From ecf9d95f07ebf9f655b363452cf2123c1a53aee0 Mon Sep 17 00:00:00 2001 From: luk3yx Date: Fri, 27 May 2022 14:36:20 +1200 Subject: Initial commit --- LICENSE.md | 660 +++++++++++++++++++++++++++++++++++++++++++++++++++++ README.md | 35 +++ decsync-vdir.go | 687 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1382 insertions(+) create mode 100644 LICENSE.md create mode 100644 README.md create mode 100755 decsync-vdir.go diff --git a/LICENSE.md b/LICENSE.md new file mode 100644 index 0000000..cba6f6a --- /dev/null +++ b/LICENSE.md @@ -0,0 +1,660 @@ +### GNU AFFERO GENERAL PUBLIC LICENSE + +Version 3, 19 November 2007 + +Copyright (C) 2007 Free Software Foundation, Inc. + + +Everyone is permitted to copy and distribute verbatim copies of this +license document, but changing it is not allowed. + +### Preamble + +The GNU Affero General Public License is a free, copyleft license for +software and other kinds of works, specifically designed to ensure +cooperation with the community in the case of network server software. + +The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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Additional Terms. + +"Additional permissions" are terms that supplement the terms of this +License by making exceptions from one or more of its conditions. +Additional permissions that are applicable to the entire Program shall +be treated as though they were included in this License, to the extent +that they are valid under applicable law. If additional permissions +apply only to part of the Program, that part may be used separately +under those permissions, but the entire Program remains governed by +this License without regard to the additional permissions. + +When you convey a copy of a covered work, you may at your option +remove any additional permissions from that copy, or from any part of +it. (Additional permissions may be written to require their own +removal in certain cases when you modify the work.) 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If the Program as you +received it, or any part of it, contains a notice stating that it is +governed by this License along with a term that is a further +restriction, you may remove that term. If a license document contains +a further restriction but permits relicensing or conveying under this +License, you may add to a covered work material governed by the terms +of that license document, provided that the further restriction does +not survive such relicensing or conveying. + +If you add terms to a covered work in accord with this section, you +must place, in the relevant source files, a statement of the +additional terms that apply to those files, or a notice indicating +where to find the applicable terms. + +Additional terms, permissive or non-permissive, may be stated in the +form of a separately written license, or stated as exceptions; the +above requirements apply either way. + +#### 8. Termination. + +You may not propagate or modify a covered work except as expressly +provided under this License. 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If your rights have been terminated and not permanently +reinstated, you do not qualify to receive new licenses for the same +material under section 10. + +#### 9. Acceptance Not Required for Having Copies. + +You are not required to accept this License in order to receive or run +a copy of the Program. Ancillary propagation of a covered work +occurring solely as a consequence of using peer-to-peer transmission +to receive a copy likewise does not require acceptance. However, +nothing other than this License grants you permission to propagate or +modify any covered work. These actions infringe copyright if you do +not accept this License. Therefore, by modifying or propagating a +covered work, you indicate your acceptance of this License to do so. + +#### 10. Automatic Licensing of Downstream Recipients. + +Each time you convey a covered work, the recipient automatically +receives a license from the original licensors, to run, modify and +propagate that work, subject to this License. You are not responsible +for enforcing compliance by third parties with this License. + +An "entity transaction" is a transaction transferring control of an +organization, or substantially all assets of one, or subdividing an +organization, or merging organizations. If propagation of a covered +work results from an entity transaction, each party to that +transaction who receives a copy of the work also receives whatever +licenses to the work the party's predecessor in interest had or could +give under the previous paragraph, plus a right to possession of the +Corresponding Source of the work from the predecessor in interest, if +the predecessor has it or can get it with reasonable efforts. + +You may not impose any further restrictions on the exercise of the +rights granted or affirmed under this License. 