Stop folder when running out of disk space (fixes #2057)

& tweaks by calmh

lib/model/model.go

@@ -45,6 +45,7 @@ const (
 	indexBatchSize         = 1000       // Either way, don't include more files than this
 	reqValidationTime      = time.Hour  // How long to cache validation entries for Request messages
 	reqValidationCacheSize = 1000       // How many entries to aim for in the validation cache size
+	minHomeDiskFreePct     = 1.0        // Stop when less space than this is available on the home (config & db) disk
 )
 
 type service interface {
@@ -1230,6 +1231,10 @@ func (m *Model) internalScanFolderSubs(folder string, subs []string) error {
 		return errors.New("no such folder")
 	}
 
+	if err := m.CheckFolderHealth(folder); err != nil {
+		return err
+	}
+
 	_ = ignores.Load(filepath.Join(folderCfg.Path(), ".stignore")) // Ignore error, there might not be an .stignore
 
 	// Required to make sure that we start indexing at a directory we're already
@@ -1658,6 +1663,10 @@ func (m *Model) BringToFront(folder, file string) {
 // CheckFolderHealth checks the folder for common errors and returns the
 // current folder error, or nil if the folder is healthy.
 func (m *Model) CheckFolderHealth(id string) error {
+	if free, err := osutil.DiskFreePercentage(m.cfg.ConfigPath()); err == nil && free < minHomeDiskFreePct {
+		return errors.New("out of disk space")
+	}
+
 	folder, ok := m.cfg.Folders()[id]
 	if !ok {
 		return errors.New("folder does not exist")
@@ -1673,6 +1682,8 @@ func (m *Model) CheckFolderHealth(id string) error {
 			err = errors.New("folder path missing")
 		} else if !folder.HasMarker() {
 			err = errors.New("folder marker missing")
+		} else if free, errDfp := osutil.DiskFreePercentage(folder.Path()); errDfp == nil && free < float64(folder.MinDiskFreePct) {
+			err = errors.New("out of disk space")
 		}
 	} else if os.IsNotExist(err) {
 		// If we don't have any files in the index, and the directory

lib/model/rwfolder.go

@@ -437,6 +437,7 @@ func (p *rwFolder) pullerIteration(ignores *ignore.Matcher) int {
 	// !!!
 
 	changed := 0
+	pullFileSize := int64(0)
 
 	fileDeletions := map[string]protocol.FileInfo{}
 	dirDeletions := []protocol.FileInfo{}
@@ -485,6 +486,7 @@ func (p *rwFolder) pullerIteration(ignores *ignore.Matcher) int {
 		default:
 			// A new or changed file or symlink. This is the only case where we
 			// do stuff concurrently in the background
+			pullFileSize += file.Size()
 			p.queue.Push(file.Name, file.Size(), file.Modified)
 		}
 
@@ -492,6 +494,17 @@ func (p *rwFolder) pullerIteration(ignores *ignore.Matcher) int {
 		return true
 	})
 
+	// Check if we are able to store all files on disk
+	if pullFileSize > 0 {
+		folder, ok := p.model.cfg.Folders()[p.folder]
+		if ok {
+			if free, err := osutil.DiskFreeBytes(folder.Path()); err == nil && free < pullFileSize {
+				l.Infof("Puller (folder %q): insufficient disk space available to pull %d files (%.2fMB)", p.folder, changed, float64(pullFileSize)/1024/1024)
+				return 0
+			}
+		}
+	}
+
 	// Reorder the file queue according to configuration
 
 	switch p.order {