From: Nikolaus Rath <Nikolaus@rath.org>
Date: Mon, 17 Sep 2018 13:53:30 +0000 (+0100)
Subject: Don't enable adaptive readdirplus unless fs has readdir() handler.
X-Git-Tag: fuse-3.3.0~27
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7b0075c06f171cdac7a3d565463c0e5938dff04d;p=qemu-gpiodev%2Flibfuse.git

Don't enable adaptive readdirplus unless fs has readdir() handler.
---

diff --git a/ChangeLog.rst b/ChangeLog.rst
index af01d78..3d5c05b 100644
--- a/ChangeLog.rst
+++ b/ChangeLog.rst
@@ -1,3 +1,13 @@
+Unreleased Changes
+=================
+
+* The FUSE_CAP_READDIRPLUS_AUTO capability is no longer enabled by
+  default unless the file system defines both a readdir() and a
+  readdirplus() handler.
+
+* The description of the FUSE_CAP_READDIRPLUS_AUTO flag has been
+  improved.
+
 libfuse 3.2.6 (2018-08-31)
 ==========================
 
diff --git a/include/fuse_common.h b/include/fuse_common.h
index 29ad339..83c9dee 100644
--- a/include/fuse_common.h
+++ b/include/fuse_common.h
@@ -219,7 +219,7 @@ struct fuse_loop_config {
 #define FUSE_CAP_AUTO_INVAL_DATA	(1 << 12)
 
 /**
- * Indicates that the filesystem supports readdirplus
+ * Indicates that the filesystem supports readdirplus.
  *
  * This feature is enabled by default when supported by the kernel and if the
  * filesystem implements a readdirplus() handler.
@@ -227,10 +227,21 @@ struct fuse_loop_config {
 #define FUSE_CAP_READDIRPLUS		(1 << 13)
 
 /**
- * Indicates that the filesystem supports adaptive readdirplus
+ * Indicates that the filesystem supports adaptive readdirplus. 
  *
- * This feature is enabled by default when supported by the kernel and if the
- * filesystem implements a readdirplus() handler.
+ * If FUSE_CAP_READDIRPLUS is not set, this flag has no effect.
+ *
+ * If FUSE_CAP_READDIRPLUS is set and this flag is not set, the kernel
+ * will always issue readdirplus() requests to retrieve directory
+ * contents.
+ *
+ * If FUSE_CAP_READDIRPLUS is set and this flag is set, the kernel
+ * will issue both readdir() and readdirplus() requests, depending on
+ * how much information is expected to be required.
+ *
+ * This feature is enabled by default when supported by the kernel and
+ * if the filesystem implements both a readdirplus() and a readdir()
+ * handler.
  */
 #define FUSE_CAP_READDIRPLUS_AUTO	(1 << 14)
 
diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c
index c426b7c..e6e3d8d 100644
--- a/lib/fuse_lowlevel.c
+++ b/lib/fuse_lowlevel.c
@@ -1918,7 +1918,8 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
 		       FUSE_CAP_POSIX_LOCKS);
 	LL_SET_DEFAULT(se->op.flock, FUSE_CAP_FLOCK_LOCKS);
 	LL_SET_DEFAULT(se->op.readdirplus, FUSE_CAP_READDIRPLUS);
-	LL_SET_DEFAULT(se->op.readdirplus, FUSE_CAP_READDIRPLUS_AUTO);
+	LL_SET_DEFAULT(se->op.readdirplus && se->op.readdir,
+		       FUSE_CAP_READDIRPLUS_AUTO);
 	se->conn.time_gran = 1;
 	
 	if (bufsize < FUSE_MIN_READ_BUFFER) {