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"Knowingly relying" means you have +actual knowledge that, but for the patent license, your conveying the +covered work in a country, or your recipient's use of the covered work +in a country, would infringe one or more identifiable patents in that +country that you have reason to believe are valid. + +If, pursuant to or in connection with a single transaction or +arrangement, you convey, or propagate by procuring conveyance of, a +covered work, and grant a patent license to some of the parties +receiving the covered work authorizing them to use, propagate, modify +or convey a specific copy of the covered work, then the patent license +you grant is automatically extended to all recipients of the covered +work and works based on it. + +A patent license is "discriminatory" if it does not include within the +scope of its coverage, prohibits the exercise of, or is conditioned on +the non-exercise of one or more of the rights that are specifically +granted under this License. You may not convey a covered work if you +are a party to an arrangement with a third party that is in the +business of distributing software, under which you make payment to the +third party based on the extent of your activity of conveying the +work, and under which the third party grants, to any of the parties +who would receive the covered work from you, a discriminatory patent +license (a) in connection with copies of the covered work conveyed by +you (or copies made from those copies), or (b) primarily for and in +connection with specific products or compilations that contain the +covered work, unless you entered into that arrangement, or that patent +license was granted, prior to 28 March 2007. + +Nothing in this License shall be construed as excluding or limiting +any implied license or other defenses to infringement that may +otherwise be available to you under applicable patent law. + +#### 12. No Surrender of Others' Freedom. + +If conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot convey a +covered work so as to satisfy simultaneously your obligations under +this License and any other pertinent obligations, then as a +consequence you may not convey it at all. For example, if you agree to +terms that obligate you to collect a royalty for further conveying +from those to whom you convey the Program, the only way you could +satisfy both those terms and this License would be to refrain entirely +from conveying the Program. + +#### 13. Remote Network Interaction; Use with the GNU General Public License. + +Notwithstanding any other provision of this License, if you modify the +Program, your modified version must prominently offer all users +interacting with it remotely through a computer network (if your +version supports such interaction) an opportunity to receive the +Corresponding Source of your version by providing access to the +Corresponding Source from a network server at no charge, through some +standard or customary means of facilitating copying of software. This +Corresponding Source shall include the Corresponding Source for any +work covered by version 3 of the GNU General Public License that is +incorporated pursuant to the following paragraph. + +Notwithstanding any other provision of this License, you have +permission to link or combine any covered work with a work licensed +under version 3 of the GNU General Public License into a single +combined work, and to convey the resulting work. The terms of this +License will continue to apply to the part which is the covered work, +but the work with which it is combined will remain governed by version +3 of the GNU General