Support the lack of paths when cache is off

Before FUSE 2.9, FUSE had to emulate unlink() if a file was still open
via renaming to a hidden file.  This was due to the requirement that a
valid "path" argument must be submitted for many FUSE operations. FUSE
2.9 introduced the flag_nullpath_ok and flag_nopath flags that allow a
FUSE file system to signal to FUSE that the "path" argument may be NULL
in certain operations.

sshfs doesn't require paths if the cache isn't used so communicate
that information to the FUSE layer.

2 files changed, 12 insertions, 0 deletions

diff --git a/cache.c b/cache.c
index aeb14ec..34a87ca 100644
--- a/cache.c
+++ b/cache.c
@@ -523,6 +523,10 @@ static void cache_unity_fill(struct fuse_cache_operations *oper,
 	cache_oper->ftruncate   = oper->oper.ftruncate;
 	cache_oper->fgetattr    = oper->oper.fgetattr;
 #endif
+#if FUSE_VERSION >= 29
+	cache_oper->flag_nullpath_ok = oper->oper.flag_nullpath_ok;
+	cache_oper->flag_nopath  = oper->oper.flag_nopath;
+#endif
 }
 
 static void cache_fill(struct fuse_cache_operations *oper,
@@ -548,6 +552,10 @@ static void cache_fill(struct fuse_cache_operations *oper,
 	cache_oper->ftruncate = oper->oper.ftruncate ? cache_ftruncate : NULL;
 	cache_oper->fgetattr = oper->oper.fgetattr ? cache_fgetattr : NULL;
 #endif
+#if FUSE_VERSION >= 29
+	cache_oper->flag_nullpath_ok = 0;
+	cache_oper->flag_nopath = 0;
+#endif
 
 }
 
diff --git a/sshfs.c b/sshfs.c
index 9fb68af..f41d987 100644
--- a/sshfs.c
+++ b/sshfs.c
@@ -3373,6 +3373,10 @@ static struct fuse_cache_operations sshfs_oper = {
 		.ftruncate  = sshfs_ftruncate,
 		.fgetattr   = sshfs_fgetattr,
 #endif
+#if FUSE_VERSION >= 29
+		.flag_nullpath_ok = 1,
+		.flag_nopath = 1,
+#endif
 	},
 	.cache_getdir = sshfs_getdir,
 };