood
190 tracef(CDebug, "ood: %s%s -> %s: same hash", indent, tgt, ifchange.tgt)
193 if ifchange.tgt.rel == tgt.rel {
194 tracef(CDebug, "ood: %s%s -> %s: same target", indent, tgt, ifchange.tgt)
197 if isSrc(ifchange.tgt) {
198 tracef(CDebug, "ood: %s%s -> %s: is source", indent, tgt, ifchange.tgt)
199 OODCache[ifchange.tgt.rel] = false
203 if _, ok := seen[ifchange.tgt.rel]; ok {
204 tracef(CDebug, "ood: %s%s -> %s: was always built", indent, tgt, ifchange.tgt)
205 OODCache[ifchange.tgt.rel] = false
209 depOOD, err := isOODWithTrace(ifchange.tgt, level+1, seen)
211 return ood, TgtError{tgt, err}
214 tracef(CDebug, "ood: %s%s -> %s: ood", indent, tgt, ifchange.tgt)
218 tracef(CDebug, "ood: %s%s -> %s: !ood", indent, tgt, ifchange.tgt)
222 tracef(CDebug, "ood: %s%s: %v", indent, tgt, ood)
223 OODCache[tgt.rel] = ood
227 func isOODWithTrace(tgt *Tgt, level int, seen map[string]*Tgt) (bool, error) {
228 _, ood := OODTgts[tgt.a]
231 if !isOODByBuildUUID(tgt) {
232 tracef(CDebug, "ood: %s%s -> already built", strings.Repeat(". ", level), tgt)
235 tracef(CDebug, "ood: %s%s true, external decision", strings.Repeat(". ", level), tgt)
238 ood, err = isOOD(tgt, level, seen)
243 flock := unix.Flock_t{
245 Whence: io.SeekStart,
247 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLKW, &flock); err != nil {
250 if _, err = FdOODTgts.Seek(0, io.SeekEnd); err != nil {
253 if _, err := FdOODTgts.WriteString(tgt.a + "\x00"); err != nil {
256 flock.Type = unix.F_UNLCK
257 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLK, &flock); err != nil {
263 func oodTgtsClear() {
265 flock := unix.Flock_t{
267 Whence: io.SeekStart,
269 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLKW, &flock); err != nil {
272 if err = FdOODTgts.Truncate(0); err != nil {
275 flock.Type = unix.F_UNLCK
276 if err = unix.FcntlFlock(FdOODTgtsLock.Fd(), unix.F_SETLK, &flock); err != nil {