Public License. + +#### 14. Revised Versions of this License. + +The Free Software Foundation may publish revised and/or new versions +of the GNU Affero General Public License from time to time. Such new +versions will be similar in spirit to the present version, but may +differ in detail to address new problems or concerns. + +Each version is given a distinguishing version number. If the Program +specifies that a certain numbered version of the GNU Affero General +Public License "or any later version" applies to it, you have the +option of following the terms and conditions either of that numbered +version or of any later version published by the Free Software +Foundation. If the Program does not specify a version number of the +GNU Affero General Public License, you may choose any version ever +published by the Free Software Foundation. + +If the Program specifies that a proxy can decide which future versions +of the GNU Affero General Public License can be used, that proxy's +public statement of acceptance of a version permanently authorizes you +to choose that version for the Program. + +Later license versions may give you additional or different +permissions. However, no additional obligations are imposed on any +author or copyright holder as a result of your choosing to follow a +later version. + +#### 15. Disclaimer of Warranty. + +THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY +APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT +HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT +WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND +PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE +DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR +CORRECTION. + +#### 16. Limitation of Liability. + +IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR +CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES +ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT +NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR +LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM +TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER +PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. + +#### 17. Interpretation of Sections 15 and 16. + +If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. + +END OF TERMS AND CONDITIONS + +### How to Apply These Terms to Your New Programs + +If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these +terms. + +To do so, attach the following notices to the program. It is safest to +attach them to the start of each source file to most effectively state +the exclusion of warranty; and each file should have at least the +"copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero General Public License as + published by the Free Software Foundation, either version 3 of the + License, or (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper +mail. + +If your software can interact with users remotely through a computer +network, you should also make sure that it provides a way for users to +get its source. For example, if your program is a web application, its +interface could display a "Source" link that leads users to an archive +of the code. There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for +the specific requirements. + +You should also get your employer (if you work as a programmer) or +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. For more information on this, and how to apply and follow +the GNU AGPL, see . diff --git a/README.md b/README.md new file mode 100644 index 0000000..a8047b7 --- /dev/null +++ b/README.md @@ -0,0 +1,35 @@ +# decsync-vdir + +Synchronises [DecSync](https://github.com/39aldo39/DecSync) contacts/calendars +with a [vdir](https://vdirsyncer.pimutils.org/en/stable/vdir.html). + +## Usage + +Make sure you have Go 1.16 or later installed. + +Building decsync-vdir: + +``` +$ go build decsync-vdir.go +``` + +Syncing a contacts directory with DecSync: + +``` +$ ./decsync-vdir /path/to/decsync/contacts/ /path/to/vdir .vcf +``` + +Syncing a calendar directory with DecSync: + +``` +$ ./decsync-vdir /path/to/decsync/calendars/ /path/to/vdir .ics +``` + +The vdir directory will be created if it doesn't already exist. + +## Limitations + + - Deleting a file in the vdir will not delete it on DecSync, `decsync-vdir` + will