X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/8296c0784c70660e0a7247ba000741d37bda38fd..d8d6bca4b5db4851a29473f08dc600816c977a21:/sdk/go/arvados/fs_base.go

diff --git a/sdk/go/arvados/fs_base.go b/sdk/go/arvados/fs_base.go
index 369b4bb942..2478641df5 100644
--- a/sdk/go/arvados/fs_base.go
+++ b/sdk/go/arvados/fs_base.go
@@ -31,6 +31,10 @@ var (
 	ErrPermission        = os.ErrPermission
 )
 
+type syncer interface {
+	Sync() error
+}
+
 // A File is an *os.File-like interface for reading and writing files
 // in a FileSystem.
 type File interface {
@@ -58,6 +62,9 @@ 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 +93,22 @@ 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
+
+	// Estimate current memory usage.
+	MemorySize() int64
 }
 
 type inode interface {
@@ -103,6 +125,9 @@ 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
@@ -134,6 +159,7 @@ type inode interface {
 	sync.Locker
 	RLock()
 	RUnlock()
+	MemorySize() int64
 }
 
 type fileinfo struct {
@@ -207,6 +233,13 @@ func (*nullnode) Child(name string, replace func(inode) (inode, error)) (inode,
 	return nil, ErrNotADirectory
 }
 
+func (*nullnode) MemorySize() int64 {
+	// Types that embed nullnode should report their own size, but
+	// if they don't, we at least report a non-zero size to ensure
+	// a large tree doesn't get reported as 0 bytes.
+	return 64
+}
+
 type treenode struct {
 	fs       FileSystem
 	parent   inode
@@ -281,16 +314,46 @@ func (n *treenode) Readdir() (fi []os.FileInfo, err error) {
 	return
 }
 
+func (n *treenode) Sync() error {
+	n.RLock()
+	defer n.RUnlock()
+	for _, inode := range n.inodes {
+		syncer, ok := inode.(syncer)
+		if !ok {
+			return ErrInvalidOperation
+		}
+		err := syncer.Sync()
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (n *treenode) MemorySize() (size int64) {
+	n.RLock()
+	defer n.RUnlock()
+	for _, inode := range n.inodes {
+		size += inode.MemorySize()
+	}
+	return
+}
+
 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 +512,7 @@ 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
@@ -553,10 +616,21 @@ func (fs *fileSystem) remove(name string, recursive bool) error {
 }
 
 func (fs *fileSystem) Sync() error {
-	log.Printf("TODO: sync fileSystem")
+	if syncer, ok := fs.root.(syncer); ok {
+		return syncer.Sync()
+	}
+	return ErrInvalidOperation
+}
+
+func (fs *fileSystem) Flush(string, bool) error {
+	log.Printf("TODO: flush fileSystem")
 	return ErrInvalidOperation
 }
 
+func (fs *fileSystem) MemorySize() int64 {
+	return fs.root.MemorySize()
+}
+
 // 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 +660,7 @@ func rlookup(start inode, path string) (node inode, err error) {
 	}
 	return
 }
+
+func permittedName(name string) bool {
+	return name != "" && name != "." && name != ".." && !strings.Contains(name, "/")
+}