X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/8296c0784c70660e0a7247ba000741d37bda38fd..8bf8c9c62a53012de2847c07b38460d57824c559:/sdk/go/arvados/fs_base.go

diff --git a/sdk/go/arvados/fs_base.go b/sdk/go/arvados/fs_base.go
index 369b4bb942..d06aba3695 100644
--- a/sdk/go/arvados/fs_base.go
+++ b/sdk/go/arvados/fs_base.go
@@ -58,6 +58,9 @@ type FileSystem interface {
 	// while locking multiple inodes.
 	locker() sync.Locker
 
+	// throttle for limiting concurrent background writers
+	throttle() *throttle
+
 	// create a new node with nil parent.
 	newNode(name string, perm os.FileMode, modTime time.Time) (node inode, err error)
 
@@ -86,7 +89,19 @@ type FileSystem interface {
 	Remove(name string) error
 	RemoveAll(name string) error
 	Rename(oldname, newname string) error
+
+	// Write buffered data from memory to storage, returning when
+	// all updates have been saved to persistent storage.
 	Sync() error
+
+	// Write buffered data from memory to storage, but don't wait
+	// for all writes to finish before returning. If shortBlocks
+	// is true, flush everything; otherwise, if there's less than
+	// a full block of buffered data at the end of a stream, leave
+	// it buffered in memory in case more data can be appended. If
+	// path is "", flush all dirs/streams; otherwise, flush only
+	// the specified dir/stream.
+	Flush(path string, shortBlocks bool) error
 }
 
 type inode interface {
@@ -103,6 +118,9 @@ type inode interface {
 
 	// Child() performs lookups and updates of named child nodes.
 	//
+	// (The term "child" here is used strictly. This means name is
+	// not "." or "..", and name does not contain "/".)
+	//
 	// If replace is non-nil, Child calls replace(x) where x is
 	// the current child inode with the given name. If possible,
 	// the child inode is replaced with the one returned by
@@ -285,12 +303,17 @@ type fileSystem struct {
 	root inode
 	fsBackend
 	mutex sync.Mutex
+	thr   *throttle
 }
 
 func (fs *fileSystem) rootnode() inode {
 	return fs.root
 }
 
+func (fs *fileSystem) throttle() *throttle {
+	return fs.thr
+}
+
 func (fs *fileSystem) locker() sync.Locker {
 	return &fs.mutex
 }
@@ -449,7 +472,7 @@ func (fs *fileSystem) Rename(oldname, newname string) error {
 	// call nca.FS().Rename() instead of proceeding. Until then
 	// it's awkward for filesystems to implement their own Rename
 	// methods effectively: the only one that runs is the one on
-	// the root filesystem exposed to the caller (webdav, fuse,
+	// the root FileSystem exposed to the caller (webdav, fuse,
 	// etc).
 
 	// When acquiring locks on multiple inodes, avoid deadlock by
@@ -557,6 +580,11 @@ func (fs *fileSystem) Sync() error {
 	return ErrInvalidOperation
 }
 
+func (fs *fileSystem) Flush(string, bool) error {
+	log.Printf("TODO: flush fileSystem")
+	return ErrInvalidOperation
+}
+
 // rlookup (recursive lookup) returns the inode for the file/directory
 // with the given name (which may contain "/" separators). If no such
 // file/directory exists, the returned node is nil.
@@ -586,3 +614,7 @@ func rlookup(start inode, path string) (node inode, err error) {
 	}
 	return
 }
+
+func permittedName(name string) bool {
+	return name != "" && name != "." && name != ".." && !strings.Contains(name, "/")
+}