recreate the file inside the vdir instead. + - `decsync-vdir` doesn't store entries created on other devices in its own + storage directory under `v2`. diff --git a/decsync-vdir.go b/decsync-vdir.go new file mode 100755 index 0000000..99dd792 --- /dev/null +++ b/decsync-vdir.go @@ -0,0 +1,687 @@ +// +// decsync-vdir +// Copyright © 2022 by luk3yx +// +// This program is free software: you can redistribute it and/or modify +// it under the terms of the GNU Affero General Public License as +// published by the Free Software Foundation, either version 3 of the +// License, or (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Affero General Public License for more details. +// +// You should have received a copy of the GNU Affero General Public License +// along with this program. If not, see . +// + +package main + +import ( + "bufio" + "bytes" + cryptoRand "crypto/rand" + "encoding/json" + "errors" + "fmt" + "io" + "os" + "regexp" + "strings" + "time" +) + +type any = interface{} + +var infoPath = []string{"info"} +var ErrNoDeviceName = errors.New("No device name specified (read-only mode)") +var safeFilenameRegex = regexp.MustCompile(`^[A-Za-z0-9\-_]+$`) + +func isUnsafeFilename(fn string) bool { + return safeFilenameRegex.Find([]byte(fn)) == nil +} + +func assert(err error) { + if err != nil { + panic(err) + } +} + +func uuid4() string { + var uuid [16]byte + _, err := cryptoRand.Read(uuid[:]) + assert(err) + uuid[6] = (uuid[6] & 0x0f) | 0x40 + uuid[8] = (uuid[8] & 0x3f) | 0x80 + s := fmt.Sprintf("%032x", uuid) + return fmt.Sprintf("%s-%s-%s-%s-%s", s[:8], s[8:12], s[12:16], s[16:20], s[20:]) +} + +// This code doesn't work exactly like libdecsync, it doesn't bother updating +// its own entry files with any new entries. +func getPathHash(path []string) string { + if len(path) == 1 && path[0] == "info" { + return "info" + } + var hash uint8 + for _, component := range path { + var componentHash uint8 + for _, b := range []byte(component) { + componentHash = componentHash*19 + b + } + hash = hash*199 + componentHash + } + return fmt.Sprintf("%02x", hash) +} + +func pathEquals(p1, p2 []string) bool { + if len(p1) != len(p2) { + return false + } + + for i, v1 := range p1 { + if v1 != p2[i] { + return false + } + } + return true +} + +func pathStartsWith(p1, p2 []string) bool { + if len(p1) < len(p2) { + return false + } + + for i, v2 := range p2 { + if v2 != p1[i] { + return false + } + } + return true +} + +func isDir(path string) (bool, error) { + info, err := os.Stat(path) + if errors.Is(err, os.ErrNotExist) { + return false, nil + } else if err != nil { + return false, err + } + return info.IsDir(), nil +} + +type DecSyncFolder struct { + directory string + deviceName string + lastActiveDay time.Time +} + +type SyncEntry struct { + deviceName string + Path []string + LastModified time.Time + Key any + Value any +} + +const decsyncTimeFormat = "2006-01-02T15:04:05" + +func (e *SyncEntry) UnmarshalJSON(data []byte) error { + var dateStr string + var arr = [4]any{&e.Path, &dateStr, &e.Key, &e.Value} + err := json.Unmarshal(data, &arr) + if err == nil { + e.LastModified, err = time.Parse(decsyncTimeFormat, dateStr) + } + return err +} + +func (e SyncEntry) MarshalJSON() ([]byte, error) { + dateStr := e.LastModified.UTC().Format(decsyncTimeFormat) + return json.Marshal([4]any{e.Path, dateStr, e.Key, e.Value}) +} + +func (d *DecSyncFolder) Exists() (bool, error) { + return isDir(d.directory + "/v2") +} + +func (d *DecSyncFolder) readAllEntries(path []string, callback func(SyncEntry)) error { + deviceDirs, err := os.ReadDir(d.directory + "/v2") + if err != nil { + return err + } + + hash := getPathHash(path) + for _, dir := range deviceDirs { + err = d.parseFile(dir.Name(), hash, callback) + if err != nil && !errors.Is(err, os.ErrNotExist) { + return err + } + } + + return nil +} + +func (d *DecSyncFolder) parseFile(deviceName, hash string, callback func(SyncEntry)) error { + f, err := os.Open(d.directory + "/v2/" + deviceName + "/" + hash) + if err != nil { + return err + } + defer f.Close() + + scanner := bufio.NewScanner(f) + for scanner.Scan() { + var entry SyncEntry + if err = json.Unmarshal(scanner.Bytes(), &entry); err != nil { + return err + } + entry.deviceName = deviceName + callback(entry) + } + return