Golang FileInfo.WinsConflict方法代码示例

// ldbUpdateGlobal adds this device+version to the version list for the given
// file. If the device is already present in the list, the version is updated.
// If the file does not have an entry in the global list, it is created.
func ldbUpdateGlobal(db dbReader, batch dbWriter, folder, device []byte, file protocol.FileInfo) bool {
	if debugDB {
		l.Debugf("update global; folder=%q device=%v file=%q version=%d", folder, protocol.DeviceIDFromBytes(device), file.Name, file.Version)
	}
	name := []byte(file.Name)
	gk := globalKey(folder, name)
	svl, err := db.Get(gk, nil)
	if err != nil && err != leveldb.ErrNotFound {
		panic(err)
	}

	var fl versionList

	// Remove the device from the current version list
	if svl != nil {
		err = fl.UnmarshalXDR(svl)
		if err != nil {
			panic(err)
		}

		for i := range fl.versions {
			if bytes.Compare(fl.versions[i].device, device) == 0 {
				if fl.versions[i].version.Equal(file.Version) {
					// No need to do anything
					return false
				}
				fl.versions = append(fl.versions[:i], fl.versions[i+1:]...)
				break
			}
		}
	}

	nv := fileVersion{
		device:  device,
		version: file.Version,
	}

	// Find a position in the list to insert this file. The file at the front
	// of the list is the newer, the "global".
	for i := range fl.versions {
		switch fl.versions[i].version.Compare(file.Version) {
		case protocol.Equal, protocol.Lesser:
			// The version at this point in the list is equal to or lesser
			// ("older") than us. We insert ourselves in front of it.
			fl.versions = insertVersion(fl.versions, i, nv)
			goto done

		case protocol.ConcurrentLesser, protocol.ConcurrentGreater:
			// The version at this point is in conflict with us. We must pull
			// the actual file metadata to determine who wins. If we win, we
			// insert ourselves in front of the loser here. (The "Lesser" and
			// "Greater" in the condition above is just based on the device
			// IDs in the version vector, which is not the only thing we use
			// to determine the winner.)
			of, ok := ldbGet(db, folder, fl.versions[i].device, name)
			if !ok {
				panic("file referenced in version list does not exist")
			}
			if file.WinsConflict(of) {
				fl.versions = insertVersion(fl.versions, i, nv)
				goto done
			}
		}
	}

	// We didn't find a position for an insert above, so append to the end.
	fl.versions = append(fl.versions, nv)

done:
	if debugDB {
		l.Debugf("batch.Put %p %x", batch, gk)
		l.Debugf("new global after update: %v", fl)
	}
	batch.Put(gk, fl.MustMarshalXDR())

	return true
}

// updateGlobal adds this device+version to the version list for the given
// file. If the device is already present in the list, the version is updated.
// If the file does not have an entry in the global list, it is created.
func (t readWriteTransaction) updateGlobal(folder, device []byte, file protocol.FileInfo, globalSize *sizeTracker) bool {
	l.Debugf("update global; folder=%q device=%v file=%q version=%d", folder, protocol.DeviceIDFromBytes(device), file.Name, file.Version)
	name := []byte(file.Name)
	gk := globalKey(folder, name)
	svl, err := t.Get(gk, nil)
	if err != nil && err != leveldb.ErrNotFound {
		panic(err)
	}

	var fl versionList
	var oldFile protocol.FileInfo
	var hasOldFile bool
	// Remove the device from the current version list
	if svl != nil {
		err = fl.UnmarshalXDR(svl)
		if err != nil {
			panic(err)
		}

		for i := range fl.versions {
			if bytes.Compare(fl.versions[i].device, device) == 0 {
				if fl.versions[i].version.Equal(file.Version) {
					// No need to do anything
					return false
				}

				if i == 0 {
					// Keep the current newest file around so we can subtract it from
					// the globalSize if we replace it.
					oldFile, hasOldFile = t.getFile(folder, fl.versions[0].device, name)
				}

				fl.versions = append(fl.versions[:i], fl.versions[i+1:]...)
				break
			}
		}
	}

	nv := fileVersion{
		device:  device,
		version: file.Version,
	}

	insertedAt := -1
	// Find a position in the list to insert this file. The file at the front
	// of the list is the newer, the "global".
	for i := range fl.versions {
		switch fl.versions[i].version.Compare(file.Version) {
		case protocol.Equal, protocol.Lesser:
			// The version at this point in the list is equal to or lesser
			// ("older") than us. We insert ourselves in front of it.
			fl.versions = insertVersion(fl.versions, i, nv)
			insertedAt = i
			goto done

		case protocol.ConcurrentLesser, protocol.ConcurrentGreater:
			// The version at this point is in conflict with us. We must pull
			// the actual file metadata to determine who wins. If we win, we
			// insert ourselves in front of the loser here. (The "Lesser" and
			// "Greater" in the condition above is just based on the device
			// IDs in the version vector, which is not the only thing we use
			// to determine the winner.)
			of, ok := t.getFile(folder, fl.versions[i].device, name)
			if !ok {
				panic("file referenced in version list does not exist")
			}
			if file.WinsConflict(of) {
				fl.versions = insertVersion(fl.versions, i, nv)
				insertedAt = i
				goto done
			}
		}
	}

	// We didn't find a position for an insert above, so append to the end.
	fl.versions = append(fl.versions, nv)
	insertedAt = len(fl.versions) - 1

done:
	if insertedAt == 0 {
		// We just inserted a new newest version. Fixup the global size
		// calculation.
		if !file.Version.Equal(oldFile.Version) {
			globalSize.addFile(file)
			if hasOldFile {
				// We have the old file that was removed at the head of the list.
				globalSize.removeFile(oldFile)
			} else if len(fl.versions) > 1 {
				// The previous newest version is now at index 1, grab it from there.
				oldFile, ok := t.getFile(folder, fl.versions[1].device, name)
				if !ok {
					panic("file referenced in version list does not exist")
				}
				globalSize.removeFile(oldFile)
			}
		}
	}
//.........这里部分代码省略.........