nil +} + +func insertEntryIfNewer(entries map[any]SyncEntry, entry SyncEntry) { + curEntry := entries[entry.Key] + if entry.LastModified.After(curEntry.LastModified) { + entries[entry.Key] = entry + } +} + +// Iterates over everything starting with the path prefix +func (d *DecSyncFolder) Iter(pathPrefix []string, includeDeleted bool, callback func(SyncEntry) error) error { + deviceDirs, err := os.ReadDir(d.directory + "/v2") + if err != nil { + return err + } + + // Collect all the filenames that need to be searched + hashes := make(map[string][]string) + for _, dir := range deviceDirs { + data, err := os.ReadFile(d.directory + "/v2/" + dir.Name() + "/sequences") + if err != nil { + return err + } + var sequences map[string]uint64 + if err = json.Unmarshal(data, &sequences); err != nil { + return err + } + + // Add every hash to the hashes list + for hash := range sequences { + hashes[hash] = append(hashes[hash], dir.Name()) + } + } + + // Now read all entries one file at a time + for hash, devicesWithHash := range hashes { + // Create an entries map from all devices that have the file + entries := make(map[any]SyncEntry) + for _, deviceName := range devicesWithHash { + err = d.parseFile(deviceName, hash, func(entry SyncEntry) { + if pathStartsWith(entry.Path, pathPrefix) { + insertEntryIfNewer(entries, entry) + } + }) + if err != nil { + return err + } + } + + // Run the callbacks on this "batch" of entries + for _, entry := range entries { + // Don't process deleted entries + if !includeDeleted && entry.Value == nil { + continue + } + + if err = callback(entry); err != nil { + return err + } + } + } + + return nil +} + +// Gets all values in a path +func (d *DecSyncFolder) GetAll(path []string) (map[any]any, error) { + entries := make(map[any]SyncEntry) + err := d.readAllEntries(path, func(entry SyncEntry) { + if pathEquals(entry.Path, path) { + insertEntryIfNewer(entries, entry) + } + }) + if err != nil { + return nil, err + } + + values := make(map[any]any, len(entries)) + for k, entry := range entries { + if entry.Value != nil { + values[k] = entry.Value + } + } + return values, nil +} + +// Gets one value from a path +func (d *DecSyncFolder) Get(path []string, key any) (any, error) { + var curEntry SyncEntry + err := d.readAllEntries(path, func(entry SyncEntry) { + if pathEquals(entry.Path, path) && key == entry.Key && entry.LastModified.After(curEntry.LastModified) { + curEntry = entry + } + }) + return curEntry.Value, err +} + +// Gets the name (or an empty string on error) +func (d *DecSyncFolder) Name() string { + name, err := d.Get(infoPath, "name") + if err != nil { + return "" + } + nameStr, _ := name.(string) + return nameStr +} + +func writeIfNotExist(dir, fn string, content []byte) error { + if err := os.MkdirAll(dir, 0750); err != nil { + return err + } + f, err := os.OpenFile(dir+"/"+fn, os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0640) + if err != nil { + if errors.Is(err, os.ErrExist) { + return nil + } + return err + } + defer f.Close() + _, err = f.Write(content) + return err +} + +func (d *DecSyncFolder) writeDeviceInfo() error { + if d.deviceName == "" { + return ErrNoDeviceName + } + + // Create the "local" directory + localDeviceDir := d.directory + "/local/" + d.deviceName + if err := os.MkdirAll(localDeviceDir, 0750); err != nil { + return err + } + + // If the last-active value was already updated today then don't bother + // updating it again + utcNow := time.Now().UTC() + utcToday := utcNow.Truncate(24 * time.Hour) + if d.lastActiveDay.Equal(utcToday) { + return nil + } + + // Write to the "info" file + lastActiveStr := utcToday.Format("2006-01-02") + data, err := json.Marshal(map[string]any{ + "version": 2, + "last-active": lastActiveStr, + "supported-version": 2, + }) + assert(err) + + data = append(data, '\n') + if err = os.WriteFile(localDeviceDir+"/info", data, 0640); err != nil { + return err + } + + // Make sure our /v2/ directory exists + if err = os.MkdirAll(d.directory+"/v2/"+d.deviceName, 0750); err != nil { + return err + } + + // Update the "last active" and "supported version" entries + err = d.insertEntryRaw(SyncEntry{ + Path: infoPath, + LastModified: utcNow, + Key: "last-active-" + d.deviceName, + Value: lastActiveStr, + }) + if err == nil { + err = d.insertEntryRaw(SyncEntry{ + Path: infoPath, + LastModified: utcNow, + Key: "supported-version-" + d.deviceName, + Value: 2, + }) + + if err == nil { + d.lastActiveDay = utcToday + } + } + return err +} + +func atomicWriteFile(fn string, data []byte) error { + tmpFn := fn + ".tmp" + if err := os.WriteFile(tmpFn, data, 0640); err != nil { + return err + } + return os.Rename(tmpFn, fn) +} + +// Sets a value +func (d *DecSyncFolder) Set(path []string, key, value any) error { + return d.InsertEntry(SyncEntry{ + Path: path, + LastModified: time.Now(), + Key: key, + Value: value, + }) +} + +func (d *DecSyncFolder) InsertEntry(newEntry SyncEntry) error { + if err := d.writeDeviceInfo(); err != nil { + return err + } + return d.insertEntryRaw(newEntry) +} + +func (d *DecSyncFolder) insertEntryRaw(newEntry SyncEntry) error { + // Read existing entries + entries := make([]SyncEntry, 0, 1) + hash := getPathHash(newEntry.Path) + err := d.parseFile(d.deviceName, hash, func(entry SyncEntry) { + if !pathEquals(newEntry.Path, entry.Path) || newEntry.Key != entry.Key { + entries = append(entries, entry) + } + }) + if err != nil && !errors.Is(err, os.ErrNotExist) { + return err + } + + // Read the sequences file + v2Dir := d.directory + "/v2/" + d.deviceName + "/" + sequencesFn := v2Dir + "sequences" + data, err := os.ReadFile(sequencesFn) + if err != nil { + if !errors.Is(err, os.ErrNotExist) { + return err + } + data = []byte("{}") + } + + // Increment the modified hash + var sequences map[string]uint64 + if err = json.Unmarshal(data, &sequences); err != nil { + return err + } + sequences[hash]++ + + // Write the sequences file back + // This is done before writing the hash file because it's probably safe to + // increment the sequences number without changing anything + data, err = json.Marshal(sequences) + assert(err) + if err = atomicWriteFile(sequencesFn, append(data, '\n')); err != nil { + return err + } + + // Add new entry + entries = append(entries, newEntry) + + // Write all the entries back as JSON + var b bytes.Buffer + for _, entry := range entries { + data, err := json.Marshal(entry) + if err != nil { + return err + } + b.Write(data) + b.WriteByte('\n') + } + + return atomicWriteFile(v2Dir+hash, b.Bytes()) +} + +// For handling contacts/calendars +func (d *DecSyncFolder) GetResource(uid string) (string, error) { + resource, err := d.Get([]string{"resources", uid}, nil) + if err != nil || resource == nil { + return "", err + } else if resourceStr, ok := resource.(string); ok { + return resourceStr, nil + } + return "", errors.New("Invalid resource type") +} + +func (d *DecSyncFolder) UpdateResource(uid string, newData string, ts time.Time) error { + return d.InsertEntry(SyncEntry{ + Path: []string{"resources", uid}, + LastModified: ts, + Key: nil, + Value: newData, + }) +} + +func (d *DecSyncFolder) DeleteResource(uid string) error { + return d.Set([]string{"resources", uid}, nil, nil) +} + +func (d *DecSyncFolder) CreateResource(data string, ts time.Time) (string, error) { + uid := uuid4() + return uid, d.UpdateResource(uid, data, ts) +} + +func (d *DecSyncFolder) IterResources(includeDeleted bool, callback func(string, string, time.Time) error) error { + return d.Iter([]string{"resources"}, includeDeleted, func(entry SyncEntry) error { + if entry.Key != nil { + return nil + } + data, ok := entry.Value.(string) + if !ok && entry.Value != nil { + return errors.New("Invalid resource type") + } + return callback(entry.Path[1], data, entry.LastModified) + }) +} + +func getVcardUID(reader io.Reader) (string, error) { + scanner := bufio.NewScanner(reader) + for scanner.Scan() { + if bytes.HasPrefix(scanner.Bytes(), []byte("UID:")) { + return string(scanner.Bytes()[4:]), nil + } + } + return "", scanner.Err() +} + +type uidToPathMap struct { + m map[string]string + local map[string]struct{} + vdir string + fileExtension string +} + +func (m uidToPathMap) addFile(vdirFile string) error { + f, err := os.Open(vdirFile) + if err != nil { + return err + } + defer f.Close() + uid, err := getVcardUID(f) + if err == nil { + if uid == "" { + return errors.New("Could not read UID from " + vdirFile) + } else if otherFile, exists := m.m[uid]; exists { + return fmt.Errorf("Files %q and %q have the same UID", vdirFile, otherFile) + } + m.m[uid] = vdirFile + m.local[uid] = struct{}{} + } + return err +} + +func (m uidToPathMap) getPath(uid string) string { + if path, ok := m.m[uid]; ok { + return path + } else if isUnsafeFilename(uid) { + uid = uuid4() + } + return m.vdir + uid + m.fileExtension +} + +func SyncVdir(sync *DecSyncFolder, vdir, fileExtension string) error { + if !strings.HasSuffix(vdir, "/") { + vdir += "/" + } + if fileExtension != "" && (fileExtension[0] != '.' || isUnsafeFilename(fileExtension[1:])) { + return fmt.Errorf("Invalid file extension: %q", fileExtension) + } + + if err := os.MkdirAll(vdir, 0750); err != nil { + return err + } + + m := uidToPathMap{ + m: make(map[string]string), + local: make(map[string]struct{}), + vdir: vdir, + fileExtension: fileExtension, + } + files, err := os.ReadDir(vdir) + if err != nil { + return err + } + for _, file := range files { + if !strings.HasSuffix(file.Name(), fileExtension) { + continue + } + if err = m.addFile(vdir + file.Name()); err != nil { + return err + } + } + + // Sync contacts that exist on DecSync + err = sync.IterResources(true, func(uid, syncData string, syncModified time.Time) error { + if isUnsafeFilename(uid) { + return errors.New("UUID is not a safe filename") + } + + // The file was "seen" by DecSync so it isn't local + delete(m.local, uid) + + vdirFile := m.getPath(uid) + info, err := os.Stat(vdirFile) + var vdirModified time.Time + if err == nil { + vdirModified = info.ModTime().Truncate(time.Second) + } else if !errors.Is(err, os.ErrNotExist) { + return err + } else if syncData == "" { + // fmt.Println("Deleted on both sides: " + vdirFile) + return nil + } + + if syncModified.Before(vdirModified) { + // vdir → DecSync + fmt.Println("Updating DecSync: "+vdirFile, syncModified, vdirModified) + content, err := os.ReadFile(vdirFile) + if err != nil { + return err + } + return sync.UpdateResource(uid, string(content), vdirModified) + } else if vdirModified.Before(syncModified) { + // DecSync → vdir + // fmt.Println("Updating vdir: "+vdirFile, syncModified, vdirModified) + if syncData == "" { + return os.Remove(vdirFile) + } + err = atomicWriteFile(vdirFile, []byte(syncData)) + if err == nil { + err = os.Chtimes(vdirFile, time.Now(), syncModified) + } + return err + } else { + // fmt.Println("Not modified: " + vdirFile) + return nil + } + }) + + for uid := range m.local { + vdirFile, ok := m.m[uid] + if !ok { + panic("Unreachable code") + } + + fmt.Println("Creating on DecSync: " + vdirFile) + info, err := os.Stat(vdirFile) + if err != nil { + return err + } + vdirModified := info.ModTime().Truncate(time.Second) + content, err := os.ReadFile(vdirFile) + if err != nil { + return err + } + + if err = sync.UpdateResource(uid, string(content), vdirModified); err != nil { + return err + } + } + return nil +} + +func main() { + if len(os.Args) != 4 { + fmt.Fprintln(os.Stderr, "Usage: decsync-vdir /path/to/decsync/contacts/uuid /path/to/vdir .vcf") + os.Exit(1) + } + + deviceName, err := os.Hostname() + assert(err) + if isUnsafeFilename(deviceName) { + fmt.Fprintf(os.Stderr, "Warning: This system's hostname (%q) cannot "+ + "be used as a filename, read-only mode enabled.\n", deviceName) + deviceName = "" + } + + sync := DecSyncFolder{ + directory: os.Args[1], + deviceName: deviceName, + } + + syncExists, err := sync.Exists() + assert(err) + if !syncExists { + fmt.Fprintln(os.Stderr, "Error: The specified DecSync directory doesn't look valid!") + + // Try to print a more helpful error message + possiblyRootDecsyncDir, err := isDir(sync.directory + "/contacts") + assert(err) + if !possiblyRootDecsyncDir { + possiblyRootDecsyncDir, err = isDir(sync.directory + "/calendars") + assert(err) + } + + if possiblyRootDecsyncDir { + fmt.Fprintf(os.Stderr, "Try using %[1]s/contacts/ or "+ + "%[1]s/calendars/ instead.\n", sync.directory) + fmt.Fprintf(os.Stderr, " can be found with "+ + "`ls %q/{contacts,calendars}`\n", sync.directory) + } else { + fmt.Fprintf(os.Stderr, "If know what you're doing, you can run "+ + "`mkdir %q` to ignore this error.\n", sync.directory+"/v2") + } + os.Exit(1) + } + + // fmt.Println("Syncing...") + err = SyncVdir(&sync, os.Args[2], os.Args[3]) + if err != nil { + fmt.Fprintf(os.Stderr, "Error: %s\n", err.Error()) + os.Exit(1) + } + // fmt.Println("Synced!") +} -- cgit v1.2.3